Combustion Noise

​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.

Free Field Technologies, the Belgium arm of MSC Software that is now part of Hexagon Manufacturing Intelligence, a global engineering software company, announced the Actran 2020 design and simulation software suite comprising new acoustic, vibro-acoustic and aero-acoustic technologies that enable manufacturers to build more accurate noise prediction models of their designs, with optimizations into their processes.

This book discusses all aspects of advanced engine technologies, and describes the role of alternative fuels and solution-based modeling studies in meeting the increasingly higher standards of the automotive industry. By promoting research into more efficient and environment-friendly combustion technologies, it helps enable researchers to develop higher-power engines with lower fuel consumption, emissions, and noise levels.