Why is the compression ratio of petrol engines lower compared to diesel engines?

Question

Accepted Answer

Petrol engines have lower compression ratios compared to diesel engines.

Petrol engines have lower compression ratios to prevent knocking or detonation.
Diesel engines have higher compression ratios to ignite the fuel without spark plugs.
Higher compression ratios in diesel engines result in better fuel efficiency and torque.
Petrol engines require lower compression ratios to accommodate the lower octane rating of petrol fuel.
Lower compression ratios in petrol engines allow for smoother operation and quieter combustion.

Accepted Answer

The compression ratio in diesel engines is typically higher than in petrol engines because diesel engines rely on compression ignition, where the fuel ignites due to the heat generated by compressing air in the cylinder. Higher compression ratios in diesel engines lead to better efficiency and power output. Petrol engines, on the other hand, use spark ignition, so they don't require as high compression ratios.

Accepted Answer

lack of a spark plug

Accepted Answer

Diesel, on the other hand, requires the cylinder to compress the air to the point where injecting diesel fuel instantly combusts the air-fuel mixture. This is why a diesel engine has a higher compression ratio as it compresses a larger volume of air per cylinder to ensure the fuel can be used for combustion

Accepted Answer

Diesel, on the other hand, requires the cylinder to compress the air to the point where injecting diesel fuel instantly combusts the air-fuel mixture. This is why a diesel engine has a higher compression bustionratio as it compresses a larger volume of air per cylinder to ensure the fuel can be used for com

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Why is the compression ratio of petrol engines lower compared to diesel engines?

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