Steady-state modelling of dual-evaporator loop heat pipe

Abstract

To promote the thermal management of loop heat pipe in aerospace and electronics, a steady-state heat transfer model of the asymmetric dual-evaporator loop heat pipe (DE-LHP) is established, in which the mass flow distribution at the junction of the liquid line is modified. The control of operating temperature between two compensation chambers (CCs), heat sharing characteristics and influence of heat sink and ambient temperature on operating temperature are analyzed. The control of operating temperature is influenced by the CCs position and heat load distribution between two evaporators. Two domination zones, namely the position domination zone and heat load distribution domination zone, are observed when the heat load of the distal evaporator is larger than that of the proximal evaporator. A formula for determining the influencing range of the position domination zone is also proposed. The operating temperature reaches the minimum when the heat loads applied to the two evaporators are equal. The ambient temperature influences the operating temperature at low system heat load while the heat sink temperature prevails at high heat load. The heat sharing is affected by the total heat load and the loop pressure distribution, and proportional to the flow distribution at the junction of vapor line.