Coupled effects of surface texture and temperature-induced viscosity changes on journal bearing performance

Abstract Surface texturing consists of introducing well-defined, intentional cavities on bearing surfaces, either on the housing or on the rotating shaft. For such configurations, it is well established in the literature that mass-conserving cavitation models are essential for accurately describing cavitation phenomena. However, the influence of thermal effects on the performance of textured bearings is often overlooked. This work addresses this gap by proposing a mass-conserving two-phase cavitation model that incorporates global thermal effects to assess the impact of surface texturing on load-carrying capacity, friction and temperature in hydrodynamic journal bearings. The pressure predictions are validated against full Navier-Stokes CFD simulations, while the friction and thermal responses are validated using experimental data for both smooth and textured bearings. The results demonstrate that friction-induced temperature rises modify bearing performance in the presence of textures, confirming that thermal effects are a critical factor and that conventional isothermal assumptions may be misleading for the accurate analysis and design of textured journal bearings.