Retrieval of geometric structure of internal defect in two-dimensional semi-transparent media under laser irradiation using the RDS-PSO

In present study, the inverse problem of reconstructing the internal defect in two-dimensional (2-D) laser irradiated semi-transparent media has been studied thoroughly. Considering the natural convection boundary, the transient coupled conduction-radiation heat transfer in 2-D semi-transparent media under laser irradiation has been solved by the Finite Volume Method (FVM) as the forward problem. Taking the ZrO₂ ceramic media with defects as an example, the sensitivity of rectangular defect, circular defect and the convective coefficient of surrounding air to the excess temperature distribution at boundaries has been investigated, respectively. Based on the sensitivity analysis, a Random Direction Search Particle Swarm Optimization (RDS-PSO) algorithm was adopted to retrieve the geometric parameter of two different shape (rectangular and circular) defects in the 2-D media. The objective function is expressed by the sum of square errors between estimated and measured transient temperature profiles on the boundary. All the results show that the size locations of the internal defects can be reconstructed reasonably by the RDS-PSO.