Abstract
PCI (Premixed Compression Ignition) combustion is a potential breakthrough technique to simultaneously reduce NOx and particulate matter in engine exhaust emissions. A noise survey was conducted to identify the following noise attributes: 1) engine noise level and 2) sound quality of an engine operated under PCI combustion. The results show that PCI combustion is capable of achieving the same or lower noise level than with conventional combustion operated with pilot injection. In addition, PCI combustion was quantitatively evaluated as having better sound quality than conventional combustion because it contains less high-frequency components in engine noise.
