Integration of a Small On-Board Reformer to a Conventional Gasoline Internal Combustion Engine System to Enable a Practical and Robust Nearly-Zero Emission Vehicle

摘要

Small amounts of supplemental hydrogen fuel have been shown to allow conventional gasoline internal combustion engines to reach nearly zero emissions levels. A continual progress has been made in developing an integrated Engine Management System (EMS), which includes partial fueling with gasoline reformate. This is a promising approach to robustly meet the Super Ultra Low Emission Vehicle (SULEV) proposals contained in the ULEV II regulations for California ― even for relatively large and heavy vehicles ―without forcing a change to the fuel infrastructure. This paper presents the low emission potential of the on-board reformer strategy for both an essentially zero emission cold start and for improved warmed-up emissions and robustness. It continues with data on the efficiency potential of ultra-lean burn operation with low NOx emissions - compared to the Euro 4 and SULEV requirements. It concludes with discussion of on-board reforming methods, highlighting the need for an instant-on reformer to meet nearly-zero start-up emissions and a very efficient reformer to meet the requirements of increased fuel efficiency and extremely low warmed-up NOx emissions.