金属凝固过程界面换热系数的Tikhonov正则化辨识
Tikhonov Regularization Determination of Interfacial Heat Transfer Coefficient in Metal Solidification
-
摘要: 金属凝固过程中,铸件与铸型间的界面换热系数是数值模拟所必需的边界条件之一.充分考虑非线性瞬态热传导过程测温数据的误差特点,根据Tikhonov正则化理论,构造合适的正则化泛函,利用Arcangeli准则和Morozov偏差原理确定正则参数,采用灵敏度系数和Newton-Raphson迭代法求解该泛函.具体的案例分析表明,该方法克服了热传导反问题的不适定性,能够保证辨识结果的稳定性和精度.与其他方法相比,随着测温误差的增大,该方法具有较高的辨识精度.Abstract: Interfacial heat transfer coefficient (IHTC) between casting and mould is an essential boundary condition in simulation of metal solidification. We present an inverse method based on Tikhonov regularization theory. A regularized functional is established and regularization parameters are deduced with Arcangeli criterion and Morozov discrepancy principle. The functional is solved by sensitivity coefficients and Newton-Raphson iteration method. The regularization method ensures stability and accuracy of determination and overcomes ill-pesedness of inverse heat conduction problems (IHCP). It shows better accuracy especially with increasing error of measurement temperature.