Optimization of oil-jet parameters for high-speed aeroengine bearings: CFD study with viscosity-temperature effect and experimental validation

To investigate the influence of oil-jet parameters on the lubrication and cooling performance of high-speed aeroengine bearings, the viscosity-temperature effect of lubricating oil was incorporated into a computational fluid dynamics (CFD) solver for numerical simulations in this study. Experimental validation demonstrates that, within the investigated rotational speed range, the maximum relative error in outer ring temperature predicted by the CFD model without considering the viscosity-temperature effect reaches 20.58%. In contrast, this error is reduced to only 6.5% when the viscosity-temperature effect is included, which significantly improves the numerical accuracy. On this basis, the validated CFD model is used to systematically analyze the effects of injection pitch angle, horizontal angle, and injection pressure on the lubrication and cooling performance of the inner raceway. The results show that after single-factor optimization, the average temperature of the inner raceway is reduced by 17.34 °C relative to the original configuration. Multi-factor coupled optimization via the Taguchi method reveals that the injection pitch angle consistently serves as the dominant factor affecting both lubrication and cooling performance. When targeting the minimum inner raceway temperature as the optimization objective, the multi-factor optimization configuration reduces the average inner raceway temperature by 30.14 °C relative to the original configuration, achieving a better cooling effect than single-factor optimization.