Fluent natural convection
Fluent natural convection
(OP)
Hi,
I'm dealing with an heat sink in an air enclosure. Attached to the heat sink there's a chip with an internal heat source.
I'm setting the Fluent model with the "laminar" behaviour for really low Reynolds number.
My target is understand how much is the influence of natural convection on the heat sink final temperature.
So, I'm conducting a steady state simulation with the Boussinesq Model and laminar behaviour.
It's correct?
I made the same simuation in Ansys steasy state thermal package indicating an average convection coefficient (20 W/m^2k alluminium - air). The results are really different from fluent simulation output. Why??
Thanks so much!!
I'm dealing with an heat sink in an air enclosure. Attached to the heat sink there's a chip with an internal heat source.
I'm setting the Fluent model with the "laminar" behaviour for really low Reynolds number.
My target is understand how much is the influence of natural convection on the heat sink final temperature.
So, I'm conducting a steady state simulation with the Boussinesq Model and laminar behaviour.
It's correct?
I made the same simuation in Ansys steasy state thermal package indicating an average convection coefficient (20 W/m^2k alluminium - air). The results are really different from fluent simulation output. Why??
Thanks so much!!





RE: Fluent natural convection
addition to natural convection?
You can output heat transfer coefficient in CFD post, probably also in Fluent.
By the way have you considered radiation in your models? Many times in natural convection its influence
cannot be neglected.
If you can post some pictures of the setup, it would help.
RE: Fluent natural convection
TTFN (ta ta for now)
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RE: Fluent natural convection
The ambient temperature is 26 °C and i want understand how much is the effect of a natural air convectioni for the Heat sink temperature distribution.
Clearly this effect is not present in the same simulation made in ansys workbench steady state thermal.
RE: Fluent natural convection
I shoud use the laminar model , right?
Thanks again
RE: Fluent natural convection
(regarding the original post).
Those numbers should tell you whether the flow is laminar or turbulent.
Also mesh near the walls can affect the results. Meshing should be done taken
into consideration the turbulence model you are using.
RE: Fluent natural convection
RE: Fluent natural convection
TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm
RE: Fluent natural convection
Thanks again.