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As boosted, direct injected gasoline engines become more prevalent in the automotive market, the boosting system architecture and efficiency are intimately entwined with the efficiency and performance of the engine. Single-stage as well as two-stage boosting systems, comprising of either two turbochargers or a supercharger in combination with a turbocharger, are potential configurations. When combining an internal combustion engine with boosting hardware, a mechanical, fluid-dynamic and thermodynamic coupling is created and the system as a whole will need to be treated as such.

Dedicated EGR (D-EGR) is an EGR strategy that uses in-cylinder reformation to improve fuel economy and reduce emissions. The entire exhaust of a sub-group of power cylinders (dedicated cylinders) is routed directly into the intake. These cylinders are run fuel-rich, producing H2 and CO (reformate), with the potential to improve combustion stability, knock tolerance and burn duration. A 2.0 L turbocharged D-EGR engine was packaged into a 2012 Buick Regal and evaluated on drive cycle performance. City and highway fuel consumption were reduced by 13% and 9%, respectively. NOx + NMOG were 31 mg/mile, well below the Tier 2 Bin 5 limit and just outside the Tier 3 Bin 30 limit (30 mg/mile).

Predictions of the volume flow rate through an inlet port were produced by four different commercially available CFD programs suitable for use in a steady flow simulation. These predictions were compared with experimental measurements of an inlet port's discharge coefficients. The experiment performed was a typical steady state flow bench test for an inlet port. Volume flow rates were measured at five different valve lifts. The largest valve lift tested (12.24mm) was the maximum value of lift under actual operation. The smallest valve lift was typical of early valve opening. The tests were performed at two different pressure differences across the inlet port and valve at each of the five different valve lifts. All predictions were made using an RNG k-ε turbulence model. Standard wall functions were used to predict wall friction effects and the energy equation was included to account for compressibility effects.