Random Dynamic Load Identification Under Thermal–Mechanical Coupling for Aircraft Wing Structure

Abstract

The accurate identification of random dynamic loads under thermal–mechanical coupling is essential for ensuring the structural reliability and safety of aircraft structures. This paper presents a thermally corrected load identification method that integrates power-exponent-weighted regularization with finite element model (FEM) updating. Within the inverse pseudo-excitation framework, the condition number of the frequency response function (FRF) matrix is introduced into the regularization term to adaptively suppress noise amplification in ill-conditioned frequency regions. Meanwhile, thermal experimental modal data are used to update the FEM and reconstruct the FRF under the actual thermal state, reducing the influence of thermal-induced transfer matrix mismatch. Numerical simulation on a wing structure indicates that the proposed method reduces the identification error by 40.7%. Experimental validation further shows an error reduction of at least 24.4%, demonstrating its robustness and applicability for random dynamic load identification in high-temperature aerospace environments.