An on-line extended Kalman filtering technique for reconstructing the transient heat flux and temperature field in two-dimensional participating media

Accurate measuring of the surface time-dependent heat flux and internal temperature of the participating media is significant in the fields of solar energy and aerospace. In this study, an on-line extended Kalman Filtering (EKF) technique was developed to reconstruct the surface time-varying heat flux and internal temperature field in two dimensions (2D) participating media simultaneously. The forward nonlinear conduction-radiation problem was solved by employing the finite volume method combined with discrete ordinate method. On this basis, the inverse problem for retrieving the surface time-varying heat flux and internal temperature field was solved by the EKF. The performance of the proposed EKF is tested thoroughly by appending different forms of time-varying heat flux on the left surface of the 2D participating media. The effect of medium thickness, time step, measurement noise, process noise, measurement noise covariance, process noise covariance on the stability and accuracy of the reconstructed results are investigated, respectively. All the research outcomes indicate that the time-varying surface heat flux and internal temperature field in the 2D participating medium can be reconstructed accurately and effectively by the EKF technique.