Structure-borne sound

• explain the fundamental mechanisms and phenomena which generate vibration and sound waves in solid media and structures
• conduct calculations and analyses of the dynamic properties of simple resonant systems
• derive equation of motion for simple resonators and explain frequency responses and determination of damping properties, eg. from Nyquist diagram
• explain/evaluate wave phenomena for longitudinal waves and bending wave fields in beams and rods and calculate vibrational responses
• demonstrate the use of mobility methods for calculating response of built-up systems
• conduct and report on vibro-acoustic measurements, including applied signal analysis (spectral analysis, estimation of transfer functions, structural damping properties, etc.)
• explain principle of vibration isolation and calculate insertion loss of simple vibration isolated sources
• explain reasons for losses in structures and principles for added damping and calculate damping of single-layer viscoelastic vibration damping
• evaluate reflection and attenuation of structureborne waves in built-up systems, including periodic structures
• explain and calculate wave fields and propagation of bending waves in plates
• apply Statistical Energy Analysis and Matlab-based finite element analysis for calculating vibration in systems
• explain and calculate sound radiation from compact simple sources and from plate-like structures, cabinets and cylinders

Mechanisms for the generation of vibration and sound in structures. Simple resonators and models for damping mechanisms. Concepts of mobility and mechanical impedance. Vibro-acoustic measurement techniques. Introduction to applied signal analysis (spectral analysis, estimation of transfer functions, etc). The generation of vibration and sound waves in solids and structures (structureborne sound). Longitudinal waves and bending waves in beams and plates. Analytical and statistical methods for calculating structureborne sound and transmission in complex structures. Vibration isolation, attenuation and damping of structureborne sound in equipment and machinery. Sound radiation from vibrating structures (plates, cylinders, cabinets, etc). Control and damping of vibration and sound radiation. Principles for altering the transmission and radiation properties of structures.

31200/31241/34840/34844

Lectures, compulsary mini-projects and experimental excercises, problem solving and review of written exercises.

The course is aimed at students who, having followed a basic course in acoustics, wish for a more advanced understanding of sound and vibration, its generation, propagation and attenuation. The course is a natural introduction to a master thesis work in Acoustic Technology and/or CAMM – Centre for Acoustic-Mechanical Microsystems. It is good to have taken 31240 and 31260 beforehand.

E-learning is used in the form of video streamed podcast lectures, quizzes etc, and digital exam.