铝合金喷雾淬火界面换热系数的反分析求解

Determination of interfacial heat transfer coefficient of aluminum alloy during spray quenching based on inverse analysis method

喷雾淬火数值模拟过程中,界面换热系数的准确性直接影响到模拟精度。以6082铝合金喷雾淬火试验为基础,采用反分析法求解了界面热流密度和界面换热系数,并验证了反求结果的可靠性。结果表明：铝合金喷雾淬火过程中,界面换热经历了过渡沸腾、核沸腾和单相对流3个阶段,但不存在膜沸腾阶段;过渡沸腾阶段,随表面温度降低,界面热流密度迅速增大,界面换热系数近似呈线性增大;核沸腾阶段,随表面温度降低,界面热流密度缓慢减小,而界面换热系数迅速增大。

The accuracy of interfacial heat transfer coefficient directly influences the accuracy of numerical simulation of spray quenching.In this paper,based on the experiments of 6082 aluminum alloy spray quenching,the interfacial heat flux and heat transfer coefficient were solved by the inverse analysis method,and the reliability of the result was verified.The results show that the interfacial heat transfer has three regimes： transition boiling regime,nucleate boiling regime and single-phase regime in the spray quenching process.There is no film boiling regime.In the transition boiling regime,with the decrease of the surface temperature,the interfacial heat flux increases rapidly,and the interfacial heat transfer coefficient increases linearly.In the nucleation boiling regime,with the decrease of the surface temperature,the interfacial heat flux decreases slowly,while the interfacial heat transfer coefficient increases rapidly.