Study on heat transfer characteristics of reservoir embedded loop heat pipe (Influence of condenser cooling method on heat transfer characteristics)

Abstract

Japan Aerospace Exploration Agency, JapanAs heat generation in satellites increases, securing sufficient radiator panel area is an important problem. Deployable radiators, whose radiator panels are deployed post-launch in space to increase the effective radiator panel area of the satellite, is becoming an important thermal control technology. A reservoir embedded loop heat pipe (RELHP) is applied to the deployable radiator for a thermal transport device. This paper presents the heat transport dynamic characteristics of a RELHP using a radiant cooling condenser and liquid forced convection cooling condenser by an experimental study. It was found that heat leak into the liquid line, flexible line, and reservoir increases the length of the sub-cooling region in the condenser. In the case of the radiant cooling condenser, the sub-cooling region length is shorter than that of a liquid forced convection cooling condenser. Furthermore, vapor temperature is mainly decided by the radiation capacity of the radiator panel, because liquid temperature returned into the evaporator rises with an increase in radiator panel temperature. In addition, time length from start-up until steady state is greater than the liquid forced convection cooling condenser case, because the radiator panel has a large heat capacity.