Engineering Noise Control

The author gives a comprehensive overview of materials and components for noise control and acoustical comfort. Sound absorbers must meet acoustical and architectural requirements, which fibrous or porous material alone can meet. Basics and applications are demonstrated, with representative examples for spatial acoustics, free-field test facilities and canal linings. Acoustic engineers and construction professionals will find some new basic concepts and tools for developments in order to improve acoustical comfort. Interference absorbers, active resonators and micro-perforated absorbers of different materials and designs complete the list of applications.

This book describes advances in the field of noise control. Chapters present different situations and case studies to better elucidate noise control approaches and applications, including noise mapping and outdoor barriers.

​Caused by downsizing of combustion engines, the torque fluctuation at the crankshaft induces torsional vibrations in the powertrain. Manual transmissions and dual clutch transmissions are particularly sensitive to gear-rattle noise. Gear-rattle noise arises from oscillations of loose parts with clearance, e.g. idler gears, synchronizer rings and gearshift sleeves. The aim of this research is the formulation of a gear oil for the application in a manual transmission to minimize gear rattling noise. Acoustic measurements on a gear-rattle noise test bench verify the noise reduction of the developed gear oils with commonly used low oil viscosity.

This book is written more for the practitioner than the casual reader. Although a high mathematical level is not needed, for much of the material some engineering knowledge is desirable. Noise control is not easy and there are no magic answers to problems. Careful study and patience are required to produce proficiency in the field of noise control.