Optimization of an Air Intake System to Reduce Multiple Whoosh Noises from an Engine

The direct injection common rail technology coupled with variable geometry turbocharger on the modern diesel engine has improved the diesel engine performance (power and torque) greatly as compared to the conventional diesel engine. Diesel engine performance is greatly dependent on the abundant air availability. And it is facilitated by Variable Geometry Turbocharger (VGT) in modern engines. The engines with variable geometry turbocharger offer quick response to the demand in various driving conditions especially in transient driving conditions. During transient driving conditions, the air intake system experiences a rapid air flow pressure and velocity changes. The pressure differentials across air intake system during transient events allow flow direction changes in the system. This kind of phenomenon generates unusual “Multiple Whoosh” noises in the air intake system of the sport utility vehicle engine. The ‘whoosh’ noise was kind of a noise generated when pressurized air suddenly rushes through a narrow passage. Two to three peaks of such noises were experienced in a very short span of time.

The work presented here describes the approach to reduce multiple whoosh noises from the air intake system of an engine. The engine hardware changes and fine tuning could bring multiple whoosh noises to an acceptable limit.