多级固体运载火箭分级多学科设计优化

为了解决固体运载火箭总体优化过程中学科耦合性强、计算复杂、设计效率低等问题,建立了多级固体运载火箭的几何外形、质量、气动、推进、弹道/制导等学科模型,将多级运载火箭分成若干个子级火箭,并通过级间飞行状态连续性条件连接到一起,形成系统级和子系统级的框架。设计了并行方式和串行方式2种子系统的优化流程,以起飞总重最小为目标进行了多学科设计优化(MDO)。结果显示,这2种分级优化的方法与多学科可行(MDF)方法相比能减小优化过程中的迭代次数,得到更好的优化结果,从而验证了分级优化方法在多级固体运载火箭MDO的可行性与优越性。

Stage-wise multidisciplinary design optimization for multi-stage solid launch vehicle

Because of the strong coupling of multi-disciplines and the complicated algorithm and the low design efficiency, the integral optimization design of solid launch vehicle is a difficult, but important problem. To solve this problem, the multidisciplinary models of a multi-stage solid launch vehicle, including geometry, mass, aerodynamic, propulsion and trajectory/guidance systems, were established. Then, the multi-stage solid launch vehicle was divided into several sub-stages which were connected by the continuous requirements of the flight states. Thus, the system-level and subsystem-level solution frameworks were constructed. Furthermore, two types of optimization processes, named parallel and serial methods, were presented to solve the multidisciplinary design optimization (MDO) problem where the objective function is to minimize the gross weight. The results show that via the stage-wise formulation, the number of iterations can be reduced and better results can be obtained,compared with the traditional multidisciplinary feasible (MDF) method, and thus we verify the feasibility and superiority of the proposed approach applied to MDO problems for multi-stage solid launch vehicles.