circumferential velocity

keeper · August 6, 2010, 03:39

Hello, I have one question. Can settings in Pre-Processing affect variables able to calculate in Post-Processing?? I have similar cases but in one I can't calculate circumferential velocity. Can anybody help me please??

ghorrocks · August 6, 2010, 05:55

Yes, you won't have turbulence variables available if you choose a laminar flow model. Same applies to any other model which introduces new variables.

If all you want is velocities in a different frame of reference then this is easily calculated in the post processor, regardless of what preprocessor options were chosen.

keeper · August 6, 2010, 06:19

I set up SST turbulence model. Is there any option in pre-processor how to choose variables which will be displayed in post-processor?

Claudia · August 6, 2010, 08:58

There is a different in post if you open *.res or *.bak files. In case of a bak-file there might be some variables missing if you didn't choose a full backup in pre.
But if you have a *.res file it is as Glenn explained, the variables in post depend on the models you have chosen in pre (as laminar or turbulent for example).

ghorrocks · August 7, 2010, 06:52

The variables which are put into the results file are set in the output tab in CFX-Pre. You can make it anything from all variables to nothing.

bharath · August 9, 2010, 21:46

If you want circumferential velocity specifically you can use turbo mode in cfx post and define your rotation axis then you select calculate velocity components. now you can see circumferential velocity variable in selection list.

keeper · August 10, 2010, 03:14

I need to get circumferential velocity because I need to determine velocity angle on impeller but I can't find it. Can't see anything wrong

bharath · August 11, 2010, 13:22

after use of turbo mode you can get circumferential velocity.if you can't send me your result file to bharath102015@yahoo.co.in.i will check it out

keeper · August 12, 2010, 03:50

thank you all for your advices. bharath, I really appraise your help but unfortunately I can't send any data due to confidence... But your advices help me very much and I already solved problem.

August 6, 2010, 03:39	circumferential velocity	#1
keeper Senior Member Join Date: Jul 2010 Posts: 152 Rep Power: 15	Hello, I have one question. Can settings in Pre-Processing affect variables able to calculate in Post-Processing?? I have similar cases but in one I can't calculate circumferential velocity. Can anybody help me please??

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August 6, 2010, 05:55		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,700 Rep Power: 143	Yes, you won't have turbulence variables available if you choose a laminar flow model. Same applies to any other model which introduces new variables. If all you want is velocities in a different frame of reference then this is easily calculated in the post processor, regardless of what preprocessor options were chosen.

August 6, 2010, 06:19		#3
keeper Senior Member Join Date: Jul 2010 Posts: 152 Rep Power: 15	I set up SST turbulence model. Is there any option in pre-processor how to choose variables which will be displayed in post-processor?

August 6, 2010, 08:58		#4
Claudia Member Join Date: Mar 2009 Posts: 38 Rep Power: 17	There is a different in post if you open .res or .bak files. In case of a bak-file there might be some variables missing if you didn't choose a full backup in pre. But if you have a *.res file it is as Glenn explained, the variables in post depend on the models you have chosen in pre (as laminar or turbulent for example).

August 7, 2010, 06:52		#5
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,700 Rep Power: 143	The variables which are put into the results file are set in the output tab in CFX-Pre. You can make it anything from all variables to nothing.

August 9, 2010, 21:46		#6
bharath Senior Member Bharath kumar Join Date: Apr 2009 Posts: 169 Rep Power: 17	If you want circumferential velocity specifically you can use turbo mode in cfx post and define your rotation axis then you select calculate velocity components. now you can see circumferential velocity variable in selection list.

August 10, 2010, 03:14		#7
keeper Senior Member Join Date: Jul 2010 Posts: 152 Rep Power: 15	I need to get circumferential velocity because I need to determine velocity angle on impeller but I can't find it. Can't see anything wrong

August 11, 2010, 13:22		#8
bharath Senior Member Bharath kumar Join Date: Apr 2009 Posts: 169 Rep Power: 17	after use of turbo mode you can get circumferential velocity.if you can't send me your result file to bharath102015@yahoo.co.in.i will check it out

August 12, 2010, 03:50		#9
keeper Senior Member Join Date: Jul 2010 Posts: 152 Rep Power: 15	thank you all for your advices. bharath, I really appraise your help but unfortunately I can't send any data due to confidence... But your advices help me very much and I already solved problem.