Difference Between Diesel Engine and Petrol Engine

Diesel Engine vs Petrol Engine
 

Diesel and petrol are the main engines we have in the automotive industry today, and both are internal combustion engines. There are so many debates and swordplays about diesel and petrol engines, as both have advantages as well as disadvantages. Diesel engine uses a compression ignition technology to burn the fuel. That is, in a diesel engine, fuel is injected into the compression chamber at a very high pressure and it is compressed in the compression chamber. Then ignition will take place. However, unlike in diesel engine, petrol engine has a different technology called spark ignition technology. It has a spark plug, and after each compression stroke, spark ignition will occur. Diesel engines use 30% less fuel than petrol engines so that it reduces the unhealthy emissions. However, diesel is more dangerous from the point of view of solid particles emitted from the diesel engines suspended in the air. It causes some respiratory problems since it has a tendency to deposit in our lungs. The smoothness of the petrol engines is a strong advantage, which is liked by people. Likewise, there are both pros and cons when comparing a diesel engine and a petrol engine.

Diesel Engine

Diesel engine is an internal combustion engine that uses diesel as fuel. Diesel engines are very efficient. The combustion process of the diesel engine follows a different technology. It takes air, which is compressed up to 200 bars and fuel is injected in to the air at the expansion stroke. With the high pressure and temperature, an auto ignition takes place. Therefore, the diesel engine does not need a spark plug. Hence, no spark plug related engine problems. Since it has no specific ignition system, the complexity has been reduced.

Diesel engines have a very high thermal efficiency and higher compression ratio. It is difficult to start a diesel engine, as greater cranking efforts are required to overcome this higher compression ratio. Since it has a higher torque, some heavy loads can be pulled easily. Another advantage is that diesel engines can be turbocharged easily, as there is no fuel in the cylinder of diesel engine. Because of this, turbocharger can suck as much air as it can without creating any problem. However, diesel engines are noisier and need frequent maintenance, but diesel is cheaper than other fuel.

Petrol Engine

Petrol engine is also an internal combustion engine that uses petrol as a fuel. This has a different method of mixing fuel and air. It uses a spark plug to initiate a combustion process. In petrol engine, fuel and air are pre mixed before the compression process. Since it uses a spark plug, the internal combustion process is smooth. Therefore, driving a petrol vehicle gives us a pleasant experience. Main advantage of using petrol is, cheaper than any other fuel. In addition, petrol engines are lighter than diesel engines. However, the mileage is comparatively less in petrol engines. Moreover, petrol engines have more chances of fire hazards. When the load is reduced, petrol engine is much better since it has good fuel and air mixing.