Modeling for heat and mass transfer with phase change in porous wick of CPL evaporator

Abstract

A mathematic model is developed to describe heat and mass transfer with phase change in the porous wick of evaporator of capillary pumped loop (CPL). This model with six field variables, including temperature, liquid content, pressure, liquid velocity, vapor velocity and phase-change rate, is closed mathematically with additional pressure relationships introduced. The present model is suitable to the numerical computation, as the established equations become comparatively easy to solve, which is applied to CPL evaporator. The numerical results are obtained and the parameter effects on evaporator are discussed. The study demonstrates that instead of an evaporative interface, there exists an unsaturated two-phase zone between the vapor-saturated zone and the liquid-saturated zone in the wick of CPL evaporator.