Combustion and emissions of a direct injection gasoline engine using biofuels

[摘要] Impact of biofuel (2-methlyfuran, 2,5-dimethylfuran and ethanol) on the performance of a gasoline direct injection engine has been investigated. MF demonstrates better knock resistance properties and faster burning rates compared to those of gasoline. MF has much lower fuel consumptions than ethanol, produces much lower hydrocarbon (HC) and PM emissions than those of gasoline. However NOx emissions from MF are significantly higher than those of gasoline when fuel-optimized spark timings are used, which can be addressed by either retarding ignition timing or using exhaust gas recirculation. MF produce much lower aldehyde emissions compared with gasoline, methanol and ethanol. The majority of HC emissions are unburned fuel. Toluene and benzene are detected in the exhaust however their concentrations are relatively low. Under rich combustion and later injection operating conditions, soot only accounts for a small fraction (<30%) of PM. Soot produced from the combustion of DMF and ethanol is more easily oxidized than gasoline soot due to their unique capsule type oxidation mode, smaller primary and agglomerated particles. PM emissions vary significantly to fuel and injection system. Unlike gasoline, PM emissions from ethanol powered the DISI engine are not sensitive to injection system; a low injector pressure and a bad injector condition have very limited negative impacts on PM emissions.

[发布机构] University:University of Birmingham;Department:School of Engineering, Department of Mechanical Engineering

[关键词] T Technology;TJ Mechanical engineering and machinery