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921.
Inertial Navigation System/Celestial Navigation System(INS/CNS) integration, especially for the tightly-coupled mode, provides a promising autonomous tactics for Hypersonic Vehicle(HV) in military demands. However, INS/CNS integration is a challenging research task due to its special characteristics such as strong nonlinearity, non-additive noise and dynamic complexity.This paper presents a novel nonlinear filtering method for INS/CNS integration by adopting the emerging Cubature Kalman Filter(C... 相似文献
922.
923.
Aimed at complex distributed no-fly zones avoidance problems, a novel adaptive lateral reentry guidance algorithm is proposed. Firstly, by introducing the improved attractive and repulsive potential fields, an improved artificial potential field method is developed. Combined with the proposed judgment criterion for whether a no-fly zone has been avoided, the proposed improved artificial potential field method effectively solves the reference heading angle determination problem under the constrai... 相似文献
924.
《中国航空学报》2023,36(2):29-40
Due to the pneumatic heating and combustion effect, the scramjet engine of hypersonic vehicle faces high temperature challenge. It is necessary to comprehensively consider its thermal management and power generation together. A new Power and Thermal Management System (PTMS) combined with Supercritical Carbon Dioxide (SCO2) closed Brayton cycle and fuel vapor turbine is proposed and discussed in this paper. The new PTMS can meet the cooling requirement of hypersonic vehicle at Mach number 6–7, and avoid the coking and scrapping in the scramjet cooling channels. Compared with the PTMS only based on fuel vapor turbine, the new PTMS utilizes the waste heat of scramjet to generate more electricity. In addition, it can reduce the use of fuel sink for cooling, and the additional weight penalty can be compensated for long endurance hypersonic flight. 相似文献
925.
Pressure-gain combustion has gained attention for airbreathing ramjet engine applications owing to its better thermodynamic efficiency and fuel consumption rate. In contrast with traditional detonation induced by a single wedge, the present study considers oblique shock interactions attached to double wedges in a hypersonic combustible flow. The temperature/pressure increases sharply across the interaction zone that initiates an exothermic reaction, finally resulting in an Oblique Detonation Wav... 相似文献