Throttleless and EGR-controlled stoichiometric combustion in a diesel–gasoline dual-fuel compression ignition engine

Research output: Contribution to journalArticlepeer-review

Authors

Colleges, School and Institutes

Abstract

Stoichiometric Diesel and Gasoline Dual-fuel (Dieseline) Compression Ignition (SDCI) combustion using three-way catalyst (TWC) after-treatment is a promising technology to address the challenge issues of fuel consumption and emissions in future internal combustion engines. The authors use EGR instead of the throttle to control the load of the dual fuel compression ignition combustion engine. In order to investigate the fuel consumption and emission characteristics of SDCI combustion, a series of experiments were conducted in a modified single cylinder diesel engine using gasoline with a small portion of diesel for ignition enhancement. The experimental results show that SDCI combustion can achieve high indicated thermal efficiencies in a relatively wide range of loads (IMEP 4.3–8.0 bar) because of a higher compression ratio, shorter combustion and smaller pumping losses. An attractive indicative specific fuel consumption (ISFC) of 190.8 g/kW h has been achieved at a medium load without any boosting and the PM emissions are lower than for conventional diesel combustion. Different diesel percentages in the dual fuel supply have shown a significant impact on the ignition process and provide a wider available time range for combustion phase control. Diesel direct injection (DI) timing has a greater effect on PM emissions than the fuel ratio. Late DI timing reduces the thermal efficiency and results in higher PM emissions. Early DI timing and less diesel are preferable in order to reduce or avoid the diffusion combustion stage, which may lead to high PM emissions in the stoichiometric combustion.

Details

Original languageEnglish
Pages (from-to)765-777
JournalFuel
Volume115
Early online date31 Jul 2013
Publication statusPublished - Jan 2014

Keywords

  • Dual fuel, Dieseline, Stoichiometric combustion, EGR, PM