Fuel injection system
Fuel injection system is the very important part of the Compression Ignition (CI) engine.
The performance of an engine viz. power output, economy etc. is largely dependent on the fuel injection system.
The injection system has to perform important duty initiating and controlling the combustion process.
What is the difference between carburetion and fuel injection?
Duty of both the fuel injection system and the carburetion system is same i.e. to prepare a combustible mixture.
In carburetion system fuel is atomized for proper combustion with the help of high velocity air.
But in the case of injection system, fuel is atomized for combustion with the help of velocity of fuel.
Functional requirements of a fuel injection system
For successful running and getting good performance from an internal combustion engine, the following requirements must be met by a fuel injection system.
- Accurate metering of the fuel injected per cycle.
- Correct fuel injection timing.
- Full control over rate of fuel injection.
- Proper atomisation of the fuel.
- Proper spray pattern to ensure mixing of air and fuel.
- Uniform distribution of fuel in the combustion chamber.
- To supply equal quantity of the fuel in all the cylinders (in case of multi cylinder engine).
- No lag between beginning and end of injection process.
Components of fuel injection system
A fuel injection can comprise of many parts. Some important parts are discussed here.
This is the main fuel tank where fuel is stored
Fuel feed pump
To supply fuel from main fuel storage tank to the injection system.
To meter and pressurize fuel for injection.
To supply fuel in accordance to the load.
To take fuel from the injection pump and supply it to the cylinders.
To filter fuel so that duct and abrasive particles can not enter the injection system . These particles can damage the injection system.