Fix restart file writing for time convergence and 2nd order time stepping

SU2_CFD/include/output/COutput.hpp

@@ -80,6 +80,8 @@ class COutput {
   char char_histfile[200];  /*! \brief Temporary variable to store the history filename */
   ofstream histFile;        /*! \brief Output file stream for the history */
 
+  bool cauchyTimeConverged; /*! \brief: Flag indicating that solver is already converged. Needed for writing restart files. */
+
   /** \brief Enum to identify the screen output format. */
   enum class ScreenOutputFormat {
     INTEGER,         /*!< \brief Integer format. Example: 34 */
@@ -439,12 +441,6 @@ class COutput {
      */
   bool MonitorTimeConvergence(CConfig *config, unsigned long Iteration);
 
-  /*!
-   * \brief Get time convergence of the specified windowed-time-averaged ouput of the problem.
-   * Indicates, if the time loop is converged. COnvergence criterion: Windowed time average
-   * \return Boolean indicating whether the problem is converged.
-   */
-  bool GetTimeConvergence() const {return TimeConvergence;}
 
   /*!
    * \brief Print a list of all history output fields to screen.
@@ -468,6 +464,15 @@ class COutput {
   bool SetResult_Files(CGeometry *geometry, CConfig *config, CSolver** solver_container,
                        unsigned long iter, bool force_writing = false);
 
+  /*!
+   * \brief Get convergence time convergence of the specified windowed-time-averaged ouput of the problem.
+   *        Delays solver stop, if Cauchy time convergence criterion is fullfilled, but 2nd order
+   *        time marching is active, to ensure that enough restart files are written.
+   * \param[in] config - Definition of the particular problem.
+   * \return <TRUE> if Solver has converged and has run another iteration.
+   */
+  bool GetCauchyCorrectedTimeConvergence(const CConfig *config);
+
   /*!
    * \brief Allocates the appropriate file writer based on the chosen format and writes sorted data to file.
    * \param[in] config - Definition of the particular problem.
@@ -581,6 +586,7 @@ class COutput {
     volumeOutput_List.push_back(name);
   }
 
+
   /*!
    * \brief Set the value of a volume output field
    * \param[in] name - Name of the field.
@@ -796,4 +802,3 @@ class COutput {
   inline virtual void SetAdditionalScreenOutput(CConfig *config){}
 
 };
-

SU2_CFD/src/drivers/CMultizoneDriver.cpp

@@ -37,6 +37,7 @@ CMultizoneDriver::CMultizoneDriver(char* confFile, unsigned short val_nZone, SU2
   /*--- Initialize the counter for TimeIter ---*/
   TimeIter = 0;
 
+
   /*--- Initialize some useful booleans ---*/
   fsi = false; cht = false;
 
@@ -486,7 +487,7 @@ void CMultizoneDriver::Output(unsigned long TimeIter) {
   for (iZone = 0; iZone < nZone; iZone++){
     wrote_files = output_container[iZone]->SetResult_Files(geometry_container[iZone][INST_0][MESH_0],
                                                             config_container[iZone],
-                                                            solver_container[iZone][INST_0][MESH_0], TimeIter, StopCalc);
+                                                            solver_container[iZone][INST_0][MESH_0], TimeIter, StopCalc );
   }
 
   if (wrote_files){
@@ -679,6 +680,7 @@ bool CMultizoneDriver::Monitor(unsigned long TimeIter){
 
     /*--- Check whether the outer time integration has reached the final time ---*/
     TimeConvergence = GetTimeConvergence();
+
     FinalTimeReached     = CurTime >= MaxTime;
     MaxIterationsReached = TimeIter+1 >= nTimeIter;
 
@@ -698,5 +700,5 @@ bool CMultizoneDriver::Monitor(unsigned long TimeIter){
 }
 
 bool CMultizoneDriver::GetTimeConvergence() const{
-  return driver_output->GetTimeConvergence();
+    return output_container[ZONE_0]->GetCauchyCorrectedTimeConvergence(config_container[ZONE_0]);
 }

SU2_CFD/src/drivers/CSinglezoneDriver.cpp

@@ -39,7 +39,6 @@ CSinglezoneDriver::CSinglezoneDriver(char* confFile,
 
   /*--- Initialize the counter for TimeIter ---*/
   TimeIter = 0;
-
 }
 
 CSinglezoneDriver::~CSinglezoneDriver(void) {
@@ -272,6 +271,7 @@ bool CSinglezoneDriver::Monitor(unsigned long TimeIter){
     /*--- Check whether the outer time integration has reached the final time ---*/
 
     TimeConvergence = GetTimeConvergence();
+
     FinalTimeReached     = CurTime >= MaxTime;
     MaxIterationsReached = TimeIter+1 >= nTimeIter;
 
@@ -314,5 +314,5 @@ void CSinglezoneDriver::Runtime_Options(){
 }
 
 bool CSinglezoneDriver::GetTimeConvergence() const{
-  return output_container[ZONE_0]->GetTimeConvergence();
+  return output_container[ZONE_0]->GetCauchyCorrectedTimeConvergence(config_container[ZONE_0]);
 }

SU2_CFD/src/output/COutput.cpp

@@ -48,6 +48,7 @@
 
 COutput::COutput(CConfig *config, unsigned short nDim, bool fem_output): femOutput(fem_output) {
 
+  cauchyTimeConverged = false;
   this->nDim = nDim;
 
   rank = SU2_MPI::GetRank();
@@ -737,12 +738,22 @@ void COutput::WriteToFile(CConfig *config, CGeometry *geometry, unsigned short f
   }
 }
 
-
+bool COutput::GetCauchyCorrectedTimeConvergence(const CConfig *config){
+   if(!cauchyTimeConverged && TimeConvergence && config->GetTime_Marching() == TIME_MARCHING::DT_STEPPING_2ND){
+       // Change flags for 2nd order Time stepping: In case of convergence, this iter and next iter gets written out. then solver stops
+       cauchyTimeConverged = TimeConvergence;
+       TimeConvergence = false;
+    }
+    else if(cauchyTimeConverged){
+       TimeConvergence = cauchyTimeConverged;
+    }
+    return TimeConvergence;
+}
 
 bool COutput::SetResult_Files(CGeometry *geometry, CConfig *config, CSolver** solver_container,
                               unsigned long iter, bool force_writing){
 
-  bool writeFiles = WriteVolume_Output(config, iter, force_writing);
+  bool writeFiles = WriteVolume_Output(config, iter, force_writing || cauchyTimeConverged);
 
   /*--- Check if the data sorters are allocated, if not, allocate them. --- */