What does the carburettor do?
The structure of the gasoline engine includesequipment such as carburetor. It should be noted that the engine itself does not work to prepare fuel for use, but it is prepared by the carburetor. In order to understand what a carburetor is, you need to know its types and general definition. The carburetor is an engine attachments that prepares a fuel mixture injected into engine cylinders for subsequent ignition. As a rule, the carburetor is located on top of the engine.
Carburettors are usually divided:
- By location of cameras:
- Horizontal (used mainly for racing cars).
- Vertical (used in most cars).
- By the presence of the float chamber:
- With the float chamber (complex carburetors, which were previously used in aviation).
- With a float chamber (used in most cars).
- By number of cameras:
- Multi-chamber (used in modern cars).
In turn multi-chamber carburetors divideinto two types. In the first type, the main and additional chambers are switched in series using a transition system, when the volume of the mixture being created is insufficient. In the carburetor of the second type, all cameras operate synchronously.
Now it is worthwhile to consider in detail how it workscarburetor. Its main function is to mix in the required ratio of gasoline to air. Most modern cars use the fuel injection method, because it is the most efficient and economical. However, some models of cars and small devices such as ATVs, lawn mowers use a carburetor because of the simplicity and cheapness.
Basic elements of the carburetor
The basic elements of the simplest carburetor are:
- The air channel. It is the basis of the carburetor and is a hole that provides air to the engine pipeline.
- Air damper. It is necessary to increase the speed of the air flow.
- Spray. It is into it through the jet and fuel from the float chamber.
- Camera. The required level of fuel in the carburetor is constantly supported by the float chamber.
Principle of carburettor operation
The flow of air quickly passes through the airchannel, which is necessary for spraying fuel or for mixing air with fuel. It should be noted that in the float chamber, which contains fuel, the pressure is atmospheric, and in the air channel - discharged. It is because of this difference in pressure that the fuel rises into the air channel, passing through the jet and the nebulizer. Then a thin jet of fuel penetrates into the air flow from the atomizer and is sprayed onto many small droplets. Thus, a combustible mixture is formed, which then flows into the engine cylinders through the intake manifold. In the event that the air damper is open, the air speed will increase. In the diffuser, the rarefaction increases with decreasing pressure, in connection with this, a large amount of fuel through the atomizer enters the air channel, thereby causing an increase in engine speed.
From the above it becomes clear what the carburetor is for. In fact, the preparation of a combustible mixture - this is the direct purpose of the carburetor.
Spraying of fuel
The process of atomization of fuel means fragmentationdrops of fuel into smaller parts. It should be noted that high-quality spraying is essential in order to reduce the toxicity of exhaust gases. It is achieved in two ways:
- Air is injected into the jet of fuel, which creates turbulence, which in turn breaks up into a small part a continuous jet.
- This method consists in installing at the point of maximum airflow velocity of the fuel outlet, which causes the fuel to be broken into fine dust.
It is important to note that the carburetor shouldSpray the fuel, not evaporate it. As for evaporation, it should already occur in the intake manifold, as well as the engine cylinder. Especially for this, the intake manifold is heated. This is done in order to reduce the condensation of fuel on the walls and improve evaporation. Most often, the heating is carried out using the engine coolant. It flows through the water channels of the collector, in rare cases - through the carburettor body itself and the throttle body.
Basic functions of the carburetor
So, in order to better understand what the carburettor does, it is necessary to consider in detail its basic functions in action:
- Introduction to the air flow of fuel, spraying it and partial evaporation. This is the initial stage of the mixture formation.
- The resulting mixture enters the intake manifold and engine cylinders, while continuing to evaporate the fuel.
- The dosage of fuel is carried out in accordance with the load and speed conditions of the engine operation.
- The amount of mixture varies depending on the mode of operation of the engine.
In addition, the carburetor should always ensure reliable starting of the engine, both cold and hot, engine operation at elevated temperatures, as well as a rapid change in the composition of the mixture.
Now you know what the carburettor does, inNow any self-respecting driver should know how his car works. Sometimes it happens that on the road there was a breakdown, a driver who has no idea what a carburetor is, can not cope even with the most elementary failure. Often in the service centers of the master "bred" inexperienced car owners for money, while knowing the elementary principles of the work of your "iron friend", you can fix it yourself.