Weight Optimization of Liquid Rocket based in Gas-generator Cycle

초록

In this study, the analysis and optimization program of the propulsion system of the launch vehicle has been developed for suggestion of the basis of the minimum weight of the launch vehicle which satisfies the mission velocity and altitude. Since launch vehicle weight has a huge effect on the launch vehicle cost and payload weight, the design procedure for the ideal launch vehicle weight compared to the engine thrust is required. Analysis modules for thrust chamber, turbo-pump, and gas-generator have been composed for the launch vehicle system. Using the genetic algorithm, the optimization program has been designed to find the minimum weight of the launch vehicle within ranges of design variables. Design variables were determined as chamber pressure, nozzle expansion ratio and launch vehicle thrust-to-weight ratio which are the principal parameters of the launch vehicle. As the program execution results, 8~11% weight reductions of the launch vehicle has been estimated compared to the existing launch vehicles. It has been possible to obtain the optimal variables of thrust geometry, turbo-pump power, and gas-generator mass flow rate.