摘要
大规格数控(CNC)成形磨齿机Z轴进给系统在加工过程中产生大量热量,导致立柱及导轨的倾斜、俯仰变形,影响加工精度。针对这一现象,提出了一种考虑接触热阻的瞬态热结构耦合分析方法。该方法基于分形理论计算结合面间的接触热阻,并计算热源发热量及各部件的对流换热系数,综合考虑内部热源、边界条件和接触热阻建立综合有限元模型,获得热误差有限元仿真结果。分析了在是否考虑接触热阻情况下,Z轴导轨温度及热变形变化差异。最后搭建Z轴进给系统热误差测量试验平台,验证了该方法的准确性和可靠性。通过仿真得到温度变化及热位移量与试验值基本一致。
The Z-axis feeding system of large computer numerical control(CNC)gear grinding machine tools generates a large amount of heat during the processing,which leads to tilt and pitch deformation of the Z-axis guideway and reduces the machining accuracy.In view of the above-mentioned facts,a transient thermal-structure coupling analysis method was proposed with thermal contact resistance(TCR)been taken into account.The thermal contact resistance at the joints was calculated using fractal theory.The heat from the source and the convective heat transfer coefficient of each component were calculated,and a comprehensive finite element model was established with regard to internal heat source,boundary condition and thermal contact resistance.Finite element simulation results of the thermal error were obtained.The temperature and thermal deformation of the Z-axis guideway were analyzed when thermal contact resistance was taken into consideration.The thermal error experimental platform of the Z-axis feeding system was set up,and the accuracy and reliability of the method were verified.Results showed that the temperature and thermal displacement were in accord with the experimental data.
作者
纪建都
孙付仲
洪荣晶
黄筱调
JI Jiandu;SUN Fuzhong;HONG Rongjing;HUANG Xiaodiao(College of Mechanical and Power Engineering,Nanjing Tech University,Nanjing 211800,China;Jiangsu Province Key Laboratory of Industrial Equipment Manufacturing and Digital Control Technology,Nanjing Tech University,Nanjing 211800,China)
出处
《南京工业大学学报（自然科学版）》
CAS
北大核心
2019年第6期710-715,共6页
Journal of Nanjing Tech University(Natural Science Edition)
基金
国家自然科学基金(51635003)
关键词
热特性
有限元法
接触热阻
分形理论
导轨
thermal characteristic
finite element analysis
thermal contact resistance
fractal theory
guideway
