Hydrodynamic Stability Implementation in FreeFEM

General Discussion
26

(i) Doubt-1: Paraview Visualization
At the end of the code: FreeFem-sources/navier-stokes-2d-PETSc.edp at develop · FreeFem/FreeFem-sources · GitHub, I added the following lines:

load “iovtk”
int[int] Order = [1]; //Order = [2];…Does NOT work in Paraview
string DataName = “uc”;
savevtk(“uc.vtu”, Th, uc1, uc2, pc, dataname=DataName, order=Order);

I checked that “Order = [2]” does not work for Paraview. Only load “int[int] Order = [1]” works for Paraview.

So, using “int[int] Order = [1]”, when I run the code on Win10 (V4.9) using FreeFem+±mpi.exe, the following files are written: uc.pvd and uc_0000.vtu. When the “uc_0000.vtu” is opened in Paraview, I am only getting x-component of velocity (i.e., uc1). I am not seeing the other variables: uc2 and pc. How to see all the variables (uc1, uc2 and pc) in paraview so that vector plot can be generated?

(ii) Doubt-2: The codes FreeFem-sources/navier-stokes-2d-PETSc.edp at develop · FreeFem/FreeFem-sources · GitHub and FreeFem-sources/navier-stokes-2d-SLEPc-complex.edp at develop · FreeFem/FreeFem-sources · GitHub can be run using “FreeFem+±mpi.exe” and “mpiexec.exe”. When running the above two codes using “mpiexec.exe”, the following black lines are coming as follows:

mpiexecExe_BaseFlow
mpiexecExe_BaseFlow1268×574 143 KB

mpiexecExe_LeadEigen
mpiexecExe_LeadEigen1245×573 151 KB

When running the code using “FreeFem+±mpi.exe”, the black lines are not present.

27

You need to write [uc1, uc2, pc], not uc1, uc2, pc. If you don’t need any lines, it means that there is no domain decomposition, i.e., you are running your code on a single process, double check by adding cout << mpisize << endl; in your script.

28

I am trying to run the code: FreeFem-sources/natural-convection-fieldsplit-2d-PETSc.edp at develop · FreeFem/FreeFem-sources · GitHub, but the following error is coming:
NC_Error