Configuration Design And Numerical Simulation Of Cryogenic Capillary Pumped Loop (CCPL)

This paper describes the development of an advanced cryogenic integration device-the cryogenic capillary pumped loop (CCPL), a miniaturized two-phase fluid circulator for thermally linking cryogenic cooling sources to remote cryogenic components. A CCPL utilizes the latent heat of vaporization of a working fluid to transfer heat and the surface tension forces forms in fine-pore wicks to circulate the working fluid. Design procedure for different CCPL configurations and its heat transfer limitations are discussed. Especially the design procedure of liquid cooled shield (LCS) is introduced. Furthermore, a CCPL unit is designed; the unit utilizes nitrogen as the working fluid and operates between 80 and 90K.The CCPL numerical model is established by using the nodal or lumped parameter method. In the three different operation cases: start-up from a supercritical state, heat load increase and cold reservoir set point temperature change, the variation curves of temperature, pressure and mass flux varying with time are given. The results of simulations accord with the principles of CCPL and correctly reflect the dynamic characters of CCPL. It is concluded that the model is reasonable and the computed results are satisfying.In order to show the dynamic process of CCPL, this paper also designs the program interface of CCPL design software using VB6.0. The 3D model of CCPL is plotted using 3DS Max. Using particle system, the 3D demo animation system is developed; the generation and flow process of vapor in CCPL are displayed.