I am using the Simscape Fluids fixed displacement pump, with a thermal liquid. I looked through the documentation and could not find any explanation of how mechanical and volumetric efficiencies affect the fluid temperature. I am using "Input Efficiencies" block choice. When I reduce mechanical efficiency, the temperature of the outlet liquid increases, but not by as much as I would expect it to if 100% of the friction torque were added to the fluid. Is some of it assumed to be dissipated to the air? Similarly, when I reduce volumetric efficiency, the temperature increases, is this due to a fluid shearing effect? Are these equations documented anywhere?
I am working on a model where I need to account for all energy streams, so if some of the heat is assumed to go somewhere other than the thermal liquid, I need to account for it separately.