Diluted Operation of a Heavy-Duty Natural-gas Engine

摘要: Fuel economy and emissions are the two central parameters in heavy duty engines; most of existing engines run with diesel. The overall efficiency diesel is good however they suffer from high levels mainly NOX soot. Using alternative fuels like Natural-Gas has shown to be a way reduce level. Diesel can easily converted which very cost effective for producing engines. High EGR rates combined turbocharging been identified as promising increase maximum load spark ignition With stoichiometric conditions three catalyst used means that regulated kept at low levels. However efficiencies lower than corresponding versions due throttling losses. These losses higher low/part loads. loads efficiency; obtaining reliable difficult pressure dilution. There limit amount tolerated each operating point. A combustion stability parameter should indicate tolerance engine. Different derived ion-current signals applied order control dilution EGR. Furthermore closed-loop lambda air/fuel ratio. help these controllers also controller, tool developed finding best positions throttle valve where engine its highest while preserved. Two papers written based on results this study i.e. first one second signals. proposed strategy successfully tested 6-cylinder port-injected natural-gas show 1.5-2.5 % units improvement Brake Efficiency. In another experiment, behaviour was investigated by running Hythane (Natural gas + 10% Hydrogen ) when operates stoichiometric. Data lean burn available it desired see behavior operation. do not significant changes knock margins, However, Lean extended somewhat Hythane.