Development of a multilayer structure for power unit acoustic shielding
The article presents the theoretical aspects of noise protection device development for the power unit of trucks, as well as the practical research and experimental development of materials for the production of acoustic capsules. The studies of physical-mechanical, heatconducting, sound-absorbing, vibration-absorbing properties of various polyurethane materials were carried out. The prospect of polymeric composite materials use as the acoustic protection of trucks has been revealed.
One of the main problems of modern ecology is the noise pollution of the environment. More and more people feel the negative impact of noise on general health condition. Transport noise, as the main source, prevails in industrial environment . The mechanisms and the systems of vehicle power units are the main source of both external and internal noise of transport. The requirements for the noise of cars throughout the history of vehicles are tightened constantly. Nowadays, the noise of vehicles is normalized by the national standard of Russian Federation GOST R 41.51 (UNECE Regulation No. 51). According to the document, the maximum value of the total noise level is in the range of 74-80 dBA.
Keywords: noise, truck, polyurethane, composite material, sound absorption, thermal conductivity, vibration absorption