Performance Analysis of Potassium Heat Pipes Radiator for HP‐STMCs Space Reactor Power System Available to Purchase

A detailed design and performance results of C‐C finned, and armored potassium heat pipes radiator for a 110 kW_e Heat Pipes‐Segmented Thermoelectric Module Converters (HP‐STMCs) Space Reactor Power system (SRPS) are presented. The radiator consists of two sections; each serves an equal number of STMCs and has 162 longitudinal potassium heat pipes with 0.508 mm thick C‐C fins. The width of the C‐C fins at the minor diameter of the radiator is almost zero, but increases with distance along the radiator to reach 3.7 cm at the radiator’s major diameter. The radiator’s heat pipes (OD = 2.42 cm in front and 3.03 cm in rear) have thin titanium (0.0762 mm thick) liners and wicks (0.20 mm thick with an effective pore radius of 12–16 μm) and a 1.016 mm thick C‐C wall. The wick is separated from the titanium liner by a 0.4 mm annulus filled with liquid potassium to increase the capillary limit. The outer surfaces of the heat pipes in the front and rear sections of the radiator are protected with a C‐C armor that is 2.17 mm and 1.70 mm thick, respectively. The inside surface of the heat pipes in the front radiator is thermally insulated while the C‐C finned condensers of the rear heat pipes are exposed, radiating into space through the rear opening of the radiator cavity. The heat pipes in both the front and the rear radiators have a 1.5 m long evaporator section and each dissipates 4.47 kW while operating at 43.6% of the prevailing sonic limit. The front and rear radiator sections are 5.29 m and 2.61 m long with outer surface area and mass of 47.1 m² and 314.3 kg, and 39.9 m² and 243.2 kg, respectively. The total radiator is 7.63 m long and has minor and major diameters of 1.48 m and 5.57 m, respectively, and a total surface area of 87 m²; however, the effective radiator area, after accounting for heat rejection through the rear of the radiator cavity, is 98.8 m². The radiator’s total mass including the C‐C armor is 557.5 kg and the specific area and specific mass are 6.41 kg/m² and 5.07 kg/kW_e, respectively.