Simulation study on the influence of the structure of the cooling water jacket of the motorized spindle on thermal characteristics

As a core component of high-end CNC machine tools, the thermal characteristics of motorized spindles directly affect the machining accuracy and operational stability of the machine tool. To improve the thermal control performance of motorized spindles under high rotational speed, this paper carries out a systematic study for the optimization of the cooling water jacket structure. The internal heat generation model of the motorized spindle is constructed and verified with the temperature measurement, and then the thermal characteristics of four typical cooling water jacket structures, U-Type, DH-Type, SH-Type and T-Type, are compared with each other based on the CFD simulation method. The results show that the T-Type is excellent in temperature control capability and uniformity. On this basis, the key parameters of the T-Type structure are further optimized, and the effects of the parameters on the flow characteristics and heat transfer efficiency are examined. It was found that vortex scale size, formation of counter-rotating vortex pairs and stagnation zone affect cooling efficiency and temperature uniformity.