Menu

Discussion Forum

New Discussion
Filter

Note: This discussion is about an older version of the COMSOL Multiphysics® software. The information provided may be out of date.

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.

position of inlet velocity

Posted Mar 11, 2012, 11:52 p.m. EDT Version 4.2a 3 Replies

Siva Kumar Manickam
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Dear all,
I am doing a simple 2d spf flow past circular cylinder. I see my results (particularly reacf(v)) highly depending on position of inlet. which is correct distant at which inlet should be placed before a circular wall?.
Thanks in advance
Siva
3 Replies Last Post Mar 12, 2012, 10:24 p.m. EDT
Jaap Verheggen
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago Mar 12, 2012, 10:35 a.m. EDT
What are your inlet conditions? Would be good to set the inlet velocity and make an exponential profile, like vtot*s*(1-s)

You can check the surface plots for velocity, the flow should be developed, not changing before it hits the cilinder.

What are your inlet conditions? Would be good to set the inlet velocity and make an exponential profile, like vtot*s*(1-s) You can check the surface plots for velocity, the flow should be developed, not changing before it hits the cilinder.
Siva Kumar Manickam
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago Mar 12, 2012, 11:21 a.m. EDT
Dear Verheggen,
Thanks for your reply. I understand that.
actually my flow is calculated due to oscillating cylinder using coupled differential equation as in the 'falling sand' tutorial (plz see the attached figure). The inlet velocity isQdot, which is calculated using reacf(v) from the body-fitted frame. My results varies 2e3 times the theoretical results. But ironically my results changes a lot depending on the position of inlet. I have no clue.
thanks again for your thoughts.
Siva
Dear Verheggen, Thanks for your reply. I understand that. actually my flow is calculated due to oscillating cylinder using coupled differential equation as in the 'falling sand' tutorial (plz see the attached figure). The inlet velocity isQdot, which is calculated using reacf(v) from the body-fitted frame. My results varies 2e3 times the theoretical results. But ironically my results changes a lot depending on the position of inlet. I have no clue. thanks again for your thoughts. Siva

Attachments:

Siva Kumar Manickam
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago Mar 12, 2012, 10:24 p.m. EDT
I request Dr. Ivar to join us in enlightening us....Please....
I request Dr. Ivar to join us in enlightening us....Please....

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