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Laboratory work № 3

FUEL SUPPLY SYSTEM FOR PETROL AND DIESEL
ENGINES

1 The purpose of the work is to study the purpose, general
circuits, principle of operation and design features of fuel supply
systems, and possible problems.

2 Basic theoretical provisions

Learning of appointment of all gasoline engine and diesel
engine systems, it is necessary to establish the location of each of
these instruments on the vehicle. Pay attention to the fact that in
diesels used double fuel purification system (rough and thin).
To understand the structure of the injector (carburetor) and
understand its operation at different modes, you need to know the
possible combustible composition and its impact on the engine. It
is necessary to know the characteristics of the simplest and most
ideal carburetor, the principles of the operation of additional
devices and systems of carburettor, which provide the required
composition of the combustible mixture.
The composition of the combustible mixture is taken to
characterize the excess coefficient of air, which is indicated by the
letter α. This coefficient is the ratio of the amount of air L involved
in the current combustion of fuel to the theoretically required
amount of air L, which would ensure the complete combustion of
this amount of fuel.
If in the combustion of 1 kg of gas takes 15 kg of air, that is,
as much as theoretically necessary, then α = 1,0 and such a mixture
is called normal. For α <1, the mixture is called rich, with α> 1 -
poor. Depending on the mode of operation of the engine, the
carburetor must change the composition of the combustible
mixture. When starting the engine, a rich mixture of α> 0,4 is

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