Acoustic Analyses Using Matlab® and Ansys®

This is the first book of its kind that describes the use of ANSYS® finite element analysis (FEA) software, and MATLAB® engineering programming software to solve acoustic problems. It covers simple text book problems, such as determining the natural frequencies of a duct, to progressively more complex problems that can only be solved using FEA software, such as acoustic absorption and fluid-structure-interaction. It also presents benchmark cases that can be used as starting points for analysis. There are practical hints too for using ANSYS software. The material describes how to solve numerous problems theoretically, and how to obtain solutions from the theory using MATLAB engineering software, as well as analyzing the same problem using ANSYS Workbench and ANSYS Mechanical APDL. Free downloads are provided on http://www.mecheng.adelaide.edu.au/avc/software, including MATLAB source code, ANSYS APDL models, and ANSYS Workbench models Includes readers’ techniques and tips for new and experienced users of ANSYS software Identifies bugs and deficiencies to help practitioners avoid making mistakes It can be used as a textbook for graduate students in acoustics, vibration, and related areas in engineering; undergraduates in mechanical and electrical engineering; and as an authoritative reference for industry professionals.

Introduction About This Book A Philosophy for Finite Element Modelling Analysis Types Background Learning Outcomes Introduction Pressure Formulated Acoustic Elements Fluid Structure Interaction Displacement Formulated Acoustic Elements Practical Aspects of Modelling Acoustic Systems with FEA Element Types in ANSYS for Acoustic Analyses ACT Acoustics Extension Other Acoustic Loads Other Measures of Acoustic Energy Mesh Density Use of Symmetry Ducts Learning Outcomes Theory Example of a Circular Duct Resonator Silencers Non-Plane Waves Gas Temperature Variations Sound Inside a Rigid-Walled Cavity Learning Outcomes Description of the System Theory Example Introduction to Damped Acoustic Systems Learning Outcomes Introduction General Discussion of Damping of Vibro-Acoustic Systems in ANSYS Theory Example: 2D Impedance Tube with a Real Admittance Example: 2D Impedance Tube with a Complex Termination Impedance Example: 2D Impedance Tube Example: 3D Impedance Tube Example: 3D Waveguide with Visco-Thermal Losses Application of Spectral Damping to a Rigid Walled Cavity Sound Absorption in a Lined Duct Learning Outcomes Definitions Description of the System Theory Example - Locally Reacting Liner Example - Bulk Reacting Liner Room Acoustics Learning Outcomes Description of the System Theory Example: Reverberation Room Radiation and Scattering Learning Outcomes Wave Absorbing Conditions Example: Directivity of Acoustic Wave Sources Example: Radiation of a Baffled Piston Scattering Example: Scattering from a Cylinder Fluid Structure Interaction Learning Outcomes Fluid Structure Interaction Using ANSYS FSI Using Modal Coupling Example: Flexible Plate Attached to an Acoustic Cavity Example: Transmission Loss of a Simply Supported Panel A. Files Included With This Book B. Advice for Using ANSYS C. MATLAB Functions for Modal Coupling D. Errors E. Export of Nodal Area from ANSYS Bibliography Index

Dr. Carl Howard is a Lecturer at the University of Adelaide. He has been a consultant with Vipac Engineers and Scientists, Worley, and Colin Gordon and Associates, and also worked at United Technologies Research Center. Dr Ben Cazzolato is an Associate Professor at the University of Adelaide. He has over two decades' experience as an acoustic consultant and academic researcher.