金属凝固过程界面换热系数的Tikhonov正则化辨识

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.

Tikhonov Regularization Determination of Interfacial Heat Transfer Coefficient in Metal Solidification

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-posedness of inverse heat conduction problems(IHCP).It shows better accuracy especially with increasing error of measurement temperature.