Combustion and emissions of a direct injection gasoline engine using biofuels

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 (