Turbulent impingement jet heat transfer on concave surfaces for aeronautical applications

Abstract

Turbulent impingement jet heat transfer on concave surfaces has been employed in different engineering applications, e.g., aviation industry. In the aircraft anti-icing systems, hot air from the engine compressor impinges on the inside surface of the leading edge through small drilled holes, configuring the so-called piccolo tube system. A critical aspect in the design of such system is the prediction of heat transfer impinging jets from the piccolo tube. The correct evaluation of the heat transfer rate in such devices is of great interest to optimize both the anti-icing performance and the hot-air bleeding from the high-pressure compressor. Therefore, the present study develops a parametric study of the impingement jet flow on concave surfaces employing the CFD tool. The main goal is to determine the effect of the jet Mach number on this heat transfer mechanism. The present results also showed that at lower H/d conditions, i.e., lower jet-to-impinging surface distances, the temperature field exhibits a more efficient heating process inside the domain, resulting in greater Nusselt number values. A correlation taking into account geometric parameters such as the jet-to-jet spacing and the jet-to-impinging surface distance and jet Mach number is also proposed.