Axial thrust behavior in LOX-pump of rocket engine

The LOX pump of the first stage of the H-Ⅱ rocket, the generation of large launch vehicle in Japan, has shown fairly good axial thrust performance. However, the behavior the axial thrust is not well known because of the complicated thrust balancing device and to improve it, the internal flow in the device was fully analyzed by developing a method of boundary value determination at each element composing the device. The analysis developed here was confirmed to give satisfactory results by comparison with actual measurements. Using the present analysis, the axial thrust behavior of the LOX pump was revealed for various combinations of balancing piston, balancing holes, swirl breaker, etc.