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.

Microfluidic pipe outlet with free velocity profile?

Please login with a confirmed email address before reporting spam

Hello everyone,

I am modeling the flow within a microfluidic system, let's just say it is a straight pipe for the purposes of the question. The direction of the flow could be towards either side of the pipe. I set the velocity/pressure at the inlet, and record flow in the outlet. The outlet flow should be fully developed when flow is from the inlet to the outlet (pipe length > entrance length), but it should be completely undeveloped when the flow is from the outlet to the inlet (outlet is the true entrance to pipe). Everything I have tried gives me only a fully developed flow, no regardless of the direction of the flow.

Is there a way to have the outlet flow be either developed/undeveloped depending on the circumstance? I am currently running separate stationary simulations, but eventually I will run a single time-dependent where the flow direction will fluctuate, so ideally the fix would be the same for both flow directions.

Thank you, Christos


0 Replies Last Post Mar 8, 2020, 5:46 PM EDT
COMSOL Moderator

Hello Christos Michas

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.