Research on the reconstruction of the vibro-acoustic field generated by the complicated sources using the modified wave superposition algorithm

Abstract

The nearfield acoustic holography (NAH) method based on the wave superposition algorithm (WSA) assumes that the sound field is induced by a series of simple sources inside the vibrational object boundary. The sound field can be reconstructed after the strength of virtual sources is determined in an inverse procedure. The theory, numerical simulation, and application of WSA-based NAH is often concerned with the simple sources. In practice, the vibrational objects are more complicated and sometimes should even be treated as multiple separated objects. The reconstruction of a sound field by using conventional WSA-based NAH directly is not satisfactory. In the presented modified WSA-based NAH, complicated vibrational objects are separated into several parts and looked at as independent components. Whole sound fields are generated by all these components. The comparisons between conventional and modified WSA-based NAH are carried out through numerical simulations. It shows that the more accurate result is obtained by applying the modified WSA-based NAH to the complicated objects. An experiment of a compressor with complicated structures is conducted to illustrate the validity of modified WSA-based NAH.