fuel supply system.pptx
TRANSCRIPT
Fuel Injection System
By V.SHYAMU
Fuel Injectors
Introduction
Fuel injection is a system for admitting
fuel into an Internal Combustion Engine
Fuel injection atomizes the fuel by forcibly pumping it through a small nozzle under high pressure
Objectives
Power output
Fuel efficiency
Emissions performance
Accommodate alternative fuels
Reliability
Driveability and smooth operation
Initial cost
Maintenance cost
Diagnostic capability
Range of environmental operation
Engine tuning
Strict emission standards require precise fuel delivery.
Computers used to calculate fuel needs.
EFIS is very precise, reliable & cost effective.
EFI provide correct A/F ratio for all loads, speeds, & temperature ranges.
Injector
Electromechanical device
Controlled by ECM
Engine rpm determines
when injector opens
How long it stays open determined
by:
Engine temp
Engine load
Throttle pos.
O2 sensor voltage
FunctioningM
eter
ing
Injector
uses
solenoid
Mass
airflow
sensor
Throttle position sensor Fuel Pump
Fine tuning
by Oxygen
Sensor
Injectors in operation
Various Injection Schemes
Single Point Injection (SPI)
Continuous InjectionCentral Port Injection (CPI)
Multi Point Injection (MPI)
Direct InjectionSwirl Injection
Diesel Engines
Petrol Engines
Injection
Single Point
Injection
Injects Fuel at throttle
body
Fuel Pressure- 10-15 psi
Continuous Injection
Flows at all times
Fuel Distributor
Central Port Injection
Poppet valves
Batch fire
Multi Point Injection
Injects into intake ports
40-60 psi
Sequential Batched
Injection
Direct
Injection
Higher precision 26000 psi
Swirl Injection
angular
Gas turbine liquid rocket
Injection
Advantages
EFI systems require little regular maintenance whereas carburettors typically requires seasonal and/or altitude adjustments.
Airflow is often improved with fuel injection, the components of which allow more design freedom to improve the air's path into the engine.
By optimizing the homogeneity of cylinder-to-cylinder mixture distribution, all the cylinders approach their maximum power potential and the engine's overall power output improves.
Dis-Advantages
An EFI system requires several peripheral components in addition to the injector(s), in order to duplicate all the functions of a carburettor.
During times of fuel metering repair is that early EFI systems are prone to diagnostic ambiguity.
A single carburettor replacement can accomplish what might require numerous repair attempts to identify which one of the several EFI system components is malfunctioning.
Carburetor
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Fuel system components• FUEL INJECTION PUMP - Fuel injection pump sucks fuel from the tank ,
pressurizes the fuel to approx. 600 - 1000 bar and sends it to the injectors.– Inline FIP - Has separate pumping chambers for each cylinder– Rotary FIP(Distributor pump) - Has one pumping chamber and the pump distributes
to each cylinder as per sequence- firing order
• INJECTORS - Inject the high pressure fuel in to each cylinder.
• FUEL FILTER - Filters the fuel from dirt & sediments, since the Fuel injection pump requires clean fuel.
Fuel system components• FUEL INJECTION PUMP - Fuel injection pump sucks fuel from the tank ,
pressurizes the fuel to approx. 600 - 1000 bar and sends it to the injectors.– Inline FIP - Has separate pumping chambers for each cylinder– Rotary FIP(Distributor pump) - Has one pumping chamber and the pump distributes
to each cylinder as per sequence- firing order
• INJECTORS - Inject the high pressure fuel in to each cylinder.
• FUEL FILTER - Filters the fuel from dirt & sediments, since the Fuel injection pump requires clean fuel.
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Mechanical Fuel Pump
Fuel pump mechanical
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Fuel pump electrical
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Injection system
In the C.I. engine the fuel is injected intothe combustion chamber, it the has to mixthoroughly with the air, ignite and burn all at the same time. To insure this happens, twotypes of combustion chamber have beendeveloped.
DirectInjection
Indirect Injection
Fuel Injector
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Common rail fuel injection system
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Common rail injection system
Air Intake and exhaust system
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Supercharger
• It takes power from engine to compress the air by using belt drive.
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muffler/ silencer
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Mufflers
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