Estimation of heat transfer coefficient and heat flux for coupled heat conduction-radiation problem

Inverse coupled heat conduction-radiation problem is a special kind of Inverse Heat Transfer Problem(IHTP)and of significant value in engineering practice.At first,the numerical method for solving the conduction-radiation coupled differential equations are presented and vali-dated in this paper.Secondly,the inversion algorithm to estimate the heat transfer coefficients of thermal conductivity and the absorption coefficient simultaneously,and the algorithm to estimate the unsteady surface heat flux with the conduction-radiation coupling effect taken into account, are developed.And the influences of measurement accuracy,measurement position and absorp-tion coefficient on the estimation result are also investigated.The results show that when the thermal conductivity and the absorption coefficient are estimated simultaneously,the least uncer-tainty in the estimated thermal conductivity is achieved through the measurement point located near the right boundary,while the least discrepancy of the estimated absorption coefficient comes out from the measurement point located in the middle.As for the estimated result of surface heat flux,the nearer the measurement position is to the heated surface,the better the estimation result is.The influence of the absorption coefficient on the estimated result is greater for the measurement point located in the middle compared to measurement points located elsewhere.