FLOW PATTERNS AND SOUND GENERATION IN LOW SPEED CAVITIES

Publication Summary

Incompressible LES was coupled with the Lighthill-Curle acoustic analogy expressed in two forms in order to investigate flow patterns and sound generation in open cavities of basic configurations. Previously experimentally observed flow patterns were reproduced. High RMS levels of the transverse velocity were found at the corners of the rear wall with the side walls. Eliminating these corners by using an elliptic cylindrical cavity configuration reduced considerably the RMS levels. Inflow disturbance was found necessary to kick a cavity tone within the time scale of the simulations. The two acoustic predictions showed good agreement and that the dipole noise emitted by the elliptical cavity was lower than in the corresponding box configuration.