Eventos Anais de eventos
COBEM 2019
25th International Congress of Mechanical Engineering
Aeroacoustics experiments on circular cylinder near plane wall.
Submission Author:
Matheus Maia Beraldo , SP
Co-Authors:
Matheus Maia Beraldo, Christian Bresci, Filipe Amaral, Juan Carlos Serrano Rico, Marcello Augusto Faraco de Medeiros
Presenter: Marcello Augusto Faraco de Medeiros
doi://10.26678/ABCM.COBEM2019.COB2019-1564
Abstract
A concept of aeroacoustic noise is the sound generated by the flow when passing over a body regardless of the geometry. This work aims to study the noise of a cylinder and the influence of the proximity of a plane wall with laminar boundary layer. The study took place at the LANT wind tunnel at EESC-USP. Acoustic measurements and acoustic source maps were performed using a microphone array with beamforming technique and DAMAS deconvolution method. A flat plate model and a wire were mounted in the test chamber and the distance between the wire and the model was varied by bringing it close to the plate in order to vary the Gap / Diameter. Measurements with Hot-wire anemometer at the flat plate show that in all cases the boundary layer was laminar. The results show that the sound generated by the cylinder presents tonal peaks arising in frequencies relative to number of Strouhal around 0.19. Maps of acoustic source finding the sources on the wire attached to the test chamber. It was shown that when the cylinder is closest to the plate, about G / D = 4 there is a suppression in the generated noise and a large drop in the intensity of the tones generated by the presence of the wire.
Keywords
Experimental Aeroacustics, conventional beamforming, DAMAS, Cylinder noise
