The engine's behavior is determined by the combustion ratio. It evaluates the motor cylinder's capacity to squeeze and air and fuel. Various engine types such as diesel and petroleum gasoline acquire varying degrees of compression ratio between them.
However, more often than not, a diesel engine has a higher compression ratio than a petroleum gasoline one. Why is that? Let's find out the basic reasons why diesel engines offer higher compression ratios than their other counterparts.
Reasons for the Higher Compression Ratio
- Depends on the Application: Diesel engines are the engines of choice for gigantic automobiles or heavy vehicles like truck, ships, and locomotives. They're powerful enough to pull the weight of these monstrosities without breaking down themselves. They're able to do this by having higher torque application. In order to turn such a vehicle on, the motor requires huge amounts of energy that then leads to the augment combustion rate or higher compression ratio. Diesel engines need a higher compression ratio because it deals with big rigs and whatnot.
- The Air Compression Process: The air compression process in a diesel engine, where air is compressed with a large cylinder inside it, happens so fast with such a high compression ration that fuel is combusted much quicker than in petroleum engines. To be more specific, the quickness and abruptness of the diesel engine air compression process is what ultimately gives it a higher compression ratio. This is also thanks to the size of the engine cylinder, of course. In this case, size does matter.
- Knocking Evasion: Petroleum engines tend to face the serious issue of knocking. It comes about when the cylinder of the engine undergoes abnormal combustion. Luckily, a diesel engine actually prevents or evades the knocking problem and knocking is something you'll only usually see in gasoline engines. Bigger cylinder sizes enable diesel engines to have enough space for the fuel to run and get combusted immediately within it, thus reducing knocking occurrence from the start.
- The Spark Plug: A diesel engine only requires air compression in order to ignite its diesel fuel into usability because its fuel is much more volatile. Petroleum or gas engines, in contrast, require spark plugs to create the spark that combusts their less volatile fuel type. The diesel engine has a high compression ratio that's present in order to ignite the fuel, thus removing the need for spark plugs with diesel-type vehicles like tractors and trucks as well as vans and SUVs. In essence, a diesel engine has an elevated compression ratio in order to remove the need for a spark plug to ignite the fuel because its air compression is enough to do the job.