CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > CFX

The question about Y+

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

Reply
 
LinkBack Thread Tools Display Modes
Old   November 4, 2002, 04:24
Default The question about Y+
  #1
rambol
Guest
 
Posts: n/a
Hi,everyone.If I use low reynolds k-e turbulent model in gas-solid two-phase flow,Should I ensure the Y+ less than 1.0 for the gas and solid phase respectively?I have used fine mesh and the grid is 0.08mm at the bounday.but it diverged after some steps. who can give me some advice?thanks
  Reply With Quote

Old   November 6, 2002, 05:43
Default Re: The question about Y+
  #2
Drona
Guest
 
Posts: n/a
Hi Rambol,

I have been pondering over Y+ issues lately, so I thought I should write. I think you need to find out the boundary layer thickness(laminar sublayer) first and then decide on number of grid points within the layer. The CFX-TASCflow theory manual has a chapter on grid geneartion guidelines but not very clear. You may want to read that anyway. If your domain is a complex one, you will be hard pressed to ensure a desirable Y+ value everywhere in the domain.

Let's know if you have any joy with it.

Drona
  Reply With Quote

Old   November 7, 2002, 10:40
Default Re: The question about Y+
  #3
rambol
Guest
 
Posts: n/a
Thank you,Drona I use cfx-4.3 and calculate the dense gas-solid flow in a pipe.The minimum mesh near to the wall is 0.8mm .The result shows that the value of YPlus of gas is 0.8 and solid is 1.74e+05.I think it is very difficult to get the value of yplus less than 1 to solid phase through refining mesh.I use low Renolds k-e turbulent model. So should I must achieve the criterion for both phases that yplus should be less than 1 in low Renolds k-e turbulent model?
  Reply With Quote

Reply

Thread Tools
Display Modes

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 Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Unanswered question niklas OpenFOAM 2 July 31, 2013 16:03
internal field question - PitzDaily Case atareen64 OpenFOAM Running, Solving & CFD 2 January 26, 2011 16:26
Question about Table applicaiton. universez OpenFOAM Running, Solving & CFD 0 January 12, 2010 21:31
CHANNEL FLOW: a question and a request Carlos Main CFD Forum 4 August 23, 2002 05:55
question K.L.Huang CD-adapco 1 March 29, 2000 04:57


All times are GMT -4. The time now is 03:54.