Inverse-Imaging Method for Detection of a Vortex in a Channel

A simple vortex-imaging algorithm using a least-square method is considered. The position and the circulation of a vortex convected in a channel are identiŽ ed from the time history of pressure at a limited number of points on the wall. The capabilities of the algorithm are demonstrated using two-dimensional direct numerical simulations. A few observer points on one side of the wall are sufŽ cient to detect the position and the circulation of a compact vortex to a reasonable degree of accuracy. An advanced algorithm can even detect two nearby vortices to the same degree of accuracy. Because the algorithm assumes a point vortex solution, the accuracy of the detection deteriorates as the vorticity distribution spreads.