Abstract: The hydrostatic rotary table’s upper and lower guides are prone to scratch each other when the partial loaded hydrostatic rotary table is rotating. In the former study of this phenomenon, it is hard to establish a practical mathematical model of carrying capacity and overturning moment of the hydrostatic rotary table based on traditional analytical calculating method, and the modeling and calculating of fluid domain with a changing geometrical boundary can not be conducted when utilizing the traditional CFD simulation method. To solve this problem, a new calculation method based on dynamic mesh model is proposed, which is used to calculate the bearing capacity and overturning moment of the partial loaded hydrostatic rotary table under rotating condition in engineering practice. The change of oil film form is controlled by using user definition function. Deformation of oil film mesh caused by the changing of rotary table’s tilting direction is refreshed using spring smoothing theoretical model. The oil film’s moving boundary caused by rotational movement is changed into static boundary for avoiding the grid distortion. This method can realize the simulation of oil film with different thickness and tilt displacement rate using the same model, which can avoid the repeatedly building of calculating model and improving the computational efficiency. The dynamic process of three dimensional pressure distribution of oil film is reappeared. The impact of rotary table’s motion on flow field distribution can be reflected in the calculating result which is closer to engineering practice. The bearing capacity and overturning moment of a typical hydrostatic rotary table are calculated by using the proposed method and the experiment of hydrostatic rotary table bearing partial load is conducted. The experimental results are in reasonable agreement with calculation ones, which have verified the effectiveness of the proposed calculating method.

Key words: bearing capacity, dynamic mesh, hydrostatic rotary table, overturning moment, partial load