Inverse solution to two-dimensional transient coupled radiation and conduction problems and the application in recovering radiative thermo-physical properties of Si3N4 ceramics

In the present work, a method which combines the discrete ordinate method (DOM), the finite element method (FEM), and the Levenberg-Marquardt (LM) algorithm is proposed to resolve two-dimensional transient inverse coupled radiation and conduction problems. Firstly, three radiative thermo-physical parameters of semi-transparent media are simultaneously retrieved. The effect factors on the results of reconstruction are dis-cussed in detail. Secondly, parameters of Si3N4 ceramics are reconstructed by using experimental measured temperatures as inverse inputs. The results demonstrate that the present method has high accuracy, good sta-bility and robustness. The maximum root mean square deviation of the identified parameters is 4.3%. For the experimental data, the maximum relative error between the reconstructed temperatures and the measurement temperatures is 7.5%. The proposed method could integrate self-made inversion algorithm program and com-mercial software, which is efficient and accurate enough to retrieve thermo-physical properties of semi-transparent media. Moreover, it is convenient for engineering applications.

Automated summary

In this study, a method combining the discrete ordinate method (DOM), the finite element method (FEM), and the Levenberg-Marquardt (LM) algorithm is proposed to solve two-dimensional transient inverse coupled radiation and conduction problems. Firstly, three radiative thermo-physical parameters of semi-transparent media are simultaneously retrieved, and the factors affecting the reconstruction results are discussed in detail. Secondly, the parameters of Si3N4 ceramics are reconstructed using experimental measured temperatures as inverse inputs. The results show that the proposed method has high accuracy, good stability, and robustness.