A new method to identify non-steady thermal load based on element differential method

Inverse heat conduction problems (IHCPs) are widely used to identify the thermal load imposed on the components in aerospace fields, and the accuracy and robustness of identification algorithm are the keys to IHCP. In this paper, the element differential method (EDM), Levenberg-Marquardt method (LM) and future time steps method are combined to identify the thermal load. Firstly, the reliability and accuracy of the element differential method are fully verified in solving complex transient heat conduction problems of a variety of temperature-dependent materials. Then, the time-variant temperatures are obtained by the EDM with guessed thermal loads. And complex variable derivative method (CVDM) is used to compute the sensitivity matrix in LM. In addition, the influence of different initial values on the identified thermal loads of the considered 2D and 3D models is also fully analyzed. To prove the robustness of the proposed method, the noises are added to the measured data. Finally, the results show that the proposed method is effective in identifying complex temporal and spatial distributions of heat fluxes, and it shows good accuracy, robustness and noise resistance.& COPY; 2023 Elsevier Ltd. All rights reserved.