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

Viscous work term query

Register Blogs Community New Posts Updated Threads Search

Like Tree1Likes
  • 1 Post By ghorrocks

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   December 6, 2010, 04:34
Default Viscous work term query
  #1
siw
Senior Member
 
Stuart
Join Date: Jul 2009
Location: Portsmouth, England
Posts: 739
Rep Power: 26
siw will become famous soon enough
Hi,

For the total energy equation there's a check box to include the work due to viscous stresses term in the energy equation.

Why is it that by default this term is omitted from the energy equation and requires being separately activated? What sort of simulations require the total energy equation but not the viscous work term (it's not a Euler situation)? Would it not be better to solve the whole equation by default?

My simulation (Mach no. 0.85, Re no. 5x10^6) shows a 20 deg C higher surface temperature (on average) with the viscous work term included (see image).

Thanks
Attached Images
File Type: jpg 1.JPG (57.5 KB, 116 views)

Last edited by siw; December 6, 2010 at 07:14. Reason: Added image
siw is offline   Reply With Quote

Old   December 6, 2010, 07:41
Default
  #2
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,854
Rep Power: 144
ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
Viscous work is insignificant for most compressible flow models. Looks like you have found one where it is not. There is no point adding extra terms in the equation when they do not do anything for most models.
C. Okubo likes this.
ghorrocks is offline   Reply With Quote

Reply


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 Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
VISCOUS DISSIPATION ROBERT Main CFD Forum 30 May 29, 2019 05:21
question about term representation titio OpenFOAM Running, Solving & CFD 0 May 4, 2009 10:17
What is the Boussinesq Term in Momentum Equation CFDtoy Main CFD Forum 0 August 11, 2008 10:56
UDF's - linearizing a negative source term Steve Howell FLUENT 1 March 18, 2001 17:21
Why FVM for high-Re flows? Zhong Lei Main CFD Forum 23 May 14, 1999 14:22


All times are GMT -4. The time now is 19:00.