Particulate emissions from a highly boosted gasoline direct injection engine

Andrew Lewis, Sam Akehurst, James Turner, Felix Leach, Richard Stone, Dave Richardson, Sarah Remmert, Roger Cracknell, Steven Campbell

Research output: Contribution to journalArticle

13 Citations (Scopus)


Downsized, highly boosted, gasoline direct injection engines are becoming the preferred gasoline engine technology to ensure that increasingly stringent fuel economy and emissions legislation are met. The Ultraboost project engine is a 2.0-L in-line four-cylinder prototype engine, designed to have the same performance as a 5.0-L V8 naturally aspirated engine but with reduced fuel consumption. It is important to examine particle number emissions from such extremely highly boosted engines to ensure that they are capable of meeting current and future emissions legislation. The effect of such high boosting on particle number emissions is reported in this article for a variety of operating points and engine operating parameters. The effect of engine load, air–fuel ratio, fuel injection pressure, fuel injection timing, ignition timing, inlet air temperature, exhaust gas recirculation level, and exhaust back pressure has been investigated. It is shown that particle number emissions increase with increase in cooled, external exhaust gas recirculation and engine load, and decrease with increase in fuel injection pressure and inlet air temperature. Particle number emissions are shown to fall with increased exhaust back pressure, a key parameter for highly boosted engines. The effects of these parameters on the particle size distributions from the engine have also been evaluated. Significant changes to the particle size spectrum emitted from the engine are seen depending on the engine operating point. Operating points with a bias towards very small particle sizes were noted.
Original languageEnglish
Pages (from-to)347-359
Number of pages13
JournalInternational Journal of Engine Research
Issue number3
Early online date29 Jun 2017
Publication statusPublished - 1 Mar 2018



  • Gasoline direct injection
  • Ultraboost
  • boosting
  • downsizing
  • particle number
  • particulate

ASJC Scopus subject areas

  • Automotive Engineering
  • Aerospace Engineering
  • Ocean Engineering
  • Mechanical Engineering

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