Hybrid search multi-discipline feasible design optimization of a typical Space Launch Vehicle

This paper presents design of a typical Space Launch Vehicle (SLV) using multidisciplinary design optimization (MDO) Methodology. A one level MDO structure, Multi-Discipline Feasible (MDF) has been used. A Hybrid Search Algorithm (HSA), which associates Simulated Annealing (SA) as a global optimizer with Simplex as a local optimizer is employed. The main objective of this multi-disciplinary design is minimizing the gross lift off mass (GLOM) of the vehicle that is an impetus driver on vehicle performance and cost. The main disciplines that are considered for this design include propulsion and weight, aerodynamic and trajectory simulation. The SLV design variables and the orbital insertion trajectory profile variables despite mission and flight trajectory constraints are optimized simultaneously, whereas the mass characteristics of the vehicle were assigned. The optimized SLV is capable of delivering a small satellite of 250 kg to a circular orbit of 900 km altitude. Simulation results demonstrate the superior performance of the HSA over challenging MDO problems. Optimal design shows the GLOM reduction about 7.0%, which is quite significant at conceptual design level.