Documentation du code de simulation numérique SUNFLUIDH

This data setup allows the user to set the time parameters of the code in order to :

• perform the numerical simulation (time step, stopping criteria…)
• record the results associated to time series of probes, instantaneous quantity fields, statistical quantities.
• record the backup/restart files

• Type : Integer Value
• This data indicates how is initialized the simulation :
  • 0 : The simulation starts from the beginning corresponding to an initialization state.
  • 1 or 2 : The simulation is resumed from a temporary backup file recorded during the previous simulation. Useful to resume a simulation suddenly interrupted. As the temporary backup file a regularly removed during a simulation, only the two last files created by the code are available. They correspond to the number 1 or 2. The number of last file created is recorded in the file num_sav_xxxxx.d (xxxxx correspond to the MPI process number when the simulation is performed in a domain decomposition approach).
  • 3 : The simulation is resumed from the last backup file built during the last time step of the previous simulation. Useful to continue a incompleted simulation. The number 3 must be present in the file num_sav_xxxxx.d (proof that the previous simulation is correctly completed), otherwise the numbers 0, 1 or 2 (related to the previous cases) will be present.

• Type : Boolean value
• Activation of the stopping criterion for steady flow (based on the L2-norm of the time variation of quantities).

• Type : Real value
• When the L2-norm of the time variation of quantities is lower than this value, the simulation is stopped and the solution corresponds to a steady flow.

• Type : Integer value
• This value is the maximum of time iterations performed by the code before stopping.

• Type : Real value
• This value is the physical time limit reached by the simulation before stopping.

• Type : Integer value
• Selection of way to define the numerical time step :
  • 0 : The time step is constant and defined by the user by means of the variable “Timestep_max” (see further).
  • -1 : The time step evolves lineraly between the values given by “Timestep_min” and “Timestep_max”. The range of variation is defined by the variable “Iterations_For_Timestep_Linear_Progress” (in time iteration number).
  • 1 : The time step is calculated for each time iteration by means of the CFL parameter. The CFL parameter can be constant, it is thus defined by the variable “CFL_Max”.
    It can also evolve linearly between the values given by “CFL_Min” and “CFL_Max” and the variable “the varievolves linearly between the values “Timestep_min” and “Timestep_max”. The range of variation is defined by the variable “Iterations_For_Timestep_Linear_Progress” (in time iteration number).

====