高档数控机床静压转台双环形油腔流场特性仿真

为了提高高档数控机床的加工精度和稳定性,设计了一种新型的双环形油腔结构。基于流体动力学理论,并采用计算流体动力学(Computational Fluid Dynamics,CFD)数值模拟方法,研究了入口雷诺数对油腔内部流场结构和油腔承载力的影响。结果表明:入口雷诺数对于油腔内部流场结构和油腔承载力均具有重要影响;随着入口雷诺数的增大,油腔中心凹槽内部由单胞对流发展成多胞对流;同时,油腔承载力也相应增加。通过与传统圆形油腔对比发现,在相同入口雷诺数条件下,双环形油腔具有更高的承载力。该研究对设计高档数控机床新型油腔结构、优化油腔几何结构、提高承载力和加工精度有指导意义。

Numerical Simulation of Flow Field Characteristics in Double-rings Oil Pad in Hydrostatic Turntable of CNC Machine Tools

To improve the machining accuracy and stability of high-level CNC machine tools, a new type of double-rings oil pad was designed. Based on fluid dynamics theory and computational fluid dynamics (CFD) method, the influences of inlet Reynolds numbers on flow field characteristics inside the oil pad and the bearing capacity were numerically simulated. The simulation results show that the inlet Reynolds number has an important influence on the internal flow field structure and bearing capacity of the oil pad. With the increase of the inlet Reynolds number, single vortex cell convection develops into multi vortex cells convection in the central groove of the oil pad. Moreover, the bearing capacity of the oil pad increases accordingly. Compared with the traditional circular oil pad, it is found that the double-rings oil pad has higher bearing capacities than the circular oil pad under the same inlet Reynolds number. The results have guiding significance for designing new oil pads, optimizing oil pad geometry, improving bearing capacity and machining accuracy of high-level CNC machine tools.