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gasoline engine fuel supply are two main methods of carburetor and fuel injection means.
Carburetor:
Fuel supply mode is conventional gasoline engines have been widely used. Mainly using high-speed airflow gasoline atomized into very small droplets and mixed with air, and the cylinder intake gas mixture and ignited work, but not precisely control the carburetor, the engine load can not be quickly changed in normal driving to reflect, to adjust the concentration of the mixture. Often resulting in incomplete combustion engine of the state, so the content of harmful substances in exhaust emissions can not meet the increasingly stringent emissions regulations, and it will result in higher fuel consumption, it is now gradually being eliminated out.
Fuel Injection:
At present embodiment fuel supply is commonly used cars. It is not the carburetor, but gasoline pressurized by a high pressure gasoline was sprayed directly into the intake pipe to be sucked into the cylinder. Since the nozzle can be more accurately control the fuel injection amount, at any time to adjust the concentration of the mixture, the operator reflecting the sensitivity improves drivability.
The first is a single point injection fuel injection, fuel injected into the intake manifold, but there is unevenness in each cylinder into the oil phenomenon, so gradually directly to the intake manifold of each cylinder of the multi-tube injection substituted injection point. The injection mode is divided into two mechanical and electronic clock. They are mechanically adjustable nozzle and electromagnetic valve opening and closing control. Since the air-fuel ratio control precision mechanical adjustment worse than an electronically controlled, so than most of today’s gasoline engines are electronically controlled multi-point fuel injection.
Now the latest fuel injection technology is a direct fuel injection into the cylinder, referred to as direct fuel injection, it is an imitation of a diesel engine, gasoline at high pressure, is injected directly into the cylinder (instead of the usual gasoline injection into the manifold). May be the best time to spray into the most suitable fuel into the cylinders, further improving power output and fuel economy of the engine, now there are many manufacturers use this technology on their car engine, such as Volkswagen FSI engine, the latest BMW 760Li V12 engine with direct injection also way.
with respect to a gasoline engine but also a diesel engine injection several different ways:
The first large diesel engine with a diesel engine or a plunger-type pump, governor, automatic injector or the like in advance mechanically adjusting the amount of oil and injection advance angle. However, this method is a large error, slow response. Since the emergence of electronically controlled fuel injection, electronic control diesel engines have come into being. It can be used with an electronic fuel injection control method similar to easily realize the supply of fuel, injection timing and other needs precise control over the others work diesel engine.
Note plug old fuel pump bulky, you need to have each cylinder with a high pressure tubing, in a multi-cylinder (4-cylinder above) diesel engine will be very complicated, as the diesel engine in the automobile widely use, reduce the volume of the diesel engine has become the engineers of thorny issues, so the common-rail diesel engine was born, it is a high-pressure injection pumps instead of the traditional plug fuel pump, and a high-pressure pipeline with all injectors are connected together by precise control of the solenoid valve opening and closing time of each injector, not only saves space, but also can make the injection pressure coincide each cylinder.
appears now a new technique is superior to the common rail injection, called the pump nozzle, the pump is integrated in the nozzle, each nozzle is actually a high pressure fuel pump, directly to an atmospheric diesel pressure sprayed into the cylinder. It eliminates the need for a comparison in terms of common rail high pressure tubing, and connected to a common pressure pipe each injector, but also reduces the cost of injection pressure than the common rail technology, diesel spray more thoroughly, thereby improve combustion, to increase the power of the purpose of improving the exhaust gas.