재사용 우주발사체 액체로켓엔진용 터보펌프에 적용하기 위한 하이브리드 저널 베어링의 성능 예측

Abstract

Hybrid fluid film bearings are one of the key mechanical components for liquid rocket engine turbopumps in reusable launch vehicles to improve reliability and resuability of turbopumps. The main objective of the present research program at Hanyang University Turbomachinery Laboratory, analytical and experimental, is to advance fluid film bearing technology used in aerospace turbopumps. The current work presents the predicted performance of hybrid fluid film journal bearings for the test bearings at Hanyang University Turbomachinery Laboratory. Since the test bearings are lubricated with cold/warm/hot water as a surrogate test fluid for cryogenic oxidizer or propellant, the current bearing analysis uses water as a working fluid. Predictions show that the applied static load on the bearing significantly affects journal eccentricity ratio, flow rate, and direct force coefficients. Rotor speed shows a paramount effect on bearing attitude angle, friction power loss, and cross-coupled force coefficients.