Simulative Estimation of a Super-High-Efficiency Stoichiometric Gasoline Engine with GT-Power

This paper presents a concept of a high efficiency stoichiometric gasoline engine first published in [1]. The engine is modelled in GT-Power and uses the FKFS UserCylinder. All effects and components that cannot be modelled with these two software modules are estimated by tuning the model parameters to achieve the desired effects. The basic concept of the engine for the model was first published in [2] and [3] by Negüs et al. and includes engine friction reduction, improved turbocharger efficiency, variable compression ratio and variable valve train to allow Miller-Cycle and zero-cam profile cylinder deactivation capability. To further increase efficiency of the engine, measures are introduced to increase knock resistance. The first measure includes a pre-chamber spark plug, which proved to significantly reduce combustion duration [4] and thus the likelihood of knock due to rapid combustion of the fuel mass. The second measure is a high-turbulence tumble concept with a switchable tumble flap to further shorten the burn time. The third measure is high-pressure injection [5], feeding fuel close to TDC of the compression stroke. This slows down the pre-knock reactions and further reduces the engine's knock probability. The engine uses an electrically heated three-way catalytic converter and a gasoline particle filter. To make the simulation for the engine comparable, it is integrated into a P0-hybrid-electric powertrain and simulated in a comparative analysis with a low-cost engine for four representative drive cycles.