Fundamental investigation of the flow around a finite span low aspect ratio pin and its application to flow control

Abstract

A separate study was conducted to evaluate the global impacts from the low aspect ratio pins over a deflected control surface of a NACA 0012 airfoil as a potential means of separation control using SPIV and surface pressure measurements. An array of pins, fully submerged within a turbulent flow, and placed upstream of a strong adverse pressure gradient and severely separated flow, demonstrated significant reduction in separation and total drag, while increasing the global circulation (i.e., lift). Most notably, the influences from a single static pin were compared to that of a dynamic pin and results indicated an ability to lock on and amplify the shedding frequency associated with the wake of the airfoil. These results provide further evidence of the potential uses for low aspect ratio pins (static or dynamic) as effective devices for a wide-range of applications, and more specifically, for separation control.