CFD Online Logo CFD Online URL
Home > Forums > Main CFD Forum

How to mesh the 1st grid point?

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

LinkBack Thread Tools Display Modes
Old   October 7, 2007, 09:44
Default How to mesh the 1st grid point?
Posts: n/a
How to mesh the 1st grid point?

I am very young to CFD world. I'm trying to use oodles to learn LES techniques. Now I have some problems about meshing.

I saw a paper on flow over a cylinder using Fluent, its meshing guideline is like this, Reynolds Number Flow Regime Yplus/First Cell Height Re < 1000 Laminar First Cell Height = Cylinder Radius/24 1000 < Re < 20000 Turbulent, Enhanced Wall Treatment Yplus < 10 Re > 20000 Turbulent, Standard Wall Functions Yplus > 30

Q-1. Why mesh like this? Is there any references on how-to mesh under LES and DNS? Sorry, I did not find help from <grid generation> and <Fluent Mannual>...

Q-2. Is that mean: If I use wall function, then I can set the 1st grid point at the place of y+=30? If I use not wall function, then I should set the 1st grid point at the place of y+=1?

Q-3. I heard "Laminar LES"=DNS, what does it mean? Is it mean that their mesh is identical?

Q-4. I see that the 1st grid point is decided by the flow state, but When I predict flow around a building on a certain Re for example, the laminar and turbulence coexist around the building, then how to decide the 1st grid point?

Thanks for your time

  Reply With Quote

Old   October 8, 2007, 02:27
Default Re: How to mesh the 1st grid point?
Posts: n/a
take a look at this..
  Reply With Quote


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
3D Hybrid Mesh Errors DarrenC ANSYS Meshing & Geometry 11 August 5, 2013 06:42
2d irregular grid Remy Main CFD Forum 1 December 22, 2008 05:49
fluent add additional zones for the mesh file SSL FLUENT 2 January 26, 2008 12:55
UDF to define source term at every grid point Ralf Schmidt FLUENT 0 September 21, 2006 11:32
unstructured vs. structured grids Frank Muldoon Main CFD Forum 1 January 5, 1999 11:09

All times are GMT -4. The time now is 11:35.