The Helmholtz Equation Least Squares Method
This book is written for those who want to learn the state-of-the-art technology on visualizing acoustic radiation from vibrating objects, to understand difficulties involved in these inverse acoustic problems, and to acquire the information necessary to conduct successful vibro-acoustic diagnostics on their own. Attention is focused on the new development on nearfield acoustical holography (NAH) beyond the traditional Fourier acoustics that are suitable for separable geometries only. Specifically, it presents:
-Helmholtz equation least squares (HELS) method
-inverse Helmholtz integral equations implemented via boundary element method
- hybrid NAH
- and transient NAH that can be employed to tackle various reconstruction of vibro-acoustic fields generated by arbitrary objects subject to arbitrarily time dependent excitations in free or confined space.
The new technologies discussed in this book have been used successfully by the author and his research group on visualizing acoustic fields and sound transmission paths into an automobile passenger compartment or through door panels of a sedan and truck.
This book can serve both as a textbook for graduate students and as a reference book for acousticians, researchers, and noise control engineers with basic knowledge of acoustics.
Homework problems are included at the end of each chapter. In addition, examples of computer programs written in Matlab are provided for the readers' convenience. This book has been and continues to be designated as the textbook for the graduate level Advanced Acoustics course offered at Wayne State University.
Covers practical aspects of noise and vibration analysis and controlHELS method simplifies the process of reconstructing acoustic fieldsExplains the differences and interrelationships between the Rayleigh series and the HELS method