how to deal with the surface roughness?

 Register Blogs Members List Search Today's Posts Mark Forums Read

 January 4, 2004, 10:41 how to deal with the surface roughness? #1 maximus Guest   Posts: n/a I have to consider the roughness effect on heat transfer in the flow near the rough wall.and I find the traditional method is to use the boundary layer integration which can include the roughess effect by using the roughness Renolds number.Another method is to modify the log-law of velocity near the wall.here my question is if there is a turbulence model or a wall funtion which can include the roughness effect. thanks.

 January 5, 2004, 06:31 Re: how to deal with the surface roughness? #2 Nicola Guest   Posts: n/a K-omega model by Wilcox provides a simple method to include roughness effect by prescribing a Dirichlet-type boundary condition at wall for omega. For the details, see the Chima's report at www.grc.nasa.gov/WWW/5810/webpage/docs/kw6.pdf. You can also refer to the paper of Wilcox himself: Reassessment of the scale determining equation for advanced turbulence models, AIAA Journal, 26, 1299-1310. Best regards, Nicola

 January 5, 2004, 07:57 Re: how to deal with the surface roughness? #3 maximus Guest   Posts: n/a hi,Nicola,I am very appreciate for your advice.I've got the first paper you told me,but Can you tell me the exact year of the second paper in AIAA Journal(AIAA Journal, 26, 1299-1310,????).And i wonder if it is diffcult to include the roughness effect in k-e model.Because I use the k-e model in my codes,I am trying to find a method to include the roughness effect in k-e model. thanks. maximus.

 January 7, 2004, 05:35 Re: how to deal with the surface roughness? #4 Nicola Guest   Posts: n/a Maximus, I'm sorry for the late answer. The exact reference is Vol. 26 No. 11 November 1988. As far as the k-e model is concerned, I can only tell you that in the case of the Star-CD code, roughness effects are taken into account by wall functions, but I don't know if there is some other method. I suggest you a careful search using google. Best regards, Nicola

 Thread Tools Display Modes Linear Mode

 Posting Rules You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is OffTrackbacks are On Pingbacks are On Refbacks are On Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post velan Open Source Meshers: Gmsh, Netgen, CGNS, ... 1 July 14, 2015 05:54 nishant_hull Open Source Meshers: Gmsh, Netgen, CGNS, ... 18 April 22, 2015 08:43 AlanR OpenFOAM Programming & Development 47 February 21, 2015 12:37 alefem FLOW-3D 6 June 3, 2010 12:49 Chie Min CFX 5 July 12, 2001 23:19

All times are GMT -4. The time now is 15:03.