Numerical study on thermohydraulic behavior in compensation chamber of a loop heat pipe with flat evaporator

Numerical simulations have been conducted extensively in the researches of loop heat pipe during recent years for capturing the precise mechanism. In this study, a three-dimensional computational fluid dynamic model of compensation chamber in pump-assisted loop heat pipe was developed for investigating the thermohydraulic mechanism systematically. In order to explain the temperature fluctuation inside compensation chamber while high heat leak was considered, numerical simulation was implemented by adopting the volume of fluid method. The characteristic of heat transfer was determined by the vapor distribution and heat flux variation. Simulation results indicated the existence of subcooled flow boiling inside compensation chamber. Additionally, bubbles mainly got formed on wick surface, and a flow structure transform was found due to the uneven vapor distribution and turbulence intensification. Decreasing in mass flowrate or increasing in heat leak led to an augmentation of vapor volume and nucleation site density. However, environmental convection showed slight influence on heat and mass transfer.