Considerations to Reduce Neutron Induced Heating of the Beryllium Reflector Drums of a Thermionic Space Craft Reactor during Thrust Phase
A neutronic and thermo-hydrodynamic analysis is performed for a fast, uranium carbide (UC) fueled in-core thermionic space craft nuclear reactor, designed both for electricity generation and nuclear thermal propulsion. Calculations with natural B4C segments imbedded in rotating beryllium control drums in the radial reflector have shown that reflector drums with 100 ％ natural B4C in form of strips (drum diameter = 13.5 cm, strip width = 5 mm) at the outer periphery of the radial reflector of 16 cm thickness would make possible reactivity changes of 兇keff,max = 10.7 ％ without a significant distortion of the heat generation during all phases of the space mission. A reduction of the B4C in the strips to 20 and 10 ％ would still allow a reactivity change of 兇keff,max = 8.4 and 7.7 ％, respectively, amply sufficient for an effective control of a fast reactor during all phases of the space mission. By a nuclear thermal thrust around F = 5000 N and a specific impulse of 670 sec-1 at an hydrogen exit temperature around 1900 K, the maximum temperature in the drums rises to 1023 oK, with 100 ％ natural B4C content in the strips, far below the melting point of beryllium. The maximum drum temperature is depressed to 663 and 519 K, with 20 and 10 ％ natural B4C content in the strips, respectively.
Spacecraft thermionic reactors reflector heating power propulsion
Sumer Sahin
Atlim University, Faculty of Engineering, 06836 Incek Golbast, Ankara, TURKIYE
国际会议
4th International Symposium on Heat Transfer and Energy Conservation(第四届传热与节能国际研讨会 ISHTEC2012)
广州
英文
1-5
2012-01-06（万方平台首次上网日期，不代表论文的发表时间）