[ex][ffpm] set the boundary condtions for SST more clearly

exercises/exercise-coupling-ff-pm/README.md

@@ -382,11 +382,14 @@ freeflowProblem->updateDynamicWallProperties(freeflowSol);
 In addition to designating the locations of walls,
 additional boundary conditions and initial conditions need to be set for the two new primary variables $k$ and $\omega$.
 In the `boundaryTypes` function, set both variables on all walls to be dirichlet, except for the right boundary, which should have outflow conditions.
+
 For the initial conditions, Reynolds number specific base conditions should be applied everywhere.
 In the problem constructor, uncomment the code calculating these terms,
-then apply the `turbulentKineticEnergy_`and `dissipation_` variables to their primary variables in all locations,
-except for the wall boundaries, where these values can be set to zero.
-In addition, dirichlet constraints for the dissipation or $\omega$ variable will be set for all wall adjacent cells.
+then apply the `turbulentKineticEnergy_`and `dissipation_` variables to their primary variables in all locations.
+Within the dirichlet function for cell faces (`dirichlet(element, scvf)`),
+we also need to specify that these variables should be fixed to 0 at the wall.
+
+In addition, dirichlet cell constraints for the dissipation or $\omega$ variable will be set for all wall adjacent cells.
 This is done in the `isDirichletCell` function, as well as the `dirichlet` function already, and requires no further changes.
 
 Compile and run your new coupled problem and take a look at the results in Paraview.
@@ -405,7 +408,7 @@ you can use symmetric boundary conditions at the top boundary of your free flow
 values.setAllSymmetry();
 ```
 
-In addition, you have to remove the condition `onUpperBoundary_(globalPos)` from the `initialAtPos(globalPos)` method.
+In addition, you have to remove the condition `onUpperBoundary_(globalPos)` from the `initialAtPos(globalPos)` method and the `dirichlet(element, scvf)` method.
 
 __Task C__:
 

exercises/exercise-coupling-ff-pm/turbulence/freeflowsubproblem.hh

@@ -181,6 +181,18 @@ public:
     {
         const auto globalPos = scvf.ipGlobal();
         PrimaryVariables values(initialAtPos(globalPos));
+
+        // TODO: dumux-course-task 3.A
+        // Add dirichlet conditions setting TKE and Dissipation to zero on the upper and lower walls.
+        // TODO: dumux-course-task 3.B
+        // Remove the condition `onUpperBoundary_(globalPos)` here.
+        // if (onUpperBoundary_(globalPos) || onLowerBoundary_(globalPos))
+        // {
+        //     values[Indices::turbulentKineticEnergyIdx] = 0.0;
+        //     values[Indices::dissipationIdx] = 0.0;
+        // }
+    }
+
         return values;
     }
 

exercises/solution/exercise-coupling-ff-pm/turbulence/freeflowsubproblem.hh

@@ -216,6 +216,20 @@ public:
     {
         const auto globalPos = scvf.ipGlobal();
         PrimaryVariables values(initialAtPos(globalPos));
+
+#if EXNUMBER == 1
+        if (onUpperBoundary_(globalPos) || onLowerBoundary_(globalPos))
+        {
+            values[Indices::turbulentKineticEnergyIdx] = 0.0;
+            values[Indices::dissipationIdx] = 0.0;
+        }
+#elif EXNUMBER  >= 2
+        if (onLowerBoundary_(globalPos))
+        {
+            values[Indices::turbulentKineticEnergyIdx] = 0.0;
+            values[Indices::dissipationIdx] = 0.0;
+        }
+#endif
         return values;
     }
 
@@ -327,20 +341,6 @@ public:
         values[Indices::dissipationIdx] = dissipation_;
 #endif
 
-#if EXNUMBER == 1
-        if (onLowerBoundary_(globalPos) || onUpperBoundary_(globalPos))
-        {
-            values[Indices::turbulentKineticEnergyIdx] = 0.0;
-            values[Indices::dissipationIdx] = 0.0;
-        }
-#elif EXNUMBER >= 2
-        if (onLowerBoundary_(globalPos) || onUpperBoundary_(globalPos))
-        {
-            values[Indices::turbulentKineticEnergyIdx] = 0.0;
-            values[Indices::dissipationIdx] = 0.0;
-        }
-#endif
-
 #if EXNUMBER >= 2
         if(onLowerBoundary_(globalPos))
             values[Indices::velocityXIdx] = 0.0;