Prediction of static characteristics of cryogenic hybrid journal bearing for reusable pump-fed liquid rocket engine by computational fluid dynamics simulation.

This article focuses on the numerical analysis of cryogenic hybrid journal bearings used in liquid propellant rocket engine turbopumps to support reusable rocket technology. Using three-dimensional computational fluid dynamics (CFD) simulations incorporating turbulence and cavitation models, the study evaluates the internal flow behavior, static load capacity, and performance characteristics of methane-lubricated hybrid bearings under varying shaft eccentricities and pressure conditions. Results indicate that cavitation significantly affects pressure distribution and shaft load predictions, with neglecting cavitation leading to underestimation of load and overestimation of supply flow, while bearing power loss remains largely unaffected. The findings underscore the necessity of including cavitation effects in CFD analyses for accurate performance prediction of cryogenic hybrid bearings, with experimental validation planned to complement the simulations.