CFD Online Logo CFD Online URL
Home > Forums > ANSYS

Change parameter and run cases parallel

Register Blogs Members List Search Today's Posts Mark Forums Read

LinkBack Thread Tools Display Modes
Old   July 29, 2011, 10:27
Default Change parameter and run cases parallel
Join Date: Jul 2011
Posts: 48
Rep Power: 8
lingdeer is on a distinguished road

I am running 2 way FSI on blood vessel using ANSYS workbench and CFX. It's a cylinder, 20mm diameter, 200mm length, 3mm thickness.
I have a lot of issues even start to run the simulations, and always get this error: "Fatal error occurred when requesting Total Mesh Displacement for Interface"

Only one case that works so far, I impose a pressure pulse of 0.01s (peak 1600 Pa) and 0.01-0.02s 0 Pa, I used both Hex meshes for solid and fluid.
Time step = 0.001s, Step end time = 0.02s. And this is the only case that works (Young's modulus = 1.33e7). Outlet boundary is opening type, pressure =0.

Since I m trying to make it more physiologic, I need to lower down Young's modulus to 1.33e5 - 1.33e6. But once I change that the error that I mentioned show up.

Also, I am trying to impose velocity/flow boundary conditions because that's something I need to do eventually. However, I tried different times and same error stopped my simulations again at the first time step. I read some forum threads but I didnt get the exact solution of my problem. So I have a couple of questions hope anyone can help me with:

1) Since I want to play with different parameters: e.g. mesh type, mesh size, time step, inlet outlet profiles on the same ansys workbench file to fine tune to the condition I need, I don't want to setup cases for each of them. Instead, I want to run them all at the same time as I can run on different nodes on my server. I wonder is there anyway to do that, instead of creating many different workbench file to do that?

2) How can I determine the best time step of my problem? (I guess if I can figure out the 1st problem then I can try running with different timesteps here)

3) I wonder do I need to add some sort of stability/source term at my FSI boundary? I am a newbie to FSI simulations so if anyone can offer me some guidance it would be greatly appreciated.

Thanks a tonne in advance!
lingdeer is offline   Reply With Quote


cfx, fsi, source term, time step, workbench

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
Finding vector parallel tolerance Dimitris CFX 3 June 13, 2017 11:14
Running in parallel error Madeleine P. Vincent OpenFOAM Running, Solving & CFD 0 May 7, 2011 08:44
Parallel Run on dynamically mounted partition braennstroem OpenFOAM Running, Solving & CFD 14 October 5, 2010 14:43
Issue with running in parallel on multiple nodes daveatstyacht OpenFOAM 7 August 31, 2010 17:16
RPM in Wind Turbine Pankaj CFX 9 November 23, 2009 05:05

All times are GMT -4. The time now is 19:16.