Nusselt number

Studentdrak · March 23, 2012, 06:31

can anyone suggest me how to calculate the nusselt number from results?

I have a duct with L/D = 62 , ReD = 8100, all walls at constant heat flux. I want to cross check my results with Dittus- Boelter equation.

pl. do reply

ghorrocks · March 25, 2012, 07:28

Define a variable in CFD-Post with the equation for Nussult number. Then you can use this variable as a normal results file variable -you can plot it, get min/max, integrate it, graph it against something etc etc

pritam1688 · March 27, 2012, 10:45

i tried but not succeded in creating this varible with formula.......
please help

Studentdrak · March 27, 2012, 11:55

how did u try pritam?

what is your formula?

lffabiani · March 27, 2012, 16:06

On CFD-POST first create an expression

Example: sqrt(Velocity w^2)

and name it ("nusselt", "my expression", or whatever)

Then on variables, create a new variable (also name it as you wish) and point the "expression" field to the expression you just created.

March 23, 2012, 06:31	Nusselt number	#1
Studentdrak Member Join Date: Aug 2011 Posts: 53 Rep Power: 16	can anyone suggest me how to calculate the nusselt number from results? I have a duct with L/D = 62 , ReD = 8100, all walls at constant heat flux. I want to cross check my results with Dittus- Boelter equation. pl. do reply

March 27, 2012, 10:45	how to create variable Nussult no in cfd post	#3
pritam1688 New Member pritam gole Join Date: Oct 2011 Posts: 3 Rep Power: 16	i tried but not succeded in creating this varible with formula....... please help

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Nusselt number calculation in Fluent	Sharadkumar Yeri	FLUENT	52	May 29, 2019 07:29
why does nusselt number never reaches a fixed number when i plot it?	Ali taba	Main CFD Forum	0	January 5, 2012 18:34
[blockMesh] BlockMeshmergePatchPairs	hjasak	OpenFOAM Meshing & Mesh Conversion	11	August 15, 2008 08:36
[Commercial meshers] Trimmed cell and embedded refinement mesh conversion issues	michele	OpenFOAM Meshing & Mesh Conversion	2	July 15, 2005 05:15
Nusselt Number of the order of 35000	chinmay	FLUENT	4	May 31, 2001 04:06

March 25, 2012, 07:28		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 18,011 Rep Power: 146	Define a variable in CFD-Post with the equation for Nussult number. Then you can use this variable as a normal results file variable -you can plot it, get min/max, integrate it, graph it against something etc etc

March 27, 2012, 11:55		#4
Studentdrak Member Join Date: Aug 2011 Posts: 53 Rep Power: 16	how did u try pritam? what is your formula?

March 27, 2012, 16:06		#5
lffabiani Member Luis Filipe Fabiani Join Date: Apr 2009 Posts: 43 Rep Power: 18	On CFD-POST first create an expression Example: sqrt(Velocity w^2) and name it ("nusselt", "my expression", or whatever) Then on variables, create a new variable (also name it as you wish) and point the "expression" field to the expression you just created.