Combined with a UAV of the shape like Global Hawk, a new inlet is advanced to obtain high performance in both Radar Cross Section(RCS) and aerodynamic drag. Efforts are made to achieve this goal such as adopting a top...Combined with a UAV of the shape like Global Hawk, a new inlet is advanced to obtain high performance in both Radar Cross Section(RCS) and aerodynamic drag. Efforts are made to achieve this goal such as adopting a top-mounted inlet configuration, utilizing the diverterless technique and putting forward a new shape of entrance. A design method is brought forward and verified by wind tunnel tests. Results indicate: (1) Despite the negative effect of the front fuselage and the absence of the conventional boundary diverter, the performance of the top-mounted diverterless inlet advanced here(Ma:0.50-0.70, α:-4°-6°,σ>0.975) is equivalent to that of conventional S shaped inlet with diverter; (2) The integration of the inlet with the fuselage is realized by the utilization of a special inlet section and the diverterless technique, which disposes the whole inlet in the shield of the head of UAV, improving the drag characteristics and the stealthy performance of the aircraft; (3) The bump which is equal to the local boundary layer thickness in height can divert the boundary layer effectively. As a result, no obvious low total pressure zone is found at the outlet of the inlet; (4) According to the experimental results, negative angle of attack is favorable to the total pressure recovery and positive angle of attack is favorable to the total pressure distortion, while yaw brings bad effects on both; (5) The design of cowl lip is of great importance to the inlet performance at yaw, therefore, further improvement of the inlet performance will rely on the lip shapes of the cowl chosen.展开更多
针对运载火箭主动飞行段,设计一种适用于球头双锥整流罩的嵌入式大气数据测量系统(flush air data sensing,FADS),并进行运载火箭FADS实施方案和求解精度研究。采用风洞试验手段对迎角误差、侧滑角误差以及形压系数进行标定,结果表明:F...针对运载火箭主动飞行段,设计一种适用于球头双锥整流罩的嵌入式大气数据测量系统(flush air data sensing,FADS),并进行运载火箭FADS实施方案和求解精度研究。采用风洞试验手段对迎角误差、侧滑角误差以及形压系数进行标定,结果表明:FADS在飞行Mach数0.4~5.0范围内能够较为准确辨识出实时风场参数变化,攻角、侧滑角测量绝对误差小于0.5°,Mach数测量绝对误差小于0.1,静压相对误差小于5%。嵌入式大气数据测量技术在运载火箭风场实时修正、飞行控制和主动减载等专业领域具有广泛的应用前景。展开更多
文摘Combined with a UAV of the shape like Global Hawk, a new inlet is advanced to obtain high performance in both Radar Cross Section(RCS) and aerodynamic drag. Efforts are made to achieve this goal such as adopting a top-mounted inlet configuration, utilizing the diverterless technique and putting forward a new shape of entrance. A design method is brought forward and verified by wind tunnel tests. Results indicate: (1) Despite the negative effect of the front fuselage and the absence of the conventional boundary diverter, the performance of the top-mounted diverterless inlet advanced here(Ma:0.50-0.70, α:-4°-6°,σ>0.975) is equivalent to that of conventional S shaped inlet with diverter; (2) The integration of the inlet with the fuselage is realized by the utilization of a special inlet section and the diverterless technique, which disposes the whole inlet in the shield of the head of UAV, improving the drag characteristics and the stealthy performance of the aircraft; (3) The bump which is equal to the local boundary layer thickness in height can divert the boundary layer effectively. As a result, no obvious low total pressure zone is found at the outlet of the inlet; (4) According to the experimental results, negative angle of attack is favorable to the total pressure recovery and positive angle of attack is favorable to the total pressure distortion, while yaw brings bad effects on both; (5) The design of cowl lip is of great importance to the inlet performance at yaw, therefore, further improvement of the inlet performance will rely on the lip shapes of the cowl chosen.
文摘针对运载火箭主动飞行段,设计一种适用于球头双锥整流罩的嵌入式大气数据测量系统(flush air data sensing,FADS),并进行运载火箭FADS实施方案和求解精度研究。采用风洞试验手段对迎角误差、侧滑角误差以及形压系数进行标定,结果表明:FADS在飞行Mach数0.4~5.0范围内能够较为准确辨识出实时风场参数变化,攻角、侧滑角测量绝对误差小于0.5°,Mach数测量绝对误差小于0.1,静压相对误差小于5%。嵌入式大气数据测量技术在运载火箭风场实时修正、飞行控制和主动减载等专业领域具有广泛的应用前景。