Thermal equiblium between conduction and convetion

nima103

Hi every one,

 

I am trying to simulate a convection and conduction model and compare it with analytic results. I have a cube with K value of 100 as it can be seen in the attachment, with upper surface temperature of 40. The lower surface is exposed to free convection with amb. temp of 20 and H value of 40. The thinkness if cube is 0.35m.

 

Analytical calculation of problem would yield lower surface temp. of 37.3 while simulation results always gets very close to ambient temperature. can anyone explain why there is a difference ?

 

T1 = 40

K = 100

H = 40

Tamb = 20

L = 0.35

T2 = ?

 

k.(T1-T2)/L = H(T2 - Tamb)

T2 = 37.3

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Rahul Rajan_21763

Can you share us the .fem file?

nima103

Hi Rahul,

 

yes sure

Unable to find an attachment - read this blog

nima103

Altair Forum User said:

Can you share us the .fem file?

 

I found out Rahul, the simulation is correct, I have a mistake in calculation. I shoud have used 35 as thikness instead of 0.35 

Rahul Rajan_21763

Thanks for the update.