Technical Paper
Investigation to Leveraging Effect of Ethanol Direct Injection (EDI) in a Gasoline Port Injection (GPI) Engine
2013-04-08
2013-01-1322
Ethanol has been used either as an alternative fuel or in blends with gasoline in spark ignition (SI) engines for many years. However, the existing method of using ethanol fuel by blending gasoline and ethanol fuel does not fully exploit the ethanol fuel's potential in improving engine thermal efficiency and reducing pollutant emissions. The dual-fuel injection strategy, ethanol direct injection plus gasoline port injection (EDI+GPI), offers a potentially new way to make the best use of ethanol fuel. In this paper the potential of EDI+GPI is investigated based on experiments conducted on a single cylinder SI research engine equipped with EDI+GPI. The leveraging effect of EDI+GPI on engine performance was investigated at different ethanol/gasoline energy ratios (EERs) and speeds. Then further investigation to the leveraging effect enhanced by ethanol injection timing and spark timing was performed. Experimental results showed that the IMEP increased with the increase of EER.