Improved teaching-learning-based optimization for estimation of temperature-dependent radiative properties of semitransparent media

Inverse estimation of temperature-dependent refractive index and absorption coefficient of semitransparent media is studied in this work. The forward transient coupled radiation-conduction heat transfer in semitransparent media is simulated by the finite volume method. The time-varying radiative response signals at the boundary (not the laser irradiation boundary) is adopted as measurement information in the inverse model. An improved teaching-learning-based optimization (ITLBO) algorithm is developed to retrieve the temperature-dependent refractive index and absorption coefficient simultaneously. Effects of model parameters (i.e. the laser heating time and measurement errors) and thermophysical parameters (i.e. the thermal conductivity and heat capacity) on the estimated results are analyzed thoroughly. All the retrieval results show that the inverse model and inverse algorithm is accurate and effective for predicting the temperature-dependent radiative properties of semitransparent media.