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Difference between petrol and diesel engine

 

 

It’s common in our street roads today seeing vehicles carrying either petrol engine or diesel engine. these two types of automobile engines are the conventional types even though one exists before the other.

Even with the vast usage of the two most drivers confuse the difference and similarities between petrol and diesel engine. well, the primary difference between the two is that a petrol engine works on the otto cycle whereas diesel works on the diesel cycle.

After covering individual articles on petrol (gasoline) and diesel engines, today you’ll get to the difference between the two, their effectiveness and which of them is the best. We’ll also enlighten on the advantages and disadvantages of the engine types.

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Difference between a petrol and diesel engine

Difference between petrol and diesel engine

Petrol (gasoline) engine

Pros and cons of a petrol engine

The petrol engine is an internal combustion engine that uses spark ignition to burn fuel. It runs on relatively volatile fuel known as petrol. In a petrol engine, the fuel and air mixture are done the carburetor before entering the combustion chamber as a gas. Thus, they are generally mixed post-compression.

Just as earlier mentioned, petrol engines work on the otto cycle which consists of two isochoric processes and two isentropic processes. Finally, the existence of a spark plug on the petrol engine is very essential as it’s the device that produces spark so that the gas in the cylinder can explode. This spark plug is powered by the engine ignition system.

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Advantages and disadvantages of a petrol engine

Advantages: 

1. Petrol engines are generally more powerful, by way of horsepower than diesel.
2. Petrol engines also typically benefit from being easier to tune and tune-up.

3. A gasoline engine, which is also known as a petrol engine has a better ratio of cost to power and burns fuel more eco-friendly than diesel performs.

4. Petrol is usually cheaper than diesel fuel.

disadvantages:

1. The disadvantage of the petrol engine is that, generally, its lifespan is almost always shorter than that of the diesel.

2. This practically relates to the fact that diesel engines will usually have a higher residual (resale) value.

3. Gasoline engines get less miles-per-gallon (sometimes significantly) than their diesel counterparts.

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Working principles of a petrol engine:

Diesel engine

Pros and cons of diesel engine

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Also, a diesel engine is an internal combustion engine known as the compression-ignition engine. it was patented by Rudolf Diesel. The working of this engine is quite different from the gasoline engine as the fuel is injected into the combustion chamber and then ignited by the higher temperature of the air in the chamber. This causes the elimination of the spark plug in the engine design.

The higher temperature of the air in the cylinder is due to adiabatic compression. The fuel is not compressed in this engine but only the air. When the diesel fuel is injected into the combustion chamber, it undergoes spontaneous ignition.

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Advantages and disadvantages of diesel engine

Advantages: 

1. It has the highest effective efficiency of all combustion engine

2. The diesel engine can combust a huge variety of fuel

3. Low fuel costs. That is, it is economical.

4. It has a high energy density

5. Good lubrication properties

6. Low risk of catching fire, as flammable vapor is not produce

7. Injection of fuel directly into the combustion chamber, have no intake of air restriction apart from the air filters.

8. Diesel engines have very good exhaust-emission behavior.

Disadvantages: 

1. The disadvantage of the petrol engine is that, generally, its lifespan is almost always shorter than that of the diesel.

2. This practically relates to the fact that diesel engines will usually have a higher residual (resale) value.

3. Gasoline engines get less miles-per-gallon (sometimes significantly) than their diesel counterparts.

Working principle of a diesel engine:

Now let see the difference between petrol and diesel engine in tabular form:

Difference Between Petrol and Diesel Engine

Diesel Engine

Petrol Engine

works on Diesel cycle Works on Otto cycle
Fuel is mixed with air inside the cylinder Air and the fuel are mixed in a carburetor
Ignition is achieved with hot compression Fuel is ignited with an electric spark plug
High initial and maintenance costs Comparatively low initial cost and maintenance cost
Relatively low fuel consumption High fuel consumption.
diesel fuels have low volatilities Highly volatile fuels are used (gasoline)
Generally used in heavy vehicles such as trucks and buses Used in light vehicles such as motorcycles and cars.
High power production Relatively low amounts of power are produced in Petrol engines
High compression ratio Relatively low compression ratio

In general, the difference between petrol and diesel engine is not only from the fuel they use. A lot of things also differential the two engine types such as diesel engines uses fuel injectors and it does not work with the spark plug.

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Now we get to understand that diesel engines are used in much heavier machinery such as tractors, trucks, and buses. Whereas, petrol engines are used on lighter vehicles such as motorcycles, scooters, and cars.

So, which of the two is better:

This question is common among auto students and car enthusiast but is totally wrong. If one of the engines is better than the other, the two won’t have been used in our community today.

The fact about the petrol engine and diesel engine is that they are suitable for specific kinds of vehicles, even though diesel engines are now employed on commercial cars nowadays. Choosing the best among the two also depends on how you drive and from where you are driving.

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The benefits of these fuels may vary depending on the country’s usage regulations compliance. Before the widespread of the electric engine, gasoline engines are common on the road in the United States, before diesel engine begins to gain population in news. However, diesel engines from specific companies have been detonated for their lack of obedience to U.S. emissions laws. In Nigeria, diesel has been more effective and has been widely used among citizens. This is because of weather conditions, making one of the great limitations of the diesel engine to be overlooked. So take your time and memorize the difference between petrol and diesel engines.

In conclusion, we’ve put this article together to clarify the difference between petrol and diesel engine. we also added their advantages and disadvantage and also their working principle.

I hope you enjoyed the reading, if so, kindly comment, share and check some other informative article below. Thanks!

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