2D Couette Flow tutorial have a long simulation time

Just Starting
1

Hi guys!

I am new to PyFR and was trying to run the tutorial case called 2D Couette Flow. This works fine, the only problem is that the simulation is estimated to spend 80 hours. This should be a simple 2D simulation, and it should be done in less then 10minutes i assume. I use a very strong computer which is suitable for simulations. Any ideas on why the simulation time is this large?

Regards Stian

2

Hi Stian,

3

Hi Freddie, thanks for the quick repply!

Yes I am running on OpenMP. I followed the steps on PyFR.org, and pasted this into my .ini for the tutorial:

[backend-openmp]
cc = gcc
cblas = /usr/lib/x86_64-linux-gnu/blas/libblas.so.3
cblas-type = parallel

Im not a 100% sure about what you mean with a single thread?

Stian

mandag 17. februar 2020 13.16.25 UTC+1 skrev Freddie Witherden følgende:

4

Hi Stian
assuming you are running PyFR on Linux, before running it issue the command
export OMP_NUM_THREADS=1

this will set the number of openMP threads to one. Then in the same terminal window, call pyfr as you were doing before.

Best
Giorgio

5

Thank you so much for the quick repply! I will try it out!

man. 17. feb. 2020 kl. 15:39 skrev Giorgio Giangaspero <giorgio.giangaspero@gmail.com>: