表面织构对液钠动静压滑动轴承润滑特性的影响研究

Study on influence of surface texture on lubrication characteristics of liquid sodium hybrid plain bearing

随着二回路主循环泵不断朝大容量、高负荷的方向发展,对其关键承载部件——液钠动静压滑动轴承(简称液钠轴承)的润滑特性提出了更高的要求。为了进一步提升液钠轴承的润滑特性,通过数值模拟和试验相结合的方法研究了表面织构对其润滑特性的影响。首先,设计了圆形、正方形和菱形三种不同形状的表面织构,在对液钠轴承摩擦副模型进行简化后,采用数值模拟方法分析了3种表面织构在不同深度和不同间距下所呈现的润滑特性。然后,探究了激光加工参数对表面织构制备的影响,并制备了带有不同形状、不同间距表面织构的摩擦副试样,用于开展摩擦磨损试验。最后,对计入表面织构的液钠轴承模型进行了分析。结果表明:不同形状的表面织构均存在最优深度和间距,其中菱形织构在无量纲深度为2、间距为1.4 mm时具有最佳的润滑特性;计入菱形织构后液钠轴承的承载力和刚度系数分别提升了16.7%和9.3%,摩擦系数降低了13.1%。研究结果对二回路主循环泵及钠冷快堆系统的安全可靠运行具有重要意义,可为同类轴承的优化设计和国产化提供重要参考。

As the secondary loop main circulation pumps progress towards larger capacity and higher loads,higher requirements are placed on the lubrication characteristics of its key load-bearing component,which is the liquid sodium hybrid plain bearing(referred to as liquid sodium bearing).To further improve the lubrication characteristics of liquid sodium bearing,the influence of surface texture on its lubrication characteristics was studied through the combination method of numerical simulation and test.Firstly,the surface textures with circular,square and rhombic shapes were designed.After simplifying the friction pair model of liquid sodium bearing,the lubrication characteristics of three surface textures under different depths and different spacing were analyzed by numerical simulation method.Then,the influence of laser processing parameters on the surface texture preparation was explored,and the friction pair specimens with surface textures of different shapes and different spacing were prepared for friction and wear testing.Finally,the liquid sodium bearing model incorporating surface textures was analyzed.The results indicated that the surface textures with different shapes had optimal depth and spacing,and the rhombic texture had the best lubrication characteristics when the dimensionless depth was 2 and the spacing was 1.4 mm.After incorporating rhombic textures,the bearing capacity and stiffness coefficient of liquid sodium bearing increased by 16.7%and 9.3%,respectively,and the friction coefficient decreased by 13.1%.The research results are of great significance for the safe and reliable operation of secondary loop main circulation pumps and sodiumcooled fast reactor systems,and can provide important reference for the optimization design and localization of similar bearings.