Energy distribution and thermodynamic assessment of cavitating coolant flow in a micropump

As the vital energy management system for the satellite, the thermal control system transports the cooling temperature-sensitive medium via the micropump, where the mixed transportation involves hydraulic energy loss and heat dissipation. To achieve accurate predictions for the cavitating flow, the revised thermodynamic cavitation model was applied into the multiphase cavitating calculations. Based on this, a novel energy loss assessment method was introduced to qualify the heat dissipation, flow dissipation, flow transportation and entropy wall loss. Further, the detailed relationship between the loss sub-items including eight characteristic losses and thermodynamic cavitating characteristics was revealed. The results indicated that the thermodynamic effect reduces the dominated dissipation loss and wall loss, and further reduces the total loss. Turbulent kinetic energy production is the dominant factor of impeller and volute losses, accounting for 46–60 % of the total losses, and direct dissipation of the wall mainly influences the losses of the suction chamber, accounting for 32–45 % of the total losses. Lower cavitation number reduces most correlations of losses; thermodynamic effects barely affect correlation indices. Current study is the comprehensive description of flow and heat losses in the fluid machineries, which can provide guidance for the loss diagnosis in the multiphase flow.