Real-time particle image velocimetry for closed-loop flow control applications

Abstract

Particle image velocimetry (PIV) has been a standard laboratory technique in experimental fluid mechanics for many years, allowing quantitative visualization of fluid flows. Typically, the particle images are captured and then are subsequently subjected to image processing to eventually yield vector fields. In this paper, we describe a system that allows for "real-time" processing of the image pairs followed by post-processing to immediately provide fluid mechanical quantities not accessible with conventional point wise measurement techniques. In effect the real-time flow field data acts as a sensor in a flow control experiment. This paper will discuss the design, implementation and performance of the system as it applies to control of vortex formation processes on a low Reynolds number airfoil inside an oil tunnel facility.