ASA 124th Meeting New Orleans 1992 October

2pSA4. Holographic reconstruction of the acoustic intensity from measurements over a limited surface.

Angie Sarkissian

Naval Res. Lab., Washington, DC 20375-5000

The normal component of the acoustic intensity on the surface of a radiating structure is reconstructed from pressure values over a limited region of space. The small measurement surface that is located very close to the structure enables a high resolution reconstruction of the surface pressure and the surface normal velocity over a small region on the structure surface located just below the measurement surface, from which the normal component of the acoustic intensity is computed. The reconstructed intensity in the region below the measurement surface compares favorably to the intensity reconstructed from a measurement surface surrounding the entire structure. The algorithm is developed by applying the boundary-element method to compute operators relating the surface pressure and the measured pressure to the surface normal velocity with the latter operator inverted by applying singular value decomposition.