Variable Nozzle Turbine Turbocharger for Gasoline "Miller" Engine

Zero-dimensional turbulence modeling of a spark ignition engine in a Miller cycle « Dethrottling » approach using a variable valve timing system

“…The system can be almost completely modified, as is the case with the MCE-5 engine [8], the crank section can also be redesigned, as the Infinity VC-turbo engine [9], and the connecting rod can vary its stroke while being integrated into the engine without major modifications [10]- [12]. Conventional turbocharger are likely to be equipped with a variable turbine section [13], [14]. The timing and lift of the valves can be modified by different systems during engine operation [15]- [18].…”

Investigation of the Aerodynamic Performance of the Miller Cycle from Transparent Engine Experiments and CFD Simulations

“…Due to over-expansion, the use of the Miller cycle also goes in this direction. Therefore, its application determines a significant improvement of the SI engine's efficiency, but it also allows for a significant drop in the temperature of the exhaust gases to the level where it is even possible to use a classic variable geometry turbine (VGT) with further positive effects on fuel efficiency and drivability [12,13]. For instance, on this matter, the research highlighted in paper [8] showed that the low intake charge associated with the EIVC strategy generates a reduced final compression temperature, which permits the compression ratio (i.e., expansion ratio) to be raised to 12.5:1 without encountering extra NO x emissions or knocking issues and with maximum exhaust temperatures of only 880 • C. Thus, the synergy between the Miller EIVC and VGT was proved.…”