adapted heatpipe to book, changed to pnsw

lecture/mm/heatpipe/heatpipe.input

 [TimeLoop]
 DtInitial = 1 # [s]
-TEnd = 2.2e12 # [s]
-EpisodeLength = 1.e11
+TEnd = 2.2e10 # [s]
+EpisodeLength = 1.e8
 
 [Grid]
 File = ./grids/heatpipe.dgf

lecture/mm/heatpipe/heatpipeproblem.hh

@@ -55,6 +55,10 @@ struct Problem<TypeTag, TTag::HeatPipeTypeTag> { using type = HeatPipeProblem<Ty
 template<class TypeTag>
 struct FluidSystem<TypeTag, TTag::HeatPipeTypeTag> { using type = FluidSystems::H2OAir<GetPropType<TypeTag, Properties::Scalar>>; };
 
+// pn-sw formulation
+template<class TypeTag>
+struct Formulation<TypeTag, TTag::HeatPipeTypeTag> { static constexpr auto value = TwoPFormulation::p1s0; };
+
 // Set the spatial parameters
 template<class TypeTag>
 struct SpatialParams<TypeTag, TTag::HeatPipeTypeTag>
@@ -117,7 +121,7 @@ public:
         // we could use another phase presence (onlyWater) on the left, here simplified for better
         // convergence behavior
         values[Indices::pressureIdx] = 1.013e5;
-        values[Indices::switchIdx] = 0.01;
+        values[Indices::switchIdx] = 0.99;
         values[Indices::temperatureIdx] = 341.75;
         values.setState(Indices::bothPhases);