Wick having liquid superheat tolerance and being resistant to back-conduction, evaporator employing a liquid superheat tolerant wick, and loop heat pipe incorporating same

摘要

A capillary wick for use in capillary evaporators has properties that prevent nucleation inside the body of the wick, resulting in suppression of back-conduction of heat from vapor channels to the liquid reservoir. Use of a central liquid flow channel in the wick is eliminated, and pore size in the wick is chosen to maximize available pressure for fluid pumping, while preventing nucleation in the wick body. The wick is embodied with different geometries, including cylindrical and flat. A flat capillary evaporator has substantially planar heat input surfaces for convenient mating to planar heat sources. The flat capillary evaporator is capable of being used with working fluids having high vapor pressures (i.e., greater that 10 psia). To contain the pressure of the vaporized working fluid, the opposed planar plates of the evaporator are brazed or sintered to opposing sides of a metal wick. Additionally, a terrestrial loop heat pipe and a loop heat pipe having overall flat geometry are disclosed.