Avaliação das fontes de ruído em tratores agrícolas.

Abstract

This work had as objective the identification and spectral analysis of the noise sources in agricultural tractors. Innumerable scientific works have been evaluating the high noise levels emitted by those machines, that usually exceed the 95 dB(A), placing in risk the audition of your operators. The identification of the mechanisms of the tractor that generate noise is of great importance for the researchers, because it allows the attenuation project or elimination of the noise. The methodology used in the evaluation it consisted of sound spectrum analyzing of the tractor main sources of noise being used a data acquisition system (analogical-digital board installed in a computer) for the frequency spectrum drawing. The results showed that the total noise of a tractor is formed by the composition of the engine gases exaust noise, helix noise, inject pump noise, air filter noise and engine mechanical vibration noise. The quantification of each noise portion is presented in spectral curves. As conclusion, is possible to notice the importance of the identification of each source of tractor noise, mainly with the spectral analysis. These data allow to quantify the fractions that form the total noise, facilitating plenty the attenuation work of the noise in each source.