Impact of multi-mode range and location on fuel economy on a light-duty spark-ignition based powertrain using vehicle system simulations
Advanced compression ignition (ACI) modes have been shown to offer higher brake thermal efficiency than conventional spark ignition combustion with gasoline range fuels. The goal of a full-time ACI in which an ACI mode can be operated in over the entire speed and load map in a conventional passenger vehicle have been limited to date. The benefits of running ACI modes in a portion of the engine operating map have been shown in a number of studies to have potential benefits on improving fuel economy and reducing emissions. An engine that runs in two different combustion modes is known as a multi-mode strategy. Different multi-mode strategies have been proposed and demonstrated in laboratory and in demo vehicle settings.