Sound Quality Evaluation Method for Engine Combustion Noise with Consideration of Perceived Fluctuation (First Report)

- Quantification of Sound Quality for Combustion Noise in Vehicle Interior during Acceleration -

Abstract

The research discussed in this paper studied a method of quantifying the sound quality of combustion noise identified using a method of extracting the contribution of combustion noise from vehicle interior noise during acceleration in the time domain. Subjective evaluation tests using Scheffe’s paired comparison method were conducted, involving the presentation of multiple types of combustion noise to 14 NVH development experts via a headphone-playback system. Based on the results of subjective evaluation tests, fluctuation intensity, a psychoacoustic metric, was employed in the development of the dissonant combustion noise index (DCNI) as a new objective evaluative index for the sound quality of combustion noise. A new technique that couples the method of extraction of the contribution of combustion noise in the time domain with the new index DCNI was used to analyze the combustion noise of Japanese Kei small car models, and the results demonstrated that the technique is able to provide an accurate quantitative grasp of the relative sound quality of combustion noise.