Multidisciplinary design optimization method for suborbital reusable launch vehicle

In order to figure out tight-coupling overall design problem of Suborbital Reusable Launch Vehicle (SRLV), the crucial technologies of Multidisciplinary Design Optimization (MDO) were investigated, namely task planning, discipline modeling, integration and solving strategy. A SRLV concept serving as the booster of orbital vehicle was selected as the baseline. First, the overall design task of SRLV was decomposed into seven disciplinary components including geometry, aerodynamics, structure, propulsion, trajectory, aero-heating, and thermal conduction/TPS design. The functions of disciplines and dataflow between them were defined. Then, the computational models of these disciplines were established, which met the requirements of overall design. Based on the task of SRLV, the MDO problems were presented, including objectives, constraints and variables. Within multidisciplinary framework software, the architecture of Multi-Disciplinary Feasible (MDF) was created. By integrating seven disciplinary models into MDF architecture, a MDO software system for SRLV overall design was established. Genetic Algorithm was chosen to optimize the take-off weight of SRLV. The obtained results show that the mass of propulsion structure and TPS parts both increase slightly, but the fuel mass and airframe structural mass decrease, and the take-off weight decreases about 2.4%.