The Study of Major Noise Sources of a Diesel Engine Using Acoustical Duct Method

The internal combustion engine has mechanized the world. Since the early 1900s, it has become a prime source of mechanical power. In modern times, petrol and diesel engine-powered vehicles find wide application in the field of transport and agriculture. However, the progress has resulted in newer problems. Due to the high density of internal combustion engines, the world over has resulted in the severe pollution problem. They are classified as air and noise pollution. Air pollution is caused due to dispersion of emitted from engine exhaust to the atmosphere at different concentration levels. Similarly, the emission of unwanted sound from engine structure, intake and exhaust are the principal sources of noise pollution. Excessive noise can have severe psychological and physiological effects on human beings like hearing loss, muscular and gastric effects and fatigue.In the present problem, we have studied mechanical-induced noise. Mechanical noise refers to noise generated by the vibrating surface of the engine structure, engine components and engine accessories after excitation by reciprocating or rotary engine components. In mechanical noise, sources are as follows. 1Piston slap2Injection system noise3Timing gear noise4Fuel Injection pump noise5Structure noise6Oil pan noiseIn the present study, we are working on the following two engine sources: 1Fuel Injection Pump2Oil PanThese two noise sources were isolated through wooden ducts for an 80KW diesel engine coupled with a hydraulic dynamo-meter at different speeds and load conditions. The results were compared with the overall sound pressure level (SPL).