asking usage of velocity inlet

teguhtf · November 21, 2009, 18:21

Hi All
I read tutorial on http://courses.cit.cornell.edu/fluent/plate/step3.htm. I see something odd. The BC of Inflow is Velocity inlet & The fluid is ideal gas. I think Velocity inlet is used for incompressible flow. Can you explain it??
Thank You,
teguh

enry · November 22, 2009, 06:32

Hi,
velocity inlet is the B.C. of inflow, as you write. Why do you think that condition as incompressible flow? I think that condition only as a condition that you can impose.

teguhtf · November 22, 2009, 09:20

Hello,
Thanks for replying.
I have run that simulation. It run completely. But there is warning on FLUENT when I choose velocity inlet as inflow. In FLUENT manuals, compressible flow can be solved by using mass flow inlet or like pressure inlet. I'm afraid if i impose the boundary, there will be incorrect result.
I see if compressible flow can be assumed as incompressible flow if the velocity < 0.3 Mach. However there is still error, isn't it??
teguh

enry · November 22, 2009, 10:28

As far as I know, I don't think that the error is due to velocity inlet BC.
I try to solve a simple plane plate imposing supersonic velocity inlet, and fluent doesn't report any error (even if the result may be wrong....) . What tipe of error fluent report for your problem?

teguhtf · November 23, 2009, 06:39

Well, There is warning when i choose Velocity Inlet as inlet BC. I think it can cause error on my simulation. Am I wrong??
For case high mach number. There is option pressure far field or pressure inlet (I just read some tutorials on studentFLUENT). Is it OK if we use velocity inlet to simulate compressible flow for high mach number?? Can you tell me your reference??
Thanks for helping
teguh

enry · November 24, 2009, 03:47

Here there are all fluent guide and manual. Try to visit it.

http://hpce.iitm.ac.in/website/Manua...help/index.htm

There are also some tutorials.

November 21, 2009, 18:21	asking usage of velocity inlet	#1
teguhtf Senior Member teguh hady Join Date: Aug 2009 Location: Saga, Japan Posts: 222 Rep Power: 17	Hi All I read tutorial on http://courses.cit.cornell.edu/fluent/plate/step3.htm. I see something odd. The BC of Inflow is Velocity inlet & The fluid is ideal gas. I think Velocity inlet is used for incompressible flow. Can you explain it?? Thank You, teguh __________________ Now Or Never!!! Last edited by teguhtf; November 21, 2009 at 19:57. Reason: Correcting

November 22, 2009, 09:20		#3
teguhtf Senior Member teguh hady Join Date: Aug 2009 Location: Saga, Japan Posts: 222 Rep Power: 17	Hello, Thanks for replying. I have run that simulation. It run completely. But there is warning on FLUENT when I choose velocity inlet as inflow. In FLUENT manuals, compressible flow can be solved by using mass flow inlet or like pressure inlet. I'm afraid if i impose the boundary, there will be incorrect result. I see if compressible flow can be assumed as incompressible flow if the velocity < 0.3 Mach. However there is still error, isn't it?? teguh __________________ Now Or Never!!!

November 23, 2009, 06:39		#5
teguhtf Senior Member teguh hady Join Date: Aug 2009 Location: Saga, Japan Posts: 222 Rep Power: 17	Well, There is warning when i choose Velocity Inlet as inlet BC. I think it can cause error on my simulation. Am I wrong?? For case high mach number. There is option pressure far field or pressure inlet (I just read some tutorials on studentFLUENT). Is it OK if we use velocity inlet to simulate compressible flow for high mach number?? Can you tell me your reference?? Thanks for helping teguh __________________ Now Or Never!!! Last edited by teguhtf; November 23, 2009 at 06:41. Reason: correcting

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November 22, 2009, 06:32		#2
enry Senior Member Herman Join Date: Nov 2009 Posts: 122 Rep Power: 16	Hi, velocity inlet is the B.C. of inflow, as you write. Why do you think that condition as incompressible flow? I think that condition only as a condition that you can impose.

November 22, 2009, 10:28		#4
enry Senior Member Herman Join Date: Nov 2009 Posts: 122 Rep Power: 16	As far as I know, I don't think that the error is due to velocity inlet BC. I try to solve a simple plane plate imposing supersonic velocity inlet, and fluent doesn't report any error (even if the result may be wrong....) . What tipe of error fluent report for your problem?

November 24, 2009, 03:47		#6
enry Senior Member Herman Join Date: Nov 2009 Posts: 122 Rep Power: 16	Here there are all fluent guide and manual. Try to visit it. http://hpce.iitm.ac.in/website/Manua...help/index.htm There are also some tutorials.