为了更加有效地减小民用客机考虑配平约束后的阻力,针对典型跨声速民用客机机翼-机身-平尾构型研究了不同静稳定度下的气动优化设计,并总结出在民用客机的减阻设计中考虑放宽静稳定度具有较大的减阻潜力。通过自由型面变形(FFD)技术对...为了更加有效地减小民用客机考虑配平约束后的阻力,针对典型跨声速民用客机机翼-机身-平尾构型研究了不同静稳定度下的气动优化设计,并总结出在民用客机的减阻设计中考虑放宽静稳定度具有较大的减阻潜力。通过自由型面变形(FFD)技术对全机外形进行参数化,实现机翼型面的变形,进行气动优化设计并改变平尾的偏转保证全机能够力矩配平。采用基于雷诺平均Navier-Stokes(RANS)方程的离散伴随方法求解目标函数对设计变量的梯度,然后基于序列二次规划算法进行基于梯度的气动优化设计。基于CRM(Common Research Model)构型,针对不同参考重心位置进行了考虑配平约束的减阻优化设计研究,验证了优化设计系统的有效性,算例结果表明,随着重心位置后移即放宽静稳定度,优化构型配平阻力减小,外翼段前缘吸力峰值明显降低且双激波的强度得到有效减弱,此外机翼的升力系数分布更加贴合最佳升力系数分布。展开更多
Since the aerodynamic center moving backward sharply in hypersonic flight,the stability margin of the hypersonic vehicle increases largely while the maneuverability decreases.We proposed a novel method to solve this c...Since the aerodynamic center moving backward sharply in hypersonic flight,the stability margin of the hypersonic vehicle increases largely while the maneuverability decreases.We proposed a novel method to solve this contradiction.We used relaxed static stability(RSS)to improve the maneuverability in hypersonic flight,and designed the stability augmentation system(SAS)to ensure the stability in subsonic flight.Therefore,the relationship between static stability and maneuverability was quantitatively analyzed in the first step,and the numerical value of RSS was obtained on the premise of good maneuverability.Secondly,the relationship between static stability and aerodynamic parameters was quantitatively analyzed.We properly adjusted aerodynamic parameters based on the quantitative relationship to achieve the specific static stability set in the first step,and therefore provided the engineering realization methods.The vehicle will be statically unstable in subsonic flight with the specific static stability.Lastly,SAS was needed to ensure the stability of the vehicle in subsonic flight.Simulation studies were conducted by comparing the linear SAS to the nonlinear SAS,and the results showed that the nonlinear dynamicinversion controller can synthesize with proportional-integrall-derivative(PID)controller robustly and stabilize the hypersonic vehicle.展开更多
文摘为了更加有效地减小民用客机考虑配平约束后的阻力,针对典型跨声速民用客机机翼-机身-平尾构型研究了不同静稳定度下的气动优化设计,并总结出在民用客机的减阻设计中考虑放宽静稳定度具有较大的减阻潜力。通过自由型面变形(FFD)技术对全机外形进行参数化,实现机翼型面的变形,进行气动优化设计并改变平尾的偏转保证全机能够力矩配平。采用基于雷诺平均Navier-Stokes(RANS)方程的离散伴随方法求解目标函数对设计变量的梯度,然后基于序列二次规划算法进行基于梯度的气动优化设计。基于CRM(Common Research Model)构型,针对不同参考重心位置进行了考虑配平约束的减阻优化设计研究,验证了优化设计系统的有效性,算例结果表明,随着重心位置后移即放宽静稳定度,优化构型配平阻力减小,外翼段前缘吸力峰值明显降低且双激波的强度得到有效减弱,此外机翼的升力系数分布更加贴合最佳升力系数分布。
基金supported in part by the National Natural Science Foundation of China(Nos.61673209,61741313)the Funding of Jiangsu Innovation Program for Graduate Education(No.CXZZ13_0170)+3 种基金the Funding for Outstanding Doctoral Dissertation in NUAA(No.BCXJ13-06)the Jiangsu Six Peak of Talents Program(No.KTHY-027)the Funding of China Launch Vehicle Technology Innovation Program of University and Institute(No.CALT201503)the Aeronautical Science Foundation(No.2016ZA52009)
文摘Since the aerodynamic center moving backward sharply in hypersonic flight,the stability margin of the hypersonic vehicle increases largely while the maneuverability decreases.We proposed a novel method to solve this contradiction.We used relaxed static stability(RSS)to improve the maneuverability in hypersonic flight,and designed the stability augmentation system(SAS)to ensure the stability in subsonic flight.Therefore,the relationship between static stability and maneuverability was quantitatively analyzed in the first step,and the numerical value of RSS was obtained on the premise of good maneuverability.Secondly,the relationship between static stability and aerodynamic parameters was quantitatively analyzed.We properly adjusted aerodynamic parameters based on the quantitative relationship to achieve the specific static stability set in the first step,and therefore provided the engineering realization methods.The vehicle will be statically unstable in subsonic flight with the specific static stability.Lastly,SAS was needed to ensure the stability of the vehicle in subsonic flight.Simulation studies were conducted by comparing the linear SAS to the nonlinear SAS,and the results showed that the nonlinear dynamicinversion controller can synthesize with proportional-integrall-derivative(PID)controller robustly and stabilize the hypersonic vehicle.