Comfortable Sound Design of Diesel Engine Combustion Noise Focused on Sound Pressure Fluctuation in Frequency Bands

Abstract

A new sound improvement method is examined focused on the difference in combustion noise in each cylinder of the diesel engine. First, the impression change of the variation that occurs in each cylinder is grasped by subjective evaluation. Next, sound quality analysis is performed to identify the relationship between the features that represent variations and the sensibilities. In addition, a multiple regression analysis is performed using the evaluation results, and a comfort estimation model for variation among cylinders is constructed. Finally, based on the constructed estimation of a simple model that imitates the cylinder block is changed by computer aided engineering.