DESIGN OF A THERMAL CONTROL SYSTEM WITH A TWO-PHASE CIRCUIT FOR A SPACECRAFT WITH A CAPACITY OF UP TO 15 kW
This paper presents a methodological approach to the design of a spacecraft thermal control system with coolant pumping with a cooling capacity of up to 15 kW. Two variants of constructions are considered. A thermal and mass-energy analysis of the thermal control system for an automatic spacecraft with active coolant pumping using the heat of the phase transition is carried out. Structurally, the thermal control system consists of a two-phase circuit and axial heat pipes. Sequential laying of a circuit for heat collection is impractical, as it leads to excessively large diameters of steam paths. It is required to consider either a scheme with parallel laying of steam mains, or a variant with a central two-phase bus and autonomous circuits for heat collection / removal. The proposed layout of the thermal control system with two-phase circuit and active pumping of the coolant with a capacity of up to 15 kW provides for the necessary area of the radiation panels. Two variants are considered: with a central heat bus and with a parallel connection of the evaporation line. The results of the analysis show a mass acceptance of the two-phase thermal control system with a central reserved bus. The reliability parameter for the first option is also higher, since it has full redundancy of the central heat bus. In the second option, it is difficult to reserve the contour. The advantage of the second option is a lower thermal resistance during heat transfer from the equipment, therefore, large estimated reserves for the temperature of the equipment seats.