Why don t diesel cars have spark plugs?

First, because the diesel engine directly compresses the mixed gas of air and oil to the ignition point, it automatically ignites, which is called compression ignition. No external sparks are used to ignite, so no spark plugs are used.

And the gasoline engine. The compression ratio is not as high as that of a diesel engine, and ignition is required to ignite the gas in the cylinder.

Second, the combustion speed of diesel is slow and stable, so the high compression ratio is adopted, the air temperature will rise during the compression process, and the diesel fuel will be burned when it is injected, which is called compression ignition. Gasoline burns fast and stable, so compression ignition cannot be used, and the ignition type of spark plug is used to break through the air at the appropriate time to ignite the oil-gas mixture. Diesel engine.

Also known as "compression-ignition internal combustion engine", an internal combustion engine with diesel fuel. If the temperature rises to the ignition point of diesel, the diesel fuel is sprayed into a mist into the cylinder with an injector, and the diesel meets the hot air, that is, it ignites and burns by itself. The high-temperature and high-pressure gas produced by combustion expands in the cylinder and pushes the piston to do work.

As a result, diesel engines do not have ignition coils, spark plugs, and ignition systems such as distributors.

Diesel cars are ignition rings without spark plugs. Gasoline cars will have spark plugs regardless of whether they are EFI or not. The diesel engine sucks air into the cylinder, at the end of the compression stroke, the temperature in the cylinder reaches 500-800, then the fuel injector sprays the diesel fuel into the combustion chamber in the form of a mist at high pressure, and the hot air is mixed with the violent evaporation to form a combustible mixture.

Diesel cars have no spark plugs.

The advantages of diesel engines are high torque and good economic performance. The working process of a diesel engine has many similarities with a gasoline engine, and each working cycle also goes through four strokes: air intake, compression, work, and exhaust.

However, because the fuel used in diesel engine is diesel, its viscosity is greater than that of gasoline, it is not easy to evaporate, and its spontaneous ignition temperature is lower than that of gasoline, so the formation and ignition of combustible mixture are different from those of gasoline engine. The main difference is that the mixture in the cylinders of a diesel engine is compression-ignited, not ignited. When the diesel engine is working, it is air that enters the cylinder, and when the air in the cylinder is compressed to the end, the temperature can reach 500-700, and the pressure can reach 40-50 atmospheres.

When the piston is close to the top dead center, the fuel injector of the oil supply system injects fuel to the cylinder combustion chamber in a very short time with extremely high pressure, the diesel oil forms fine oil particles, mixed with the air of high pressure and high temperature, the combustible mixture burns by itself, and the violent expansion produces explosive force, pushing the piston down to do work, at this time the temperature can reach 1900-2000, the pressure can reach 60-100 atmospheres, and the torque generated is very large, so the diesel engine is widely used in large diesel equipment.

Diesel locomotives are all ignited. Generally, internal combustion engines have four strokes. In the first stroke, a mixture of air and fuel is sucked in. Second stroke: Compressed gas. Third stroke: Combustion to do work. Fourth Stroke: Exhaust.

The difference between a gasoline engine and a diesel engine: After the diesel engine compresses the mixture to a certain extent at the end of the second stroke, the diesel temperature rises to the diesel ignition point, which can burn by itself and does not need to be ignited. At the end of the second stroke, the gasoline engine has an increased temperature, but it does not reach the ignition point, and a spark plug is required to ignite to burn.

Hello, because diesel engines are compressed and self-ignition, there are no spark plugs.

The temperature in the tank directly ignites the combustible gas, I hope it can help you.

Diesel carsSpark plugsIt's still called a spark plug.

The spark plug (Sparkplug), commonly known as the fire nozzle, is used to send pulse high-voltage electricity from the high-voltage wire (fire nozzle wire).

The discharge breaks down the air between the two electrodes of the spark plug and generates an electric spark to induce the gas mixture in the cylinder. The product is divided into standard spark plugs and insulators.

Protruding spark plugs, etc.

Product Role. Where is a gasoline engine.

There are spark plugs, one for each cylinder, and some high-speed gasoline engines are also equipped with two spark plugs per cylinder. The spark plug is a small part, but it is extremely important, without which the engine would not be able to move. Anyone who drives a lot will be familiar with this thing.

The function of the spark plug is to put the ignition coil.

The resulting high-voltage electricity (above 10,000 volts) is introduced into the engine cylinders, creating sparks between the gaps between the spark plug electrodes to ignite the mixture. The working environment of the spark plug is extremely harsh, with an ordinary four-stroke gasoline engine.

For example, the spark plug has a temperature of only 60 and a pressure of 90 kpa during the intake stroke.

When ignition burns, the temperature will rise to 3000 degrees instantly, and the pressure will reach 4000kpa; The alternating frequency of this kind of quenching and heating is very high, which is not something that ordinary materials can cope with, and it is necessary to ensure the insulation performance, so the material requirements for the spark plug are very demanding.

The spark plug is small, but it is not simple to construct. It has two components: an insulator and a metal shell: the metal shell is threaded and is used to screw into the cylinder; An insulator is installed in the shell, and a central electrode is connected to the high-voltage wire from the distribution panel through the central electrode or a wiring nut at the upper end of the central electrode.

There is a grounding electrode welded on the lower end face of the shell, and there is a millimeter gap between the central electrode and the section of the grounding electrode, and the high-voltage electricity will burst out to ignite the mixture when it enters the ground through this gap.

The spark plug, commonly known as the fire nozzle, is used to discharge the pulse high-voltage electric discharge from the high-voltage wire, penetrate the air between the two electrodes of the spark plug, and produce an electric spark to induce the mixed gas in the gas cylinder. The main types are: quasi-type spark plugs, edge body protruding spark plugs, electrode type spark plugs, seat type spark plugs, polar type spark plugs, surface jump fire type spark plugs, etc.

The function of the spark plug is to introduce tens of thousands of volts of high-voltage electricity into the combustion chamber, and generate an electric spark to ignite the mixture, and cooperate with the ignition system and oil supply system to make the Mingque engine work, to a large extent, the performance of the common motive.

The main species. According to the calorific value, there are cold type and hot type; According to the electrode material, there are nickel alloys, silver alloys and platinum alloys; If you are more professional, the types of spark plugs are generally as follows:

1. Quasi-type fire annihilation silver flower plug: the skirt of the insulator is slightly retracted into the end face of the shell, and the side electrode is outside the end face of the shell, which is the most widely used.

2. Spark plug with protruding edge: the skirt of the insulator is long, protruding beyond the end face of the shell. It has the advantages of large heat absorption, good anti-fouling ability, etc., and can be directly cooled by the intake air to reduce the temperature, so it is not easy to cause hot spot fire, so the thermal adaptation range is wide.

3. Electrode spark plug: its electrode is very thin, characterized by strong sparks, good ignition ability, and can ensure that the engine is fast and reliable in the cold season.

Starting, wide thermal range, can meet a variety of purposes.

4. Seat-type spark plug: its shell and screw-in thread are made into a cone, so it can maintain a good seal without a washer, thereby reducing the volume of the spark plug and making it more beneficial to the design of the engine.

5. Polar spark plug: the side electrode is generally two or more than two, the advantage is that the ignition is reliable, and the gap does not need to be adjusted frequently, so it is often used in some gasoline engines where the electrode is easy to ablate and the spark plug gap can not be adjusted frequently.

6. Surface skip type spark plug: that is, along the surface gap type, it is the coldest type of spark plug, and the gap between the central electrode and the end face of the shell is concentric.

There are no spark plugs because diesel cars are compression-ignited. But the diesel engine has a glow plug that helps the diesel engine to catch fire. Since the temperature in the combustion chamber is much higher than the spontaneous ignition point of diesel (350-380), diesel burns on its own or burns by fire.

This is the working principle that the old diesel engine can be burned without an ignition system.

Do diesel engines have spark plugs.

The spark plug is an important element of the ignition system of a gasoline engine, which can introduce high-voltage electricity into the combustion chamber and cause it to skip the electrode gap and generate a spark, thereby igniting the combustible mixture in the gas cylinder.

It is mainly composed of a wiring nut, an insulator, a wiring screw, a central electrode, a side electrode and a shell, and the side electrode is welded to the shell. The spark plug is installed on the side or top of the engine, and the early spark plug is connected to the distributor by the cylinder line, and in the last ten years, the engine on the car has basically been changed to the ignition coil directly connected to the spark plug.

The operating voltage of the spark plug is at least 10000V, and the high voltage is generated by the ignition coil from 12V electricity, which is then transmitted to the spark plug. Under the action of high voltage, the air between the center and side electrodes of the spark plug will rapidly ionize, forming positively charged ions and negatively charged free electrons. When the voltage between the electrodes reaches a certain value, the number of ions and electrons in the gas increases like an avalanche, and the air loses its insulation, and the gap forms a discharge channel, and the breakdown phenomenon occurs.

Hello. There is no spark plug on the diesel engine. Diesel Haruko engine at work time.

The fuel injector injects diesel fuel into the cylinder. Ignited by trembling pressure. So.

There are no spark plugs on the diesel engine. The gasoline engine is ignited by spark plugs.