Numerical simulations of the internal flow of rocket engines

High-performance supercomputers have greatly improved numerical studies due to their capabilities in computational fluid dynamics. This is true not only in the research of the physics governing natural phenomena, but also in industrial development where such fundamental physics is applied. This work discusses recent progress in finding an effective resolution of practical problems we face in development of the LE-7A rocket engine, which is used in the booster stage of the Japanese H-2A rocket. Understanding the physics of the internal flow of the rocket engine is essential for developing a highly reliable space-launch vehicle. Recent progress in computational fluid dynamics has changed our conventional approach to rocket engine development: trial and error, an iterative cycle of trial design and experimental verification. We explain the important role numerical study plays in the development of the rocket nozzle and turbopump of the LE-7A engine. We believe some of these problems will be solved in the near future using our numerical research and the Earth Simulator.