基于CFD的新型结构静压油垫数值仿真技术

Numerical Simulation of the Hydrostatic Oil Pad With a New Structure Based on CFD

为了提高重载数控机床静压转台的承载能力和油膜刚度,提出了一种具有多环形流道油腔和阻尼型封油边结构的新型静压油垫,并对其性能进行了研究.在对静压油垫结构优化设计的基础上,利用CFD(computationalfluid dynamics)数值仿真技术,采用二维轴对称流动模型对新型结构静压油垫的流场特性进行了仿真分析,得到了新型静压油垫的内部流场特性,计算出油垫的承载能力和油膜刚度,并与单腔体、单平面封油边结构的静压油垫进行了对比.研究表明:新型静压油垫能通过在阻尼流道和阻尼槽内形成紊流,增加流动液阻,实现压力增益,并可在阻尼槽处产生局部静压效应,从而使新型结构静压油垫的承载能力和油膜刚度较传统结构静压油垫有所提高;此外,采用CFD技术有助于对复杂结构的静压油垫进行优化设计与性能计算,从而提高设计效率和计算准确性.

To improve the performance of heavy load and oil-film stiffness of an NC machine＇s hydrostatic turntable,a new structural hydrostatic oil pad with multi-ring flow channel oil recess and damping oil seal edge is put forward and proved.Combining with the optimization design of the hydrostatic oil pads and CFD technology,the flow model of two-dimensional axial-symmetry is used for numerical simulation.The inner flow,carrying capability,and stiffness of the new structure hydrostatic oil pad are analyzed and calculated.Moreover,these data are compared with those of the traditional oil pad that has a single-chamber and single-plane.Result shows that the hydrostatic oil pad of the new structure can make turbulence appear in the damp flow-passes and the damp grooves,enhance damping,make it available of higher pressure gain and get partial hydrostatic effectiveness in grooves.Therefore,it comes true to bear heavier load and generate stronger oil-film stiffness compared with the traditional oil pad.It is available for the optimization design and performance calculation of the complex structure hydrostatic oil-pad by CFD,which increases the efficiency of design and accuracy of calculation.The study of the new hydrostatic oil pad is important to improve the performance of the heavy load hydrostatic turntable.