The main elements of the power system of diesel engine

The system of fuel supply is a major part of diesel engine. This system provides the necessary fuel supply pressure in the combustion chamber. The quantity of fuel into the chamber in the required amount at the right time. This article will talk about the main elements of the power system of diesel engine. From the fuel tank, through the boost pump low pressure fuel enters the high pressure fuel pump, which in turn distributes diesel fuel on highways hydro jets cylinders. Such a distribution takes place in an appropriate manner and the necessary portions of the fuel. High-pressure fuel injectors are opened, while lowering - are closed. High pressure pump (injection pump) - the basic elements of power systems and diesel engines are available in two types: distribution and inline multi-plunger. In-line pump supply system of diesel engine has separate sections, ranging in number and whose number corresponds to the number of engine cylinders. Each section is equipped with a sleeve with the plunger. Camshaft receives the rotation from the engine and actuates the plunger. Fuel injection pressure depends entirely on the speed of crankshaft. Such pumps work very noisy and do not meet modern requirements for the protection of the environment, so the inline pumps are virtually no sets. Distribution systems, high pressure pumps supply diesel engines, compared with in-line pumps, fuel is injected under higher pressure. Exhaust from a car with this type of fuel pump is less toxic and regulatory standards. On the mode of operation of the engine depends on the pressure in the fuel system, which supports this mechanism. The system of distributing high-pressure pump equipped with a plunger, which pumps, and distributes the fuel injectors on the engine cylinders. Pumps distribution type is functioning perfectly at high speeds and produce high-quality distribution of fuel in the engine cylinders. In addition, this mechanism is relatively compact in its dimensions. During operation of the distribution of pumps only use high quality fuel as well as in precision elements are very small gaps, but only parts of the system lubricated by fuel. In connection with the tightening of legislation on environmental requirements, manufacturers of diesel engines have begun to improve the fuel supply system. It is obvious that the mechanical fuel injection system can not cope with this task. In a mechanical system, the pressure of the fuel depending on load and engine speed. If the engine light load, the pressure of the fuel into the combustion chamber becomes smaller, which leads to subsidence of large drops of fuel on its inner surface. This leads to a decrease in combustion efficiency and fuel mixture to the higher content of harmful compounds in exhaust gases. To reduce the amount of harmful compounds in the exhaust, it is necessary that the entire air-fuel mixture burned in the combustion chamber, the shortest time. To achieve maximum results, you must determine the most accurate time and dose of injection. To do this you need to install an electronic control system of fuel supply and to maximize pressure fuel injection. By increasing the injection pressure depends on the quality of mixing fuel with air. The ideal ratio of fuel and air mixture when mixed results in its complete combustion, and, correspondingly, to reduce formation of harmful compounds in exhaust gases. To achieve this result, which will lead to increased pressure throughout the regular fuel system and fuel injection pump will not work. It's all about the "wave hydraulic pressure, which is formed on the whole interval way in fuel-wire. Wave power increases with increasing pressure, so eventually the pipeline simply collapse. Exact dosage of fuel injection in the mechanical system will not be possible to achieve. In the process of development of systems improvements supply diesel engines and their basic elements, was created two types of fuel injection system of diesel engines: The first type has a combined unit in which the basic elements of design - piston pump and nozzle form a single mechanism. This combined site is located at the head of the engine block for each cylinder. Through pushrod cam camshaft pump-injector driven. At the head of the block as there are channels for the drain and the fuel supply, thereby pump-injector can pressurize up to 2200 bar. The electronic control unit sends a signal piezoelectric and electromagnetic shut-off valves pump-injector, after which there is metered injection of compressed fuel. With the ability to pump-injector to work in a multi-pulse mode, is at first injection of small amounts of fuel, which significantly reduces the harmful compounds in the exhaust and alleviates the work engine. A disadvantage of this site is a direct relationship of injection pressure on engine speed. Such a technology injection diesel engine is quite expensive. The second type of injection pump runs on the fuel line Common Rail. Coming from the fuel it gets on the nozzle and the team the electronic control unit is injection. To meet the requirements of Euro 3 and 4, exhaust systems, engines have to equip catalysts and particulate filters. Pressure fuel injection system Common Rail does not depend on load and engine speed. Fuel pump in the power system of diesel engine is only responsible for the creation of high pressure in the pipeline. In contrast to the classical injection pump does not dose the amount of fuel and does not regulate the injection time. The power supply system of diesel engine Common Rail consists of the following main elements: fuel pump, battery, high-pressure injector kit, connected with a ramp and an electronic control unit. Regardless of engine speed and sequence of injection into the cylinders, the control unit maintains a constant pressure (1600 - 2000 bar). Work injectors controlled by an electronic control unit. He also calculates the optimum time and duration of injection on the basis of the data, which come at him from all kinds of sensors. Nozzles are electromagnetic or piezoelectric. The latter are more preferable, because they have a high response speed and accuracy of fuel metering. The system supplies the diesel engine Common Rail injectors operate in a multi-pulse mode, which allows for one cycle to produce up to seven injections. In the combustion chamber of a compressed fuel burns smoothly and completely, which leads to a significant reduction of exhaust emissions, and this, in turn, is very important for diesel engines.