有动力通用再入飞行器的轨迹设计与优化

研究了有动力通用再入飞行器的燃料最优巡航轨迹，将问题转化为求解最优稳态巡航轨迹和最优周期巡航轨迹问题。基于稳态动力学方程求解了全局最优稳态巡航轨迹，采用直接打靶法求解了最优周期巡航轨迹，求解过程均考虑了质量变化。结果表明，与全局最优稳态巡航轨迹相比，在一个周期内，最优周期巡航轨迹在燃料消耗和吸热量两个方面都更具优势，采用超燃冲压发动机和火箭发动机分别可以节省4.75%和3.96%的燃料，吸热量分别减小10.4%和5.9%。

Trajectory Design and Optimization of Powered Common Aero Vehicles

The fuel optimal cruise trajectory of a powered common aero vehicle was analyzed. The problem was divided into determining the optimal steady-state cruise and optimal periodic cruise problems. The global optimal steady-state cruise trajectory was determined based on steady-state dynamic equations. The optimal periodic cruise trajectory was solved by the direct shooting method. The decrease of vehicle mass was considered in each case. The result shows that compared with the global optimal steady-state cruise trajectory the periodic cruise trajectory achieves better fuel consumption and heat load performances in one period. The fuel savings of 4.75% with a scramjet engine and 3.96% with a rocket engine are achieved by the optimal periodic cruise trajectory over the optimal steady-state cruise trajectory. The heat loads are respectively 10.4% and 5.9% lower than those of the optimal steady-state cruise trajectory.