Static characteristics analysis of offset-halves journal bearings with CFD method considering turbulence and thermal effects

Purpose This study aims to develop a novel simulation model for offset-halves bearings that incorporates both turbulence effects and lubricant viscosity-temperature relationships, and to conduct the static characteristics of bearings under high-Reynolds-number operating conditions using this model. Design/methodology/approach The computational framework incorporates the k-ω shear-stress transport (SST) turbulence model to solve the hydrodynamic flow fields of both pads independently, using a finite-volume approach. Through customized post-processing algorithms, the computational fluid dynamics solutions are systematically integrated to determine the bearing’s static characteristics, accounting for turbulent flow effects and thermo-viscous lubricant behavior. Findings A comparative analysis with the Reynolds equation results revealed more pronounced turbulent effects in the unloaded pad at high rotational speeds, leading to significantly increased lubricant film pressure. Under the same journal center position, the turbulence effects cause substantially greater leakage flow rates with increasing speed. While the frictional forces show minimal differences from the Reynolds equation results across the entire speed range, the overall drag coefficients remain consistently higher than those predicted by the Reynolds equation. Originality/value This study presents original work and provides an effective analytical tool for investigating the operational characteristics of offset-halves bearings under high-Reynolds-number conditions. This research elucidates the influence of high rotational speeds on both the pressure distribution and static performance characteristics of offset-halves bearings. These findings establish a fundamental basis for subsequent investigations into the equilibrium positions and dynamic behaviors of offset-halves bearings under turbulent flow conditions.