why can diesel not be spark ignited and petrol not be compression ignited?

Question

why cant we use diesel in petrol engines and vice versa? economy is one point, but is it feasible 2 use them interchangeably wid some variations, like compression ratio or something?

Answer 1

Diesel CAN be spark lighted, but the spark-plug is not neccesary, because of high compression in the cyinder of Diesel engine (ratio between top point and bottom point of the piston is 18-25), which produce temperatures up to 600oC, due to the equation of ideal gas.

For a petrol engine spark-plug is neccesary, because it revolves at high rpm, so high compression cannot be provided. Theoretically, both types of fuel can be used at both types of engines, but with significant losses in energy and speed, and Diesel engine could be damaged severely, if the petrol is not injected, but sucked-in through carburetor system.

The only reason for development of two different types of engines is the speed of combustion of those two fuels. Petrol combusts much faster than the Diesel, so it could be ignited too early if loaded in Diesel engine. On the other hand, spark should ignite the Diesel fuel much earlier than the petrol, in a petrol engine, for providing enough time for complete combustion and usage of all produced heat during diesel combustion.

Supplying system is another obstacle. Diesel can clog the carburetor, and petrol can evaporate in supplying pipeline and form vapor clog, thus obstructing loading into the cylinder.

This problem is much wider than this, but there is not enough space to discuss it, so if You need additional informations, e-mail me and I will be happy to provide all informations that You may need.

Answer 2

It's all about compression. Gasoline engines are compressed about 8:1 to 12:1 ratio. Diesel engines are compressed to around 16:1. Gasoline, if used in diesel engines, ignites prematurely and pushes the piston down during the compression stroke, resulting in bent connecting rods (ruining the engine).
Diesel fuel is less volitile and burns much slower at a lower compression, thereby not being efficient in a gasoline engine.

Answer 3

Petrol is a really flamable gas, it may ignite on the faintest spark or flame, it does not require intense tiers of warm temperature. In petrol engines the chamber is a mixture of gas and air to get the wanted result. Petrol engines are often used for speed. Diesel, once you're trying gentle a hearth with it it often does not make a huge difference on your efforts compared to what petrol can do. It calls for warmth and it really is the reason diesel engines have glow plugs to warmth the air from the inlet to make the diesel contained in the chamber ignite. Diesel engines use injectors to spray the diesel to ignite. Diesel engines are often used for ability to pull and push issues. it really is in straightforward words that those fuels are made and processed in a distinct way which makes them artwork in a distinct way too. Diesel replaced into invented first.

Answer 4

Actually, they can, to a degree. Any fuel can be used in a Diesel engine; I believe that Rudolf Diesel used powdered coal. But Diesel fuel (i.e., oil) works best because it burns evenly at the temperature achieved by compressing air in the cylinder.
Diesel fuel does not work well in a spark engine because it is not as flammable as gasoline, and once ignited, tends to knock. Natural gas (methane) and alcohol (methyl or ethyl) can be made to work if you use an appropriate carburetor; natural gas vehicles are popular for delivery routes.

Answer 5

I think it's got something to do with the flash point of each. Petrol, or gasoline, I'm assuming you mean, has a high flash point, whereas diesel is much lower. What's INTERESSTING about the two, is DIESEL will burn almost COMPLETLY, with almost NO greenhouse gas emissions. Whereas GASOLINE is almost the EXACT OPPOSITE! Only 30%-40% of gasoline burns in a car, and the rest goes out the tailpipe in CO and CO2 emissions!!!

Answer 6

They can be interchanged, The the U.S. mil. has had multi fuel engines since the Koren war. The fuel injection is the key, the fuel being injected at the right moment, ford built a limited number of them for there cars a few years ago, didn't sell too well. Although they do work very well.

Answer 7

Interesting thread!

Answer 8

since compression ratio is quite different so two mwthod r used .....and i cant tell u more ........... go on reading ur mechanical book

sam ;)

Answer 9

Was on Y Answers for something or other, then this topic was displayed on the sidebar...

Answer 10

Was gonna ask this too