Exploring a Gasoline Compression Ignition (GCI) Engine Concept

<div class="section abstract"><div class="htmlview paragraph">Future vehicles will increasingly be required to improve their efficiency, reduce both regulated and CO₂ emissions, and maintain acceptable levels of driving, safety, and noise performance. To achieve this high level of performance, they will be configured with more advanced hardware, sensors, and control technologies that will also enable their operation on a broader range of fuel properties. These capabilities offer the potential to design future vehicles to operate on the most widely available and GHG-reducing fuels.</div><div class="htmlview paragraph">In previous studies, fuel flexibility has been demonstrated on a compression ignition bench engine and vehicle equipped with an advanced engine management system, closed-loop combustion control, and air-path control strategies. An unresolved question is whether engines of this sort can operate routinely on market gasoline while achieving diesel-like efficiency and acceptable emissions and noise levels.</div><div class="htmlview paragraph">This paper describes initial engineering and experimental steps to assess this potential. Using an advanced diesel bench engine having a higher compression ratio, optimized valve timing, and flexible fuel injection, the engine could be operated on a European market gasoline over full to medium part loads. The combustion was found to be highly sensitive to EGR rates, however, and the simultaneous optimization of all regulated emissions and combustion noise was a considerable challenge. An advanced glow plug was tested to improve low load performance but did not extend the engine operating range as much as expected.</div></div>