Search found 197 matches
- Wed Oct 12, 2022 4:11 pm
- Forum: code_saturne usage
- Topic: RSM SSG model + Least Squares + All vertexes does not work
- Replies: 11
- Views: 4123
RSM SSG model + Least Squares + All vertexes does not work
Hello. I found that there is a bug with RSM SSG (didn't test with EBRSM) on tetra mesh when Least Squares gradient reconstruction is selected with Full (All vertex adjacent) option and "Improved pressure interpolation" is on . Calculation just crashes at first iteration when turbulence var...
- Wed Oct 12, 2022 3:45 pm
- Forum: code_saturne usage
- Topic: Restart simulation with different mesh
- Replies: 2
- Views: 1989
Re: Restart simulation with different mesh
Yes, it's simple and works for most cases if there is no divergence due to mesh change (you can use Upwind scemes for all variable on first restart iterations to stabilize).
You can find mesh_input.csm file in previous run checkpoint directory you interpolate from.
You can find mesh_input.csm file in previous run checkpoint directory you interpolate from.
- Mon Aug 29, 2022 8:58 am
- Forum: code_saturne usage
- Topic: Velocity Solution Artefacts
- Replies: 10
- Views: 3544
Re: Velocity Solution Artefacts
Thanks for you description about CFL numbers. Maybe some extra options in GUI will be useful for cases with such problems.
- Fri Aug 26, 2022 7:53 am
- Forum: code_saturne usage
- Topic: Velocity Solution Artefacts
- Replies: 10
- Views: 3544
Re: Velocity Solution Artefacts
The problem disappeared after reducing target CFL number from 2.0 to 0.5...1.0 (real local CFL maximum < 2). So it was numerical scheme instability. But, in some cases, there may be instability indeed with lower target CFL numbers, so it's not a universal solution.
- Wed Aug 24, 2022 10:33 am
- Forum: code_saturne usage
- Topic: Velocity Solution Artefacts
- Replies: 10
- Views: 3544
Re: Velocity Solution Artefacts
Hello. I faced similar but not the same problem. Fluid domain is a rapid channel turn with rectangular head loss / heat source region after it (heat exchnger). Velocity level in head loss region is about 1..2 m/s. Although streamlines look reasonable (near straight due to distributed resistance) in ...
- Wed Aug 17, 2022 8:46 am
- Forum: code_saturne usage
- Topic: Very strange scalability problem on a workstation
- Replies: 13
- Views: 3569
Re: Very strange scalability problem on a workstation
Hello. I think it's just not enough to start run_solver script. I need to execute install/bin/code_saturne run... to start run properly. The problem with MPI options was that I edited the same configuration file in backup directory tree instead of directory Saturne starts from. Now "socket"...
- Tue Aug 16, 2022 5:20 pm
- Forum: code_saturne usage
- Topic: Very strange scalability problem on a workstation
- Replies: 13
- Views: 3569
Re: Very strange scalability problem on a workstation
It's strange but there are lots of iterations set in XML. <time_parameters> <iterations>10000000</iterations> <max_courant_num>2</max_courant_num> <max_fourier_num>10</max_fourier_num> <property label="CourantNb" name="courant_number"/> <property label="FourierNb" name=...
- Tue Aug 16, 2022 4:29 pm
- Forum: code_saturne usage
- Topic: Very strange scalability problem on a workstation
- Replies: 13
- Views: 3569
Re: Very strange scalability problem on a workstation
I tried options in code_saturne.cfg but without visible result. What I've done: 1. Copied etc/code_saturne.cfg.template to / etc/code_saturne.cfg 2. Uncommented and set 2 parameters: ### mpiexec command options mpiexec_opts = --bind-to socket ### Option to pass arguments (usually none, or -args) mpi...
- Tue Aug 16, 2022 11:00 am
- Forum: code_saturne usage
- Topic: Very strange scalability problem on a workstation
- Replies: 13
- Views: 3569
Re: Very strange scalability problem on a workstation
Hello. Thanks for you answer. Regarding OpenMPI version. I tried 3.1.6 and 4.x without evident speed-up. How should I set MPI parameters in Saturne (GUI)? As I can see, GUI sets MPI parameters automatically and runs run_solver script. If I just change this script it will not be persistent for other ...
- Mon Aug 15, 2022 11:02 am
- Forum: code_saturne usage
- Topic: Very strange scalability problem on a workstation
- Replies: 13
- Views: 3569
Re: Very strange scalability problem on a workstation
Hello, thanks for your response. I made some tests with HPCG (test compilation and usage is quite twisted) I ran tests on both machines, with Huananzhi X99-TF and X99-8MD3 boards. Both has C610 chipset, 2678v3 CPU and the same 32 GB 1866 DDR3 REG Samsung memory sticks, but 8MD3 has only 2 slots (64G...