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Evaluation of Nusselt Number (Nu) for Natural Convection

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Hi everyone,

can someone tell me how to evaluate Nusselt Number Nu, in comsol 4.0a. (there are lot of parameter available in post processing results menus but Nu is not there).


Thanks.

2 Replies Last Post 28 févr. 2012, 06:12 UTC−5
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 6 janv. 2012, 06:17 UTC−5
Hi

use the formula Nu = h*L/k but you still have the unknown about the "scale length" "L" to use and often too for "h".
You have the same issue with Re, that is why the Reynolds number given in COMSOL is the "Cell Reynolds number" based on the COMSOL internal length variable "h" : the mesh averaged dimension (not be be confused with my flux "h" above

--
Good luck
Ivar
Hi use the formula Nu = h*L/k but you still have the unknown about the "scale length" "L" to use and often too for "h". You have the same issue with Re, that is why the Reynolds number given in COMSOL is the "Cell Reynolds number" based on the COMSOL internal length variable "h" : the mesh averaged dimension (not be be confused with my flux "h" above -- Good luck Ivar

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Posted: 1 decade ago 28 févr. 2012, 06:12 UTC−5
Thanks alot sir

Safeer
Thanks alot sir Safeer

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