数值模拟热物性参数反求技术研究及其在轨道交通铸件中的应用

Inverse Technology for Numerical Simulation of Thermophysical Parameters and its Application in Castings for Rail Transit Vehicles

通过测定不同种类的合金材料、砂型和冒口的铸件实际降温曲线,来优化热物性参数,提高碱酚醛树脂砂仿真精度。首先,基于华铸CAE与参数反求技术,在不同条件下对铸件开展正交试验,建立铸件的降温曲线。其次,对于各类铸件实际测温,并对比与降温曲线的相似度,进行误差分析。最后,根据对比结果选取与实测的降温曲线最接近的模拟曲线,确定热物性参数。正交试验表明,当温度在1000℃~1500℃时,反求之后的实际测温曲线与模拟曲线的相似度大于95%,两者吻合良好。

Inverse calculation of thermophysical parameters is very important for improving the accuracy of numerical simulation.Thermophysical parameters are optimized and the simulation accuracy of alkali phenolic resin sand is improved by means of measuring the actual cooling curves of castings related to different kinds of alloy materials,sand molds and risers.Firstly,orthogonal experiments of castings are carried out under different conditions based on CAE and parametric inverse technology of HUST to establish the cooling curves of the castings.Secondly,error analysis is implemented through actual temperature measurement of various castings and comparison of similarity of cooling curves.Finally,the simulation curve nearest to the actually measured cooling curve is selected according to the comparison result to determine the thermophysical parameters.The orthogonal experiment shows that the similarity between the actual temperature measurement curve and the simulated curve is greater than 95%at the temperature between 1000℃and 1500℃after the inverse calculation,and the two curves match well.