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81.
为满足微小卫星对推进系统小质量、小体积、低功耗、低成本的要求,设计了一种微型双稳态电磁阀。采用尽量缩短阀门衔铁运动行程、合理设定衔铁两端间隙、用两个线圈实现开/关控制等措施,以及新的工艺和制造技术.实现了阀门的轻质、低功耗、快响应和长寿命。试验和实际应用结果表明,该阀门完全可满足微小卫星的应用要求。 相似文献
82.
83.
王江%马国富%郑剑%刘小坤 《宇航材料工艺》2002,32(6):32-35
介绍了空间站各系统密封材料的使用环境及对材料的性能要求;对空间站中气动系统、推进系统和液压系统使用的密封材料进行了配方研制;重点对气动系统密封材料的环境适应性与空间卫生性给出了评估。结果表明,材料满足航天器使用环境的需要。 相似文献
84.
A direct fusion drive for rocket propulsion 总被引:1,自引:0,他引:1
Yosef S. Razin Gary Pajer Mary Breton Eric Ham Joseph Mueller Michael Paluszek Alan H. Glasser Samuel A. Cohen 《Acta Astronautica》2014
The Direct Fusion Drive (DFD), a compact, anuetronic fusion engine, will enable more challenging exploration missions in the solar system. The engine proposed here uses a deuterium–helium-3 reaction to produce fusion energy by employing a novel field-reversed configuration (FRC) for magnetic confinement. The FRC has a simple linear solenoid coil geometry yet generates higher plasma pressure, hence higher fusion power density, for a given magnetic field strength than other magnetic-confinement plasma devices. Waste heat generated from the plasma?s Bremsstrahlung and synchrotron radiation is recycled to maintain the fusion temperature. The charged reaction products, augmented by additional propellant, are exhausted through a magnetic nozzle. A 1 MW DFD is presented in the context of a mission to deploy the James Webb Space Telescope (6200 kg) from GPS orbit to a Sun–Earth L2 halo orbit in 37 days using just 353 kg of propellant and about half a kilogram of 3He. The engine is designed to produce 40 N of thrust with an exhaust velocity of 56.5 km/s and has a specific power of 0.18 kW/kg. 相似文献
85.
林来兴 《中国空间科学技术》1988,(4)
本文讨论空间站控制各种类型的推进系统。研究结论是推进剂消耗量是一个重要成本因素。电推进系统具有比化学推进器最少高一个数量级的比冲,所以采用电推进系统可以大量减少推进剂质量。电推进系统适用于比较大的总冲量的任务,诸如阻力补偿和轨道转移。 相似文献
86.
87.
《中国航空学报》2023,36(5):223-238
CubeSats have attracted more research interest recently due to their lower cost and shorter production time. A promising technology for CubeSat application is atmosphere-breathing electric propulsion, which can capture the atmospheric particles as propulsion propellant to maintain long-term mission at very low Earth orbit. This paper designs an atmosphere-breathing electric propulsion system for a 3 U CubeSat, which consists of an intake device and an electric thruster based on the inductively coupled plasma. The capture performance of intake device is optimized considering both particles capture efficiency and compression ratio. The plasma source is also analyzed by experiment and simulation. Then, the thrust performance is also estimated when taking into account the intake performance. The results show that it is feasible to use atmosphere-breathing electric propulsion technology for CubeSats to compensate for aerodynamic drag at lower Earth orbit. 相似文献
88.
《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2020,65(10):2290-2302
The HP3 instrument measures the thermal flux through the Martian crust using a penetration probe. Launched on the InSight mission in 2018, HP3 was deployed for penetration activities in the beginning of 2019. During initial operation, the instrument is vulnerable to slip, due to a combination of low system mass (3.3 kg on Earth), shocks delivered by the penetration probe’s action, and the possibility of an inclined attitude on the surface. An uncontrolled position change of the instrument on the surface can reduce the scientific output and even lead to a loss of the experiment if the probe’s supporting structure moves laterally. Naturally, the design of the feet has major impact on the total amount of slippage. A new design for the feet with a high slippage resistance capability at a low level of complexity and mass was developed for this instrument’s supporting structure. The design provides sufficient slippage resistance while fulfilling the challenging set of requirements for a Mars surface mission. The design was verified by test campaigns which emulate launch environments and operational behavior on Mars. This paper gives a detailed overview of the HP3 instrument itself, the relevant requirements, the complex different test campaigns and the final flight design. 相似文献
89.
Sensitivity analyses of satellite propulsion components with their thermal modelling 总被引:1,自引:0,他引:1
Cho Young Han Jae Ho You Kyun Ho Lee Hui Kyung Kim Sung Nam Lee 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
Performing the sensitivity analyses of the contact conduction and the position of thermostat on the basis of the thermal model established, the study of thermal design is accomplished for the preparation of possible mechanical interface change of the satellite propulsion system depending on the satellite system design. A relatively simple thermal model is taken into consideration for the convenience of the analysis. A variety of the spacecraft bus voltages and the contact resistances are examined as well as the position of thermostat on propulsion components. As a consequence, even though the mechanical interface condition is changed on the same module, the successful thermal design could be achieved if we design the heater to have sufficiently large power with reference to the heritage value of contact resistance. Besides the reasonable performance on the thermal control is assured with the thermostat location errors, if the uncertainty in the position of thermostat is not quite large when assembling tank module. 相似文献
90.
基于复合推进系统动态模型-状态变量模型的航空发动机直接推力预测控制 总被引:2,自引:1,他引:1
直接推力控制可以有效改善推力控制的品质,针对航空发动机直接推力控制问题,进行了模型预测控制(Model Predictive Control, MPC)研究。为了提升航空发动机推力控制的精度,提出了基于复合推进系统动态模型-状态变量模型(Compact Propulsion System Dynamic Model-State Variable Model-State Variable Model, CPSDM-SVM)的航空发动机直接推力预测控制方法。CPSDM实时估计出不可测参数(推力、喘振裕度等)的基准值,SVM则根据未来输入实时预测发动机未来响应。由于CPSDM将发动机分为进气道、核心机、喷管、喘振裕度、推力等进行建模,在兼顾精度的同时,提高机载模型的实时性。CPSDM-SVM作为MPC算法中的预测模型,具有较高的精度和实时性。仿真结果表明,在与基于分段线化模型的传统模型预测控制方法实时性基本相同的情况下,所提出方法控制效果有明显的提升,调节时间减小了1.17s。所提出方法稳态控制精度为0.08%,传统方法稳态精度为2.58%。因此,所提出方法在保证实时性的条件下,提升了控制精度和控制效果。 相似文献