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. Diesel engines with compression point
Fire, using high temperature air ignited diesel fuel, produce power.
Intake stroke
Exhaust valve closing and intake valve open. When the piston down the row from the TDC, only in the intake manifold of the air sucked through the intake valve cylinder, the time and no fuel
Into the cylinder.
Compression stroke
After the intake stroke, and when the piston from BDC started rising, the intake valve is closed and stop into the air. Increase in piston pressure and temperature, while it began to increase
. In diesel engines, compressed air must be heated until it reaches the ignition temperature of above.
Acting trip
When approaching the end of compression stroke, the fuel nozzle means to spray emitted by the heated compressed air is being atomized fuel will ignite. In this result, the cylinder
The pressure will increase rapidly and push the piston down, this thrust into the power to turn the crankshaft production.
Exhaust stroke
After the end of the combustion process, and when the piston just down the road close to the next point, the exhaust valve will open. When the piston up again And when will exhaust through the exhaust valve, exhaust manifold
And the exhaust muffler exhaust.
However, diesel engines, diesel fuel, the viscosity ratio of gasoline, which is difficult evaporation, and its spontaneous combustion temperature is lower than gasoline, so the formation of flammable mixture and the ignition with
Gasoline different.
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 engine speed changes
Technology, can not do the best under all speed oil 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, the system in each spray
Oil cooler through their high-pressure tubing and tubing connected to the public for the public for the tubing to the injector to play the role of hydraulic accumulators. Work, high pressure oil pump to high pressure of fuel delivery to the public
Total 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 with the engine oil pressure switch
The phenomenon of rapid change. The main features of the following three areas:
1, the fuel injection timing and 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; while diesel
Speed generally much lower than gasoline engines, torque than gasoline, but its quality and 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 engines was.
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