Research On Experiment And Simulation Of Thermal Properties Of Motorized Spindle Based On Fluid-Solid-Heat Coupling

The application of motorized spindle technology has greatly contributed to thedevelopment of machine tool industry, but the generating heating problem ofmotorized spindle seriously influences the machine accuracy. Reasonably controllingthe spindle generating heat, reducing the spindle thermal deformation, and improvingthe spindle stress distribution are of important significance to improvement of thethermal characteristics of motorized spindle. The research on motorized spindlethermal characteristics includes three aspects: heat modeling of spindle, FEMsimulation and motorized spindle test. The following research works have beencompleted.The thermal characteristics of spindle, thermal deformation theory and coolingmode were analyzed from the researching of spindle heat source. Two kinds of motorheat model were established, and different boundary conditions were introduced forthe modeling method. Spindle power, spindle speed, lubrication and other factorswere considered in the modeling of bearing, and the usable calculations were given.According to the fluid-solid-heat coupling theory, the FEM software Workbenchwas used to finish the motorized spindle analysis. In the finite element analysis,Spindle speed, coolant inlet temperature, coolant flow rate and bearing preload wereconsidered. In certain conditions, optimal coolant inlet temperature and coolant flowwere obtained by FEA. The finite element simulation analysis conclusion can supportthe thermal balance design of motorized spindle. This paper introduced the process ofFEM simplification, and the modeling method of cooling system. Different thermalloads and boundary conditions were calculated to ensure the accuracy of the spindlethermal properties of finite element analysis.The temperature and thermal deformation test system has been established based onNI acquisition module. The spindle thermal characteristics test system has been builtbased on infrared thermograph, and stress test system. On the basis of theexperimental study on thermal performance of motorized spindle, temperaturedistribution, thermal deformation law of spindle, the characteristic of thermal stress,were obtained by the experiment, and the cooling strategy of motorized spindle underdifferent working conditions has been gained. Experimental data were compared with the results of finite element analysis, and the rationality and validity of finite elementanalysis has been verified.The above research methods and results can be applied into the thermal balancedesign and thermal characteristic study of motorized spindle.