基于环形非均匀热源的磨削温度场建模与实验研究

Modeling and Experimental Study of Grinding Temperature Field Based on Annular Non-uniform Heat Source

目的解决杯形砂轮平面磨削复合材料时的热损伤及温度实时监测困难等问题,对磨削温度场的动态变化规律进行相关研究。方法通过分析杯形砂轮平面磨削时材料的去除机理,在柱坐标系下提出周向和径向呈不同函数分布的非均匀热源模型,并基于该模型建立磨削温度场的数值模型用于预测磨削温度,最后提出杯形砂轮平面磨削时磨屑带走热量所引起温度预测误差的计算方法。开展人工热电偶测温验证实验,对比不同热源模型下的预测值和实验值,验证非均匀热源及其温度场数值模型的准确性。结果相较于均匀热源下的温度场,非均匀热源下的温度场与实际温度场具有更高的吻合度,将温度预测的误差从约23%降低到6.5%以下。结论磨削深度对磨削温度具有较大的影响,且在进行高效深磨的时,为保证温度预测的精度,需考虑磨屑带走热量所引起的误差。

The paper aims to solve the problems of thermal damage and difficulty in real-time temperature monitoring in surface grinding of composite materials by cup wheel and study the dynamic variation law of grinding temperature field. In this paper, by analyzing the material removal mechanism in surface grinding by cup wheel, a non-uniform heat source model under cylindrical coordinate system with different function distribution in circumference and radial direction was proposed. And based on this model, an numerical model of grinding temperature field was established to predict grinding temperature. Finally, a calculation method of temperature prediction error caused by heat carried away by debris was proposed. The validation experiments of thermocouple temperature measurement were carried out, and the predicted and experimental values under different heat source models were compared to verify the accuracy of the non-uniform heat source and its temperature field model. Compared with the temperature field under the uniform heat source, which under the non-uniform heat source was more agreement with the actual temperature field, and the error of temperature prediction was reduced from about 23% to within 6.5%. The experimental results show that grinding depth has a great influence on grinding temperature. To ensure the accuracy of temperature prediction, it is necessary to consider the error caused by heat carried away by debris during high efficiency deep grinding.