Design And Experimental Research Of Capillary Pumped Loop

The Capillary Pumped Loop is such a system, of which the driven potential depends on the phase change of the working fluid and the capillary force. With high efficiency, high dependability, and energy saving, as a two-phase thermal-control system, it is applied in many fields such as controlling heat transfer on spacecrafts, cooling electronic devices with high power density. The system drives the working-media circulation by the capillary pressure across the surface tension formed at the liquid-vapor interface, transferring the great heat loads with low temperature difference by phase change.However, many investigations about the system indicate that there are problems that plague the application of it, such as being difficult to start-up and being unsteady when pressure oscillated during operation. Therefore, how to restrain the hydrodynamic oscillation and improve the start-up ability is the crucial issue on the system research. Many researchers are now investigating these problems.This thesis introduced the operation principles and characteristics of the Capillary Pumped Loop system, and gave some comments on the systems that had already been made. Based on their experience and what we had learned, we designed a new type CPL with flat evaporator. In order to better understand and analyze its operation theory and working performance, we had done lots of experiments on the new type system about the start-up and unsteady operation capabilities. The results indicated that the new type system had great start-up ability and steady working performance.In order to accord with the trend of electronic devices having higher and higher power density, we designed a new type miniature LHP system with disk evaporator, hoping to resolve the heat dissipation problems when the power density is above 10W/cm2. The structure of the disk evaporator was introduced in this article. The simulations for strength analysis were taken with 3-D model created using ANSYS, the results indicated that both the strain and the stress were under control. Also the simulations for transient thermal analysis before the evaporator start-up were taken; the results show the temperature distributions in the evaporator at different time. The studies were meaningful and helpful for the experimental research in the future.