Development of a feedback model for the self-excited impinging planar jet

Abstract

This article experimentally investigates the self-excited impinging planar jet flow, specifically, the development and propagation of large-scale coherent flow structures convecting between the nozzle lip and the downstream impingement surface. The investigation uses phase-locked PIV measurements and a new structure-tracking scheme to measure convection velocity and characterize the impingement mechanism near the plate in order to develop a new feedback model that can be used to predict the oscillation frequency as a function of flow velocity (Uo), impingement distance (xo) and nozzle thickness (h). The resulting model prediction shows a good agreement with experimental tone frequency data.