IDENTIFICATION AND RANKING OF NOISE SOURCES IN A THREE WHEELER

Abstract

The aim of the investigation is to, identify and consequently rank the major noise sources in a petrol driven three wheeler. The major noise sources of the vehicle studied were 1) Engine noise; 2) Transmission noise; 3) Cooling fan noise; 4) Exhaust noise; 5) Intake noise. The noise measurement were made running the engine at a constant speed and power in two transmission ratios viz. the 3rd and 4th gears, to identify the effect of transmission ratio on the sound power output. Such a condition would typically simulate a fully laden vehicle running at near top speed in these gears. It has been observed that among the mechanical noise sources, the engine and transmission are most important and among the aerodynamic noise sources the cooling fan and the 1. exhaust are most important.