Structural Optimization Of Hydrostatic Bearing Of Large-Typeball Mill Based On Surrogate Model

In recent years, in order to improve the production efficiency,the size of the ball mill is constantly becoming large. Because the performance of hydrostatic bearing directly affects the security of the mill, the hydrostatic bearing is put forward higher requirements. Therefore, it is significant to study the bearing performance, power loss and optimization design of the hydrostatic bearing to ensure the safety of the mill, improve the production efficiency and save energy consumption.Combined with the National Natural Science Foundation of China(51265020), oil film of hydrostatic bearing is studied in this paper. The influence of the shape and structure parameters of the recess on the bearing performance and power loss is discussed and analyzed. Then made the experiment test of the hydrostatic bearing. Finally, the structural parameters of the hydrostatic bearing were optimized. The main research works and conclusions are as follows:This paper introduces the structure and material of the hydrostatic bearing, and summarizes the influence factors of the performance of the hydrostatic bearing. By using CFD simulation technology, the influence of the shape, angle, width and offset angle of the recess on the performance of the hydrostatic bearing is analyzed. And in order to verify the correctness of the simulation method, the test of bearing is made. The results show that the structural parameters of the recess have great influence on the performance of the hydrostatic bearing, and the accuracy of the simulation method is proved by the test results.A method for constructing the surrogate model of hydrostatic bearing oil film is proposed. By using the Optimal Latin hypercube design method to design test scheme. The RSM method, Kriging method and RBF method were used to establish the oil film surrogate model, and the accuracy test and comparative analysis are done. The results show that the RBF model is suitable for the surrogate model of the oil film, the foundation is laid for the optimal design of the hydrostatic bearing.Structural optimization design of hydrostatic bearing of large-type ball mill is carried out. Under the requirements of the bearing working load, using MIGA optimization algorithm to carry on the single objective optimization and the MOPSO optimization algorithm to multi-objective optimization of bearing based on the oil film surrogate model. By using the TOPSIS method based on the grey relational degree, the optimal compromise solution of the Pareto solution set is selected. The optimized result and the original design were compared and analyzed. The results show that the single objective optimization design can only make a target better than the original design. And the performance of the multi-objective optimization design of hydrostatic bearings compared to single objective optimization design and the original design is better. the optimized hydrostatic bearing not only can improve the carrying performance, but also reduce the power loss.In this paper, through the CFD simulation calculation of the oil film of the hydrostatic bearing, the bearing capacity, the power loss and the pressure distribution of the oil film are obtained. The optimization design of hydrostatic bearing based on the surrogate model have great significance to improve the safety, production efficiency and energy consumption of large ball mill.