CFD Online URL
[Sponsors]
Home > Forums > FLUENT

How to find Mean Nusselt Number?

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

Reply
 
LinkBack Thread Tools Display Modes
Old   December 21, 2012, 04:00
Default How to find Mean Nusselt Number?
  #1
New Member
 
Abhishek
Join Date: Dec 2012
Posts: 1
Rep Power: 0
abhishek4890 is on a distinguished road
I am doing an computational analysis on natural convection heat transfer through rectangular fins attached to a wall. After the simulation, Surface Nusselt number for hot wall which I am getting in higher than (twice) the experimental results. The way I am following for finding the mean nusselt number is : Report--> Surface Integrals-->Facet Average-->Wall Fluxes-->Surface Nusselt number.
Please provide me the solution. Also let me know whether I am using the right way of finding the nusselt number or not. If not then please provide me an alternate way of finding the Average Nusselt Number.
abhishek4890 is offline   Reply With Quote

Old   December 22, 2012, 03:24
Default
  #2
Senior Member
 
Lucky Tran
Join Date: Apr 2011
Location: Orlando, FL USA
Posts: 526
Rep Power: 10
LuckyTran is on a distinguished road
Two things:

1) Heat transfer coefficient needs a reference temperature
2) Nusselt number needs a reference length scale.

Both of these reference quantities are specified on the reference values task pane. Did you remember to specify them?

I have always used area-weighted average and not facet average, but I believe they yield similar results. You should be able to get the average Nusselt number the way you are doing.
LuckyTran 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
Average Nusselt Number kamran651 FLUENT 7 August 20, 2014 19:58
same geometry,structured and unstructured mesh,different behaviour. sharonyue OpenFOAM Running, Solving & CFD 13 January 2, 2013 23:40
there is a problem with fully developed Nusselt number eeman Fluent UDF and Scheme Programming 4 September 24, 2012 02:36
CFX problem in ubuntu (linux) Vigneshramaero CFX 0 July 13, 2012 11:22
snappyHexMesh won't work - zeros everywhere! sc298 OpenFOAM Native Meshers: snappyHexMesh and Others 2 March 27, 2011 22:11


All times are GMT -4. The time now is 22:32.