摘要
为了更准确地对电主轴系统进行温度场的预测,建立了综合考虑接触热阻、轴承热变形和气隙变化等因素影响的热网络模型和热结构耦合热网络瞬态温度平衡方程(简称热平衡方程)。首先计算了接触热阻、轴承热变形、电机的定子与转子由于热变形导致的气隙变化以及电机与轴承的生热;然后选择电主轴主要部件作为温度节点,建立了电主轴系统的热网络模型及热平衡方程;最终通过MATLAB软件编程进行热平衡方程的求解,得到电主轴各主要部件的瞬态温度变化情况,通过不断更新接触热阻、轴承生热和电机生热等热特性参数,对电主轴进行温度和结构变形的耦合计算。计算结果表明:在达到平衡状态前,电主轴运转的时间越长,轴承的温度越高,轴承生热功率越低;电机温度随对流换热系数增高而降低;考虑热特性参数变化的热计算所得到的结果更加准确。通过与相同条件下的热结构耦合仿真结果进行对比表明,该热网络瞬态温度模型(热网络模型)可以正确预测温度场分布。
In order to predict the temperature field of the motorized spindle system more accurately,the transient temperature balance equations(thermal balance equation)of thermal structure coupled thermal network and thermal network model were established,which comprehensively considers the influence of contact thermal resistance,bearing thermal deformation and air gap change.Firstly,the contact thermal resistance,thermal deformation of bearing,air gap change caused by thermal deformation of motor stator and rotor,and heat generation between motor and bearing were calculated;then,the main components of the motorized spindle were selected as the temperature nodes,and the thermal network model and thermal balance equation of the motorized spindle system were established;finally,the thermal balance equation was solved by MATLAB software programming,and the transient temperature changes of the main parts of the motorized spindle were obtained.The coupling calculation of the temperature and structural deformation of the motorized spindle was carried out by constantly updating the thermal characteristic parameters such as contact thermal resistance,bearing heat generation and motor heat generation.The results shows that the longer the spindle runs,the higher the temperature of the bearing and the lower the heat generating power of the bearing;The temperature of the motor decreases as the convective heat transfer coefficient increases;the results of thermal calculations taking into account the changes in thermal characteristics are more accurate.Compared with the simulation results of thermal structure coupling under the same conditions,it shows that the transient temperature model(thermal network model)can correctly predict the temperature field distribution.
作者
高震
齐向阳
常雷
丁超
GAO Zhen;QI Xiangyang;CHANG Lei;DING Chao(School of Mechanical Engineering,Tiangong University,Tianjin 300387,China)
出处
《现代制造工程》
CSCD
北大核心
2021年第6期75-82,共8页
Modern Manufacturing Engineering
基金
国家重点研发计划项目(2018YFB1701201)。
关键词
电主轴
热网络法
热结构耦合
接触热阻
motorized spindle
thermal network method
thermal structure coupling
contact thermal resistance
