Hi everyone, I've a problem with my CPU cooler simulation which I can not solve. Cooler consists of heatsink with heatpipes and rotating 120mm fan. Main goals which I want to obtain are: max cpu temp, max velocity and volumetric flow rate of fan. As the simulation finished, I noticed that the volumetric flow of fan is very low - about 20 CFM (cubic feet/min) for 120mm fan@1600rpm, but the temperatures seemed to be ok. To investigate it, I started the simulation again but with the lone fan only, with all parameters being the same (angular velocity, mesh etc) and the result was about 40 CFM (acceptable for this kind of fan), max velocity was the same as in the previous simulation. It seems that the flow rate of fan changes after attaching heatsink, but it should not. So the question is, why?