空间堆热管输热能力分析

为保证空间堆的传热安全,空间堆热管必须工作在各种传热极限以下,并能满足避免单点失效的安全要求。本文建立了空间堆热管黏性极限、声速极限、携带极限、沸腾极限和毛细极限5种传热极限计算方法,并改进了毛细极限计算模型。利用建立的方法计算了分段式热电偶转换的热管冷却空间堆电源系统堆芯锂热管、辐射散热器钾热管和碱金属热电转换的空间堆电源系统堆芯钠热管的传热极限。结果表明,空间堆用锂热管和钠热管的毛细极限分别为25.21kW和14.69kW,钾热管的声速极限为7.88kW,其传热设计冗余量分别大于19.4%、23.6%和43.2%。空间堆堆芯热管在正常运行时限制其热量输出的传热极限为毛细极限,而限制散热器钾热管正常运行时热量输出的传热极限为声速极限。

Heat Transfer Capability Analysis of Heat Pipe for Space Reactor

To insure the safety of space reactor power system with no single point failures, the reactor heat pipes must work below its heat transfer limits, thus when some pipes fail, the reactor could still be adequately cooled by neighbor heat pipes. Methods to analyze the reactor heat pipe’s heat transfer limits were presented, and that for the prevailing capillary limit analysis was improved. The calculation was made on the lithium heat pipe in core of heat pipes segmented thermoelectric module converter (HP-STMC) space reactor power system (SRPS), potassium heat pipe as radiator of HP-STMC-SRPS, and sodium heat pipe in core of scalable AMTEC integrated reactor space power system (SAIRS). It is shown that the prevailing capillary limits of the reactor lithium heat pipe and sodium heat pipe is 25.21 kW and 14.69 kW, providing a design margin >19.4% and >23.6%, respectively. The sonic limit of the reactor radiator potassium heat pipe is 7.88 kW, providing a design margin >43.2%. As the result of calculation, it is concluded that the main heat transfer limit of HP-STMC SRPS lithium heat pipe and SARIS sodium heat pipe is prevailing capillary limit, but the sonic limit for HP-STMC SRPS radiator potassium heat pipe.