Non-Restart Unsteady Time, TimeIter, and IC Outputs Not Correct?

[j-signorelli]

There seems to potentially be a bug with doing an unsteady dual-timestepping simulation without a provided initial condition (restart file):

When no restart file is provided, the first inner iterations have Time_Iter=0 and Cur_Time=0 (the state before these inner iterations). After completion of this time iteration, a file flow_00000.vtu and all others are outputted. These files are not the initial condition as specified by the configuration file -- they seem to actually be the solution after the first time step. This can be reproduced easily in the config file I have attached to this issue (an updated version of TestCases/plunging_naca0012 for SU2 v8). The flow_00000.vtu file has non-uniform flowfields, which doesn't make sense.

For simulations where a restart file like restart_00000.dat is provided, the Time_Iter=1 and Cur_Time=dt (the state after these inner iterations), and the subsequently outputted files have the correct time iteration appended to it.

I think that for non-restart unsteady simulations, the IC should be outputted as solely just the initialization before any inner iterations are completed, Time_Iter++ and Cur_Time+=dt, and THEN inner iterations performed.

plunging_NACA0012.cfg.txt

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Desktop (please complete the following information):

• OS: Linux (Ubuntu 22.04)
• C++ compiler and version: GNU
• MPI implementation and version: MPICH
• SU2 Version: v8.0.1