N2O单组元微推力器性能分析及试验

Performance analysis and experimental research on nitrous oxide monopropellant micro-thruster

N2O单组元微推进是当前微推进领域的一个热点问题.在N2O催化分解热力计算的基础上开展了对N2O单组元微推力器比冲性能影响因素的分析,分析结果表明微推力器比冲与N2O分解效率及喷管扩张比有密切关系.所开展的亚牛级N2O单元微推力器催化分解试验结果表明所设计N2O单元推力器能在250℃初温条件下启动,初步验证了N2O单元微推力器的可行性;也揭示了推力室结构及床载大小对亚牛级N2O单元微推力器性能的影响,为进一步的结构及试验设计提供了参考.

Performance analysis for monopropellant micro-thruster using nitrous oxide （N2O） propellant was carried out based on the thermodynamic computation. Preliminary results show that decomposition rate of nitrous oxide and the expansion ratio of nozzle both have effects on the specific impulse of the thruster. Experiments of nitrous oxide catalytic decomposition at different initial catalyst bed temperature were conducted in testers of different structures. Self-sustaining decomposition reaction of nitrous oxide was observed at preheated temperature of 250 ℃. The performance of the sub-Newton micro-thruster was greatly affected by the combustion chamber structure and the loading factor of catalyst bed according to experimental results. Although the results are not conclusive because of the small initial test set, preliminary numbers demonstrate the feasibility of the N2O monopropellant micro-thruster.