What is the Main Difference Between Diesel and Petrol Engines?

Car engines mainly separating into two main categories such as; Diesel Engine and Petrol Engine. We already know that. But have you ever thought about the difference between them? This is the exact theme of this article. We will talk about the differences between the diesel engine and petrol engine.


How a Car Engine Works?

As a general concept every car carries the similar engine. Theoretically, all engines have got an internal combustion structure which is designed for converting the fuel’s chemically rich energy source to the mechanical energy. This energy moves pistons up and down in cylinders. This linear motion movement creates the rotary motion which is necessary to move wheels forward. Also, diesel engines and petrol engines convert fuel into energy similarly by using little explosions in engine’s mechanical structure.


What is the Main Difference Between Diesel Engine and Petrol Engine?

The actual main difference between diesel and petrol engine occurs in the phase when serial explosions happen. Inside of a petrol engine, fuel always mixed with air first, then pistons compress this mixture and spark plugs ignite it with sparks. That’s how chemical energy turn into mechanical energy in petrol engine. However, diesel engine has no spark plug. So, fuel compressed into cylinders first, then the fuel sprayed. Because when air compressed it gets warmer and warmer, but the fuel ignites in first contact.  Also, diesel engine’s compression ratio is higher than a petrol engine (in diesel: 14:1 to 25:1) (in petrol: 8:1 to 12:1). Petrol engines usually use low compression ratios to prevent fuel auto ignition. High compression ratios can provide high thermal efficiency and much better fuel economy.


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