Experiments and Computations on the Lift of Accelerating Flat Plates at Incidence

This paper discusses the force history and flow topology of accelerating flat-plate wings. The work is a collaborative effort to study fundamental, unsteady low-Reynolds-number flows. The motion kinematics is designed to be relevant to the micro air vehicle flight regime. A combination of experimental and computational techniques is used to obtain data for comparison. There is a striking correlation of lift history data and flow topology from both experimental and computational data sets. It is found that the leading/trailing-edge vortex core separation during the initial part of a surge motion can be reasonably well approximated by c⋅cosα, , and the leading/trailing-edge vortex relative advection velocity is estimated to be 0.5⋅U∞. This leading/trailing-edge vortex relative advection velocity is a useful measure of how quickly the trailing-edge vortex moves away from the leading-edge vortex, which can influence lift for accelerating flat plates at high incidence angles.R. J. Bomphrey and N. Phillips were supported by the Engineering and Physical Sciences Research Council (EP/H004025/1 to R. J. Bomphrey). R. J. Bomphrey and T. Nakata were supported by the Biotechnology and Biological Sciences Research Council (BB/J001244/1 to R. J. Bomphrey)

Low Reynolds number acceleration of flat plate wings at high incidence (Invited)

This paper discusses the force history and flow topology of accelerating flat plate wings. The work is a collaborative effort to study fundamental, unsteady low Reynolds number flows under the umbrella of the NATO AVT-202 task group. The motion kinematics are designed to be relevant to the Micro-Air Vehicle (MAV) flight regime. A combination of empirical and computational techniques are used to obtain data for comparison. There is a striking correlation of lift history data and flow topology from both experimental and computational datasets. In an effort to source inputs for a low-order model, a Leading Edge Vortex (LEV)/Trailing Edge Vortex (TEV) relative advection velocity of 0:5.U∞ has been estimated based on the data