Numerical simulation of heat and mass transfer in a 3D model of a loop heat pipe evaporator

The article presents results of 3D numerical simulation of flow and conjugate heat and mass transfer in a model of the TacSat-4 satellite loop heat pipe evaporator. The mathematical model includes the Reynolds-averaged Navier-Stokes equations describing the flow in the liquid and vapor regions, Darcy's law for filtration modeling in the wicks and the energy equation with accurate coupling of connected sub-domains including effects of evaporation on interfaces between the porous and vapor regions. According to the simulation results, the evaporation localizes mainly at the vapor groove corners near the evaporator body. The vapor grooves operate under essentially different conditions, as a result, the flow rates differ by several times. Significant thickening of the evaporator body yields only weak reduction in a level of the grooves' flow rate non-uniformity.