CFD Online Discussion Forums

CFD Online Discussion Forums (https://www.cfd-online.com/Forums/)
-   Siemens (https://www.cfd-online.com/Forums/siemens/)
-   -   Heat flux on a irregular surface (https://www.cfd-online.com/Forums/siemens/53105-heat-flux-irregular-surface.html)

massimo December 4, 2002 05:35

Heat flux on a irregular surface
 
hello, In order to obtain the heat flux through the wall of the casing of machine at a given section, I should create a set of vertex on the exterior casing but the casing is not a regular circle.

I would create a set of vertex on a inner circle and then I would move them to the external casing. I can create the vertex set but I can't move them as I would like.

How can I get it?

raymond December 4, 2002 20:11

Re: Heat flux on a irregular surface
 
Maybe you could generate shell for the exterior case, and then project the vertex onto the shell at prescribed direction.Hope it work.

massimo December 5, 2002 03:33

Re: Heat flux on a irregular surface
 
Ok, I try to do it. Infact I generate shell with the command "pscreate" and I project the vertex with the command "Vproject", but after that the vertex set not lie on exterior casing (external surface). How is possible? Bye

massimo December 5, 2002 09:20

Re: Heat flux on a irregular surface
 
Sorry but I made a mistake in the previouse message. How can I generate shell for the exterior case if the casing is not regular?

With the command "pscreate" I generate shells into normal section plane but not on the external surface as I need. In fact if I want to move the vertex set to the exterior casing from initial inner circle I must create shell around external surface.

How can I get it? Bye

raymond December 5, 2002 22:02

Re: Heat flux on a irregular surface
 
First, I think you have the geometry of the whole case.(in fluid or solid format). Then you can create shell by the command "cfind" or CSET,NEWS,....(SELECT THE CELLS CONTAINS EXTERIOR CASE) VSET,NEWS,CSET,EDGE using the menu "tools ->cell tools" then select "add shells -> surface (new edge vertex set) you can create the shell of extrior case

massimo December 11, 2002 05:55

Re: Heat flux on a irregular surface
 
Thank you for your help, now I can create the shells on the surface and I have found the heat flux through the wall, but it seems there is an error sign because the heat flux is positive where a great heat flux to the air, that is a negative flux, is expected. I have followed your hints: I projected (VPROJ) 72 vertices to the surface shell and I mapped (PMAP VSET CSET,,10) the heat flux values, obtaining the results i told you before. Can you suggest me how to solve this problem? Bye


All times are GMT -4. The time now is 12:39.