why spark plugs r not used in desiel engines ?

Answer 1

they spray in the fuel when they want it to fire neer top dead center the tempiture ot the compressed air is hot enoulf to ignite it

Answer 2

The heat of compression alone ignites diesel fuel. You must remember diesels are high compression motors 15 -17.1. The fuel is injected directly into a fuel cell inside the combustion chamber fuel cell that swirls and preheats the fuel. In the Lanova fuel or power cell system the fuel cell is bolted on the opposite side of the fuel injection nozzle were the high pressure fuel squirts into the fuel cell that bolts 180 degrees opposite on the cylinder head. As the piston gets close to TDC the heat inside the fuel cell ignites the fuel. Driving the piston back down.
Some folks confuse the glow plugs as a fuel ignitor. This isn't the case at all. Glow plugs pre-heat the air space inside the intake manifold and or combustion chamber so that the first instant the starter rolls the motor over the heat of the glow plugs will pre-heat the air space to get quick ignition. When you release the starter switch the glow plugs turn off.

Answer 3

Diesel fuel is a light distillate fuel oil. Because of this the oil has to be atomized into a fine mist then mixed with an appropriate amount of air. Once this is done the stoke of the piston has to compress the fuel air mixture which generates enough heat for it to ignite. A glow plug is used for cold starts as the engine needs to warm up before they are no longer needed (a glow plug is similar to what you would see in a toaster or some stove tops). Diesel fuel also has a higher amount of energy than gasoline does for the same amount of fuel. This makes diesel more efficient and better for lower torques. A problem with diesel fuel however is that it's boiling point is higher than that of water, and at about 20deg.F it starts to get thicken. this makes it not as suitable for colder climates. Hope this helps!

Answer 4

In a diesel engine, air is sucked into the cylinder and is compressed to an extremely extreme tension(a million:sixteen is the proper tension ratio). for this reason the temperature of air shoots up,reaches an extremely extreme fee. At this ponit, diesel is injected into the cylinder interior the form of a great spray. because of the extreme temperature of the air, diesel directly burns up. subsequently diesel engines do no longer want spark plugs(that are used to produce a spark to burn petrol in petrol engines).

Answer 5

I never realized how many people have NO clue what purpose glow plugs have! Glow plugs do not ignite the diesel fuel.Glow plugs are simply to pre heat the cylinders for cold weather starts. The diesel is ignited in the cylinder by the compression.

Answer 6

Gee....first off, glow plugs are used to aid in starting a cold
diesel engine and not to fire the cyl or cause combustion.
The compression ratio in a diesel engine is so great that it causes the mixture to ignite..... there is lots of technical jargon for this but that is the basic picture

Answer 7

The diesel fuel explodes under the high compression temperatures in the cylinder without needing a spark.

Answer 8

Diesel fuel has a higher density that gasoline and reguires more fire power to ignite. This is done by a glow plug that gets really hot.

Answer 9

Spark plugs wouldn't work, that's why. They still have an eqivilent, they are called glow plugs. Same thing but for diesel.

Answer 10

Deisel ignites easier than gasoline. It ignites just due to the pressure and doesn't need a spark.