Two-phase Thermal Regulation System of a Manned Spacecraft

摘要

Because of increasing interest of manned space exploration, continuous development of space technologiesrnand space vehicles is needed. The most important aspect that should be considered at first is development ofrnperspective life support and cooling systems that are essential on every spacecraft.rnModern space cooling systems can be divided on two rather common: single-circuit and double-circuit. Thernsingle-circuit system consists of only one hydraulic pipeline, that goes straight from inner space of the spacerncraft to the outer space, so this type should be used commonly for unmanned space crafts, because itsrnunsafety. Safer modern cooling system consists of two hydraulic circuits with pumps: internal and external.rnThey are connected by a heat exchanger. So the internal circuit collects extra heat using heat exchangers andrntransmits it into the external hydraulic circuit by the heat exchanger. The external circuit throws this heat tornthe outer space using radiation heat exchanger.rnAs known from Stefan-Boltzmann equation it is possible to decrease area of radiator if its temperature couldrnbe increased. It is evident, that if temperature of coolant in the space radiator could be increased, it isrnpossible to improve mass-size characteristics of the radiator, the cooling system and the space vehicle inrncommon.rnCommon cooling system uses external one-phase hydraulic circuit. A two-phase hydraulic system, thatrnworks as a refrigeration machine could be more effective. In such system the heat exchanger and radiatorrnfulfill the role of evaporator and condenser of the refrigeration machine respectively. It is possible to increasernconsiderably the temperature on a surface of the radiator on account of a compressor in the circuit thatrncompresses the refrigerant after evaporator. In comparison with common system, we can reach a growth ofrnthe heat flow from the radiator in 3,0 times approximately, which will cause the decreasing of radiator’s area.