3D-model for heat and mass transfer simulation in flat evaporator of copper-water loop heat pipe

This paper presents a three-dimension mathematical model of a flat evaporator of a loop heat pipe which takes into account the peculiarities of the evaporator configuration and the specific character of a one-side heat load supply. All the main structural elements of the evaporator, such as its body, wick, vapor-removal grooves, barrier layer and compensation chamber, are included in the model. The intensity of heat-exchange processes during evaporation in the active zone is determined by local drops between the temperature at the wick surface and the vapor temperature. The effects of drying the wick in the evaporation zone are also taken into account. The problem was solved by a numerical method. The results of calculations are presented for a copper evaporator and water as a working fluid in the heat load range from 20 to 1100 W. A comparative analysis of calculated and experimental data has been made.

► A three-dimensional thermal model of a flat evaporator of a loop heat pipe was developed.
► Numerical results for a copper evaporator and water as a working fluid were obtained.
► Heat-transfer processes were studied in the heat load range from 20 to 1100 W.
► The results showed a qualitative agreement with the experimental data.
► Crisis modes connected with the wick drying were simulated.