all-results-pressure shows constant 0's

[Radhika Kulkarni]

Hello!

I am working on the Aortofemoral Normal - 2 tutorial, and after running the simulation, I get all 0's in my pressure file. When I upload my files in Paraview, I get pressure and velocity for the first time step only (0), but the pressure is 0. For the other timesteps, the option of pressure and velocity isn't there at all.

I have attached my simulation files below. Please do let me know if you cannot view it. Any help would be appreciated!

[David Parker]

Hi Radhika,

Looking at the all_results-pressures.txt file I only see a single step, step 0

Code: Select all

step    cap_Aorta_Smoothed      cap_Aorta_Smoothed_2    cap_Brachiocephalic_Right_Subclavian    cap_Celiac_Hepatic      cap_Common_External_Femoral     cap_Left_Common_Carotid cap_Left_Internal       cap_Left_Profunda       cap_Left_Profunda_2     cap_Left_Renal  cap_Left_Subclavian     cap_Right_Common_Carotid        cap_Right_Internal      cap_Right_Profunda      cap_Right_Profunda_2    cap_Right_Renal cap_SMA cap_Splenic
00000   0.000000        0.000000        0.000000        0.000000        0.000000        0.000000        0.000000        0.000000        0.000000        0.000000        0.000000        0.000000        0.000000        0.000000        0.000000        0.000000        0.000000        0.000000      

You will need to run the simulation for a few hundred time steps to see anything interesting.

Cheers,
Dave

[Radhika Kulkarni]

Hi David,

I actually have the number of timesteps set to 3200 (like said in the tutorial). In my simulation converted results, I have files for each time step as well, so I'm not sure what the issue is! I have tried simply running 10 timesteps, but it gives me all 0s again.

[David Parker]

Hi Radhika,

I'm not sure what is going on. If you can put your SV project someplace I can download it I'll have a look.

Cheers,
Dave

[Radhika Kulkarni]

Thank you so much! Here is the link:

https://drive.google.com/drive/folders/ ... sp=sharing

[David Parker]

Hi Radhika,

This is a huge mesh! How many processors did you run it on? How did you convert the results?

I was able to run the simulation fine for a new mesh with a smaller number of elements so I think the solver parameters are ok. A histor.dat file is created by the simulation, please post that file here.

Cheers,
Dave

[Radhika Kulkarni]

Hi David,

Yes, I did struggle with the meshing. It kept saying I have a facet and segment intersecting. I tried doing iterations of Local Decimation, lap. smooth, and cstr. smooth, but I do not think it worked. That is why I played around with the Max Edge Size until I got a mesh made.

I did not use MPI or processors. I simply clicked "Run Simulation". To convert my results, I did timestep of 0 to 3200 with increment 400.

May I know how you were able to create the mesh, and what you mean by "smaller number of elements"?


I also do not have a histor file in my folder!

[David Parker]

Hi Radhika,

Facet and segment intersecting are typical meshing errors, I need to look at what is causing these errors some day.

I meshed with a max edge size 0.2 without boundary layer.

Not running with MPI must have taken a week to finish? I think there is a problem with svSolver running without MPI, I can't confirm though without looking at the histor.dat file. Try rerunning the simulation with MPI using four processors.

Cheers,
Dave

[Radhika Kulkarni]

Hmm.. I definitely did not wait a week! Max was 15 minutes.. I'm working on another project right now and I've been having the same problem.

I redid the mesh to 0.2 and am running the simulation now using 4 Processes, but the simulation has been stuck on 0% for a while now. I'm not sure how long this should be taking, but I thought I'd just ask. Do I wait until it's finished to Convert Results?

I've attached the histor file that was under 4_procs_case on Google Drive.

https://drive.google.com/drive/folders/ ... sp=sharing

[David Parker]

Hi Radhika,

Your simulations are failing for some reason. What OS are you running on and what SV and svSolver versions are you using?

Cheers,
Dave