Application of holography in jet acoustic studies

Source strength distribution on a jet. boundary was obtained from measurements using the principle of acoustic holography. Measurements were conducted in an open field. Measurement of acoustic pressure on a cylindrical two-dimensional contour located close to the vibrating jet boundary was used to obtain the acoustic source strength distribution at the jet boundary. Particular attention was focussed on back projection of the sound field on to a cylindrical surface. A jet emanating from 5 mm convergent nozzle was used for the holography experiments, assuming axisymmetry. Experimental results were compared with results obtained from holography.