Prepare for PR

CHANGELOG.md

@@ -3,6 +3,12 @@
 All notable changes to the Lethe project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/).
 
+## [Master] - 2024-07-16
+
+### Added
+
+- MINOR A post-processing feature for the tracer flow rate through boundaries is added. This allows to produce data useful for residence time distribution analyses. [#1197](https://github.com/chaos-polymtl/lethe/pull/1197)
+
 ## [Master] - 2024-07-14
 
 ### Added

applications_tests/lethe-fluid/tracer_flow_rate.output

@@ -0,0 +1,35 @@
+Running on 1 MPI rank(s)...
+   Number of active cells:       64
+   Number of degrees of freedom: 243
+   Volume of triangulation:      0.04
+   Number of tracer degrees of freedom: 81
+Tracer statistics : 
+	     Min : 0
+	     Max : 0.788675
+	 Average : 0.0625
+	 Std-Dev : 0.19432
+------------------
+Tracer flow rates
+------------------
+Tracer flow rate at the boundaries : 
+	 boundary 0 : 8.2
+	 boundary 1 : 0
+	 boundary 2 : 0
+	 boundary 3 : 0
+
+*****************************
+Steady iteration:        1/1
+*****************************
+Tracer statistics : 
+	     Min : 1
+	     Max : 1
+	 Average : 1
+	 Std-Dev : 3.37941e-09
+------------------
+Tracer flow rates
+------------------
+Tracer flow rate at the boundaries : 
+	 boundary 0 : 0.2
+	 boundary 1 : -0.200001
+	 boundary 2 : 9.02388e-10
+	 boundary 3 : 2.18592e-09

applications_tests/lethe-fluid/tracer_flow_rate.prm

@@ -0,0 +1,98 @@
+set dimension = 2
+
+subsection simulation control
+  set method           = steady
+  set output frequency = 1
+end
+
+subsection FEM
+  set velocity order = 1
+  set pressure order = 1
+  set tracer order   = 1
+end
+
+subsection physical properties
+  set number of fluids = 1
+  subsection fluid 0
+    set kinematic viscosity = 0.01
+    set tracer diffusivity  = 1
+  end
+end
+
+subsection multiphysics
+  set fluid dynamics = true
+  set tracer         = true
+end
+
+subsection mesh
+  set type               = dealii
+  set grid type          = subdivided_hyper_rectangle
+  set grid arguments     = 1,  1: -0.1, -0.1: 0.1, 0.1 : true
+  set initial refinement = 3
+end
+
+subsection boundary conditions
+  set number         = 4
+  set time dependent = true
+  subsection bc 0
+    set id   = 0
+    set type = function
+    subsection u
+      set Function expression = 1
+    end
+  end
+  subsection bc 1
+    set id   = 1
+    set type = outlet
+  end
+  subsection bc 2
+    set id   = 2
+    set type = noslip
+  end
+  subsection bc 3
+    set id   = 3
+    set type = noslip
+  end
+end
+
+subsection boundary conditions tracer
+  set number = 1
+  subsection bc 0
+    set id   = 0
+    set type = dirichlet
+    subsection dirichlet
+      set Function expression = 1
+    end
+  end
+end
+
+subsection post-processing
+  set verbosity                   = verbose
+  set calculate tracer statistics = true
+  set tracer statistics name      = tracer_statistics
+
+  set calculate tracer flow rate = true
+  set tracer flow rate name      = tracer_flow_rate_test
+end
+
+subsection non-linear solver
+  subsection fluid dynamics
+    set verbosity      = quiet
+    set tolerance      = 1e-4
+    set max iterations = 10
+  end
+  subsection tracer
+    set verbosity      = quiet
+    set tolerance      = 1e-7
+    set max iterations = 30
+  end
+end
+
+subsection linear solver
+  subsection fluid dynamics
+    set verbosity = quiet
+  end
+  subsection tracer
+    set verbosity = quiet
+  end
+end

doc/source/parameters/cfd/post_processing.rst

@@ -55,9 +55,11 @@ This subsection controls the post-processing other than the forces and torque on
     #---------------------------------------------------
     # Multiphysics post-processing
     #---------------------------------------------------
-    # Tracer statistics
+    # Tracer postprocessing
     set calculate tracer statistics      = false
     set tracer statistics name           = tracer_statistics
+    set calculate tracer flow rate       = false
+    set tracer flow rate name            = tracer_flow_rate
 
     # Thermal postprocessing
     set postprocessed fluid              = both