I am trying to determine the base temperature of this simple heat sink using Solidworks Flow Simulation. I am using the conditions specified in a heat transfer question (aluminum heat sink, parallel water flow of 3m/s, ambient temperature of 17 degrees C, power dissipated from chips to heat sink = 1800W). I know this is very easy to calculate by hand but I am doing this to practice using Flow Simulation. The base temperature according to my calculated answer and the solution in the textbook should be about 46 degrees C but when I use Flow Simulation, I get a temperature of around 36.5 degrees C. In addition, the temperature of the flow trajectories does not change as they pass through the fins of the heat sink and I don’t think that this should be the case (see below).
I would really appreciate any suggestions on what I should check/change to make my simulation more accurate. My mesh in the 3D analysis is pretty bad but I wanted to reduce the run time of the simulation. A 2D analysis with a better mesh gives me a very different (even worse) temperature distribution (see below).