A New Look at Two-Stroke Engines for Passenger Cars in Light of PNGV Goals for the Coming Decade

The paper explores an alternative for hybrid powertrains: the use of two independently operating two-stroke engine modules in a common housing as the primary and secondary energy converters. A low-energy-capacity regenerative braking system rounds out the total hybrid powertrain.

The reasons to favor two-stroke engines in the modular engine hybrid approach are that the one-per-revolution firing frequency allows smooth engine operation when operating with low numbers of cylinders; and there is a cost and packaging advantage with piston ported engines when compared with the added valve gear complications associated with multiple four-stroke engines.