Gasoline Water Direct Injection(GWDI)as a Key Feature for Future Gasoline Engines

摘要

Water injection into internal combustion engines has long been known as a powerful tool to increase either maximum power and/or decrease emissions. Up to now, product costs and application effort have prevented a broad serial introduction of this technology. Competition with electric drive technology and tighter emission legislation make this feature more attractive for serial application in gasoline engines. Therefore, the different benefits of water injection are evaluated in this paper. The direct injection of water into the combustion chamber is realized through the use of an emulsion with a variable water-fuel ratio. Gasoline water direct injection(GWDI)results are contrasted with data obtained by water injection into the intake pipe after the intercooler. Furthermore,investigations regarding knock limited combustion and mitigation of fuel enrichment were performed on two engines from different OEMs, both with turbocharging and direct injection. The study is completed by a detailed testing of the impact of water injection on stochastic(low speed)pre-ignitions(SPI).