Research of tractor noise at acceleration mode

The article presents results of research of tractor noise propagated to environment from tractor working in acceleration mode, comparison these results with the tractor working in steady mode and at the end of acceleration mode and also theoretical and analytical calculation possibility of variation of the tractor noise character during the acceleration mode. Tests showed that equivalent noise level LA, eq at tractor acceleration mode varied in the limits of 3-7,5 dBA and reached 91... 95 dBA level. When tractor was working at steady mode before acceleration, LA,eq ranged in 86,3...87 dBA whereas during and after acceleration LA, eq ranged in 90...95 dBA. For lower power tractors, with smaller air-cooled engines, noise level was defined respectively 94,6; 95,6 and 95,1 dBA. The maximum noise level variation at acceleration mode was fixed for 14kN pull force tractors with diesel engines without turbochargers. Analytical method determined that variation of characteristics of noise level from accelerating tractors mostly depend on engine crankshaft rotation speed, torque and clutch switching timeVytauto Didžiojo universitetasŽemės ūkio akademij