涡轮增压器织构化浮环轴承润滑数值模拟

为研究表面微织构对涡轮增压器浮环轴承在极端工况下润滑过程的影响，基于浮环轴承基本工作原理，以VT50半浮动轴承为研究对象，建立未织构、内织构和外织构3类浮环轴承内间隙三维润滑油膜模型，利用Fluent模拟获取润滑油速度及压力等信息。经研究获得以下结论：表面微凹腔的设置能够增强油膜承载能力，从而提高浮环轴承的工作平稳性，织构后最大平均油膜压力相对于未织构方案可提高1.92%；相对于外织构形式的动压作用，内织构形式通过挤压作用而在织构区域获得更高的油膜压力，前者油膜压力峰值可比后者高26.7%；在轴向润滑油出口区域附近设计微凹腔内织构是改善浮环轴承润滑性能的有效措施，可以防止轴承倾斜失效。

Numerical simulation on lubrication ontextured floating-ring bear for turbochargers

In the light of a VT50 semi floating-ring bear,three kinds of 3-D film models inside the inner clearance of the bear are built in order to investigate the effect of textures on the lubrication process of a floating-ring bear for turbocharger which works in a extremely hard condition based on its fundamental working principle.The three kinds of 3-D film models are non-texture model, inner-texture model and outer-texture model.The distribution of velocity field and pressure field of the lubricant are simulated by means of fluent software.The results from analysis and comparison show that the surface dimple textures possess the capability to enhance the carrying capacity of the lubrication film,which makes the bear work more smoothly and steadily,and the mean film pressure can increase by as much as 1.92% after partial texturing.The film pressure generated by the inner-texture model in the dimple area by squeezing effect is higher than that generated by the outer-texture model with dynamic pressure effect.The peak film pressure of former is 26.7% larger than that of the later.An effective method to improve the lubrication performance of the floating-ring bear is to design dimple inner-texture near the export area in the axial direction,which can restrain the failure caused by the inclining of the ring.