The working process of diesel engines with gasoline engines as a matter of fact, each work cycle has gone through the intake, compression, for power, four stroke exhaust. However, diesel engines, diesel fuel, the viscosity than gasoline, which is difficult evaporation, while its low ignition temperature is higher than gasoline, so fuel mixture formation and ignition with gasoline in different ways. diesel engine in the intake stroke of the inhaled pure air. Near the end of the compression stroke, diesel fuel injection pump through the oil pressure up to 10MPa or more, through the injectors spray into the cylinder, in a very short time and high temperature compressed air mixing to form a combustible mixture.
As the diesel engine compression ratio (usually 16-22), so the end of the cylinder compressed air pressure up to 3.5-4.5MPa, while temperatures as high as 750-1000K (and gasoline engine hybrid gas pressure at this time for 0.6-1.2MPa , to a temperature of 600-700K), much higher than the spontaneous combustion temperature of diesel. Therefore, after the diesel injected into the cylinder, mixed with air in a very short time immediately after self-ignition combustion. Rapidly rising pressure inside the cylinder to the 6-9MPa, the temperature has risen to 2000-2500K. In the high-pressure gas driven by the crankshaft driven piston downward movement and rotation for power, the same exhaust into the atmosphere through the exhaust pipe.
ordinary diesel engine camshaft driven by the aid of high-pressure pump diesel fuel delivered to each cylinder chamber. This approach to oil changes with changes in engine speed, engine speed can not do all the best fuel supply. It is now more widely used in electronic control common rail diesel injection systems can be better solved the problem. jet common rail fuel injection system from the high-pressure pump, the public for the tubing, injector, electronic control unit (ECU) and a number of pipeline pressure sensors in the system each injector through their high-pressure tubing and the public for tubing connected to public
For the tubing to the injector to play the role of hydraulic accumulators. Work, high pressure oil pump to high pressure fuel delivery to the public for the pipeline, high pressure pumps, pressure sensors and ECU closed loop composed of the work of the public for the hydraulic tubing to achieve precise control, completely changed the oil pressure with engine speed change phenomenon . The main features of the following three aspects: 1, injection timing and fuel metering completely separated, the process of injection pressure and injection time control by the ECU. 2, can be adjusted according to the working conditions of the engine cylinder injection pressure, start of injection, duration, and thus the pursuit of the optimal control point fuel injection.
3, to achieve a high injection pressure, and to achieve pre-injection diesel. compared to gasoline engines, diesel engines with low fuel consumption (average 30% lower than gasoline) and diesel prices low, so fuel economy is better; the same time the engine speed generally much lower than gasoline engines, torque than gasoline engines large, but the quality of a large, noisy work, manufacturing and maintenance costs high, and worse emissions than gasoline. But with modern technology, diesel engine, these drawbacks are gradually being overcome, not the high-level cars now have started using diesel-powered
Machine has. For the second rocket engine and four-stroke engine. Two-Stroke Engine: All engine crankshaft rotates one turn, that under the reciprocating piston two stroke following the completion of a working cycle of the engine. Four-stroke Engine: All engine crankshaft rotates two turns that reciprocating piston moving up and down while moving the completion of a working four stroke engine cycle
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