Engine Parameters Assessment for Alcohols Fuels Application in Compression Ignition Engines

An increasing interest of governments on alternative fuels for internal combustion engines (ICE) as a possible route to reduce pollutant and CO2 emissions has been shown. Advanced combustion concepts combined with alternative fuels have the potential to improve efficiency and emissions levels. In this framework, the compression ignition (CI) engines have a higher brake thermal efficiency compared to the spark ignition (SI) engines and therefore lower efficiency related CO2 emissions. High research octane number (RON) fuels can be used in CI engines to realize premixed combustion thus reducing the soot emissions, and to a certain extent also NOx. Thus, alternative alcohol fuels such as methanol and ethanol represent a valuable option for further reducing the CO2 footprint of CI engines. In this chapter, the main advantages and drawbacks of using alcohols as primary fuel or additive in diesel are evaluated in terms of performance, combustion characteristics and emissions, with particular reference to energetic analysis.