Simulation of Tribological Properties of Compound Dimple Bearing Considering Temperature Variation
Surface texturing is one of the main methods used to improve the tribological performance of bearings,and previous studies on microstructures mainly focused on a single-layer shape,such as rectangular,spherical,or cylindrical.However,in experimental and numerical simulation investigations of the tribological performance of textured lubricated bearings,the bearings have a single-layer pore shape and can only generate a dynamic pressure effect,which makes single-layer microtexture models in the reduction of friction,wear,and energy consumption insufficient for analyzing the performance.In addition,many recent studies on the tribological performance of textured water-lubricated bearings were based on isothermal assumptions but ignored the effect of temperature on the lubrication performance of bearings.This study mimicked the multilayered pore-like structure of circular-sieve algal shells and established a rectangular-hemispherical double-layered composite microtextured model to investigate the tribological performance of composite texturing-sized water-lubricated bearings.The model is applied to the high-pressure region of water-lubricated bearings and is based on the method of heat fluid-solid coupling to determine the water film load-carrying capacity of the water-lubricated bearing,the frictional force,and the friction factor effects.Inputs such as geometrical parameters from the literature were calculated,and the calculated water film load-carrying capacities were compared.The results were found to be consistent with results obtained from the literature,verifying the accuracy of the model.Based on this,the effects of the change in bearing speed and size of the double-layer composite texture on the tribological performance of composite textured water-lubricated bearings were investigated for different water inlet temperatures.The results indicate that for any water inlet temperature,the friction-reduction performance of double-layer composite textured bearings is better than those of smooth bearings and single-layer textured bearings.At a specific temperature,the higher the rotational speed,the higher the lubricating water-film pressure and the friction coefficient.At the same rotational speed,the water film pressure decreases with an increase in inlet water temperature when the inlet water temperature is low(20-50 ℃),whereas the coefficient of friction increases gradually.When the inlet water temperature increases to 50-60 ℃,the effects of temperature on the water film pressure and friction coefficient of the composite textured bearings gradually tend to stabilize.This indicates that the inlet temperature and bearing speed combine to influence the friction performance of the composite textured bearings.By changing the size of the composite textured structure,the inlet water temperature directly influences the friction performance of the composite textured bearing;the higher the inlet water temperature,the lower the water film pressure,but the coefficient of friction increases.At the same water inlet temperature,the size of the composite texture significantly influences the water film pressure but has a minimal effect on the coefficient of friction.This study promotes further breakthroughs in improving the tribological properties of water-lubricated bearings and provides a reference for related studies on reducing the frictional wear and extending the service life of bearings.
rectangular-spherical compound dimplewater-lubricated bearingsthermal-fluid-structure couplingfinite element analysis
万方数据
维普
