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

Seeking guidance in how to do: Mesh Independence Studies

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

Reply
 
LinkBack Thread Tools Display Modes
Old   March 4, 2015, 18:16
Exclamation Seeking guidance in how to do: Mesh Independence Studies
  #1
Member
 
Join Date: Jan 2015
Location: United Kingdom
Posts: 38
Rep Power: 3
Jeeloong is on a distinguished road
Dear Experts,

I am so confused with mesh independency studies.

According to some I should varies the mesh densities without considering the y+ really much when doing mesh independence and after I get a stable solution (No changes in variable), I then move on the change the mesh side near the BL to capture the details.

My question is should I make 5 cases with same y+ but different mesh densities, run it and test the dependency

Or

run different mesh densities without considering y+(varies for all cases)

I was acknowledged that the mesh independence studies is numerically means that the core flow does not change?

Let say I keep on discretise it but somehow the different y+ for each cases will affect the solution for monitoring point right?

Thanks

Regards
JL
Jeeloong is offline   Reply With Quote

Old   March 6, 2015, 15:21
Default
  #2
Senior Member
 
Matt
Join Date: Aug 2014
Posts: 579
Rep Power: 7
MBdonCFD is on a distinguished road
That choice really boils down to what your figures of merit are (i.e. what are you trying to learn?). If the variables that you are looking at during your convergence studyare driven by boundary layer mesh (like drag for example) then you definitely want to make y+ a part of that process. If you are looking at something like mass flow (or even lift in some cases) that is less dependent upon boundary layer mesh then you can probably get away with neglecting it.

The safe bet, and what I usually tend to do, is make succesivly finer mesh iterations that account for both simultaneously that way you know that each model in the convergence study is as appropraite as the others.
MBdonCFD is offline   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
No layers in a small gap bobburnquist OpenFOAM Native Meshers: snappyHexMesh and Others 6 August 26, 2015 09:38
SnappyHexMesh no layers and no decent mesh for complex geometry pizzaspinate OpenFOAM Mesh Utilities 1 February 25, 2015 08:05
Layers:problem with curvature giulio.topazio OpenFOAM Native Meshers: snappyHexMesh and Others 10 August 22, 2012 09:03
Grid Independence of Boundary layer Luigi_ Main CFD Forum 0 December 14, 2011 14:42
Mesh Independence and Y + sam FLUENT 1 September 13, 2006 05:50


All times are GMT -4. The time now is 17:19.