Noise Propagation of 6 hp Farm Diesel Engine

Abstract

Considering the undesirable effects of noise and long working hours of farm workers, a study was conducted to investigate noise propagation of a commonly used 6 hp farm diesel engine in operator’s workspace. Height of muffler from ground was 0.9 m and direction of water discharge pipe was towards right w.r.t muffler opening. Measurements of sound pressure level (SPL) was made in three vertical planes viz. at height equal to engine muffler, 0.5 m above and 0.5 m below. In each vertical plane, five horizontal radial distances of 0.5, 1.0, 1.5, 2.0, and 2.5 m were taken. The direction of muffler opening was taken as 0° and it increased in anticlockwise direction. A total of eight angles with increment of 45° were taken for direction of measurement in a given vertical plane. The mean SPL at muffler opening of diesel engine was 120.9 dB. Mean SPL varied from 71.2 to 99.4 dB among all the treatments. SPL decreased with the change in angle from 0° to 180° for both clockwise and anti-clockwise directions. SPL towards right side of muffler opening was comparatively higher because of noise generated by irrigation water. Considering the results obtained, the findings can be extended for possible use in tractor operator’s workspace. It was concluded that operator’s seat should be located at a maximum possible radial distance from the muffler. The muffler opening should be in the opposite direction w.r.t. the operator’s seat.