8 characteristics and benefits of diesel engine

In 1892, the German inventor Rudolf Diesel (Rudolf Diesel) invented the diesel engine and it has been more than 120 years. Diesel engines are used in various mechanical equipment. Do you know the characteristics, advantages and benefits of diesel engines?

1. The advantages of diesel engines are large output torque, high thermal efficiency, and good fuel economy.

2. The diesel engine is the same as the gasoline engine. Each working cycle also undergoes four strokes: intake, compression, power, and exhaust.

3. However, since the fuel used in the diesel engine is diesel, its viscosity is higher than that of gasoline, it is not easy to evaporate, and its ignition point is lower than that of gasoline. The mixture in the cylinder of the diesel engine is compression ignited, so the diesel engine does not need an ignition system.

4. When the diesel engine is working, air is sucked into the cylinder. When the air in the cylinder is compressed to the end, the temperature can reach 500-700°C and the pressure can reach 40-50 atmospheres. When the piston is close to the top dead center, the fuel injection nozzle of the fuel supply system injects fuel into the combustion chamber of the cylinder at a very high pressure in a very short time, and the diesel fuel forms fine oil particles, which are mixed with high-pressure and high-temperature air, and the combustible mixture burns by itself , The violent expansion produces explosive force, pushing the piston down to do work. At this time, the temperature can reach 1900-2000 ° C, and the pressure can reach 60-100 atmospheres. Therefore, the torque generated by the diesel engine is large.

5. Due to the high working pressure of the diesel engine, the relevant parts are required to have high structural strength and rigidity, so the volume of the diesel engine is relatively large; the manufacturing precision of the fuel injection pump and nozzle of the diesel engine is high.

6. In addition, the diesel engine works roughly and has high vibration and noise; diesel is not easy to evaporate, and it is more difficult to start cold at low temperature than gasoline engine. In addition, the power per liter index of a diesel engine is not as good as that of a gasoline engine (lower speed), and the emission of soot and particulates (PM) is more than that of a gasoline engine. Due to the above characteristics, early diesel engines are generally used in large and medium-sized trucks and related engineering vehicles and equipment.

7. With the development of diesel engine technology, a number of advanced technologies, such as direct injection, turbocharging, intercooling, electronic control, common rail and other technologies, have been applied to diesel engines, making the original shortcomings of diesel engines better. However, the advantages of diesel engines in terms of energy saving and CO2 emissions cannot be replaced by all heat engines including gasoline engines.

8. Nowadays, the application fields of diesel engines have become more and more extensive, and they are used in many fields such as trucks, pickups, SUVs, excavators, forklifts, generators, garden machinery, and agricultural machinery.