simtk.org

Hey SimVascular team,

I have been following along with the simulation tutorial that you guys provide but have been unable to get the tube with variable walls to satisfy continuity. After the simulation completes I open the converted results in ParaView and then extract the inlet and outlet to calculate the surface flow for each.

I defined my inlet to have a steady flow of -10 cc/sec but at the outlet the flow will vary from -26 to -220 cc/sec over the course of my simulation (1 period, 1000 time steps, 0.001 second length). other than the inlet flow, I used all of the values supplied in the tutorial. Do you guys have any suggestions on what might be the issue or do you need any additional information?

Thanks,
Brennen

Hi Brennen,

I'm not sure what caused it. Could you send the whole project to me? I'll take a look.

Thanks,
SimVascular Development Team

How would you like me to send you the file? it is to large to upload as an attachment on the forum.

You can put into a dropbox and share the link with me (hongzhi@stanford.edu)

SimVascular Development Team

I checked your files. I think you didn't save the project after simulations, so i couldn't see the parameter values you used.

But one reason I think is, for steady_rcr_variable, you didn't use the simulation result from steady_rcr as initial condition

check this example as below about how set up initial conditions(IC) based on previous simulation results
http://simvascular.github.io/docsFlowSo ... l#example3

SimVascular Development Team

I must have uploaded the wrong files, because I am confident that I had done that on my simulations.

Regardless, I reran and saved stead_rcr and steady_rcr_variable. however, I am still getting inlet and outlet flows that are unreasonably different. I have uploaded these files to the drive if you would not mind taking a look at them.

Thanks,
Brennen

I found out the initial displacement is so large at displacement.vtp. I'm asking someone else in our lab to take a look at the issue.
What OS and what version of SimVascular are you using?

SimVascular Development Team

I am running Simvascular 3.0 on Ubuntu 14.04

Since your initial displacement was so large, we think the pressure your used in "Wall Properties" was 1333300 which is way beyond the physiological range. You need to use some value close to 13333.

For simulation with deformable walls, you can try to use "GMRES" for svLS Type in "Solver Parameters"

SimVascular Development Team

Sorry, you should use 133300.