Inverse estimation of heat flux from a hollow cylinder in cross-flow of air

The heat flux at the surface of an initially heated cylinder under the cross-flow of air has been investigated. The aim is to propose an inverse heat conduction method to avoid expensive measuring processes or that eliminates difficulties in direct measurements such as applying the sensors directly to the surface which may either burn it or affects the flow field. In addition, to develop empirical correlations to predict local and average heat transfer from a cylinder under subcritical range of Reynolds number 1.1 × 104 ⩽ Re ⩽ 6.2 × 104. The inverse method makes use of Levenberg-Marquardt approach for parametric estimation to determine the surface heat flux. It requires the computation of sensitivity matrix, which has been computed by using the Duhamel's theorem. An analysis of heat transfer data obtained from the proposed inverse method and the predictions from the developed empirical correlations revealed an average deviation of less than 1% compared to reported literatures.