[Mechanics] Changed the way to read reference_temperature

ProcessLib/HydroMechanics/CreateHydroMechanicsProcess.cpp

@@ -183,7 +183,8 @@ std::unique_ptr<Process> createHydroMechanicsProcess(
     // Reference temperature
     const auto& reference_temperature =
         //! \ogs_file_param{prj__processes__process__HYDRO_MECHANICS__reference_temperature}
-        config.getConfigParameterOptional<double>("reference_temperature");
+        config.getConfigParameter<double>(
+            "reference_temperature", std::numeric_limits<double>::quiet_NaN());
 
     HydroMechanicsProcessData<DisplacementDim> process_data{
         std::move(material),
@@ -195,7 +196,7 @@ std::unique_ptr<Process> createHydroMechanicsProcess(
         porosity,
         solid_density,
         specific_body_force,
-        *reference_temperature};
+        reference_temperature};
 
     SecondaryVariableCollection secondary_variables;
 

ProcessLib/LIE/HydroMechanics/CreateHydroMechanicsProcess.cpp

@@ -305,7 +305,8 @@ std::unique_ptr<Process> createHydroMechanicsProcess(
     // Reference temperature
     const auto& reference_temperature =
         //! \ogs_file_param{prj__processes__process__HYDRO_MECHANICS_WITH_LIE__reference_temperature}
-        config.getConfigParameterOptional<double>("reference_temperature");
+        config.getConfigParameter<double>(
+            "reference_temperature", std::numeric_limits<double>::quiet_NaN());
 
     HydroMechanicsProcessData<GlobalDim> process_data{
         std::move(material),
@@ -322,7 +323,7 @@ std::unique_ptr<Process> createHydroMechanicsProcess(
         initial_effective_stress,
         initial_fracture_effective_stress,
         deactivate_matrix_in_flow,
-        *reference_temperature};
+        reference_temperature};
 
     SecondaryVariableCollection secondary_variables;
 

ProcessLib/LIE/SmallDeformation/CreateSmallDeformationProcess.cpp

@@ -170,11 +170,12 @@ std::unique_ptr<Process> createSmallDeformationProcess(
     // Reference temperature
     const auto& reference_temperature =
         //! \ogs_file_param{prj__processes__process__SMALL_DEFORMATION_WITH_LIE__reference_temperature}
-        config.getConfigParameterOptional<double>("reference_temperature");
+        config.getConfigParameter<double>(
+            "reference_temperature", std::numeric_limits<double>::quiet_NaN());
 
     SmallDeformationProcessData<DisplacementDim> process_data(
         std::move(material), std::move(fracture_model),
-        std::move(vec_fracture_property), *reference_temperature);
+        std::move(vec_fracture_property), reference_temperature);
 
     SecondaryVariableCollection secondary_variables;
 

ProcessLib/SmallDeformation/CreateSmallDeformationProcess.cpp

@@ -96,11 +96,12 @@ createSmallDeformationProcess(
     // Reference temperature
     const auto& reference_temperature =
         //! \ogs_file_param{prj__processes__process__SMALL_DEFORMATION__reference_temperature}
-        config.getConfigParameterOptional<double>("reference_temperature");
+        config.getConfigParameter<double>(
+            "reference_temperature", std::numeric_limits<double>::quiet_NaN());
 
     SmallDeformationProcessData<DisplacementDim> process_data{
         std::move(material), solid_density, specific_body_force,
-        *reference_temperature};
+        reference_temperature};
 
     SecondaryVariableCollection secondary_variables;