Sound Intensity and Acoustic Source Quantification to Identify the Noise Contributions of Gasoline Direct Injection Components

In this paper, the sound intensity and airborne source quantification methods were used to estimate the airborne noise radiating from a gasoline direction injection engine and the relative contributions of each of the engine's components to such airborne noise. In order to estimate noise contribution using airborne source quantification, the sound volume velocity for the source should be estimated. In previous methods, the sound volume velocity was estimated using the inverse method, whereas in this paper, the sound volume velocity is estimated directly. For this work, the sources of noise radiating from thegasoline direction injection engine were first identified by measuring the sound intensity of the noise sources while the engine was running idle. The sound volume velocities of these sources were estimated from the product of the area of that noise source and the directly measured particle velocity. In order to validate this method, two speakers with different frequencies were installed in an anechoic chamber and the contribution of each source was estimated. Finally, this proposed method was applied to the identification and contribution of noise sources in a gasoline direction injection engine.