Apart from fascinating you with their great variety of design and technology, cars also fulfil the basic function of carrying you from one point to another. And at the core of this basic function is the engine.
The mobility of a car is made possible through the engine, which works by converting energy generated from burning fuel into mechanical energy. This mechanical energy moves the wheels and powers the gears. So, here’s all you need to know about your car engine!
A typical engine consists of cylinders, the number varying from four to six to eight. Depending on the layout and number of cylinders an engine has, it is called a “V4” or a “V6” or a “V8” engine. The cylinder, pistons, and the cylinder head together form the combustion chamber of the engine. Inside the cylinders, close fitting pistons move up and down. This up and down movement causes the crankshaft to rotate which is connected to the piston via a connecting rod also called a con rod. A spark plug is present at the top of cylinder which ignites the mixture of fuel and air. The camshaft is responsible for making the valves open and shut alternatively.
A four-stroke engine is what adorns majority of the cars to make them run. Heat energy produced by the mixture of gasoline and air creates controlled explosions inside the piston present in the engine, which is then converted into mechanical energy to propel the car. Since the whole process takes place inside the engine, it is called an internal combustion engine. The four strokes which happen repeatedly in this process comprise of the intake stroke, the compression stroke, the power stroke, and exhaust stroke.
Intake Stroke: The inlet valve opens up during this stroke and air gets into the cylinder as the piston begins its downward journey. As soon as the air is in, a little fuel is injected into the cylinder from the electronic fuel injector. The intake valve closes when the piston reaches the bottom of the cylinder.
Compression Stroke: In this stroke all the valves are shut and piston moves back up to push and compress the combination of air and fuel. The purpose of compression in the tiny space is to create a more powerful explosion.
Combustion Stroke or Power Stroke: Now that the piston has reached the top, the spark plug creates a spark resulting in the ignition of the compressed fuel-air mixture. This causes the explosion releasing a tremendous amount of energy which pushes the piston down again to the bottom of the cylinder.
Exhaust Stroke: The exhaust valve opens and piston slides back up due to the continuous motion of the crankshaft. This forces the waste gaseous mixture out of the exhaust valve making room in the cylinder for fresh air to repeat the whole cycle again.
The exhaust gases go to the catalytic converter where toxic compounds like Carbon monoxide, Nitrogen oxides, and hydrocarbons are rejected. The muffler, also known as silencer, cools down the exhaust gases and reduces their noise considerably before emitting them. Finally the emissions are out of the car through a tail pipe.