Menu

Discussion Forum

New Discussion
Filter

Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

Initial value conditions inconsistent with solution.

Posted Jul 8, 2017, 12:37 p.m. EDT Fluid & Heat, Computational Fluid Dynamics (CFD) Version 5.1 0 Replies

Arturo Sosa Lombardo
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

I'm simulating laminar flow in a straight pipe with both stationary and time dependent study. The simulations ran without issue, however the results are questionable. Reason one, the relative error is 0.599%. Second reason, the velocity slices in the post processing result shows a velocity within the pipe at t0 when it was specified in the initial values to have 0 velocity in the 3 directions. I've tried messing with the inlet and outlet boundary conditions but that increases the relative error. I'm really curious why the relative error is that big on a simple problem.

BC:
The reference pressure, initial value pressure, and outlet pressure are 0. There is a no slip condition on the walls, inlet velocity is normal flow with a specified velocity, outlet is also normal flow with no suppression of back flow.

If anyone could clear up my issues please let me know.Thank you for your time.

I couldn't upload the file due to file size error. The link is below:

drive.google.com/file/d/0B8u6NF3s2AoDT1hlUExSMVpyZTA/view?usp=sharing
0 Replies Last Post Jul 8, 2017, 12:37 p.m. EDT
COMSOL Moderator

Hello Arturo Sosa Lombardo

Your Discussion has gone 30 days without a reply. If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help.

If you do not hold an on-subscription license, you may find an answer in another Discussion or in the Knowledge Base.

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.

Suggested Content