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Initial value conditions inconsistent with solution.

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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

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