Why are diesel engines heavier than petrol?
Why are diesel engines heavier than petrol?
The compression ratio of diesel engines is much higher than petrol engines since the flash point (temperature at which it catches fire) of diesel is higher than petrol. Thus a heavier/denser metal is required for the engine assembly.
Why diesel engines are larger?
The first reason is a much higher compression ratio. This is the ratio of the maximum and minimum volume in the cylinder of an engine. It’s made larger in a diesel engine due to a longer stroke, meaning the piston is moving up and down a larger internal volume of cylinder.
Which is more heavier petrol or diesel?
The calorific value of diesel fuel is roughly 45.5 MJ/kg (megajoules per kilogram), slightly lower than petrol which is 45.8 MJ/kg. However, diesel fuel is denser than petrol and contains about 15% more energy by volume (roughly 36.9 MJ/litre compared to 33.7 MJ/litre).
Which engine is heavy and why?
The gas engine will be built lighter because the extra strength is not needed, the extra weight not desired, and it is cheaper to build it lighter. Consequently, the diesel engine is heavier than a similarly sized gasoline engine.
What makes a diesel engine more efficient than a petrol engine?
Diesel engine uses simple mechanism for combustion unlike in gasoline engine. Removal of ignition system not only makes the mechanism simpler but also reduces the risk of improper combustion due to damage in ignition system. In short burning of the fuel is easy and always accessible. This results in higher efficiency diesel engine.
Why does a diesel engine have higher torque?
Torque is the name of the game. High torque is needed to move heavy loads. If comparing a gasoline engine to a comparable diesel engine the diesel will always have higher torque. The higher torque comes from the need for a higher compressing ratio needed for compression ignition. To achieve the higher compression ratio a longer stroke is required.
Which is cheaper to run, diesel or petrol?
At the time of writing, diesel fuel is around 40% cheaper per liter than petrol. This means diesel vehicles will be cheaper to run, which also explains why buses and most taxis have diesel engines. Because diesel engines are so efficient, cars can get incredible mileage out of them.
Why is the compression ratio higher in a diesel engine?
The compression ratio is much higher in diesel as compared to gasoline because in diesel engine air is alone compressed inside the cylinder and it’s a known fact that gas easily compresses then liquid. This is not so in gasoline engine because air-fuel mixture is compressed inside the cylinder.
Which is better a diesel or a petrol engine?
Petrol engines have a lower compression ratio compared to diesel engines thanks to the aid of the spark plug and higher volatile fuel. On the opposite, diesel engines’ higher compression ratio results in higher torque.
Why does a diesel engine have more torque?
As a consequence of a higher compression ratio (longer stroke), diesel engines produce more torque which means you get more acceleration off the line. This is also the main reason for diesel cars having a much smaller power band, so you generally get more torque but spread over a smaller area.
Why is the thermal efficiency of diesel engines higher than that of?
This results in higher efficiency diesel engine. Diesel fuel is a heavier hydrocarbon in which carbon and hydrogen are strongly bonded with each other. And when energy is supplied in form of heat it gets explode releasing much higher energy then gasoline. In short diesel fuel has higher energy density then gasoline which results in huge explosion.
The compression ratio is much higher in diesel as compared to gasoline because in diesel engine air is alone compressed inside the cylinder and it’s a known fact that gas easily compresses then liquid. This is not so in gasoline engine because air-fuel mixture is compressed inside the cylinder.
