Development of Two-Phase Fluid Loop Systems for Future Space Platforms

Since 1985 NASDA has made studies on advanced thermal management systems, especially on two-phase fluid loops, with a view to applying to temperature control and heat rejection of future space platforms of tens of kW class. Our research on pump-driven two-phase fluid loop technology is in a new stage where we have completed the design and fabrication of a development model. This paper describes the loop system design and gives details of components, which are three kinds of cold plates (grooved double-pipe type, grooved multi-channel type, tube and plate-heat-pipe type), two kinds of volumetric pumps (trochoid gear type, scroll type) and an accumulator of vapor pressure driven type. This paper, then, gives a brief description of an X-ray void meter which we have prepared for measurements of void fractions and for graphical observations of various flow patterns in the cold plates.