Design and Investigation of a Capillary Pumped Loop for Advanced Thermal Control Systems of Space Vehicles

The paper is devoted to discussing the problems of serviceability of capillary pumped loops (CPL) in startup and stationary modes of operation. It gives the results of experimental investigation of a CPL with a length of the transportation zone of about 5 m and high-pressure capillary pumps creating a head up to 40 kPa on ammonia and 20 kPa on freon-152A, which have been tested as working fluids. On the basis of the experimental data and analysis of the CPL operating cycle the paper gives the determination of serviceability conditions connected with the required degree of subcooling of the working fluid that is supplied into capillary pumps.