空间核电推进系统比质量优化建模及其木星探测应用分析

空间核电推进(Nuclear Electric Propulsion,NEP)系统是一种将核热能转换成电能,并驱动大功率电推力器而产生推力的革命性空间推进技术。和传统推进技术相比,NEP具有高比冲、大功率、长寿命等技术优势,非常适合未来大规模深空探测任务。基于NEP系统组成和小推力轨道理论,建立了以有效载荷为目标的NEP系统比质量优化模型。该模型能够解析NEP航天器的轨道运行时间、比质量、功率与有效载荷比的复杂耦合关系,为任务优化提供了计算依据。最后,利用该模型对NEP系统完成NASA "Juno号"航天任务进行了技术指标评估分析。计算表明,当NEP系统比质量达到4.8 kg/kWe时,其能将"Juno号"航天任务的地木转移时间由2 266 d缩短至665 d,有效载荷由160 kg提高到1 179 kg,极大地提高了航天器的探测能力,为任务方案的可行性论证和后续设计提供参考。

Specific Mass Optimization Modeling of Space Nuclear Electric Propulsion System for Jupiter Exploration Mission

The space nuclear electric propulsion (NEP) system is a revolutionary space propulsion technology that converts nuclear heat energy into electrical energy and drives high-power electric thrusters to generate thrust. Compared with traditional propulsion technology, NEP has the advantages of high specific impulse, high power and long life, which is very suitable for large-scale deep space exploration missions in the future. In this paper, the specific mass model of high power NEP system is established based on NEP system composition and the theory of small thrust orbit to obtain the maximum payload ratio. The complex coupling relation of orbit time, specific mass, power and payload ratio of NEP spacecraft can be decoupled by this model, which provides a computational basis for task optimization. The model was used to evaluate the technical specifications of the NEP system to complete the NASA Juno space mission. The calculation shows that when the specific mass of the NEP system reaches 4.8kg/kWe, it can the ground transfer time of the Juno space mission from 2266 days to 665 days, and the payload from 160kg to 1179kg, which greatly improves the spacecraft''s detection capability and providing a useful reference for subsequent design.