Infeasible temperature rise with CHT v2.0

In my project I simulate passive (convection-only) heatsink and CPU. I provide 30 W power source to the CPU and surprisingly I get about 500K temperature rise of the heatsink in 15 seconds. This is at least 10x more rise than is expected even in the absence of any cooling: given aluminum specific heat(~900 J/kg /K), the heatsink weight (~0.05kg) and amount of energy provided (30 W x 15 sec), I would expect the rise be of order of 10K. What is wrong?

Hello vfurman,
thanks for reaching out to us in the forum,
from what I can see is that the air region is pretty small around your body.
Can you try a run where the air volume is roughly 5 times the length of the body in that direction?

This helps to exclude reduce the effects of the wind tunnel side walls.

Best regards Sebastian

Thanks for the reply, Sebastian!
I think my confusion is more at the conceptual level. Can you tell if CHT v2.0 is a transient simulation or a steady-state simulation? The CHT v1 gave an option to choose, but the option is not present in v2.

the CHT v2.0 currently only supports a steady-state analysis.
But for your case, you could use the convective heat analysis to analyze transient flow effects.

Best regards Sebastian

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