الفهرس 
(IGNITION SYSTEMS AND LITREATURE REVIEW)Only 14 pages are availabe for public view
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Abstract
Lean mixture combustion is considered as one solution for the
reduction of exhaust emissions because of the low concentration uf
nitrogen oxides as well as carbon monoxide in the exhaust gas. Also it
reduce the fuel consumption.
The purpose of this work is to construct an ignition system suitable
to be used with lean mixtures which leads to less pollutants in the engine
exhaust as well as better engine efficiency and power.
a) The first stage was directed to design and construct a modified
electronic ignition system with improved specifications, such as; two
energy levels for the spark (high, III mJ flow, 84.5 mJ), wider spark
gap, sensitive for the mixture strength (lean f rich), automatic spark
advance and spark energy change.
b) In the second stage a series of tests was conducted 011 a Peugeot S I E of
four cyolinders having 1976 cm3 swept volume and maximum power
of 58 kW (1968), once with the conventional Spark Ignition System
and then with the modified electronic system.
The effects of spark plug and ignition system variables upon the
engine performance were investigated.
In this study, the effecs of spark plug gap width, spark energy, and
spark duration were investigated for various engine air-fuel ratios,
especially, in the lean mixture region.
III addition to studying each variable independently, the interactions
between the variables were also investigated experimentally.
The engine performance parameters measured were: exhaust
emissions, specific fuel consumption, engine speed roughness of operation
and engine power. Results showed that the engine produced a better performance with
the modified high spark energy ignition system, especially if the spark plug gap was increased to about 1.25 mm. In this case, the engine
produced lower exhaust emissions, lower specific fuel consumption,
smoother engine operation, and higher engine power.