Undo a modification in the documentation

doc/source/examples/incompressible-flow/2d-naca0012-low-reynolds/2d-naca0012-low-reynolds.rst

@@ -28,7 +28,7 @@ All files mentioned below are located in the example's folder (``examples/incomp
 Description of the Case
 -----------------------
 
-In this example, a two-dimensional flow around a NACA airfoil is studied. According to Wikipedia, the *NACA airfoils are airfoil shapes for aircraft wings developed by the National Advisory Committee for Aeronautics (NACA)*. The NACA is the ancestor of the well-known `NASA <https://www.nasa.gov/about/index.html>`_. The airfoils, simply referred to as NACAs afterwards, can be described by a set of four parameters for the simpler airfoils, allowing the generation of a lot of different profiles. Since we deal with a symmetrical NACA we will only consider two of these four parameters, which describe the maximum thickness of the airfoil in percentage of the chord. The maximum camber and its position, are set to zero. The problem under study is presented in the figure below, which details the boundary conditions chosen and gives an idea of the size of the computational domain.
+In this example, a two-dimensional flow around a NACA airfoil is studied. According to Wikipedia, the *NACA airfoils are airfoil shapes for aircraft wings developed by the National Advisory Committee for Aeronautics (NACA)*. The NACA is the ancestor of the well-known NASA <https://www.nasa.gov/about/index.html>_. The airfoils, simply referred to as NACAs afterwards, can be described by a set of four digits for the simpler airfoils, allowing the generation of a lot of different profiles. Since we deal with a symmetrical NACA we will only consider the last two digits, which describe the maximum thickness of the airfoil in percentage of the chord. The first two digits, describing the maximum camber and its position, are set to zero. The problem under study is presented in the figure below, which details the boundary conditions chosen and gives an idea of the size of the computational domain.
 
 .. image:: image/explanations_BC.png