[stenzer]

Hi guys,

I calculated the cooling of a plate by a turbulent forced convection analytically. Now I want to check my results with COMSOL 4.3 but I have some troubles, maybe someone would be so kind and help me.

My plate is 0.075 m long, to keep the plate at +4 °C i need a power of ~130 W. The cooling fluid is air and has a temperature of -30 °C with a "inflow" - velocity of 45 m/s.

I tried to model my plate in COMSOL with a rectangle ( 0.075 m x 0.005 m ), this plate is in the upper right corner of an "larger" rectangle. The inlet is on the left. The material of my plate is copper.

My first problem is how to fit the power, because for my analytic approach i have just a surface (~0.017 m^2) but no volume, which is necessary for a heat source with a unit of W/m^3. When I try to run the simulation with "Total Power" equal my required 130 W, the result is far away from my analytical one.

I'm thankful for any advice, I'm pretty new at COMSOL and an electrical engineer so I'm not really familiar with themal stuff ;-).

BR