INVERSE CALCULATION OF FLAME IMPINGEMENT HEAT TRANSFER

Inverse calculations are presented here for the estimation of heat transfer from an impinging flame on a flat surface. This work is a preliminary exercise for estimating heat transfer from an impinging plasma jet, where direct measurements can be very difficult and costly, and the correlations based on air or water jet impingement measurements may not be applicable because of the very high temperature (and property) gradients. As the gas flame impinges on an initially cold flat plate, the temperature evolution on the backside is recorded using an infrared camera. The time-temperature data thus obtained are then compared with those predicted by a finite volume method based code. The code uses a polynomial series for estimating the convection coefficient, which varies with radial distance. The coefficients of this polynomial are treated as a set of parameters to be estimated through the Levenberg-Marquardt approach. The results obtained so far indicate that it may be possible to use such an approach for estimating heat transfer from a plasma jet.