advances in internal combustion engines and fuel technologies pdf

In the context of a Spark Ignition engine, the inherent complexity of premixed combustion is
exacerbated by a range of engine variables that render the process highly transient in nature
and not fully predictable. The present work aims to contribute to the continuous research effort
to better understand the details of combustion and be able to model the process in gasoline SI
engines.

Coexisting fossil fuels depletion and environmental concerns, along with an alarming
connection between traditional internal combustion engines emissions and human health
degradation [1], have in recent years driven a strong research interest upon premixed SI
combustion of energy sources alternative to gasoline, including liquid alcohols like ethanol,
and gaseous fuels like hydrogen.

However, the advancements enjoyed by gasoline-related
technology and infrastructure in the last 40 years have eroded the potential advantages in
efficiency and emissions offered by alternative fuels [2], and the SI engine running on gasoline
continues to be the most common type of power unit used in passenger cars (Port-Fuel Injection
gasoline engines accounted for the vast majority (91%) of all light-duty vehicle engines
produced for the USA market in 2010 [3]).

The characteristics which make the gasoline engine well suited to light-weight applications
includerelativelyhighpowertoweightratio,acceptableperformanceoverawiderangeofengine
speeds, the vast infrastructure for gasoline and lower manufacturing costs when compared to
diesel or more modern hybrid technologies [4]. The continuing exploitation of spark ignition
engines reflects a history of successful development and innovation.

These have included the electronic fuel injection system, exhaust emissions after-treatment, Exhaust Gas Recirculation and, increasingly, the use of some form of variable actuation valve train system. The modern SI engine, addressed to as high-degree-of-freedom engine by Prucka et al. [5], may also feature flexible fuel technology, typically to allow running on ethanol-gasoline blended fuels.