IR thermography in heat transfer measurements on a wing leading edge surface internally impinged by a row of air jets

Abstract

The purpose of this work is the investigation of convective heat transfer through a row of circular air jets internally impinging on an airfoil leading edge surface for anti-icing purposes. Measurements are performed with infrared thermography applied to the heated thin foil technique. Tests are carried out by varying: diameter and mutual spacing of jets, impinging distance, Reynolds and Mach numbers. A geometrical calibration of the infrared camera is performed. Data is presented in terms of Nusselt number maps. A new data correlation is proposed between the average Nusselt number and the Reynolds number, by accounting for the impingement angle.