箔片摩擦对波箔型径向气体轴承静刚度和悬浮转速影响实验

加工制造了两个不同轴承壳体圆柱孔内表面的表面粗糙度的波箔型径向气体轴承.在建立的波箔型径向气体轴承性能测试实验台上对预紧状态下两个波箔型径向气体轴承进行了静刚度测试实验,并利用摩擦力矩法测量了波箔型径向气体轴承的悬浮转速,通过对比两个轴承的实验结果分析了波纹箔片和轴承壳体之间的摩擦效应对轴承静刚度和悬浮转速的影响.结果表明:降低轴承壳体圆柱孔内表面的表面粗糙度能够减弱波纹箔片和轴承壳体之间的摩擦,减小了轴承静刚度,进而在轴承载荷相同的条件下有效降低了波箔型径向气体轴承的悬浮转速,减少了轴承表面磨损,对轴承结构设计和提高轴承寿命具有工程指导意义.此外,波箔型径向气体轴承的静刚度并不是线性的,而是随着箔片变形量的增大而增大,因此有必要在波箔型径向气体轴承理论建模时考虑箔片结构刚度的非线性特性.

Experiment of foil friction effect on static stiffness and lift off speed of bump foil journal bearing

Two bump foil journal bearings with different surface roughness of bearing housing's cylindrical hole surface were manufactured.The test-bed was established by exploiting bump foil journal bearing to test the static stiffness and lift off speed of bump foil journal bearings using friction torque method.By comparing test results of each bump foil journal bearing,the effects of friction between bump foil and bearing housing on static stiffness and lift off speed of bump foil journal bearing were studied.The results indicate that reducing surface roughness of bearing housing's cylindrical hole surface can weaken the friction between bump foil and bearing housing,decrease the bearing static stiffness and lift off speed under the same bearing load capacity.It has engineering significance to improve the bearing structure design and extend the bearing life due to lower the wear of bearing surface.Moreover,the static stiffness of bump foil journal bearing has strong nonlinear characteristic,and increases with the increasing foil deformation,so it is necessary to consider the nonlinear foil structural stiffness when modeling the bump foil journal bearing.