Design and Simulation of Two Stroke Engines

Chapter 7 - Reduction of Fuel Consumption and Exhaust Emissions
Fig. 7.30 Relative positioning of fuel injector and spark plug for direct in-cylinder
injection of fuel in a spark-ignition engine.
literature is full of them. The basic approach is the stratified charging of the cylinder by the
"device" of Fig. 7.29 with a premixed charge of vaporized fuel and air followed by mixing
with the trapped cylinder charge and a homogeneous combustion process.
The fundamental advantages and disadvantages of stratified charging and stratified combustion
processes have already been discussed in Sec. 7.1.2.
In the following section, some design approaches to stratified charging will be discussed
in greater detail, presented together with the known experimental facts as they exist at this
point in history. These are very early days in the development of this form of the two-stroke
cycle engine.
7.4.1 Stratified charging with homogeneous combustion
Stratified charging has been tested in various forms and by several research groups and
organizations. The most significant are discussed below in terms of their applicability for
future use in production as power units which will rival the four-stroke engine in hydrocarbon
emissions and fuel consumption levels, but which must retain the conventional advantages
with respect to carbon monoxide and nitrogen oxide emissions.
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