Why is compression ratio highest id diesel engine?

Answer 1

Diesel engines come in all sizes. Some smaller and some quite larger than gasoline engines. A diesel engine makes no more H.P. than a gasoline engine but makes lots more torque and it's H.P. at low RPMs. Diesels typically have a compression ratio of around from 16 to 1 to as high as 23 to 1. Most gasoline engine will have around a 9 to 1 ratio. The higher compression ratio of a diesel allows it to make much more torque at lower RPMs. Torque is pulling power which is what a truck needs.

Answer 2

A diesel engine is a compression-ignition engine, whereas the petrol engine uses spark ignition.

The injected diesel fuel spray will ignite in the highly compressed air inside the combustion chamber. This is due to the very high temperatures obtained as a result of the high compression ratios. The timing of the injection is important to maximise the combustion process.

In petrol engines the compression ratios are kept much lower to curb the possibility of detonation, and the fuel-air mixture is optimised for a particular compression ratio which will be ignited by a spark at the correct timing.

Answer 3

if you're talking about the exhaust, it's because diesel engines are normally bigger which means they need bigger exhaust pipes to let all the carbon dioxide/monoxide out, which let's more sound exit. big 18 wheeler's engines range from 10 to 12 liter straight 12 diesel engines. where a normal sized car either has around a 2.4 liter 4 cylinder, or around 3.5 liter V6 engines. both very small compared the hauler trucks.

Diesels are noisier due to how they ignite the fuel. It is ignited by compression. Diesel engines have a compression that is 2 or 3 times that of a gas engine. The compression requires stronger parts and does create some noise.

Answer 4

Diesel engines have much higher compression than gasoline engines, requiring a thicker cylinder block.

Answer 5

Diesel engines dont have a spark plug, the pressure is what ignites the fuel, therefore they need the right pressure to ignite it, which, thanks god, is pretty high