Abstract
Operational Transfer Path Analysis (OTPA) was successfully applied to noise source contribution analysis especially for diesel engine mechanical noise. At first, as a reference, the crank bearing vibration was divided into the mechanical component and the combustion one which are induced from crank impact and cylinder pressure individually, and then OTPA was applied for detailed separation of mechanical noise out of overall engine noise. The OPTA result was validated by time-consuming experiments with reduced piston system inertia and smaller gear rattle excitation. The validation result showed the good accuracy of OPTA, which indicates its effectiveness to study engine noise reduction.
