Abstract
Previously the authors developed the dissonant combustion noise index (DCNI), which is an objective evaluation index for combustion noise quality in vehicle interiors. At present, the DCNI is used effectively in actual mass-production vehicle developments. However, the DCNI was developed based on the results of subjective evaluation experiments conducted by 14 experts in engine vibration and noise, hence it is pointed out that its effectiveness for the feeling of general vehicle users has not been verified. Therefore, subjective evaluation experiments of combustion noise were conducted based on Scheffe's paired comparison method. A total of 19 experts and 200 non-experts (general vehicle users) evaluated 15 different combustion noise in three different speed conditions using a headphone playback system. The results demonstrated that the DCNI is appropriate as an objective evaluation index to enhance engine sound quality in vehicle interiors.
