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position of inlet velocity

Posted 11.03.2012, 23:52 GMT-4 Version 4.2a 3 Replies

Siva Kumar Manickam
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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 12.03.2012, 22:24 GMT-4
Jaap Verheggen
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Posted: 1 decade ago 12.03.2012, 10:35 GMT-4
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
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Posted: 1 decade ago 12.03.2012, 11:21 GMT-4
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

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Siva Kumar Manickam
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Posted: 1 decade ago 12.03.2012, 22:24 GMT-4
I request Dr. Ivar to join us in enlightening us....Please....
I request Dr. Ivar to join us in enlightening us....Please....

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