SimScale CAE Forum

Conduction,Convection,Radiation analysis


#1

I wanna know if there is any way to apply the 3 modes of heat transfer at the same time for design consideration as my case is simulating a heat sink with a led chip as a heat source with natura convection boundary conditions and the heat sink is anodized aluminum with emissivity =0.85 and as known in such natural convection analysis the radiation takes place with at least 30% of heat dissipation, so any hints? (i used the heat transfer mode and the CHT also but still with a a significant error) the link: https://www.simscale.com/projects/GENDY/hs_cn/


#2

Hey Gendy!

From the meshing log, towards the end, you can see some issues: “Detected 14 valid interfaces. 20 interfaces failed to be resolved with the applied mesh fineness.”

In the meshing log, you can also find a list of interfaces that were not resolved due to the mesh being too coarse. This is most likely the cause for the poor results.
Basically you should either use a moderate/fine mesh or set local refinements to the heat sink and its surroundings.

/Ric


#3

Thanks for revision i noticed that but didn’t give it atention or make refinements just bcz wanted to c how in general the solution would be, also wanted to make who c the topic to be aware of what i’m going to execute but i would use a more detailed model with a more deatailed setup once i getknow what the perfect mode for my case(as u can see i have already a cartesian boxes for refinements but just that is the very primary model test)


#4

Further inquiry is that number of contacts r logic as they supposed to be just two solid parts in contact(the heat source and the heat sink)?


#5

Interfaces account for both solid/solid and solid/fluid. In fact, for your geometry, the majority of interfaces are solid/fluid.


#6

Thanks, any idea of what be the best mode for best fesult or how i can include the 3 main HT modes in one simulation?


#7

Sadly conjugate heat transfer does not model radiation. I’d still give conjugate heat transfer a try, following this tutorial.


#8

thanks for ur concern have a good day


#9

Hi @GENDY, radiation has only recently been released and as a first step was released to convective HT only. As we progress it will become available in the conjugate heat transfer type also.

Best,
Darren