02_GERG2008.js

// Version 2.0 of routines for the calculation of thermodynamic
// properties from the AGA 8 Part 2 GERG-2008 equation of state.
// April, 2017
//Written by Eric W. Lemmon
//Applied Chemicals and Materials Division
//National Institute of Standards and Technology (NIST)
//Boulder, Colorado, USA
//Eric.Lemmon@nist.gov
//303-497-7939
function SetupFlowStreamSimulator(){
  //The following routine must be called once before any other routine.
    //Initialize all the constants and parameters in the GERG-2008 model.
    //Some values are modified for calculations that do not depend on T, D, and x in order to speed up the program.
    RGERG = 8.314472;
    let i;
    let j;
    let o13 = 1 / 3;
    let bijk=zeros2(MaxMdl + 1,MaxTrmM + 1);
    let Rs = 8.31451;
    let Rsr = Rs / RGERG;
    let n1;
    let n2;
    let T0;
    let d0;
    for (i = 1 ; i <= MaxFlds; i++){xold[i] = 0}
    Told = 0;
    //Molar masses (g/mol)
    MMiGERG[1] = 16.04246;    //Methane
    MMiGERG[2] = 28.0134;     //Nitrogen
    MMiGERG[3] = 44.0095;     //Carbon dioxide
    MMiGERG[4] = 30.06904;    //Ethane
    MMiGERG[5] = 44.09562;   //Propane
    MMiGERG[6] = 58.1222;     //Isobutane
    MMiGERG[7] = 58.1222;     //n-Butane
    MMiGERG[8] = 72.14878;    //Isopentane
    MMiGERG[9] = 72.14878;    //n-Pentane
    MMiGERG[10] = 86.17536;   //Hexane
    MMiGERG[11] = 100.20194;  //Heptane
    MMiGERG[12] = 114.22852;  //Octane
    MMiGERG[13] = 128.2551;   //Nonane
    MMiGERG[14] = 142.28168;  //Decane
    MMiGERG[15] = 2.01588;    //Hydrogen
    MMiGERG[16] = 31.9988;    //Oxygen
    MMiGERG[17] = 28.0101;    //Carbon monoxide
    MMiGERG[18] = 18.01528;   //Water
    MMiGERG[19] = 34.08088;   //Hydrogen sulfide
    MMiGERG[20] = 4.002602;   //Helium
    MMiGERG[21] = 39.948;     //Argon
    //Number of polynomial and exponential terms
    for (i = 1; i <= MaxFlds; i++){kpol[i] = 6;kexp[i] = 6}
    kexp[1] = 18;
    kexp[2] = 18;
    kexp[4] = 18;
    kpol[3] = 4;    kexp[3] = 18;
    kpol[15] = 5;   kexp[15] = 9;
    kpol[18] = 7;   kexp[18] = 9;
    kpol[20] = 4;   kexp[20] = 8;
    kpolij[1] = 2;  kexpij[1] = 10;
    kpolij[2] = 5;  kexpij[2] = 4;
    kpolij[3] = 2;  kexpij[3] = 7;
    kpolij[4] = 3;  kexpij[4] = 3;
    kpolij[5] = 2;  kexpij[5] = 4;
    kpolij[6] = 3;  kexpij[6] = 3;
    kpolij[7] = 4;  kexpij[7] = 0;
    kpolij[10] = 10; kexpij[10] = 0;
    //Critical densities [mol/l]
    Dc[1] = 10.139342719;
    Dc[2] = 11.1839;
    Dc[3] = 10.624978698;
    Dc[4] = 6.87085454;
    Dc[5] = 5.000043088;
    Dc[6] = 3.86014294;
    Dc[7] = 3.920016792;
    Dc[8] = 3.271;
    Dc[9] = 3.215577588;
    Dc[10] = 2.705877875;
    Dc[11] = 2.315324434;
    Dc[12] = 2.056404127;
    Dc[13] = 1.81;
    Dc[14] = 1.64;
    Dc[15] = 14.94;
    Dc[16] = 13.63;
    Dc[17] = 10.85;
    Dc[18] = 17.87371609;
    Dc[19] = 10.19;
    Dc[20] = 17.399;
    Dc[21] = 13.407429659;
    //Critical temperatures [K]
    Tc[1] = 190.564;
    Tc[2] = 126.192;
    Tc[3] = 304.1282;
    Tc[4] = 305.322;
    Tc[5] = 369.825;
    Tc[6] = 407.817;
    Tc[7] = 425.125;
    Tc[8] = 460.35;
    Tc[9] = 469.7;
    Tc[10] = 507.82;
    Tc[11] = 540.13;
    Tc[12] = 569.32;
    Tc[13] = 594.55;
    Tc[14] = 617.7;
    Tc[15] = 33.19;
    Tc[16] = 154.595;
    Tc[17] = 132.86;
    Tc[18] = 647.096;
    Tc[19] = 373.1;
    Tc[20] = 5.1953;
    Tc[21] = 150.687;
    //Exponents in pure fluid equations
    for (let i = 1 ; i <= MaxFlds; i++){
      Vc3[i] = 1 / Math.pow(Dc[i],o13) / 2;
      Tc2[i] = Math.sqrt(Tc[i]);
      coik[i][1] = 0;  doik[i][1] = 1;  toik[i][1] = 0.25;
      coik[i][2] = 0;  doik[i][2] = 1;  toik[i][2] = 1.125;
      coik[i][3] = 0;  doik[i][3] = 1;  toik[i][3] = 1.5;
      coik[i][4] = 0;  doik[i][4] = 2;  toik[i][4] = 1.375;
      coik[i][5] = 0;  doik[i][5] = 3;  toik[i][5] = 0.25;
      coik[i][6] = 0;  doik[i][6] = 7;  toik[i][6] = 0.875;
      coik[i][7] = 1;  doik[i][7] = 2;  toik[i][7] = 0.625;
      coik[i][8] = 1;  doik[i][8] = 5;  toik[i][8] = 1.75;
      coik[i][9] = 2;  doik[i][9] = 1;  toik[i][9] = 3.625;
      coik[i][10] = 2; doik[i][10] = 4; toik[i][10] = 3.625;
      coik[i][11] = 3; doik[i][11] = 3; toik[i][11] = 14.5;
      coik[i][12] = 3; doik[i][12] = 4; toik[i][12] = 12;
    }
    for (i = 1 ; i <= 4; i++){
      if (i != 3){
        coik[i][1] = 0;  doik[i][1] = 1;  toik[i][1] = 0.125;
        coik[i][2] = 0;  doik[i][2] = 1;  toik[i][2] = 1.125;
        coik[i][3] = 0;  doik[i][3] = 2;  toik[i][3] = 0.375;
        coik[i][4] = 0;  doik[i][4] = 2;  toik[i][4] = 1.125;
        coik[i][5] = 0;  doik[i][5] = 4;  toik[i][5] = 0.625;
        coik[i][6] = 0;  doik[i][6] = 4;  toik[i][6] = 1.5;
        coik[i][7] = 1;  doik[i][7] = 1;  toik[i][7] = 0.625;
        coik[i][8] = 1;  doik[i][8] = 1;  toik[i][8] = 2.625;
        coik[i][9] = 1;  doik[i][9] = 1;  toik[i][9] = 2.75;
        coik[i][10] = 1; doik[i][10] = 2; toik[i][10] = 2.125;
        coik[i][11] = 1; doik[i][11] = 3; toik[i][11] = 2;
        coik[i][12] = 1; doik[i][12] = 6; toik[i][12] = 1.75;
        coik[i][13] = 2; doik[i][13] = 2; toik[i][13] = 4.5;
        coik[i][14] = 2; doik[i][14] = 3; toik[i][14] = 4.75;
        coik[i][15] = 2; doik[i][15] = 3; toik[i][15] = 5;
        coik[i][16] = 2; doik[i][16] = 4; toik[i][16] = 4;
        coik[i][17] = 2; doik[i][17] = 4; toik[i][17] = 4.5;
        coik[i][18] = 3; doik[i][18] = 2; toik[i][18] = 7.5;
        coik[i][19] = 3; doik[i][19] = 3; toik[i][19] = 14;
        coik[i][20] = 3; doik[i][20] = 4; toik[i][20] = 11.5;
        coik[i][21] = 6; doik[i][21] = 5; toik[i][21] = 26;
        coik[i][22] = 6; doik[i][22] = 6; toik[i][22] = 28;
        coik[i][23] = 6; doik[i][23] = 6; toik[i][23] = 30;
        coik[i][24] = 6; doik[i][24] = 7; toik[i][24] = 16;
      }
    }
    //Coefficients of pure fluid equations
    //Methane
    noik[1][1] = 0.57335704239162;
    noik[1][2] = -1.676068752373;
    noik[1][3] = 0.23405291834916;
    noik[1][4] = -0.21947376343441;
    noik[1][5] = 0.016369201404128;
    noik[1][6] = 0.01500440638928;
    noik[1][7] = 0.098990489492918;
    noik[1][8] = 0.58382770929055;
    noik[1][9] = -0.7478686756039;
    noik[1][10] = 0.30033302857974;
    noik[1][11] = 0.20985543806568;
    noik[1][12] = -0.018590151133061;
    noik[1][13] = -0.15782558339049;
    noik[1][14] = 0.12716735220791;
    noik[1][15] = -0.032019743894346;
    noik[1][16] = -0.068049729364536;
    noik[1][17] = 0.024291412853736;
    noik[1][18] = 5.1440451639444E-03;
    noik[1][19] = -0.019084949733532;
    noik[1][20] = 5.5229677241291E-03;
    noik[1][21] = -4.4197392976085E-03;
    noik[1][22] = 0.040061416708429;
    noik[1][23] = -0.033752085907575;
    noik[1][24] = -2.5127658213357E-03;
    //Nitrogen
    noik[2][1] = 0.59889711801201;
    noik[2][2] = -1.6941557480731;
    noik[2][3] = 0.24579736191718;
    noik[2][4] = -0.23722456755175;
    noik[2][5] = 0.017954918715141;
    noik[2][6] = 0.014592875720215;
    noik[2][7] = 0.10008065936206;
    noik[2][8] = 0.73157115385532;
    noik[2][9] = -0.88372272336366;
    noik[2][10] = 0.31887660246708;
    noik[2][11] = 0.20766491728799;
    noik[2][12] = -0.019379315454158;
    noik[2][13] = -0.16936641554983;
    noik[2][14] = 0.13546846041701;
    noik[2][15] = -0.033066712095307;
    noik[2][16] = -0.060690817018557;
    noik[2][17] = 0.012797548292871;
    noik[2][18] = 5.8743664107299E-03;
    noik[2][19] = -0.018451951971969;
    noik[2][20] = 4.7226622042472E-03;
    noik[2][21] = -5.2024079680599E-03;
    noik[2][22] = 0.043563505956635;
    noik[2][23] = -0.036251690750939;
    noik[2][24] = -2.8974026866543E-03;
    //Ethane
    noik[4][1] = 0.63596780450714;
    noik[4][2] = -1.7377981785459;
    noik[4][3] = 0.28914060926272;
    noik[4][4] = -0.33714276845694;
    noik[4][5] = 0.022405964699561;
    noik[4][6] = 0.015715424886913;
    noik[4][7] = 0.11450634253745;
    noik[4][8] = 1.0612049379745;
    noik[4][9] = -1.2855224439423;
    noik[4][10] = 0.39414630777652;
    noik[4][11] = 0.31390924682041;
    noik[4][12] = -0.021592277117247;
    noik[4][13] = -0.21723666564905;
    noik[4][14] = -0.28999574439489;
    noik[4][15] = 0.42321173025732;
    noik[4][16] = 0.04643410025926;
    noik[4][17] = -0.13138398329741;
    noik[4][18] = 0.011492850364368;
    noik[4][19] = -0.033387688429909;
    noik[4][20] = 0.015183171583644;
    noik[4][21] = -4.7610805647657E-03;
    noik[4][22] = 0.046917166277885;
    noik[4][23] = -0.039401755804649;
    noik[4][24] = -3.2569956247611E-03;
    //Propane
    noik[5][1] = 1.0403973107358;
    noik[5][2] = -2.8318404081403;
    noik[5][3] = 0.84393809606294;
    noik[5][4] = -0.076559591850023;
    noik[5][5] = 0.09469737305728;
    noik[5][6] = 2.4796475497006E-04;
    noik[5][7] = 0.2774376042287;
    noik[5][8] = -0.043846000648377;
    noik[5][9] = -0.2699106478435;
    noik[5][10] = -0.06931341308986;
    noik[5][11] = -0.029632145981653;
    noik[5][12] = 0.01404012675138;
    //Isobutane
    noik[6][1] = 1.04293315891;
    noik[6][2] = -2.8184272548892;
    noik[6][3] = 0.8617623239785;
    noik[6][4] = -0.10613619452487;
    noik[6][5] = 0.098615749302134;
    noik[6][6] = 2.3948208682322E-04;
    noik[6][7] = 0.3033000485695;
    noik[6][8] = -0.041598156135099;
    noik[6][9] = -0.29991937470058;
    noik[6][10] = -0.080369342764109;
    noik[6][11] = -0.029761373251151;
    noik[6][12] = 0.01305963030314;
    //n-Butane
    noik[7][1] = 1.0626277411455;
    noik[7][2] = -2.862095182835;
    noik[7][3] = 0.88738233403777;
    noik[7][4] = -0.12570581155345;
    noik[7][5] = 0.10286308708106;
    noik[7][6] = 2.5358040602654E-04;
    noik[7][7] = 0.32325200233982;
    noik[7][8] = -0.037950761057432;
    noik[7][9] = -0.32534802014452;
    noik[7][10] = -0.079050969051011;
    noik[7][11] = -0.020636720547775;
    noik[7][12] = 0.005705380933475;
    //Isopentane
    noik[8][1] = 1.0963;
    noik[8][2] = -3.0402;
    noik[8][3] = 1.0317;
    noik[8][4] = -0.1541;
    noik[8][5] = 0.11535;
    noik[8][6] = 0.00029809;
    noik[8][7] = 0.39571;
    noik[8][8] = -0.045881;
    noik[8][9] = -0.35804;
    noik[8][10] = -0.10107;
    noik[8][11] = -0.035484;
    noik[8][12] = 0.018156;
    //n-Pentane
    noik[9][1] = 1.0968643098001;
    noik[9][2] = -2.9988888298061;
    noik[9][3] = 0.99516886799212;
    noik[9][4] = -0.16170708558539;
    noik[9][5] = 0.11334460072775;
    noik[9][6] = 2.6760595150748E-04;
    noik[9][7] = 0.40979881986931;
    noik[9][8] = -0.040876423083075;
    noik[9][9] = -0.38169482469447;
    noik[9][10] = -0.10931956843993;
    noik[9][11] = -0.03207322332799;
    noik[9][12] = 0.016877016216975;
    //Hexane
    noik[10][1] = 1.0553238013661;
    noik[10][2] = -2.6120615890629;
    noik[10][3] = 0.7661388296726;
    noik[10][4] = -0.29770320622459;
    noik[10][5] = 0.11879907733358;
    noik[10][6] = 2.7922861062617E-04;
    noik[10][7] = 0.46347589844105;
    noik[10][8] = 0.011433196980297;
    noik[10][9] = -0.48256968738131;
    noik[10][10] = -0.093750558924659;
    noik[10][11] = -6.7273247155994E-03;
    noik[10][12] = -5.1141583585428E-03;
    //Heptane
    noik[11][1] = 1.0543747645262;
    noik[11][2] = -2.6500681506144;
    noik[11][3] = 0.81730047827543;
    noik[11][4] = -0.30451391253428;
    noik[11][5] = 0.122538687108;
    noik[11][6] = 2.7266472743928E-04;
    noik[11][7] = 0.4986582568167;
    noik[11][8] = -7.1432815084176E-04;
    noik[11][9] = -0.5423689552545;
    noik[11][10] = -0.13801821610756;
    noik[11][11] = -6.1595287380011E-03;
    noik[11][12] = 4.8602510393022E-04;
    //Octane
    noik[12][1] = 1.0722544875633;
    noik[12][2] = -2.4632951172003;
    noik[12][3] = 0.65386674054928;
    noik[12][4] = -0.36324974085628;
    noik[12][5] = 0.12713269626764;
    noik[12][6] = 3.071357277793E-04;
    noik[12][7] = 0.5265685698754;
    noik[12][8] = 0.019362862857653;
    noik[12][9] = -0.58939426849155;
    noik[12][10] = -0.14069963991934;
    noik[12][11] = -7.8966330500036E-03;
    noik[12][12] = 3.3036597968109E-03;
    //Nonane
    noik[13][1] = 1.1151;
    noik[13][2] = -2.702;
    noik[13][3] = 0.83416;
    noik[13][4] = -0.38828;
    noik[13][5] = 0.1376;
    noik[13][6] = 0.00028185;
    noik[13][7] = 0.62037;
    noik[13][8] = 0.015847;
    noik[13][9] = -0.61726;
    noik[13][10] = -0.15043;
    noik[13][11] = -0.012982;
    noik[13][12] = 0.0044325;
    //Decane
    noik[14][1] = 1.0461;
    noik[14][2] = -2.4807;
    noik[14][3] = 0.74372;
    noik[14][4] = -0.52579;
    noik[14][5] = 0.15315;
    noik[14][6] = 0.00032865;
    noik[14][7] = 0.84178;
    noik[14][8] = 0.055424;
    noik[14][9] = -0.73555;
    noik[14][10] = -0.18507;
    noik[14][11] = -0.020775;
    noik[14][12] = 0.012335;
    //Oxygen
    noik[16][1] = 0.88878286369701;
    noik[16][2] = -2.4879433312148;
    noik[16][3] = 0.59750190775886;
    noik[16][4] = 9.6501817061881E-03;
    noik[16][5] = 0.07197042871277;
    noik[16][6] = 2.2337443000195E-04;
    noik[16][7] = 0.18558686391474;
    noik[16][8] = -0.03812936803576;
    noik[16][9] = -0.15352245383006;
    noik[16][10] = -0.026726814910919;
    noik[16][11] = -0.025675298677127;
    noik[16][12] = 9.5714302123668E-03;
    //Carbon monoxide
    noik[17][1] = 0.90554;
    noik[17][2] = -2.4515;
    noik[17][3] = 0.53149;
    noik[17][4] = 0.024173;
    noik[17][5] = 0.072156;
    noik[17][6] = 0.00018818;
    noik[17][7] = 0.19405;
    noik[17][8] = -0.043268;
    noik[17][9] = -0.12778;
    noik[17][10] = -0.027896;
    noik[17][11] = -0.034154;
    noik[17][12] = 0.016329;
    //Hydrogen sulfide
    noik[19][1] = 0.87641;
    noik[19][2] = -2.0367;
    noik[19][3] = 0.21634;
    noik[19][4] = -0.050199;
    noik[19][5] = 0.066994;
    noik[19][6] = 0.00019076;
    noik[19][7] = 0.20227;
    noik[19][8] = -0.0045348;
    noik[19][9] = -0.2223;
    noik[19][10] = -0.034714;
    noik[19][11] = -0.014885;
    noik[19][12] = 0.0074154;
    //Argon
    noik[21][1] = 0.85095714803969;
    noik[21][2] = -2.400322294348;
    noik[21][3] = 0.54127841476466;
    noik[21][4] = 0.016919770692538;
    noik[21][5] = 0.068825965019035;
    noik[21][6] = 2.1428032815338E-04;
    noik[21][7] = 0.17429895321992;
    noik[21][8] = -0.033654495604194;
    noik[21][9] = -0.13526799857691;
    noik[21][10] = -0.016387350791552;
    noik[21][11] = -0.024987666851475;
    noik[21][12] = 8.8769204815709E-03;
    //Carbon dioxide
    coik[3][1] = 0;   doik[3][1] = 1;   toik[3][1] = 0;          noik[3][1] = 0.52646564804653;
    coik[3][2] = 0;   doik[3][2] = 1;   toik[3][2] = 1.25;       noik[3][2] = -1.4995725042592;
    coik[3][3] = 0;   doik[3][3] = 2;   toik[3][3] = 1.625;      noik[3][3] = 0.27329786733782;
    coik[3][4] = 0;   doik[3][4] = 3;   toik[3][4] = 0.375;      noik[3][4] = 0.12949500022786;
    coik[3][5] = 1;   doik[3][5] = 3;   toik[3][5] = 0.375;      noik[3][5] = 0.15404088341841;
    coik[3][6] = 1;   doik[3][6] = 3;   toik[3][6] = 1.375;      noik[3][6] = -0.58186950946814;
    coik[3][7] = 1;   doik[3][7] = 4;   toik[3][7] = 1.125;      noik[3][7] = -0.18022494838296;
    coik[3][8] = 1;   doik[3][8] = 5;   toik[3][8] = 1.375;      noik[3][8] = -0.095389904072812;
    coik[3][9] = 1;   doik[3][9] = 6;   toik[3][9] = 0.125;      noik[3][9] = -8.0486819317679E-03;
    coik[3][10] = 1;  doik[3][10] = 6;  toik[3][10] = 1.625;     noik[3][10] = -0.03554775127309;
    coik[3][11] = 2;  doik[3][11] = 1;  toik[3][11] = 3.75;      noik[3][11] = -0.28079014882405;
    coik[3][12] = 2;  doik[3][12] = 4;  toik[3][12] = 3.5;       noik[3][12] = -0.082435890081677;
    coik[3][13] = 3;  doik[3][13] = 1;  toik[3][13] = 7.5;       noik[3][13] = 0.010832427979006;
    coik[3][14] = 3;  doik[3][14] = 1;  toik[3][14] = 8;         noik[3][14] = -6.7073993161097E-03;
    coik[3][15] = 3;  doik[3][15] = 3;  toik[3][15] = 6;         noik[3][15] = -4.6827907600524E-03;
    coik[3][16] = 3;  doik[3][16] = 3;  toik[3][16] = 16;        noik[3][16] = -0.028359911832177;
    coik[3][17] = 3;  doik[3][17] = 4;  toik[3][17] = 11;        noik[3][17] = 0.019500174744098;
    coik[3][18] = 5;  doik[3][18] = 5;  toik[3][18] = 24;        noik[3][18] = -0.21609137507166;
    coik[3][19] = 5;  doik[3][19] = 5;  toik[3][19] = 26;        noik[3][19] = 0.43772794926972;
    coik[3][20] = 5;  doik[3][20] = 5;  toik[3][20] = 28;        noik[3][20] = -0.22130790113593;
    coik[3][21] = 6;  doik[3][21] = 5;  toik[3][21] = 24;        noik[3][21] = 0.015190189957331;
    coik[3][22] = 6;  doik[3][22] = 5;  toik[3][22] = 26;        noik[3][22] = -0.0153809489533;
    //Hydrogen
    coik[15][1] = 0;  doik[15][1] = 1;  toik[15][1] = 0.5;       noik[15][1] = 5.3579928451252;
    coik[15][2] = 0;  doik[15][2] = 1;  toik[15][2] = 0.625;     noik[15][2] = -6.2050252530595;
    coik[15][3] = 0;  doik[15][3] = 2;  toik[15][3] = 0.375;     noik[15][3] = 0.13830241327086;
    coik[15][4] = 0;  doik[15][4] = 2;  toik[15][4] = 0.625;     noik[15][4] = -0.071397954896129;
    coik[15][5] = 0;  doik[15][5] = 4;  toik[15][5] = 1.125;     noik[15][5] = 0.015474053959733;
    coik[15][6] = 1;  doik[15][6] = 1;  toik[15][6] = 2.625;     noik[15][6] = -0.14976806405771;
    coik[15][7] = 1;  doik[15][7] = 5;  toik[15][7] = 0;         noik[15][7] = -0.026368723988451;
    coik[15][8] = 1;  doik[15][8] = 5;  toik[15][8] = 0.25;      noik[15][8] = 0.056681303156066;
    coik[15][9] = 1;  doik[15][9] = 5;  toik[15][9] = 1.375;     noik[15][9] = -0.060063958030436;
    coik[15][10] = 2; doik[15][10] = 1; toik[15][10] = 4;        noik[15][10] = -0.45043942027132;
    coik[15][11] = 2; doik[15][11] = 1; toik[15][11] = 4.25;     noik[15][11] = 0.424788402445;
    coik[15][12] = 3; doik[15][12] = 2; toik[15][12] = 5;        noik[15][12] = -0.021997640827139;
    coik[15][13] = 3; doik[15][13] = 5; toik[15][13] = 8;        noik[15][13] = -0.01049952137453;
    coik[15][14] = 5; doik[15][14] = 1; toik[15][14] = 8;        noik[15][14] = -2.8955902866816E-03;
    //Water
    coik[18][1] = 0;  doik[18][1] = 1;  toik[18][1] = 0.5;       noik[18][1] = 0.82728408749586;
    coik[18][2] = 0;  doik[18][2] = 1;  toik[18][2] = 1.25;      noik[18][2] = -1.8602220416584;
    coik[18][3] = 0;  doik[18][3] = 1;  toik[18][3] = 1.875;     noik[18][3] = -1.1199009613744;
    coik[18][4] = 0;  doik[18][4] = 2;  toik[18][4] = 0.125;     noik[18][4] = 0.15635753976056;
    coik[18][5] = 0;  doik[18][5] = 2;  toik[18][5] = 1.5;       noik[18][5] = 0.87375844859025;
    coik[18][6] = 0;  doik[18][6] = 3;  toik[18][6] = 1;         noik[18][6] = -0.36674403715731;
    coik[18][7] = 0;  doik[18][7] = 4;  toik[18][7] = 0.75;      noik[18][7] = 0.053987893432436;
    coik[18][8] = 1;  doik[18][8] = 1;  toik[18][8] = 1.5;       noik[18][8] = 1.0957690214499;
    coik[18][9] = 1;  doik[18][9] = 5;  toik[18][9] = 0.625;     noik[18][9] = 0.053213037828563;
    coik[18][10] = 1; doik[18][10] = 5; toik[18][10] = 2.625;    noik[18][10] = 0.013050533930825;
    coik[18][11] = 2; doik[18][11] = 1; toik[18][11] = 5;        noik[18][11] = -0.41079520434476;
    coik[18][12] = 2; doik[18][12] = 2; toik[18][12] = 4;        noik[18][12] = 0.1463744334412;
    coik[18][13] = 2; doik[18][13] = 4; toik[18][13] = 4.5;      noik[18][13] = -0.055726838623719;
    coik[18][14] = 3; doik[18][14] = 4; toik[18][14] = 3;        noik[18][14] = -0.0112017741438;
    coik[18][15] = 5; doik[18][15] = 1; toik[18][15] = 4;        noik[18][15] = -6.6062758068099E-03;
    coik[18][16] = 5; doik[18][16] = 1; toik[18][16] = 6;        noik[18][16] = 4.6918522004538E-03;
    //Helium
    coik[20][1] = 0;  doik[20][1] = 1;  toik[20][1] = 0;         noik[20][1] = -0.45579024006737;
    coik[20][2] = 0;  doik[20][2] = 1;  toik[20][2] = 0.125;     noik[20][2] = 1.2516390754925;
    coik[20][3] = 0;  doik[20][3] = 1;  toik[20][3] = 0.75;      noik[20][3] = -1.5438231650621;
    coik[20][4] = 0;  doik[20][4] = 4;  toik[20][4] = 1;         noik[20][4] = 0.020467489707221;
    coik[20][5] = 1;  doik[20][5] = 1;  toik[20][5] = 0.75;      noik[20][5] = -0.34476212380781;
    coik[20][6] = 1;  doik[20][6] = 3;  toik[20][6] = 2.625;     noik[20][6] = -0.020858459512787;
    coik[20][7] = 1;  doik[20][7] = 5;  toik[20][7] = 0.125;     noik[20][7] = 0.016227414711778;
    coik[20][8] = 1;  doik[20][8] = 5;  toik[20][8] = 1.25;      noik[20][8] = -0.057471818200892;
    coik[20][9] = 1;  doik[20][9] = 5;  toik[20][9] = 2;         noik[20][9] = 0.019462416430715;
    coik[20][10] = 2; doik[20][10] = 2; toik[20][10] = 1;        noik[20][10] = -0.03329568012302;
    coik[20][11] = 3; doik[20][11] = 1; toik[20][11] = 4.5;      noik[20][11] = -0.010863577372367;
    coik[20][12] = 3; doik[20][12] = 2; toik[20][12] = 5;        noik[20][12] = -0.022173365245954;
    //Exponents in mixture equations
    //Methane-Nitrogen
    dijk[3][1] = 1;  tijk[3][1] = 0;     cijk[3][1] = 0;     eijk[3][1] = 0;    bijk[3][1] = 0;    gijk[3][1] = 0;    nijk[3][1] = -9.8038985517335E-03;
    dijk[3][2] = 4;  tijk[3][2] = 1.85;  cijk[3][2] = 0;     eijk[3][2] = 0;    bijk[3][2] = 0;    gijk[3][2] = 0;    nijk[3][2] = 4.2487270143005E-04;
    dijk[3][3] = 1;  tijk[3][3] = 7.85;  cijk[3][3] = 1;     eijk[3][3] = 0.5;  bijk[3][3] = 1;    gijk[3][3] = 0.5;  nijk[3][3] = -0.034800214576142;
    dijk[3][4] = 2;  tijk[3][4] = 5.4;   cijk[3][4] = 1;     eijk[3][4] = 0.5;  bijk[3][4] = 1;    gijk[3][4] = 0.5;  nijk[3][4] = -0.13333813013896;
    dijk[3][5] = 2;  tijk[3][5] = 0;     cijk[3][5] = 0.25;  eijk[3][5] = 0.5;  bijk[3][5] = 2.5;  gijk[3][5] = 0.5;  nijk[3][5] = -0.011993694974627;
    dijk[3][6] = 2;  tijk[3][6] = 0.75;  cijk[3][6] = 0;     eijk[3][6] = 0.5;  bijk[3][6] = 3;    gijk[3][6] = 0.5;  nijk[3][6] = 0.069243379775168;
    dijk[3][7] = 2;  tijk[3][7] = 2.8;   cijk[3][7] = 0;     eijk[3][7] = 0.5;  bijk[3][7] = 3;    gijk[3][7] = 0.5;  nijk[3][7] = -0.31022508148249;
    dijk[3][8] = 2;  tijk[3][8] = 4.45;  cijk[3][8] = 0;     eijk[3][8] = 0.5;  bijk[3][8] = 3;    gijk[3][8] = 0.5;  nijk[3][8] = 0.24495491753226;
    dijk[3][9] = 3;  tijk[3][9] = 4.25;  cijk[3][9] = 0;     eijk[3][9] = 0.5;  bijk[3][9] = 3;    gijk[3][9] = 0.5;  nijk[3][9] = 0.22369816716981;
    //Methane-Carbon dioxide
    dijk[4][1] = 1;  tijk[4][1] = 2.6;   cijk[4][1] = 0;     eijk[4][1] = 0;    bijk[4][1] = 0;    gijk[4][1] = 0;    nijk[4][1] = -0.10859387354942;
    dijk[4][2] = 2;  tijk[4][2] = 1.95;  cijk[4][2] = 0;     eijk[4][2] = 0;    bijk[4][2] = 0;    gijk[4][2] = 0;    nijk[4][2] = 0.080228576727389;
    dijk[4][3] = 3;  tijk[4][3] = 0;     cijk[4][3] = 0;     eijk[4][3] = 0;    bijk[4][3] = 0;    gijk[4][3] = 0;    nijk[4][3] = -9.3303985115717E-03;
    dijk[4][4] = 1;  tijk[4][4] = 3.95;  cijk[4][4] = 1;     eijk[4][4] = 0.5;  bijk[4][4] = 1;    gijk[4][4] = 0.5;  nijk[4][4] = 0.040989274005848;
    dijk[4][5] = 2;  tijk[4][5] = 7.95;  cijk[4][5] = 0.5;   eijk[4][5] = 0.5;  bijk[4][5] = 2;    gijk[4][5] = 0.5;  nijk[4][5] = -0.24338019772494;
    dijk[4][6] = 3;  tijk[4][6] = 8;     cijk[4][6] = 0;     eijk[4][6] = 0.5;  bijk[4][6] = 3;    gijk[4][6] = 0.5;  nijk[4][6] = 0.23855347281124;
    //Methane-Ethane
    dijk[1][1] = 3;  tijk[1][1] = 0.65;  cijk[1][1] = 0;     eijk[1][1] = 0;    bijk[1][1] = 0;    gijk[1][1] = 0;    nijk[1][1] = -8.0926050298746E-04;
    dijk[1][2] = 4;  tijk[1][2] = 1.55;  cijk[1][2] = 0;     eijk[1][2] = 0;    bijk[1][2] = 0;    gijk[1][2] = 0;    nijk[1][2] = -7.5381925080059E-04;
    dijk[1][3] = 1;  tijk[1][3] = 3.1;   cijk[1][3] = 1;     eijk[1][3] = 0.5;  bijk[1][3] = 1;    gijk[1][3] = 0.5;  nijk[1][3] = -0.041618768891219;
    dijk[1][4] = 2;  tijk[1][4] = 5.9;   cijk[1][4] = 1;     eijk[1][4] = 0.5;  bijk[1][4] = 1;    gijk[1][4] = 0.5;  nijk[1][4] = -0.23452173681569;
    dijk[1][5] = 2;  tijk[1][5] = 7.05;  cijk[1][5] = 1;     eijk[1][5] = 0.5;  bijk[1][5] = 1;    gijk[1][5] = 0.5;  nijk[1][5] = 0.14003840584586;
    dijk[1][6] = 2;  tijk[1][6] = 3.35;  cijk[1][6] = 0.875; eijk[1][6] = 0.5;  bijk[1][6] = 1.25; gijk[1][6] = 0.5;  nijk[1][6] = 0.063281744807738;
    dijk[1][7] = 2;  tijk[1][7] = 1.2;   cijk[1][7] = 0.75;  eijk[1][7] = 0.5;  bijk[1][7] = 1.5;  gijk[1][7] = 0.5;  nijk[1][7] = -0.034660425848809;
    dijk[1][8] = 2;  tijk[1][8] = 5.8;   cijk[1][8] = 0.5;   eijk[1][8] = 0.5;  bijk[1][8] = 2;    gijk[1][8] = 0.5;  nijk[1][8] = -0.23918747334251;
    dijk[1][9] = 2;  tijk[1][9] = 2.7;   cijk[1][9] = 0;     eijk[1][9] = 0.5;  bijk[1][9] = 3;    gijk[1][9] = 0.5;  nijk[1][9] = 1.9855255066891E-03;
    dijk[1][10] = 3; tijk[1][10] = 0.45; cijk[1][10] = 0;    eijk[1][10] = 0.5; bijk[1][10] = 3;   gijk[1][10] = 0.5; nijk[1][10] = 6.1777746171555;
    dijk[1][11] = 3; tijk[1][11] = 0.55; cijk[1][11] = 0;    eijk[1][11] = 0.5; bijk[1][11] = 3;   gijk[1][11] = 0.5; nijk[1][11] = -6.9575358271105;
    dijk[1][12] = 3; tijk[1][12] = 1.95; cijk[1][12] = 0;    eijk[1][12] = 0.5; bijk[1][12] = 3;   gijk[1][12] = 0.5; nijk[1][12] = 1.0630185306388;
    //Methane-Propane
    dijk[2][1] = 3;  tijk[2][1] = 1.85;  cijk[2][1] = 0;     eijk[2][1] = 0;    bijk[2][1] = 0;    gijk[2][1] = 0;    nijk[2][1] = 0.013746429958576;
    dijk[2][2] = 3;  tijk[2][2] = 3.95;  cijk[2][2] = 0;     eijk[2][2] = 0;    bijk[2][2] = 0;    gijk[2][2] = 0;    nijk[2][2] = -7.4425012129552E-03;
    dijk[2][3] = 4;  tijk[2][3] = 0;     cijk[2][3] = 0;     eijk[2][3] = 0;    bijk[2][3] = 0;    gijk[2][3] = 0;    nijk[2][3] = -4.5516600213685E-03;
    dijk[2][4] = 4;  tijk[2][4] = 1.85;  cijk[2][4] = 0;     eijk[2][4] = 0;    bijk[2][4] = 0;    gijk[2][4] = 0;    nijk[2][4] = -5.4546603350237E-03;
    dijk[2][5] = 4;  tijk[2][5] = 3.85;  cijk[2][5] = 0;     eijk[2][5] = 0;    bijk[2][5] = 0;    gijk[2][5] = 0;    nijk[2][5] = 2.3682016824471E-03;
    dijk[2][6] = 1;  tijk[2][6] = 5.25;  cijk[2][6] = 0.25;  eijk[2][6] = 0.5;  bijk[2][6] = 0.75; gijk[2][6] = 0.5;  nijk[2][6] = 0.18007763721438;
    dijk[2][7] = 1;  tijk[2][7] = 3.85;  cijk[2][7] = 0.25;  eijk[2][7] = 0.5;  bijk[2][7] = 1;    gijk[2][7] = 0.5;  nijk[2][7] = -0.44773942932486;
    dijk[2][8] = 1;  tijk[2][8] = 0.2;   cijk[2][8] = 0;     eijk[2][8] = 0.5;  bijk[2][8] = 2;    gijk[2][8] = 0.5;  nijk[2][8] = 0.0193273748882;
    dijk[2][9] = 2;  tijk[2][9] = 6.5;   cijk[2][9] = 0;     eijk[2][9] = 0.5;  bijk[2][9] = 3;    gijk[2][9] = 0.5;  nijk[2][9] = -0.30632197804624;
    //Nitrogen-Carbon dioxide
    dijk[5][1] = 2;  tijk[5][1] = 1.85;  cijk[5][1] = 0;     eijk[5][1] = 0;    bijk[5][1] = 0;    gijk[5][1] = 0;    nijk[5][1] = 0.28661625028399;
    dijk[5][2] = 3;  tijk[5][2] = 1.4;   cijk[5][2] = 0;     eijk[5][2] = 0;    bijk[5][2] = 0;    gijk[5][2] = 0;    nijk[5][2] = -0.10919833861247;
    dijk[5][3] = 1;  tijk[5][3] = 3.2;   cijk[5][3] = 0.25;  eijk[5][3] = 0.5;  bijk[5][3] = 0.75; gijk[5][3] = 0.5;  nijk[5][3] = -1.137403208227;
    dijk[5][4] = 1;  tijk[5][4] = 2.5;   cijk[5][4] = 0.25;  eijk[5][4] = 0.5;  bijk[5][4] = 1;    gijk[5][4] = 0.5;  nijk[5][4] = 0.76580544237358;
    dijk[5][5] = 1;  tijk[5][5] = 8;     cijk[5][5] = 0;     eijk[5][5] = 0.5;  bijk[5][5] = 2;    gijk[5][5] = 0.5;  nijk[5][5] = 4.2638000926819E-03;
    dijk[5][6] = 2;  tijk[5][6] = 3.75;  cijk[5][6] = 0;     eijk[5][6] = 0.5;  bijk[5][6] = 3;    gijk[5][6] = 0.5;  nijk[5][6] = 0.17673538204534;
    //Nitrogen-Ethane
    dijk[6][1] = 2;  tijk[6][1] = 0;     cijk[6][1] = 0;     eijk[6][1] = 0;    bijk[6][1] = 0;    gijk[6][1] = 0;    nijk[6][1] = -0.47376518126608;
    dijk[6][2] = 2;  tijk[6][2] = 0.05;  cijk[6][2] = 0;     eijk[6][2] = 0;    bijk[6][2] = 0;    gijk[6][2] = 0;    nijk[6][2] = 0.48961193461001;
    dijk[6][3] = 3;  tijk[6][3] = 0;     cijk[6][3] = 0;     eijk[6][3] = 0;    bijk[6][3] = 0;    gijk[6][3] = 0;    nijk[6][3] = -5.7011062090535E-03;
    dijk[6][4] = 1;  tijk[6][4] = 3.65;  cijk[6][4] = 1;     eijk[6][4] = 0.5;  bijk[6][4] = 1;    gijk[6][4] = 0.5;  nijk[6][4] = -0.1996682004132;
    dijk[6][5] = 2;  tijk[6][5] = 4.9;   cijk[6][5] = 1;     eijk[6][5] = 0.5;  bijk[6][5] = 1;    gijk[6][5] = 0.5;  nijk[6][5] = -0.69411103101723;
    dijk[6][6] = 2;  tijk[6][6] = 4.45;  cijk[6][6] = 0.875; eijk[6][6] = 0.5;  bijk[6][6] = 1.25; gijk[6][6] = 0.5;  nijk[6][6] = 0.69226192739021;
    //Methane-Hydrogen
    dijk[7][1] = 1;  tijk[7][1] = 2;     cijk[7][1] = 0;     eijk[7][1] = 0;    bijk[7][1] = 0;    gijk[7][1] = 0;    nijk[7][1] = -0.25157134971934;
    dijk[7][2] = 3;  tijk[7][2] = -1;    cijk[7][2] = 0;     eijk[7][2] = 0;    bijk[7][2] = 0;    gijk[7][2] = 0;    nijk[7][2] = -6.2203841111983E-03;
    dijk[7][3] = 3;  tijk[7][3] = 1.75;  cijk[7][3] = 0;     eijk[7][3] = 0;    bijk[7][3] = 0;    gijk[7][3] = 0;    nijk[7][3] = 0.088850315184396;
    dijk[7][4] = 4;  tijk[7][4] = 1.4;   cijk[7][4] = 0;     eijk[7][4] = 0;    bijk[7][4] = 0;    gijk[7][4] = 0;    nijk[7][4] = -0.035592212573239;
    //Methane-n-Butane][Methane-Isobutane][Ethane-Propane][Ethane-n-Butane,
    //Ethane-Isobutane][Propane-n-Butane][Propane-Isobutane][and n-Butane-Isobutane
    dijk[10][1] = 1;  tijk[10][1] = 1;     cijk[10][1] = 0;  eijk[10][1] = 0;   bijk[10][1] = 0;   gijk[10][1] = 0;   nijk[10][1] = 2.5574776844118;
    dijk[10][2] = 1;  tijk[10][2] = 1.55;  cijk[10][2] = 0;  eijk[10][2] = 0;   bijk[10][2] = 0;   gijk[10][2] = 0;   nijk[10][2] = -7.9846357136353;
    dijk[10][3] = 1;  tijk[10][3] = 1.7;   cijk[10][3] = 0;  eijk[10][3] = 0;   bijk[10][3] = 0;   gijk[10][3] = 0;   nijk[10][3] = 4.7859131465806;
    dijk[10][4] = 2;  tijk[10][4] = 0.25;  cijk[10][4] = 0;  eijk[10][4] = 0;   bijk[10][4] = 0;   gijk[10][4] = 0;   nijk[10][4] = -0.73265392369587;
    dijk[10][5] = 2;  tijk[10][5] = 1.35;  cijk[10][5] = 0;  eijk[10][5] = 0;   bijk[10][5] = 0;   gijk[10][5] = 0;   nijk[10][5] = 1.3805471345312;
    dijk[10][6] = 3;  tijk[10][6] = 0;     cijk[10][6] = 0;  eijk[10][6] = 0;   bijk[10][6] = 0;   gijk[10][6] = 0;   nijk[10][6] = 0.28349603476365;
    dijk[10][7] = 3;  tijk[10][7] = 1.25;  cijk[10][7] = 0;  eijk[10][7] = 0;   bijk[10][7] = 0;   gijk[10][7] = 0;   nijk[10][7] = -0.49087385940425;
    dijk[10][8] = 4;  tijk[10][8] = 0;     cijk[10][8] = 0;  eijk[10][8] = 0;   bijk[10][8] = 0;   gijk[10][8] = 0;   nijk[10][8] = -0.10291888921447;
    dijk[10][9] = 4;  tijk[10][9] = 0.7;   cijk[10][9] = 0;  eijk[10][9] = 0;   bijk[10][9] = 0;   gijk[10][9] = 0;   nijk[10][9] = 0.11836314681968;
    dijk[10][10] = 4; tijk[10][10] = 5.4;  cijk[10][10] = 0; eijk[10][10] = 0;  bijk[10][10] = 0;  gijk[10][10] = 0;  nijk[10][10] = 5.5527385721943E-05;
    //Generalized parameters
    fij[1][2] = 1;                //Methane-Nitrogen
    fij[1][3] = 1;                //Methane-CO2
    fij[1][4] = 1;                //Methane-Ethane
    fij[1][5] = 1;                //Methane-Propane
    fij[2][3] = 1;                //Nitrogen-CO2
    fij[2][4] = 1;                //Nitrogen-Ethane
    fij[1][15] = 1;               //Methane-Hydrogen
    fij[1][6] = 0.771035405688;   //Methane-Isobutane
    fij[1][7] = 1;                //Methane-n-Butane
    fij[4][5] = 0.13042476515;    //Ethane-Propane
    fij[4][6] = 0.260632376098;   //Ethane-Isobutane
    fij[4][7] = 0.281570073085;   //Ethane-n-Butane
    fij[5][6] = -0.0551609771024; //Propane-Isobutane
    fij[5][7] = 0.0312572600489;  //Propane-n-Butane
    fij[6][7] = -0.0551240293009; //Isobutane-n-Butane
    //Model numbers for binary mixtures with no excess functions (mn=-1)
    for (i = 1 ; i<= MaxFlds; i++){
      mNumb[i][i] = -1;
      for (j = i + 1 ; j<= MaxFlds; j++){
        fij[j][i] = fij[i][j];
        mNumb[i][j] = -1;  
        mNumb[j][i] = -1;
      }
    }
    //Model numbers for excess functions, 10 is for generalized equation
    mNumb[1][2] = 3;
    mNumb[1][3] = 4;
    mNumb[1][4] = 1;
    mNumb[1][5] = 2;
    mNumb[1][6] = 10;
    mNumb[1][7] = 10;
    mNumb[1][15] = 7;
    mNumb[2][3] = 5;
    mNumb[2][4] = 6;
    mNumb[4][5] = 10;
    mNumb[4][6] = 10;
    mNumb[4][7] = 10;
    mNumb[5][6] = 10;
    mNumb[5][7] = 10;
    mNumb[6][7] = 10;
    //Ideal gas parameters
    n0i[1][3] = 4.00088;  n0i[1][4] = 0.76315;  n0i[1][5] = 0.0046;   n0i[1][6] = 8.74432;  n0i[1][7] = -4.46921; n0i[1][1] = 29.83843397;  n0i[1][2] = -15999.69151;
    n0i[2][3] = 3.50031;  n0i[2][4] = 0.13732;  n0i[2][5] = -0.1466;  n0i[2][6] = 0.90066;  n0i[2][7] = 0;        n0i[2][1] = 17.56770785;  n0i[2][2] = -2801.729072;
    n0i[3][3] = 3.50002;  n0i[3][4] = 2.04452;  n0i[3][5] = -1.06044; n0i[3][6] = 2.03366;  n0i[3][7] = 0.01393;  n0i[3][1] = 20.65844696;  n0i[3][2] = -4902.171516;
    n0i[4][3] = 4.00263;  n0i[4][4] = 4.33939;  n0i[4][5] = 1.23722;  n0i[4][6] = 13.1974;  n0i[4][7] = -6.01989; n0i[4][1] = 36.73005938;  n0i[4][2] = -23639.65301;
    n0i[5][3] = 4.02939;  n0i[5][4] = 6.60569;  n0i[5][5] = 3.197;    n0i[5][6] = 19.1921;  n0i[5][7] = -8.37267; n0i[5][1] = 44.70909619;  n0i[5][2] = -31236.63551;
    n0i[6][3] = 4.06714;  n0i[6][4] = 8.97575;  n0i[6][5] = 5.25156;  n0i[6][6] = 25.1423;  n0i[6][7] = 16.1388;  n0i[6][1] = 34.30180349;  n0i[6][2] = -38525.50276;
    n0i[7][3] = 4.33944;  n0i[7][4] = 9.44893;  n0i[7][5] = 6.89406;  n0i[7][6] = 24.4618;  n0i[7][7] = 14.7824;  n0i[7][1] = 36.53237783;  n0i[7][2] = -38957.80933;
    n0i[8][3] = 4;        n0i[8][4] = 11.7618;  n0i[8][5] = 20.1101;  n0i[8][6] = 33.1688;  n0i[8][7] = 0;        n0i[8][1] = 43.17218626;  n0i[8][2] = -51198.30946;
    n0i[9][3] = 4;        n0i[9][4] = 8.95043;  n0i[9][5] = 21.836;   n0i[9][6] = 33.4032;  n0i[9][7] = 0;        n0i[9][1] = 42.67837089;  n0i[9][2] = -45215.83;
    n0i[10][3] = 4;       n0i[10][4] = 11.6977; n0i[10][5] = 26.8142; n0i[10][6] = 38.6164; n0i[10][7] = 0;       n0i[10][1] = 46.99717188; n0i[10][2] = -52746.83318;
    n0i[11][3] = 4;       n0i[11][4] = 13.7266; n0i[11][5] = 30.4707; n0i[11][6] = 43.5561; n0i[11][7] = 0;       n0i[11][1] = 52.07631631; n0i[11][2] = -57104.81056;
    n0i[12][3] = 4;       n0i[12][4] = 15.6865; n0i[12][5] = 33.8029; n0i[12][6] = 48.1731; n0i[12][7] = 0;       n0i[12][1] = 57.25830934; n0i[12][2] = -60546.76385;
    n0i[13][3] = 4;       n0i[13][4] = 18.0241; n0i[13][5] = 38.1235; n0i[13][6] = 53.3415; n0i[13][7] = 0;       n0i[13][1] = 62.09646901; n0i[13][2] = -66600.12837;
    n0i[14][3] = 4;       n0i[14][4] = 21.0069; n0i[14][5] = 43.4931; n0i[14][6] = 58.3657; n0i[14][7] = 0;       n0i[14][1] = 65.93909154; n0i[14][2] = -74131.45483;
    n0i[15][3] = 2.47906; n0i[15][4] = 0.95806; n0i[15][5] = 0.45444; n0i[15][6] = 1.56039; n0i[15][7] = -1.3756; n0i[15][1] = 13.07520288; n0i[15][2] = -5836.943696;
    n0i[16][3] = 3.50146; n0i[16][4] = 1.07558; n0i[16][5] = 1.01334; n0i[16][6] = 0;       n0i[16][7] = 0;       n0i[16][1] = 16.8017173;  n0i[16][2] = -2318.32269;
    n0i[17][3] = 3.50055; n0i[17][4] = 1.02865; n0i[17][5] = 0.00493; n0i[17][6] = 0;       n0i[17][7] = 0;       n0i[17][1] = 17.45786899; n0i[17][2] = -2635.244116;
    n0i[18][3] = 4.00392; n0i[18][4] = 0.01059; n0i[18][5] = 0.98763; n0i[18][6] = 3.06904; n0i[18][7] = 0;       n0i[18][1] = 21.57882705; n0i[18][2] = -7766.733078;
    n0i[19][3] = 4;       n0i[19][4] = 3.11942; n0i[19][5] = 1.00243; n0i[19][6] = 0;       n0i[19][7] = 0;       n0i[19][1] = 21.5830944;  n0i[19][2] = -6069.035869;
    n0i[20][3] = 2.5;     n0i[20][4] = 0;       n0i[20][5] = 0;       n0i[20][6] = 0;       n0i[20][7] = 0;       n0i[20][1] = 10.04639507; n0i[20][2] = -745.375;
    n0i[21][3] = 2.5;     n0i[21][4] = 0;       n0i[21][5] = 0;       n0i[21][6] = 0;       n0i[21][7] = 0;       n0i[21][1] = 10.04639507; n0i[21][2] = -745.375;

    th0i[1][4] = 820.659;  th0i[1][5] = 178.41;   th0i[1][6] = 1062.82;  th0i[1][7] = 1090.53;
    th0i[2][4] = 662.738;  th0i[2][5] = 680.562;  th0i[2][6] = 1740.06;  th0i[2][7] = 0;
    th0i[3][4] = 919.306;  th0i[3][5] = 865.07;   th0i[3][6] = 483.553;  th0i[3][7] = 341.109;
    th0i[4][4] = 559.314;  th0i[4][5] = 223.284;  th0i[4][6] = 1031.38;  th0i[4][7] = 1071.29;
    th0i[5][4] = 479.856;  th0i[5][5] = 200.893;  th0i[5][6] = 955.312;  th0i[5][7] = 1027.29;
    th0i[6][4] = 438.27;   th0i[6][5] = 198.018;  th0i[6][6] = 1905.02;  th0i[6][7] = 893.765;
    th0i[7][4] = 468.27;   th0i[7][5] = 183.636;  th0i[7][6] = 1914.1;   th0i[7][7] = 903.185;
    th0i[8][4] = 292.503;  th0i[8][5] = 910.237;  th0i[8][6] = 1919.37;  th0i[8][7] = 0;
    th0i[9][4] = 178.67;   th0i[9][5] = 840.538;  th0i[9][6] = 1774.25;  th0i[9][7] = 0;
    th0i[10][4] = 182.326; th0i[10][5] = 859.207; th0i[10][6] = 1826.59; th0i[10][7] = 0;
    th0i[11][4] = 169.789; th0i[11][5] = 836.195; th0i[11][6] = 1760.46; th0i[11][7] = 0;
    th0i[12][4] = 158.922; th0i[12][5] = 815.064; th0i[12][6] = 1693.07; th0i[12][7] = 0;
    th0i[13][4] = 156.854; th0i[13][5] = 814.882; th0i[13][6] = 1693.79; th0i[13][7] = 0;
    th0i[14][4] = 164.947; th0i[14][5] = 836.264; th0i[14][6] = 1750.24; th0i[14][7] = 0;
    th0i[15][4] = 228.734; th0i[15][5] = 326.843; th0i[15][6] = 1651.71; th0i[15][7] = 1671.69;
    th0i[16][4] = 2235.71; th0i[16][5] = 1116.69; th0i[16][6] = 0;       th0i[16][7] = 0;
    th0i[17][4] = 1550.45; th0i[17][5] = 704.525; th0i[17][6] = 0;       th0i[17][7] = 0;
    th0i[18][4] = 268.795; th0i[18][5] = 1141.41; th0i[18][6] = 2507.37; th0i[18][7] = 0;
    th0i[19][4] = 1833.63; th0i[19][5] = 847.181; th0i[19][6] = 0;       th0i[19][7] = 0;
    th0i[20][4] = 0;       th0i[20][5] = 0;       th0i[20][6] = 0;       th0i[20][7] = 0;
    th0i[21][4] = 0;       th0i[21][5] = 0;       th0i[21][6] = 0;       th0i[21][7] = 0;
    
    //Mixture parameters for reducing variables
    bvij[1][2] = 0.998721377;   gvij[1][2] = 1.013950311;   btij[1][2] = 0.99809883;    gtij[1][2] = 0.979273013;   //CH4-N2
    bvij[1][3] = 0.999518072;   gvij[1][3] = 1.002806594;   btij[1][3] = 1.02262449;    gtij[1][3] = 0.975665369;   //CH4-CO2
    bvij[1][4] = 0.997547866;   gvij[1][4] = 1.006617867;   btij[1][4] = 0.996336508;   gtij[1][4] = 1.049707697;   //CH4-C2H6
    bvij[1][5] = 1.00482707;    gvij[1][5] = 1.038470657;   btij[1][5] = 0.989680305;   gtij[1][5] = 1.098655531;   //CH4-C3H8
    bvij[1][6] = 1.011240388;   gvij[1][6] = 1.054319053;   btij[1][6] = 0.980315756;   gtij[1][6] = 1.161117729;   //CH4-i-C4H10
    bvij[1][7] = 0.979105972;   gvij[1][7] = 1.045375122;   btij[1][7] = 0.99417491;    gtij[1][7] = 1.171607691;   //CH4-C4H10
    bvij[1][8] = 1;             gvij[1][8] = 1.343685343;   btij[1][8] = 1;             gtij[1][8] = 1.188899743;   //CH4-i-C5H12
    bvij[1][9] = 0.94833012;    gvij[1][9] = 1.124508039;   btij[1][9] = 0.992127525;   gtij[1][9] = 1.249173968;   //CH4-C5H12
    bvij[1][10] = 0.958015294;  gvij[1][10] = 1.052643846;  btij[1][10] = 0.981844797;  gtij[1][10] = 1.330570181;  //CH4-C6H14
    bvij[1][11] = 0.962050831;  gvij[1][11] = 1.156655935;  btij[1][11] = 0.977431529;  gtij[1][11] = 1.379850328;  //CH4-C7H16
    bvij[1][12] = 0.994740603;  gvij[1][12] = 1.116549372;  btij[1][12] = 0.957473785;  gtij[1][12] = 1.449245409;  //CH4-C8H18
    bvij[1][13] = 1.002852287;  gvij[1][13] = 1.141895355;  btij[1][13] = 0.947716769;  gtij[1][13] = 1.528532478;  //CH4-C9H20
    bvij[1][14] = 1.033086292;  gvij[1][14] = 1.146089637;  btij[1][14] = 0.937777823;  gtij[1][14] = 1.568231489;  //CH4-C10H22
    bvij[1][15] = 1;            gvij[1][15] = 1.018702573;  btij[1][15] = 1;            gtij[1][15] = 1.352643115;  //CH4-H2
    bvij[1][16] = 1;            gvij[1][16] = 1;            btij[1][16] = 1;            gtij[1][16] = 0.95;         //CH4-O2
    bvij[1][17] = 0.997340772;  gvij[1][17] = 1.006102927;  btij[1][17] = 0.987411732;  gtij[1][17] = 0.987473033;  //CH4-CO
    bvij[1][18] = 1.012783169;  gvij[1][18] = 1.585018334;  btij[1][18] = 1.063333913;  gtij[1][18] = 0.775810513;  //CH4-H2O
    bvij[1][19] = 1.012599087;  gvij[1][19] = 1.040161207;  btij[1][19] = 1.011090031;  gtij[1][19] = 0.961155729;  //CH4-H2S
    bvij[1][20] = 1;            gvij[1][20] = 0.881405683;  btij[1][20] = 1;            gtij[1][20] = 3.159776855;  //CH4-He
    bvij[1][21] = 1.034630259;  gvij[1][21] = 1.014678542;  btij[1][21] = 0.990954281;  gtij[1][21] = 0.989843388;  //CH4-Ar
    bvij[2][3] = 0.977794634;   gvij[2][3] = 1.047578256;   btij[2][3] = 1.005894529;   gtij[2][3] = 1.107654104;   //N2-CO2
    bvij[2][4] = 0.978880168;   gvij[2][4] = 1.042352891;   btij[2][4] = 1.007671428;   gtij[2][4] = 1.098650964;   //N2-C2H6
    bvij[2][5] = 0.974424681;   gvij[2][5] = 1.081025408;   btij[2][5] = 1.002677329;   gtij[2][5] = 1.201264026;   //N2-C3H8
    bvij[2][6] = 0.98641583;    gvij[2][6] = 1.100576129;   btij[2][6] = 0.99286813;    gtij[2][6] = 1.284462634;   //N2-i-C4H10
    bvij[2][7] = 0.99608261;    gvij[2][7] = 1.146949309;   btij[2][7] = 0.994515234;   gtij[2][7] = 1.304886838;   //N2-C4H10
    bvij[2][8] = 1;             gvij[2][8] = 1.154135439;   btij[2][8] = 1;             gtij[2][8] = 1.38177077;    //N2-i-C5H12
    bvij[2][9] = 1;             gvij[2][9] = 1.078877166;   btij[2][9] = 1;             gtij[2][9] = 1.419029041;   //N2-C5H12
    bvij[2][10] = 1;            gvij[2][10] = 1.195952177;  btij[2][10] = 1;            gtij[2][10] = 1.472607971;  //N2-C6H14
    bvij[2][11] = 1;            gvij[2][11] = 1.40455409;   btij[2][11] = 1;            gtij[2][11] = 1.520975334;  //N2-C7H16
    bvij[2][12] = 1;            gvij[2][12] = 1.186067025;  btij[2][12] = 1;            gtij[2][12] = 1.733280051;  //N2-C8H18
    bvij[2][13] = 1;            gvij[2][13] = 1.100405929;  btij[2][13] = 0.95637945;   gtij[2][13] = 1.749119996;  //N2-C9H20
    bvij[2][14] = 1;            gvij[2][14] = 1;            btij[2][14] = 0.957934447;  gtij[2][14] = 1.822157123;  //N2-C10H22
    bvij[2][15] = 0.972532065;  gvij[2][15] = 0.970115357;  btij[2][15] = 0.946134337;  gtij[2][15] = 1.175696583;  //N2-H2
    bvij[2][16] = 0.99952177;   gvij[2][16] = 0.997082328;  btij[2][16] = 0.997190589;  gtij[2][16] = 0.995157044;  //N2-O2
    bvij[2][17] = 1;            gvij[2][17] = 1.008690943;  btij[2][17] = 1;            gtij[2][17] = 0.993425388;  //N2-CO
    bvij[2][18] = 1;            gvij[2][18] = 1.094749685;  btij[2][18] = 1;            gtij[2][18] = 0.968808467;  //N2-H2O
    bvij[2][19] = 0.910394249;  gvij[2][19] = 1.256844157;  btij[2][19] = 1.004692366;  gtij[2][19] = 0.9601742;    //N2-H2S
    bvij[2][20] = 0.969501055;  gvij[2][20] = 0.932629867;  btij[2][20] = 0.692868765;  gtij[2][20] = 1.47183158;   //N2-He
    bvij[2][21] = 1.004166412;  gvij[2][21] = 1.002212182;  btij[2][21] = 0.999069843;  gtij[2][21] = 0.990034831;  //N2-Ar
    bvij[3][4] = 1.002525718;   gvij[3][4] = 1.032876701;   btij[3][4] = 1.013871147;   gtij[3][4] = 0.90094953;    //CO2-C2H6
    bvij[3][5] = 0.996898004;   gvij[3][5] = 1.047596298;   btij[3][5] = 1.033620538;   gtij[3][5] = 0.908772477;   //CO2-C3H8
    bvij[3][6] = 1.076551882;   gvij[3][6] = 1.081909003;   btij[3][6] = 1.023339824;   gtij[3][6] = 0.929982936;   //CO2-i-C4H10
    bvij[3][7] = 1.174760923;   gvij[3][7] = 1.222437324;   btij[3][7] = 1.018171004;   gtij[3][7] = 0.911498231;   //CO2-C4H10
    bvij[3][8] = 1.060793104;   gvij[3][8] = 1.116793198;   btij[3][8] = 1.019180957;   gtij[3][8] = 0.961218039;   //CO2-i-C5H12
    bvij[3][9] = 1.024311498;   gvij[3][9] = 1.068406078;   btij[3][9] = 1.027000795;   gtij[3][9] = 0.979217302;   //CO2-C5H12
    bvij[3][10] = 1;            gvij[3][10] = 0.851343711;  btij[3][10] = 1;            gtij[3][10] = 1.038675574;  //CO2-C6H14
    bvij[3][11] = 1.205469976;  gvij[3][11] = 1.164585914;  btij[3][11] = 1.011806317;  gtij[3][11] = 1.046169823;  //CO2-C7H16
    bvij[3][12] = 1.026169373;  gvij[3][12] = 1.104043935;  btij[3][12] = 1.02969078;   gtij[3][12] = 1.074455386;  //CO2-C8H18
    bvij[3][13] = 1;            gvij[3][13] = 0.973386152;  btij[3][13] = 1.00768862;   gtij[3][13] = 1.140671202;  //CO2-C9H20
    bvij[3][14] = 1.000151132;  gvij[3][14] = 1.183394668;  btij[3][14] = 1.02002879;   gtij[3][14] = 1.145512213;  //CO2-C10H22
    bvij[3][15] = 0.904142159;  gvij[3][15] = 1.15279255;   btij[3][15] = 0.942320195;  gtij[3][15] = 1.782924792;  //CO2-H2
    bvij[3][16] = 1;            gvij[3][16] = 1;            btij[3][16] = 1;            gtij[3][16] = 1;            //CO2-O2
    bvij[3][17] = 1;            gvij[3][17] = 1;            btij[3][17] = 1;            gtij[3][17] = 1;            //CO2-CO
    bvij[3][18] = 0.949055959;  gvij[3][18] = 1.542328793;  btij[3][18] = 0.997372205;  gtij[3][18] = 0.775453996;  //CO2-H2O
    bvij[3][19] = 0.906630564;  gvij[3][19] = 1.024085837;  btij[3][19] = 1.016034583;  gtij[3][19] = 0.92601888;   //CO2-H2S
    bvij[3][20] = 0.846647561;  gvij[3][20] = 0.864141549;  btij[3][20] = 0.76837763;   gtij[3][20] = 3.207456948;  //CO2-He
    bvij[3][21] = 1.008392428;  gvij[3][21] = 1.029205465;  btij[3][21] = 0.996512863;  gtij[3][21] = 1.050971635;  //CO2-Ar
    bvij[4][5] = 0.997607277;   gvij[4][5] = 1.00303472;    btij[4][5] = 0.996199694;   gtij[4][5] = 1.01473019;    //C2H6-C3H8
    bvij[4][6] = 1;             gvij[4][6] = 1.006616886;   btij[4][6] = 1;             gtij[4][6] = 1.033283811;   //C2H6-i-C4H10
    bvij[4][7] = 0.999157205;   gvij[4][7] = 1.006179146;   btij[4][7] = 0.999130554;   gtij[4][7] = 1.034832749;   //C2H6-C4H10
    bvij[4][8] = 1;             gvij[4][8] = 1.045439935;   btij[4][8] = 1;             gtij[4][8] = 1.021150247;   //C2H6-i-C5H12
    bvij[4][9] = 0.993851009;   gvij[4][9] = 1.026085655;   btij[4][9] = 0.998688946;   gtij[4][9] = 1.066665676;   //C2H6-C5H12
    bvij[4][10] = 1;            gvij[4][10] = 1.169701102;  btij[4][10] = 1;            gtij[4][10] = 1.092177796;  //C2H6-C6H14
    bvij[4][11] = 1;            gvij[4][11] = 1.057666085;  btij[4][11] = 1;            gtij[4][11] = 1.134532014;  //C2H6-C7H16
    bvij[4][12] = 1.007469726;  gvij[4][12] = 1.071917985;  btij[4][12] = 0.984068272;  gtij[4][12] = 1.168636194;  //C2H6-C8H18
    bvij[4][13] = 1;            gvij[4][13] = 1.14353473;   btij[4][13] = 1;            gtij[4][13] = 1.05603303;   //C2H6-C9H20
    bvij[4][14] = 0.995676258;  gvij[4][14] = 1.098361281;  btij[4][14] = 0.970918061;  gtij[4][14] = 1.237191558;  //C2H6-C10H22
    bvij[4][15] = 0.925367171;  gvij[4][15] = 1.10607204;   btij[4][15] = 0.932969831;  gtij[4][15] = 1.902008495;  //C2H6-H2
    bvij[4][16] = 1;            gvij[4][16] = 1;            btij[4][16] = 1;            gtij[4][16] = 1;            //C2H6-O2
    bvij[4][17] = 1;            gvij[4][17] = 1.201417898;  btij[4][17] = 1;            gtij[4][17] = 1.069224728;  //C2H6-CO
    bvij[4][18] = 1;            gvij[4][18] = 1;            btij[4][18] = 1;            gtij[4][18] = 1;            //C2H6-H2O
    bvij[4][19] = 1.010817909;  gvij[4][19] = 1.030988277;  btij[4][19] = 0.990197354;  gtij[4][19] = 0.90273666;   //C2H6-H2S
    bvij[4][20] = 1;            gvij[4][20] = 1;            btij[4][20] = 1;            gtij[4][20] = 1;            //C2H6-He
    bvij[4][21] = 1;            gvij[4][21] = 1;            btij[4][21] = 1;            gtij[4][21] = 1;            //C2H6-Ar
    bvij[5][6] = 0.999243146;   gvij[5][6] = 1.001156119;   btij[5][6] = 0.998012298;   gtij[5][6] = 1.005250774;   //C3H8-i-C4H10
    bvij[5][7] = 0.999795868;   gvij[5][7] = 1.003264179;   btij[5][7] = 1.000310289;   gtij[5][7] = 1.007392782;   //C3H8-C4H10
    bvij[5][8] = 1.040459289;   gvij[5][8] = 0.999432118;   btij[5][8] = 0.994364425;   gtij[5][8] = 1.0032695;     //C3H8-i-C5H12
    bvij[5][9] = 1.044919431;   gvij[5][9] = 1.019921513;   btij[5][9] = 0.996484021;   gtij[5][9] = 1.008344412;   //C3H8-C5H12
    bvij[5][10] = 1;            gvij[5][10] = 1.057872566;  btij[5][10] = 1;            gtij[5][10] = 1.025657518;  //C3H8-C6H14
    bvij[5][11] = 1;            gvij[5][11] = 1.079648053;  btij[5][11] = 1;            gtij[5][11] = 1.050044169;  //C3H8-C7H16
    bvij[5][12] = 1;            gvij[5][12] = 1.102764612;  btij[5][12] = 1;            gtij[5][12] = 1.063694129;  //C3H8-C8H18
    bvij[5][13] = 1;            gvij[5][13] = 1.199769134;  btij[5][13] = 1;            gtij[5][13] = 1.109973833;  //C3H8-C9H20
    bvij[5][14] = 0.984104227;  gvij[5][14] = 1.053040574;  btij[5][14] = 0.985331233;  gtij[5][14] = 1.140905252;  //C3H8-C10H22
    bvij[5][15] = 1;            gvij[5][15] = 1.07400611;   btij[5][15] = 1;            gtij[5][15] = 2.308215191;  //C3H8-H2
    bvij[5][16] = 1;            gvij[5][16] = 1;            btij[5][16] = 1;            gtij[5][16] = 1;            //C3H8-O2
    bvij[5][17] = 1;            gvij[5][17] = 1.108143673;  btij[5][17] = 1;            gtij[5][17] = 1.197564208;  //C3H8-CO
    bvij[5][18] = 1;            gvij[5][18] = 1.011759763;  btij[5][18] = 1;            gtij[5][18] = 0.600340961;  //C3H8-H2O
    bvij[5][19] = 0.936811219;  gvij[5][19] = 1.010593999;  btij[5][19] = 0.992573556;  gtij[5][19] = 0.905829247;  //C3H8-H2S
    bvij[5][20] = 1;            gvij[5][20] = 1;            btij[5][20] = 1;            gtij[5][20] = 1;            //C3H8-He
    bvij[5][21] = 1;            gvij[5][21] = 1;            btij[5][21] = 1;            gtij[5][21] = 1;            //C3H8-Ar
    //The beta values for isobutane+butane are the reciprocal values of those in the GERG-2008 publication because the order was reversed in this work.
    bvij[6][7] = 0.999120311;   gvij[6][7] = 1.00041444;    btij[6][7] = 0.999922459;   gtij[6][7] = 1.001432824;   //C4H10-i-C4H10
    bvij[6][8] = 1;             gvij[6][8] = 1.002284353;   btij[6][8] = 1;             gtij[6][8] = 1.001835788;   //i-C4H10-i-C5H1
    bvij[6][9] = 1;             gvij[6][9] = 1.002779804;   btij[6][9] = 1;             gtij[6][9] = 1.002495889;   //i-C4H10-C5H12
    bvij[6][10] = 1;            gvij[6][10] = 1.010493989;  btij[6][10] = 1;            gtij[6][10] = 1.006018054;  //i-C4H10-C6H14
    bvij[6][11] = 1;            gvij[6][11] = 1.021668316;  btij[6][11] = 1;            gtij[6][11] = 1.00988576;   //i-C4H10-C7H16
    bvij[6][12] = 1;            gvij[6][12] = 1.032807063;  btij[6][12] = 1;            gtij[6][12] = 1.013945424;  //i-C4H10-C8H18
    bvij[6][13] = 1;            gvij[6][13] = 1.047298475;  btij[6][13] = 1;            gtij[6][13] = 1.017817492;  //i-C4H10-C9H20
    bvij[6][14] = 1;            gvij[6][14] = 1.060243344;  btij[6][14] = 1;            gtij[6][14] = 1.021624748;  //i-C4H10-C10H22
    bvij[6][15] = 1;            gvij[6][15] = 1.147595688;  btij[6][15] = 1;            gtij[6][15] = 1.895305393;  //i-C4H10-H2
    bvij[6][16] = 1;            gvij[6][16] = 1;            btij[6][16] = 1;            gtij[6][16] = 1;            //i-C4H10-O2
    bvij[6][17] = 1;            gvij[6][17] = 1.087272232;  btij[6][17] = 1;            gtij[6][17] = 1.161390082;  //i-C4H10-CO
    bvij[6][18] = 1;            gvij[6][18] = 1;            btij[6][18] = 1;            gtij[6][18] = 1;            //i-C4H10-H2O
    bvij[6][19] = 1.012994431;  gvij[6][19] = 0.988591117;  btij[6][19] = 0.974550548;  gtij[6][19] = 0.937130844;  //i-C4H10-H2S
    bvij[6][20] = 1;            gvij[6][20] = 1;            btij[6][20] = 1;            gtij[6][20] = 1;            //i-C4H10-He
    bvij[6][21] = 1;            gvij[6][21] = 1;            btij[6][21] = 1;            gtij[6][21] = 1;            //i-C4H10-Ar
    bvij[7][8] = 1;             gvij[7][8] = 1.002728434;   btij[7][8] = 1;             gtij[7][8] = 1.000792201;   //C4H10-i-C5H12
    bvij[7][9] = 1;             gvij[7][9] = 1.01815965;    btij[7][9] = 1;             gtij[7][9] = 1.00214364;    //C4H10-C5H12
    bvij[7][10] = 1;            gvij[7][10] = 1.034995284;  btij[7][10] = 1;            gtij[7][10] = 1.00915706;   //C4H10-C6H14
    bvij[7][11] = 1;            gvij[7][11] = 1.019174227;  btij[7][11] = 1;            gtij[7][11] = 1.021283378;  //C4H10-C7H16
    bvij[7][12] = 1;            gvij[7][12] = 1.046905515;  btij[7][12] = 1;            gtij[7][12] = 1.033180106;  //C4H10-C8H18
    bvij[7][13] = 1;            gvij[7][13] = 1.049219137;  btij[7][13] = 1;            gtij[7][13] = 1.014096448;  //C4H10-C9H20
    bvij[7][14] = 0.976951968;  gvij[7][14] = 1.027845529;  btij[7][14] = 0.993688386;  gtij[7][14] = 1.076466918;  //C4H10-C10H22
    bvij[7][15] = 1;            gvij[7][15] = 1.232939523;  btij[7][15] = 1;            gtij[7][15] = 2.509259945;  //C4H10-H2
    bvij[7][16] = 1;            gvij[7][16] = 1;            btij[7][16] = 1;            gtij[7][16] = 1;            //C4H10-O2
    bvij[7][17] = 1;            gvij[7][17] = 1.084740904;  btij[7][17] = 1;            gtij[7][17] = 1.173916162;  //C4H10-CO
    bvij[7][18] = 1;            gvij[7][18] = 1.223638763;  btij[7][18] = 1;            gtij[7][18] = 0.615512682;  //C4H10-H2O
    bvij[7][19] = 0.908113163;  gvij[7][19] = 1.033366041;  btij[7][19] = 0.985962886;  gtij[7][19] = 0.926156602;  //C4H10-H2S
    bvij[7][20] = 1;            gvij[7][20] = 1;            btij[7][20] = 1;            gtij[7][20] = 1;            //C4H10-He
    bvij[7][21] = 1;            gvij[7][21] = 1.214638734;  btij[7][21] = 1;            gtij[7][21] = 1.245039498;  //C4H10-Ar
    bvij[8][9] = 1;             gvij[8][9] = 1.000024335;   btij[8][9] = 1;             gtij[8][9] = 1.000050537;   //C5H12-i-C5H12
    bvij[8][10] = 1;            gvij[8][10] = 1.002995876;  btij[8][10] = 1;            gtij[8][10] = 1.001204174;  //i-C5H12-C6H14
    bvij[8][11] = 1;            gvij[8][11] = 1.009928206;  btij[8][11] = 1;            gtij[8][11] = 1.003194615;  //i-C5H12-C7H16
    bvij[8][12] = 1;            gvij[8][12] = 1.017880545;  btij[8][12] = 1;            gtij[8][12] = 1.00564748;   //i-C5H12-C8H18
    bvij[8][13] = 1;            gvij[8][13] = 1.028994325;  btij[8][13] = 1;            gtij[8][13] = 1.008191499;  //i-C5H12-C9H20
    bvij[8][14] = 1;            gvij[8][14] = 1.039372957;  btij[8][14] = 1;            gtij[8][14] = 1.010825138;  //i-C5H12-C10H22
    bvij[8][15] = 1;            gvij[8][15] = 1.184340443;  btij[8][15] = 1;            gtij[8][15] = 1.996386669;  //i-C5H12-H2
    bvij[8][16] = 1;            gvij[8][16] = 1;            btij[8][16] = 1;            gtij[8][16] = 1;            //i-C5H12-O2
    bvij[8][17] = 1;            gvij[8][17] = 1.116694577;  btij[8][17] = 1;            gtij[8][17] = 1.199326059;  //i-C5H12-CO
    bvij[8][18] = 1;            gvij[8][18] = 1;            btij[8][18] = 1;            gtij[8][18] = 1;            //i-C5H12-H2O
    bvij[8][19] = 1;            gvij[8][19] = 0.835763343;  btij[8][19] = 1;            gtij[8][19] = 0.982651529;  //i-C5H12-H2S
    bvij[8][20] = 1;            gvij[8][20] = 1;            btij[8][20] = 1;            gtij[8][20] = 1;            //i-C5H12-He
    bvij[8][21] = 1;            gvij[8][21] = 1;            btij[8][21] = 1;            gtij[8][21] = 1;            //i-C5H12-Ar
    bvij[9][10] = 1;            gvij[9][10] = 1.002480637;  btij[9][10] = 1;            gtij[9][10] = 1.000761237;  //C5H12-C6H14
    bvij[9][11] = 1;            gvij[9][11] = 1.008972412;  btij[9][11] = 1;            gtij[9][11] = 1.002441051;  //C5H12-C7H16
    bvij[9][12] = 1;            gvij[9][12] = 1.069223964;  btij[9][12] = 1;            gtij[9][12] = 1.016422347;  //C5H12-C8H18
    bvij[9][13] = 1;            gvij[9][13] = 1.034910633;  btij[9][13] = 1;            gtij[9][13] = 1.103421755;  //C5H12-C9H20
    bvij[9][14] = 1;            gvij[9][14] = 1.016370338;  btij[9][14] = 1;            gtij[9][14] = 1.049035838;  //C5H12-C10H22
    bvij[9][15] = 1;            gvij[9][15] = 1.188334783;  btij[9][15] = 1;            gtij[9][15] = 2.013859174;  //C5H12-H2
    bvij[9][16] = 1;            gvij[9][16] = 1;            btij[9][16] = 1;            gtij[9][16] = 1;            //C5H12-O2
    bvij[9][17] = 1;            gvij[9][17] = 1.119954454;  btij[9][17] = 1;            gtij[9][17] = 1.206043295;  //C5H12-CO
    bvij[9][18] = 1;            gvij[9][18] = 0.95667731;   btij[9][18] = 1;            gtij[9][18] = 0.447666011;  //C5H12-H2O
    bvij[9][19] = 0.984613203;  gvij[9][19] = 1.076539234;  btij[9][19] = 0.962006651;  gtij[9][19] = 0.959065662;  //C5H12-H2S
    bvij[9][20] = 1;            gvij[9][20] = 1;            btij[9][20] = 1;            gtij[9][20] = 1;            //C5H12-He
    bvij[9][21] = 1;            gvij[9][21] = 1;            btij[9][21] = 1;            gtij[9][21] = 1;            //C5H12-Ar
    bvij[10][11] = 1;           gvij[10][11] = 1.001508227; btij[10][11] = 1;           gtij[10][11] = 0.999762786; //C6H14-C7H16
    bvij[10][12] = 1;           gvij[10][12] = 1.006268954; btij[10][12] = 1;           gtij[10][12] = 1.001633952; //C6H14-C8H18
    bvij[10][13] = 1;           gvij[10][13] = 1.02076168;  btij[10][13] = 1;           gtij[10][13] = 1.055369591; //C6H14-C9H20
    bvij[10][14] = 1.001516371; gvij[10][14] = 1.013511439; btij[10][14] = 0.99764101;  gtij[10][14] = 1.028939539; //C6H14-C10H22
    bvij[10][15] = 1;           gvij[10][15] = 1.243461678; btij[10][15] = 1;           gtij[10][15] = 3.021197546; //C6H14-H2
    bvij[10][16] = 1;           gvij[10][16] = 1;           btij[10][16] = 1;           gtij[10][16] = 1;           //C6H14-O2
    bvij[10][17] = 1;           gvij[10][17] = 1.155145836; btij[10][17] = 1;           gtij[10][17] = 1.233272781; //C6H14-CO
    bvij[10][18] = 1;           gvij[10][18] = 1.170217596; btij[10][18] = 1;           gtij[10][18] = 0.569681333; //C6H14-H2O
    bvij[10][19] = 0.754473958; gvij[10][19] = 1.339283552; btij[10][19] = 0.985891113; gtij[10][19] = 0.956075596; //C6H14-H2S
    bvij[10][20] = 1;           gvij[10][20] = 1;           btij[10][20] = 1;           gtij[10][20] = 1;           //C6H14-He
    bvij[10][21] = 1;           gvij[10][21] = 1;           btij[10][21] = 1;           gtij[10][21] = 1;           //C6H14-Ar
    bvij[11][12] = 1;           gvij[11][12] = 1.006767176; btij[11][12] = 1;           gtij[11][12] = 0.998793111; //C7H16-C8H18
    bvij[11][13] = 1;           gvij[11][13] = 1.001370076; btij[11][13] = 1;           gtij[11][13] = 1.001150096; //C7H16-C9H20
    bvij[11][14] = 1;           gvij[11][14] = 1.002972346; btij[11][14] = 1;           gtij[11][14] = 1.002229938; //C7H16-C10H22
    bvij[11][15] = 1;           gvij[11][15] = 1.159131722; btij[11][15] = 1;           gtij[11][15] = 3.169143057; //C7H16-H2
    bvij[11][16] = 1;           gvij[11][16] = 1;           btij[11][16] = 1;           gtij[11][16] = 1;           //C7H16-O2
    bvij[11][17] = 1;           gvij[11][17] = 1.190354273; btij[11][17] = 1;           gtij[11][17] = 1.256123503; //C7H16-CO
    bvij[11][18] = 1;           gvij[11][18] = 1;           btij[11][18] = 1;           gtij[11][18] = 1;           //C7H16-H2O
    bvij[11][19] = 0.828967164; gvij[11][19] = 1.087956749; btij[11][19] = 0.988937417; gtij[11][19] = 1.013453092; //C7H16-H2S
    bvij[11][20] = 1;           gvij[11][20] = 1;           btij[11][20] = 1;           gtij[11][20] = 1;           //C7H16-He
    bvij[11][21] = 1;           gvij[11][21] = 1;           btij[11][21] = 1;           gtij[11][21] = 1;           //C7H16-Ar
    bvij[12][13] = 1;           gvij[12][13] = 1.001357085; btij[12][13] = 1;           gtij[12][13] = 1.000235044; //C8H18-C9H20
    bvij[12][14] = 1;           gvij[12][14] = 1.002553544; btij[12][14] = 1;           gtij[12][14] = 1.007186267; //C8H18-C10H22
    bvij[12][15] = 1;           gvij[12][15] = 1.305249405; btij[12][15] = 1;           gtij[12][15] = 2.191555216; //C8H18-H2
    bvij[12][16] = 1;           gvij[12][16] = 1;           btij[12][16] = 1;           gtij[12][16] = 1;           //C8H18-O2
    bvij[12][17] = 1;           gvij[12][17] = 1.219206702; btij[12][17] = 1;           gtij[12][17] = 1.276565536; //C8H18-CO
    bvij[12][18] = 1;           gvij[12][18] = 0.599484191; btij[12][18] = 1;           gtij[12][18] = 0.662072469; //C8H18-H2O
    bvij[12][19] = 1;           gvij[12][19] = 1;           btij[12][19] = 1;           gtij[12][19] = 1;           //C8H18-H2S
    bvij[12][20] = 1;           gvij[12][20] = 1;           btij[12][20] = 1;           gtij[12][20] = 1;           //C8H18-He
    bvij[12][21] = 1;           gvij[12][21] = 1;           btij[12][21] = 1;           gtij[12][21] = 1;           //C8H18-Ar
    bvij[13][14] = 1;           gvij[13][14] = 1.00081052;  btij[13][14] = 1;           gtij[13][14] = 1.000182392; //C9H20-C10H22
    bvij[13][15] = 1;           gvij[13][15] = 1.342647661; btij[13][15] = 1;           gtij[13][15] = 2.23435404;  //C9H20-H2
    bvij[13][16] = 1;           gvij[13][16] = 1;           btij[13][16] = 1;           gtij[13][16] = 1;           //C9H20-O2
    bvij[13][17] = 1;           gvij[13][17] = 1.252151449; btij[13][17] = 1;           gtij[13][17] = 1.294070556; //C9H20-CO
    bvij[13][18] = 1;           gvij[13][18] = 1;           btij[13][18] = 1;           gtij[13][18] = 1;           //C9H20-H2O
    bvij[13][19] = 1;           gvij[13][19] = 1.082905109; btij[13][19] = 1;           gtij[13][19] = 1.086557826; //C9H20-H2S
    bvij[13][20] = 1;           gvij[13][20] = 1;           btij[13][20] = 1;           gtij[13][20] = 1;           //C9H20-He
    bvij[13][21] = 1;           gvij[13][21] = 1;           btij[13][21] = 1;           gtij[13][21] = 1;           //C9H20-Ar
    bvij[14][15] = 1.695358382; gvij[14][15] = 1.120233729; btij[14][15] = 1.064818089; gtij[14][15] = 3.786003724; //C10H22-H2
    bvij[14][16] = 1;           gvij[14][16] = 1;           btij[14][16] = 1;           gtij[14][16] = 1;           //C10H22-O2
    bvij[14][17] = 1;           gvij[14][17] = 0.87018496;  btij[14][17] = 1.049594632; gtij[14][17] = 1.803567587; //C10H22-CO
    bvij[14][18] = 1;           gvij[14][18] = 0.551405318; btij[14][18] = 0.897162268; gtij[14][18] = 0.740416402; //C10H22-H2O
    bvij[14][19] = 0.975187766; gvij[14][19] = 1.171714677; btij[14][19] = 0.973091413; gtij[14][19] = 1.103693489; //C10H22-H2S
    bvij[14][20] = 1;           gvij[14][20] = 1;           btij[14][20] = 1;           gtij[14][20] = 1;           //C10H22-He
    bvij[14][21] = 1;           gvij[14][21] = 1;           btij[14][21] = 1;           gtij[14][21] = 1;           //C10H22-Ar
    bvij[15][16] = 1;           gvij[15][16] = 1;           btij[15][16] = 1;           gtij[15][16] = 1;           //H2-O2
    bvij[15][17] = 1;           gvij[15][17] = 1.121416201; btij[15][17] = 1;           gtij[15][17] = 1.377504607; //H2-CO
    bvij[15][18] = 1;           gvij[15][18] = 1;           btij[15][18] = 1;           gtij[15][18] = 1;           //H2-H2O
    bvij[15][19] = 1;           gvij[15][19] = 1;           btij[15][19] = 1;           gtij[15][19] = 1;           //H2-H2S
    bvij[15][20] = 1;           gvij[15][20] = 1;           btij[15][20] = 1;           gtij[15][20] = 1;           //H2-He
    bvij[15][21] = 1;           gvij[15][21] = 1;           btij[15][21] = 1;           gtij[15][21] = 1;           //H2-Ar
    bvij[16][17] = 1;           gvij[16][17] = 1;           btij[16][17] = 1;           gtij[16][17] = 1;           //O2-CO
    bvij[16][18] = 1;           gvij[16][18] = 1.143174289; btij[16][18] = 1;           gtij[16][18] = 0.964767932; //O2-H2O
    bvij[16][19] = 1;           gvij[16][19] = 1;           btij[16][19] = 1;           gtij[16][19] = 1;           //O2-H2S
    bvij[16][20] = 1;           gvij[16][20] = 1;           btij[16][20] = 1;           gtij[16][20] = 1;           //O2-He
    bvij[16][21] = 0.999746847; gvij[16][21] = 0.993907223; btij[16][21] = 1.000023103; gtij[16][21] = 0.990430423; //O2-Ar
    bvij[17][18] = 1;           gvij[17][18] = 1;           btij[17][18] = 1;           gtij[17][18] = 1;           //CO-H2O
    bvij[17][19] = 0.795660392; gvij[17][19] = 1.101731308; btij[17][19] = 1.025536736; gtij[17][19] = 1.022749748; //CO-H2S
    bvij[17][20] = 1;           gvij[17][20] = 1;           btij[17][20] = 1;           gtij[17][20] = 1;           //CO-He
    bvij[17][21] = 1;           gvij[17][21] = 1.159720623; btij[17][21] = 1;           gtij[17][21] = 0.954215746; //CO-Ar
    bvij[18][19] = 1;           gvij[18][19] = 1.014832832; btij[18][19] = 1;           gtij[18][19] = 0.940587083; //H2O-H2S
    bvij[18][20] = 1;           gvij[18][20] = 1;           btij[18][20] = 1;           gtij[18][20] = 1;           //H2O-He
    bvij[18][21] = 1;           gvij[18][21] = 1.038993495; btij[18][21] = 1;           gtij[18][21] = 1.070941866; //H2O-Ar
    bvij[19][20] = 1;           gvij[19][20] = 1;           btij[19][20] = 1;           gtij[19][20] = 1;           //H2S-He
    bvij[19][21] = 1;           gvij[19][21] = 1;           btij[19][21] = 1;           gtij[19][21] = 1;           //H2S-Ar
    bvij[20][21] = 1;           gvij[20][21] = 1;           btij[20][21] = 1;           gtij[20][21] = 1;           //He-Ar
    for (let i = 1 ; i <= MaxFlds; i++){
      bvij[i][i] = 1;
      btij[i][i] = 1;
      gvij[i][i] = 1 / Dc[i];
      gtij[i][i] = Tc[i];
      for (let j = i + 1 ; j <= MaxFlds; j++){
        gvij[i][j] = gvij[i][j] * bvij[i][j] * Math.pow((Vc3[i] + Vc3[j]), 3);
        gtij[i][j] = gtij[i][j] * btij[i][j] * Tc2[i] * Tc2[j];
        bvij[i][j] = Math.pow(bvij[i][j] , 2);
        btij[i][j] = Math.pow(btij[i][j] , 2);
      }
    }
    for (i = 1 ; i<=MaxMdl; i++){
      for (j = 1 ; j<=MaxTrmM; j++){
        gijk[i][j] = -cijk[i][j] * Math.pow(eijk[i][j],2) + bijk[i][j] * gijk[i][j];
        eijk[i][j] = 2 * cijk[i][j] * eijk[i][j] - bijk[i][j];
        cijk[i][j] = -cijk[i][j];
      }
    }
    //Ideal gas terms
    T0 = 298.15;
    d0 = 101.325 / RGERG / T0;
    for (i = 1 ; i <= MaxFlds; i++){
      n0i[i][3] = n0i[i][3] - 1;
      n0i[i][2] = n0i[i][2] + T0;
      for (j = 1 ; j <= 7; j++){n0i[i][j] = Rsr * n0i[i][j]}
      n0i[i][2] = n0i[i][2] - T0;
      n0i[i][1] = n0i[i][1] - Math.log(d0);
    }
    return;
    //Code to produce nearly exact values for n0(1) and n0(2)
    //This is not called in the current code, but included below to show how the values were calculated.  The Exit Sub above can be removed to call this code.
    T0 = 298.15;
    d0 = 101.325 / RGERG / T0;
    for (i = 1 ; i <= MaxFlds; i++){
      n1 = 0; n2 = 0;
      if (th0i[i][4] > Epsilon){n2 = n2 - n0i[i][4] * th0i[i][4] / Tanh(th0i[i][4] / T0)}; n1 = n1 - n0i[i][4] * Math.log(Sinh(th0i[i][4] / T0));
      if (th0i[i][5] > Epsilon){n2 = n2 + n0i[i][5] * th0i[i][5] * Tanh(th0i[i][5] / T0)}; n1 = n1 + n0i[i][5] * Math.log(Cosh(th0i[i][5] / T0));
      if (th0i[i][6] > Epsilon){n2 = n2 - n0i[i][6] * th0i[i][6] / Tanh(th0i[i][6] / T0)}; n1 = n1 - n0i[i][6] * Math.log(Sinh(th0i[i][6] / T0));
      if (th0i[i][7] > Epsilon){n2 = n2 + n0i[i][7] * th0i[i][7] * Tanh(th0i[i][7] / T0)}; n1 = n1 + n0i[i][7] * Math.log(Cosh(th0i[i][7] / T0));
      n0i[i][3] = n0i[i][3] - 1;
      n0i[i][1] = n1 - n2 / T0 + n0i[i][3] * (1 + Math.log(T0));
      n0i[i][2] = n2 - n0i[i][3] * T0;
      for (j = 1 ; j <= 7; j++){n0i[i][j] = Rsr * n0i[i][j]};
      n0i[i][2] = n0i[i][2] - T0;
      n0i[i][1] = n0i[i][1] - Math.log(d0);
    }
}
class FlowStream {
  constructor() {
    this.x = Array(22).fill(0); //mol
    this.VolumetricFlow = 0; //m3/hr
    this.Pressure=100; //KPa
    this.Temperature=273.15; //Kelvin
    this.MolarMass=0; //g/mol
    this.Density=0.04464; //mol/l
    this.CompressibilityFactor=0;
    this.dPdD=0; // kPa/(mol-l)
    this.d2PdD2=0;
    this.d2PdTD=0;
    this.dPdT=0; // kPa/K
    this.U=0; //J/mol
    this.H=0; //J/mol
    this.S=0; //J/mol
    this.Cv=0; // J/(mol-K)
    this.Cp=0; // J/(mol-K)
    this.SpeedOfSound=0; //m/sec
    this.G=0; //J/mol
    this.JouleThomson=0; //K/kPa
    this.IsentropicExponent=0;
    this.A=0; //J/mol
    this.ierr=0;
    this.herr='';
  }
  MolarMassGERG(){
    //Sub MolarMassGERG(x)
    //Calculate molar mass of the mixture with the compositions contained in the x() input array
    //
    //Inputs;
    //   x() - Composition (mole fraction)
    //         Do not send mole percents or mass fractions in the x() array, otherwise the output will be incorrect.
    //         The sum of the compositions in the x() array must be equal to one.
    //         The order of the fluids in this array is given at the top of this code.
    //
    //Outputs;
    //    Mm - Molar mass (g/mol)
    this.MolarMass = 0;
    for (let i = 1; i <= NcGERG; i++){this.MolarMass = this.MolarMass + this.x[i] * MMiGERG[i]}
  }
  PressureGERG(){
    //Sub PressureGERG(T, D, x, P, Z)
    //Calculate pressure as a function of temperature and density.  The derivative d(P)/d(D) is also calculated
    //for use in the iterative DensityGERG subroutine (and is only returned as a common variable).
    //
    //Inputs;
    //     T - Temperature (K)
    //     D - Density (mol/l)
    //   x() - Composition (mole fraction)
    //         Do not send mole percents or mass fractions in the x() array, otherwise the output will be incorrect.
    //         The sum of the compositions in the x() array must be equal to one.
    //Outputs;
    //     P - Pressure (kPa)
    //     Z - Compressibility factor
    // dPdDsave - d(P)/d(D) [kPa/(mol/l)] (at constant temperature)
    //          - This variable is cached in the common variables for use in the iterative density solver, but not returned as an argument.
    let ar = this.AlpharGERG(0);
    this.CompressibilityFactor = 1 + ar[0][1];
    this.Pressure = this.Density * RGERG * this.Temperature * this.CompressibilityFactor;
    dPdDsave = RGERG * this.Temperature * (1 + 2 * ar[0][1] + ar[0][2]);
  }
  CalculateDensity(iFlag){
    //Sub DensityGERG(iFlag, T, P, x, D, ierr, herr)
    //Calculate density as a function of temperature and pressure.  This is an iterative routine that calls PressureGERG
    //to find the correct state point.  Generally only 6 iterations at most are required.
    //If the iteration fails to converge, the ideal gas density and an error message are returned.
    //No checks are made to determine the phase boundary, which would have guaranteed that the output is in the gas phase (or liquid phase when iFlag=2).
    //It is up to the user to locate the phase boundary, and thus identify the phase of the T and P inputs.
    //If the state point is 2-phase, the output density will represent a metastable state.
    //Inputs;
    // iFlag - Set to 0 for strict pressure solver in the gas phase without checks (fastest mode, but output state may not be stable single phase)
    //         Set to 1 to make checks for possible 2-phase states (result may still not be stable single phase, but many unstable states will be identified)
    //         Set to 2 to search for liquid phase (and make the same checks when iFlag=1)
    //     T - Temperature (K)
    //     P - Pressure (kPa)
    //   x() - Composition (mole fraction)
    //(An initial guess for the density can be sent in D as the negative of the guess for roots that are in the liquid phase instead of using iFlag=2)
    //Outputs;
    //     D - Density (mol/l)
    //  ierr - Error number (0 indicates no error)
    this.ierr = 0;
    //  herr - Error message if ierr is not equal to zero
    let nFail = 0;
    let iFail = 0;
    let plog;
    let vlog;
    let P2;
    let dpdlv;
    let vdiff;
    let tolr = 0.0000001; //tolr = 0.0000001
    let vinc;
    let Tcx;
    let Dcx;
    let PP;
    let it=1;
    if(this.Pressure < Epsilon) {this.Density=0;return}
    [Tcx, Dcx]=this.PseudoCriticalPointGERG();
    if (this.Density > -Epsilon){
      this.Density = this.Pressure / RGERG / this.Temperature;        //Ideal gas estimate for vapor phase
      if(iFlag == 2){this.Density=Dcx*3};  //Initial estimate for liquid phase
    }else{
      this.Density = Math.abs(this.Density);          //If D<0, then use as initial estimate
    }
    plog = Math.log(this.Pressure);
    vlog = -Math.log(this.Density);
    for(it = 1; it <= 50; it++){
      if (vlog < -7 || vlog > 100 || it == 20 || it == 30 || it == 40 || iFail == 1){
        //Current state is bad or iteration is taking too long.  Restart with completely different initial state
        iFail = 0;
        if(nFail > 2){
          it = 51;
          this.Density= this.Pressure / RGERG / this.Temperature;
          this.ierr=1;
          this.herr='Calculation failed to converge in GERG method, ideal gas density returned.';            
          return;
        }
        nFail = nFail + 1;
        if (nFail == 1){
          this.Density = Dcx * 3;    //If vapor phase search fails, look for root in liquid region
        }else if(nFail == 2){
          this.Density = Dcx * 2.5;  //If liquid phase search fails, look for root between liquid and critical regions
        }else if(nFail == 3){
          this.Density = Dcx * 2;    //If search fails, look for root in critical region
        }
        vlog = -Math.log(this.Density)
      }
      this.Density = Math.exp(-vlog);
      this.PressureGERG();
      P2=this.Pressure;
      this.CompressibilityFactor;
      //PressureGERG(T, D, x, P2, Z)
      if (dPdDsave < Epsilon || P2 < Epsilon){
        //Current state is 2-phase, try locating a different state that is single phase
        vinc = 0.1;
        if(this.Density > Dcx){vinc = -0.1};
        if(it > 5){vinc = vinc * 0.5};
        if(it > 10 && it < 20){vinc = vinc * 0.2};
        vlog = vlog + vinc;
      }else{
        //Find the next density with a first order Newton's type iterative scheme, with
        //log(P) as the known variable and log(v) as the unknown property.
        //See AGA 8 publication for further information.
        dpdlv = -this.Density * dPdDsave;     //d(p)/d[log(v)]
        vdiff = (Math.log(P2) - plog) * P2 / dpdlv;
        vlog = vlog - vdiff;
        if(Math.abs(vdiff)<tolr){
          //Check to see if state is possibly 2-phase, and if so restart
          if(dPdDsave < 0){
            iFail = 1;
          }else{
            this.Density = Math.exp(-vlog);
            //If requested, check to see if point is possibly 2-phase
            if (iFlag > 0) {
              this.CalculateProperties();
              //PropertiesGERG(T, D, x, PP, Z, dPdD, d2PdD2, d2PdTD, dPdT, U, H, S, Cv, Cp, W, G, JT, Kappa);
              if(PP <= 0 || this.dPdD <= 0 || this.d2PdTD <= 0){
                it = 51;
                this.Density=this.Pressure/RGERG/this.Temperature;
                this.ierr=1;
                this.herr='Calculation failed to converge in GERG method, ideal gas density returned.';            
                return;
              };
              if(this.Cv <= 0 || this.Cp <= 0 || this.SpeedOfSound <= 0){
                it = 51;
                this.Density=this.Pressure/RGERG/this.Temperature;
                this.ierr=1;
                this.herr='Calculation failed to converge in GERG method, ideal gas density returned.';            
                return;
              };
              it = 51;
              return;
            }
          }
        }
      }
    }
  }
  CalculateProperties(){
    //Sub PropertiesGERG(T, D, x, P, Z, dPdD, d2PdD2, d2PdTD, dPdT, U, H, S, Cv, Cp, W, G, JT, Kappa, Optional A)
    //Calculate thermodynamic properties as a function of temperature and density.
    //If the density is not known, call subroutine DensityGERG first with the known values of pressure and temperature.
    //Many of the formulas below do not appear in Part 2 of AGA 8, but rather in Part 1, which uses a dimensional Helmholtz equation with more direct formulas for quick calculation.
    //Inputs;
    //     T - Temperature (K)
    //     D - Density (mol/l)
    //   x() - Composition (mole fraction)
    //Outputs;
    //     P - Pressure (kPa)
    //     Z - Compressibility factor
    //  dPdD - First derivative of pressure with respect to density at constant temperature [kPa/(mol/l)]
    //d2PdD2 - Second derivative of pressure with respect to density at constant temperature [kPa/(mol/l)^2]
    //d2PdTD - Second derivative of pressure with respect to temperature and density [kPa/(mol/l)/K]
    //  dPdT - First derivative of pressure with respect to temperature at constant density (kPa/K)
    //     U - Internal energy (J/mol)
    //     H - Enthalpy (J/mol)
    //     S - Entropy [J/(mol-K)]
    //    Cv - Isochoric heat capacity [J/(mol-K)]
    //    Cp - Isobaric heat capacity [J/(mol-K)]
    //     W - Speed of sound (m/s)
    //     G - Gibbs energy (J/mol)
    //    JT - Joule-Thomson coefficient (K/kPa)
    // Kappa - Isentropic Exponent
    //     A - Helmholtz energy (J/mol)
    //Calculate molar mass
    this.MolarMassGERG();
    //Calculate the ideal gas Helmholtz energy, and its first and second derivatives with respect to temperature.
    let a0=this.Alpha0GERG();
    //Calculate the real gas Helmholtz energy, and its derivatives with respect to temperature and/or density.
    let ar=this.AlpharGERG(1);
    let RT = RGERG * this.Temperature;
    this.CompressibilityFactor = 1 + ar[0][1];
    this.Pressure = this.Density * RT * this.CompressibilityFactor;
    this.dPdD = RT * (1 + 2 * ar[0][1] + ar[0][2]);
    this.dPdT = this.Density * RGERG * (1 + ar[0][1] - ar[1][1]);
    this.d2PdTD = RGERG * (1 + 2 * ar[0][1] + ar[0][2] - 2 * ar[1][1] - ar[1][2]);
    this.A = RT * (a0[0] + ar[0][0]);
    this.G = RT * (1 + ar[0][1] + a0[0] + ar[0][0]);
    this.U = RT * (a0[1] + ar[1][0]);
    this.H = RT * (1 + ar[0][1] + a0[1] + ar[1][0]);
    this.S = RGERG * (a0[1] + ar[1][0] - a0[0] - ar[0][0]);
    this.Cv = -RGERG * (a0[2] + ar[2][0]);
    if(this.Density > Epsilon){
      this.Cp = this.Cv + this.Temperature * Math.pow((this.dPdT / this.Density),2) / this.dPdD;
      this.d2PdD2 = RT * (2 * ar[0][1] + 4 * ar[0][2] + ar[0][3]) / this.Density;
      this.JouleThomson = (this.Temperature / this.Density * this.dPdT / this.dPdD - 1) / this.Cp / this.Density; //=(dB/dT*T-B)/Cp for an ideal gas, but dB/dT is not known
    }else{
      this.Cp = this.Cv + RGERG;
      this.d2PdD2 = 0;
      this.JouleThomson = 1E+20;
    }
    this.SpeedOfSound = 1000 * this.Cp / this.Cv * this.dPdD / this.MolarMass;
    if (this.SpeedOfSound < 0){this.SpeedOfSound = 0};
    this.IsentropicExponent = this.SpeedOfSound * this.MolarMass / (RT * 1000 * this.CompressibilityFactor);
    this.SpeedOfSound = Math.sqrt(this.SpeedOfSound);
  }
  //The following routines are low-level routines that should not be called outside of this code.
  ReducingParametersGERG(Tr, Dr){
    //Private Sub ReducingParametersGERG(x, Tr, Dr)
    //Calculate reducing variables.  Only need to call this if the composition has changed.
    //
    //Inputs;
    //   x() - Composition (mole fraction)
    //
    //Outputs;
    //    Tr - Reducing temperature (K)
    //    Dr - Reducing density (mol/l)
    let Vr;
    let xij;
    let F;
    let i;
    let j;
    let icheck = 0;
    //Check to see if a component fraction has changed.  If x is the same as the previous call, then exit.
    for (i = 1; i <= NcGERG; i++){
      if (Math.abs(this.x[i] - xold[i]) > 0.0000001){icheck = 1}
      xold[i] = this.x[i];
    }
    if (icheck == 0){
      Dr = Drold;
      Tr = Trold;
      return [Tr, Dr];
    }
    Told = 0;
    Trold2 = 0;
    //Calculate reducing variables for T and D
    Dr = 0;
    Vr = 0;
    Tr = 0;
    for (i = 1; i <= NcGERG; i++){
      if (this.x[i] > Epsilon){
        F = 1;
        for (j = i; j <= NcGERG; j++){
          if (this.x[j] > Epsilon){
            xij = F * (this.x[i] * this.x[j]) * (this.x[i] + this.x[j]);
            Vr = Vr + xij * gvij[i][j] / (bvij[i][j] * this.x[i] + this.x[j]);
            Tr = Tr + xij * gtij[i][j] / (btij[i][j] * this.x[i] + this.x[j]);
            F = 2;
          }
        }
      }
    }
    if (Vr > Epsilon){Dr = 1 / Vr}
    Drold = Dr;
    Trold = Tr;
    return [Tr,Dr];
  }
  Alpha0GERG(){
    //Private Sub Alpha0GERG(T, D, x, a0)
    //Calculate the ideal gas Helmholtz energy and its derivatives with respect to tau and delta.
    //This routine is not needed when only P (or Z) is calculated.
    //Inputs;
    //     T - Temperature (K)
    //     D - Density (mol/l)
    //   x() - Composition (mole fraction)
    //Outputs;
    // a0(0) - Ideal gas Helmholtz energy (dimensionless [i.e., divided by RT])
    // a0(1) - tau*partial(a0)/partial(tau)
    // a0(2) - tau^2*partial^2(a0)/partial(tau)^2
    let a0 = Array(3).fill(0);
    let LogT;
    let LogD;
    let LogHyp;
    let th0T;
    let LogxD;
    let SumHyp0;
    let SumHyp1;
    let SumHyp2;
    let em;
    let ep;
    let hcn;
    let hsn;
    if (this.Density > Epsilon){LogD = Math.log(this.Density)}else{LogD = Math.log(Epsilon)}
    LogT = Math.log(this.Temperature);
    for (let i = 1; i <= NcGERG; i++){
      if (this.x[i] > Epsilon){
        LogxD = LogD + Math.log(this.x[i]);
        SumHyp0 = 0;
        SumHyp1 = 0;
        SumHyp2 = 0;
        for (let j = 4; j <= 7; j++){
          if (th0i[i][j] > Epsilon){
            th0T = th0i[i][j] / this.Temperature;
            ep = Math.exp(th0T);
            em = 1 / ep;
            hsn = (ep - em)*0.5;
            hcn = (ep + em)*0.5;
            if(j == 4 || j == 6){
              LogHyp = Math.log(Math.abs(hsn))
              SumHyp0 = SumHyp0 + n0i[i][j] * LogHyp;
              SumHyp1 = SumHyp1 + n0i[i][j] * th0T * hcn / hsn;
              SumHyp2 = SumHyp2 + n0i[i][j] * Math.pow((th0T / hsn), 2);
            }else{
              LogHyp = Math.log(Math.abs(hcn));
              SumHyp0 = SumHyp0 - n0i[i][j] * LogHyp;
              SumHyp1 = SumHyp1 - n0i[i][j] * th0T * hsn / hcn;
              SumHyp2 = SumHyp2 + n0i[i][j] * Math.pow((th0T / hcn), 2);
            }
          }
        }
        a0[0] = a0[0] + this.x[i] * (LogxD + n0i[i][1] + n0i[i][2] / this.Temperature - n0i[i][3] * LogT + SumHyp0);
        a0[1] = a0[1] + this.x[i] * (n0i[i][3] + n0i[i][2] / this.Temperature + SumHyp1);
        a0[2] = a0[2] - this.x[i] * (n0i[i][3] + SumHyp2);
      }
    }
    return a0;
  }
  AlpharGERG(itau){
    //Private Sub AlpharGERG(itau, idel, T, D, x, ar)
    //Calculate dimensionless residual Helmholtz energy and its derivatives with respect to tau and delta.
    //Inputs;
    //  itau - Set this to 1 to calculate "ar" derivatives with respect to tau [i.e., ar(1,0), ar(1,1), and ar(2,0)], otherwise set it to 0.
    //  idel - Currently not used, but kept as an input for future use in specifing the highest density derivative needed.
    //     T - Temperature (K)
    //     D - Density (mol/l)
    //   x() - Composition (mole fraction)
    //Outputs;
    // ar(0,0) - Residual Helmholtz energy (dimensionless, =a/RT)
    // ar(0,1) -     delta*partial  (ar)/partial(delta)
    // ar(0,2) -   delta^2*partial^2(ar)/partial(delta)^2
    // ar(0,3) -   delta^3*partial^3(ar)/partial(delta)^3
    // ar(1,0) -       tau*partial  (ar)/partial(tau)
    // ar(1,1) - tau*delta*partial^2(ar)/partial(tau)/partial(delta)
    // ar(2,0) -     tau^2*partial^2(ar)/partial(tau)^2
    let mn;
    let Tr;
    let Dr;
    let del;
    let tau;
    let lntau;
    let ex;
    let ex2;
    let ex3;
    let cij0;
    let eij0;
    let delp=Array(7).fill(0);
    let Expd=Array(7).fill(0);
    let ndt;
    let ndtd;
    let ndtt;
    let xijf;
    let ar=zeros2(3,4);
    //Set up del, tau, log(tau), and the first 7 calculations for del^i
    [Tr, Dr]=this.ReducingParametersGERG(Tr, Dr);
    del = this.Density / Dr;
    tau = Tr / this.Temperature;
    lntau = Math.log(tau);
    delp[1] = del;
    Expd[1] = Math.exp(-delp[1]);
    for (let i = 2; i <= 7; i++){
      delp[i] = delp[i - 1] * del;
      Expd[i] = Math.exp(-delp[i]);
    }
    //If temperature has changed, calculate temperature dependent parts
    if (Math.abs(this.Temperature - Told) > 0.0000001 || Math.abs(Tr - Trold2) > 0.0000001){this.tTermsGERG(lntau)}
    Told = this.Temperature;
    Trold2 = Tr;
    //Calculate pure fluid contributions
    for (let i = 1; i <= NcGERG; i++){
      if (this.x[i] > Epsilon){
        for(let k = 1; k <= kpol[i]; k++){
          ndt = this.x[i] * delp[doik[i][k]] * taup[i][k];
          ndtd = ndt * doik[i][k];
          ar[0][1] = ar[0][1] + ndtd;
          ar[0][2] = ar[0][2] + ndtd * (doik[i][k] - 1);
          if(itau > 0){
            ndtt = ndt * toik[i][k];
            ar[0][0] = ar[0][0] + ndt;
            ar[1][0] = ar[1][0] + ndtt;
            ar[2][0] = ar[2][0] + ndtt * (toik[i][k] - 1);
            ar[1][1] = ar[1][1] + ndtt * doik[i][k];
            ar[1][2] = ar[1][2] + ndtt * doik[i][k] * (doik[i][k] - 1);
            ar[0][3] = ar[0][3] + ndtd * (doik[i][k] - 1) * (doik[i][k] - 2);
          }
        }
        for(let k = 1 + kpol[i]; k <= kpol[i] + kexp[i]; k++){
          ndt = this.x[i] * delp[doik[i][k]] * taup[i][k] * Expd[coik[i][k]];
          ex = coik[i][k] * delp[coik[i][k]];
          ex2 = doik[i][k] - ex;
          ex3 = ex2 * (ex2 - 1);
          ar[0][1] = ar[0][1] + ndt * ex2;
          ar[0][2] = ar[0][2] + ndt * (ex3 - coik[i][k] * ex);
          if(itau > 0){
            ndtt = ndt * toik[i][k];
            ar[0][0] = ar[0][0] + ndt;
            ar[1][0] = ar[1][0] + ndtt;
            ar[2][0] = ar[2][0] + ndtt * (toik[i][k] - 1);
            ar[1][1] = ar[1][1] + ndtt * ex2;
            ar[1][2] = ar[1][2] + ndtt * (ex3 - coik[i][k] * ex);
            ar[0][3] = ar[0][3] + ndt * (ex3 * (ex2 - 2) - ex * (3 * ex2 - 3 + coik[i][k]) * coik[i][k]);
          }
        }
      }
    }
    //Calculate mixture contributions
    for (let i = 1; i <= NcGERG - 1; i++){
      if (this.x[i] > Epsilon){
        for (let j = i + 1; j <= NcGERG; j++){
          if (this.x[j] > Epsilon){
            mn = mNumb[i][j];
            if (mn >= 0){
              xijf = this.x[i] * this.x[j] * fij[i][j];
              for (let k = 1; k <= kpolij[mn]; k++){
                ndt = xijf * delp[dijk[mn][k]] * taupijk[mn][k];
                ndtd = ndt * dijk[mn][k];
                ar[0][1] = ar[0][1] + ndtd;
                ar[0][2] = ar[0][2] + ndtd * (dijk[mn][k] - 1);
                if (itau > 0){
                  ndtt = ndt * tijk[mn][k];
                  ar[0][0] = ar[0][0] + ndt;
                  ar[1][0] = ar[1][0] + ndtt;
                  ar[2][0] = ar[2][0] + ndtt * (tijk[mn][k] - 1);
                  ar[1][1] = ar[1][1] + ndtt * dijk[mn][k];
                  ar[1][2] = ar[1][2] + ndtt * dijk[mn][k] * (dijk[mn][k] - 1);
                  ar[0][3] = ar[0][3] + ndtd * (dijk[mn][k] - 1) * (dijk[mn][k] - 2);
                }
              }
              for (let k = 1 + kpolij[mn]; k <= kpolij[mn] + kexpij[mn]; k++){
                cij0 = cijk[mn][k] * delp[2];
                eij0 = eijk[mn][k] * del;
                ndt = xijf * nijk[mn][k] * delp[dijk[mn][k]] * Math.exp(cij0 + eij0 + gijk[mn][k] + tijk[mn][k] * lntau);
                ex = dijk[mn][k] + 2 * cij0 + eij0;
                ex2 = (ex * ex - dijk[mn][k] + 2 * cij0);
                ar[0][1] = ar[0][1] + ndt * ex;
                ar[0][2] = ar[0][2] + ndt * ex2;
                if(itau > 0){
                  ndtt = ndt * tijk[mn][k];
                  ar[0][0] = ar[0][0] + ndt;
                  ar[1][0] = ar[1][0] + ndtt;
                  ar[2][0] = ar[2][0] + ndtt * (tijk[mn][k] - 1);
                  ar[1][1] = ar[1][1] + ndtt * ex;
                  ar[1][2] = ar[1][2] + ndtt * ex2;
                  ar[0][3] = ar[0][3] + ndt * (ex * (ex2 - 2 * (dijk[mn][k] - 2 * cij0)) + 2 * dijk[mn][k]);
                }
              }
            }
          }
        }
      }
    }
    return ar;
  }
  tTermsGERG(lntau){
    //Private Sub tTermsGERG(lntau, x)
    //Calculate temperature dependent parts of the GERG-2008 equation of state
    let i = 5; //Use propane to get exponents for short form of EOS
    let j;
    let k;
    let mn;
    let taup0=Array(12).fill(0);
    for (k = 1 ; k <= kpol[i] + kexp[i]; k++){
      taup0[k] = Math.exp(toik[i][k] * lntau);
    }
    for (i = 1 ; i <= NcGERG; i ++){
      if (this.x[i] > Epsilon){
        if (i > 4 && i != 15 && i != 18 && i != 20){
          for (k = 1; k <= kpol[i] + kexp[i]; k++){
            taup[i][k] = noik[i][k] * taup0[k];
          }
        }else{
          for (k = 1 ; k <= kpol[i] + kexp[i]; k++){
            taup[i][k] = noik[i][k] * Math.exp(toik[i][k] * lntau);
          }
        }
      }
    }
    for (i = 1 ; i <= NcGERG - 1; i++){
      if (this.x[i] > Epsilon){
        for (j = i + 1 ; j <= NcGERG; j++){
          if (this.x[j] > Epsilon){
            mn = mNumb[i][j];
            if (mn >= 0){
              for (k = 1 ; k <= kpolij[mn]; k++){
                taupijk[mn][k] = nijk[mn][k] * Math.exp(tijk[mn][k] * lntau);
              }
            }
          }
        }
      }
    }
    return;
  }
  PseudoCriticalPointGERG(){
    //Sub PseudoCriticalPointGERG(x, Tcx, Dcx)
    //Calculate a pseudo critical point as the mole fraction average of the critical temperatures and critical volumes
    let Vcx=0;
    let Tcx = 0;
    let Dcx = 0;
    for (let i = 1; i <= NcGERG; i++){
      Tcx = Tcx + this.x[i] * Tc[i];
      Vcx = Vcx + this.x[i] / Dc[i];
    }
    if(Vcx > Epsilon){Dcx = 1 / Vcx}
    return [Tcx, Dcx];
  }
}