help me as soon as possible please

happy · September 21, 2011, 22:11

hi all,,,,,

I'm gonna to do 2 D simulation in CFX for axisymmetry channel ( large pipe). I thought that I should to draw the half of my geometry only. is this correct??? any way, I draw a wadge with 2.5 degree in ZY plane and then I extrude it. Is this action correct or not?my channel is symmetry around X axis, so what I should to do to use only the half of my geometry for my simulation, and then could you please tell me about the BCs?
My question also about why when the user want to simulate axisymmetry body in 2 D should draw wedge???????????? really I want to know.

please, do not let me wait long time I need any one to help me ASAP.
see below links please,,,

Picture file : http://ifile.it/sfzx3h4
ANSYS file : http://ifile.it/odhai4f

Best Regards

Lance · September 22, 2011, 02:57

CFX does not have a 2D solver so you'll need to do a wedge and extrude (making it 3D) if you are modeling axi symmetric stuff. I couldnt see your pictures, but what about symmetry boundary conditions on the sides?

ghorrocks · September 22, 2011, 06:13

This FAQ discusses the 2D question.

http://www.cfd-online.com/Wiki/Ansys..._simulation.3F

happy · September 23, 2011, 02:18

hi and thanks for your inputs

Actually, I use the revolve action to create angle with 1degree. My question now is for axisymmetric geometry, I should to revolve the half of my geometry around the symmetry plane ( not a whole the geometry). for example, if my pipe is 4 m in diam and 8 in height so my 2 D sketch should be 2m*8m. Is this correct????. please I'm waiting to hear from you.

By the way, what does mean the periodic boundaries here exactly? how I can found them into set up stage?as I know this term is for the interface setting, is it right?

help me please.

Regards

ghorrocks · September 23, 2011, 07:34

Yes, only half the geometry.

Periodic boundaries are a form of interface. Think of it as what goes in one side comes out the other. You might get a better description with Google.

September 21, 2011, 22:11	help me as soon as possible please	#1
happy Senior Member Safia Join Date: Oct 2010 Location: Australia Posts: 161 Rep Power: 15	hi all,,,,, I'm gonna to do 2 D simulation in CFX for axisymmetry channel ( large pipe). I thought that I should to draw the half of my geometry only. is this correct??? any way, I draw a wadge with 2.5 degree in ZY plane and then I extrude it. Is this action correct or not?my channel is symmetry around X axis, so what I should to do to use only the half of my geometry for my simulation, and then could you please tell me about the BCs? My question also about why when the user want to simulate axisymmetry body in 2 D should draw wedge???????????? really I want to know. please, do not let me wait long time I need any one to help me ASAP. see below links please,,, Picture file : http://ifile.it/sfzx3h4 ANSYS file : http://ifile.it/odhai4f Best Regards

September 23, 2011, 02:18	I know already what you tell me here	#4
happy Senior Member Safia Join Date: Oct 2010 Location: Australia Posts: 161 Rep Power: 15	hi and thanks for your inputs Actually, I use the revolve action to create angle with 1degree. My question now is for axisymmetric geometry, I should to revolve the half of my geometry around the symmetry plane ( not a whole the geometry). for example, if my pipe is 4 m in diam and 8 in height so my 2 D sketch should be 2m*8m. Is this correct????. please I'm waiting to hear from you. By the way, what does mean the periodic boundaries here exactly? how I can found them into set up stage?as I know this term is for the interface setting, is it right? help me please. Regards

September 22, 2011, 02:57		#2
Lance Senior Member Lance Join Date: Mar 2009 Posts: 669 Rep Power: 22	CFX does not have a 2D solver so you'll need to do a wedge and extrude (making it 3D) if you are modeling axi symmetric stuff. I couldnt see your pictures, but what about symmetry boundary conditions on the sides?

September 22, 2011, 06:13		#3
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,703 Rep Power: 143	This FAQ discusses the 2D question. http://www.cfd-online.com/Wiki/Ansys..._simulation.3F

September 23, 2011, 07:34		#5
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,703 Rep Power: 143	Yes, only half the geometry. Periodic boundaries are a form of interface. Think of it as what goes in one side comes out the other. You might get a better description with Google.