文章针对高超声速可变形减速器的飞行稳定性预测及回收着陆需求,研究表面结构变形对减速器气动特性的影响效应,重点分析了高度10~50 km、Ma=0.15~4.6关键速域内的静、动态气动特性变化。文章采用求解雷诺平均Navier-Stokes方程(Reynolds...文章针对高超声速可变形减速器的飞行稳定性预测及回收着陆需求,研究表面结构变形对减速器气动特性的影响效应,重点分析了高度10~50 km、Ma=0.15~4.6关键速域内的静、动态气动特性变化。文章采用求解雷诺平均Navier-Stokes方程(Reynolds average Navier-Stokes,RANS)的数值模拟方法,获得了有无表面结构变形减速器的流场和气动参数。定常计算结果表明:变形效应导致飞行器迎风面存在局部的小尺度流动分离,变形后外形的气动阻力增加。结合刚性动网格技术的俯仰强迫振动,计算结果表明:减速器的动态稳定性受到迎风面高压及背风面分离涡结构的共同作用,迎风面的高气动压力载荷占主导作用,使得减速器的动态稳定性增强;背风面的涡结构导致动态稳定性减弱;轴对称分布的表面结构变形整体上增强了减速器的动态稳定性。展开更多
This paper proposed a new libration decoupling analytical speed function(LD-ASF)in lieu of the classic analytical speed function to control the climber's speed along a partial space elevator to improve libration s...This paper proposed a new libration decoupling analytical speed function(LD-ASF)in lieu of the classic analytical speed function to control the climber's speed along a partial space elevator to improve libration stability in cargo transportation.The LD-ASF is further optimized for payload transportation efficiency by a novel coordinate game theory to balance competing control objectives among payload transport speed,stable end body's libration,and overall control input via model predictive control.The transfer period is divided into several sections to reduce computational burden.The validity and efficacy of the proposed LD-ASF and coordinate game-based model predictive control are demonstrated by computer simulation.Numerical results reveal that the optimized LD-ASF results in higher transportation speed,stable end body's libration,lower thrust fuel consumption,and more flexible optimization space than the classic analytical speed function.展开更多
文摘文章针对高超声速可变形减速器的飞行稳定性预测及回收着陆需求,研究表面结构变形对减速器气动特性的影响效应,重点分析了高度10~50 km、Ma=0.15~4.6关键速域内的静、动态气动特性变化。文章采用求解雷诺平均Navier-Stokes方程(Reynolds average Navier-Stokes,RANS)的数值模拟方法,获得了有无表面结构变形减速器的流场和气动参数。定常计算结果表明:变形效应导致飞行器迎风面存在局部的小尺度流动分离,变形后外形的气动阻力增加。结合刚性动网格技术的俯仰强迫振动,计算结果表明:减速器的动态稳定性受到迎风面高压及背风面分离涡结构的共同作用,迎风面的高气动压力载荷占主导作用,使得减速器的动态稳定性增强;背风面的涡结构导致动态稳定性减弱;轴对称分布的表面结构变形整体上增强了减速器的动态稳定性。
基金funded by the National Natural Science Foundation of China(12102487)Basic and Applied Basic Research Foundation of Guangdong Province,China(2023A1515012339)+1 种基金Shenzhen Science and Technology Program(ZDSYS20210623091808026)the Discovery Grant(RGPIN-2024-06290)of the Natural Sciences and Engineering Research Council of Canada。
文摘This paper proposed a new libration decoupling analytical speed function(LD-ASF)in lieu of the classic analytical speed function to control the climber's speed along a partial space elevator to improve libration stability in cargo transportation.The LD-ASF is further optimized for payload transportation efficiency by a novel coordinate game theory to balance competing control objectives among payload transport speed,stable end body's libration,and overall control input via model predictive control.The transfer period is divided into several sections to reduce computational burden.The validity and efficacy of the proposed LD-ASF and coordinate game-based model predictive control are demonstrated by computer simulation.Numerical results reveal that the optimized LD-ASF results in higher transportation speed,stable end body's libration,lower thrust fuel consumption,and more flexible optimization space than the classic analytical speed function.