Diesel engines use diesel fuel. Because the diesel's evaporability and fluidity are worse than that of a car, it is not possible for a diesel engine to form a combustible gas mixture outside the cylinder like a gasoline engine. The diesel gas mixture can only be formed inside the cylinder, that is, near the end of the compression stroke. The injectors inject the diesel into the cylinder. The diesel oil droplets are heated, evaporated and diffused in the hot air and mixed with the air to form a combustible hybrid power. Finally, they burn by themselves. Because of the compression ignition method, the diesel engine is higher in thermal efficiency than the gasoline engine, and due to the higher density of the diesel fuel, the fuel consumption in the constant speed driving conditions is much smaller (constant fuel consumption testing for constant speed driving conditions). It is an important experiment for the automotive fuel economy of automotive experimentation. The density of the formula is in the denominator position. Traditional diesel engines use diesel fuel injection pumps, fuel injectors, and governors to supply fuel to diesel engines. Due to the extremely short diesel engine mixture forming time, they only account for crank angles of 15°-35°. The composition is very uneven and changes over time, so there is a need for a good match for the diesel engine's fuel supply system. The traditional diesel engine completely completes this matching through the interaction between the machines, resulting in the appearance of black smoke and loud noise in the impression of everyone, and the advantage of diesel engine fuel economy is also buried. With the advancement of science and technology, especially when common-rail technology is successfully applied to diesel engines, the advantages of diesel engine fuel economy are immediately evident, and the ills like black smoke no longer exist. More and more vehicles are starting to use diesel power. In Europe, almost half of the vehicles have begun to use diesel power. In China, with the introduction of a large number of advanced diesel engines such as the Volkswagen TDI and Shuanglong XDi, domestic consumers have actually experienced the driving experience brought by advanced diesel power. After years of development and improvement, the electronically controlled injection system of diesel engines has evolved from the first generation of displacement control to the second generation of time control to the current pressure-time control, which is known as common-rail injection technology. As the third generation of electronically controlled injection technology of diesel engines, the common rail injection system has abandoned the traditionally used in-line pump system, and instead used a fuel pump to establish a certain hydraulic pressure and sent it to the common high pressure tubing in each cylinder (that is, we The common rail) is then fed with common-rail diesel fuel into the injectors of each cylinder. In this way, the injection pressure of the common rail diesel injection system has nothing to do with the amount of fuel injection, nor is it affected by the engine load and speed. It can arbitrarily change the pressure level according to the requirements, so that the emission of nitrogen oxides and particulate matter are greatly reduced. Compared with traditional mechanically controlled diesel injection systems, electronically controlled diesel injection has the following advantages: 1. The basic control information of the mechanical control injection system is the speed of the diesel engine and the position of the accelerator pedal. The electronic control injection system detects the operating status and environmental conditions of the diesel engine through many sensors, and the electronic control unit calculates and adapts the operating conditions of the diesel engine. Control the amount and then try it by the actuator. Therefore, the control is precise and sensitive. Moreover, when it is necessary to expand the control function, comprehensive control can be realized by simply changing the storage software of the electronic control unit. 2. The mechanical control of the injection system is often due to setting errors and wear and other reasons, and the second is the injection time error. However, in the electronically controlled injection system, the rechecking is always based on the basic signal of the crankshaft position, so there is no possibility of misalignment. These advantages are also destined to the third generation of common-rail diesel engines will have more powerful power and more economical performance. Turbocharger technology has been used on diesel engines for more than half a century, and is almost perfectly matched to diesel engines. Compressed air is compressed by turbocharging technology before entering the cylinder. , In order to increase air density and increase air intake. In this way, the engine output power is improved and the fuel economy of the vehicle is improved. As a traditional advantage of diesel engines, low-speed high-torque is unmatched by gasoline engines. With the adoption of new technologies, the power of diesel vehicles is insufficient, and the disadvantages of slower acceleration are also improved. Below we use the data to illustrate the problem. Compared with the blank words, the data is more convincing. For example, with the 2.7LXDi diesel engine, Leicester 2 broke out at 121 rpm with a maximum power of 121 kW, and at 2400 rpm it could burst out with a maximum torque of 340 Nm, and the displacement was the same as the 2.7-liter petrol Toyota Prado with a maximum power of 120 kW. However, when the maximum power was reached, the engine speed had reached 5,000 rpm, and the maximum torque was 246 Nm at 3,800 rpm. From the data, it is not difficult to see that the Pratt 2 diesel engine is used in all data because of the use of the Prado engine gasoline engine, and the maximum power and maximum torque burst speed is much lower, which guarantees acceleration The capability also guarantees good fuel economy. Driving the diesel version of Leicester 2 can be said to be overkill on the highway, but it is also able to take the lead off the parking line during the start. As an SUV, off-road capability must be given priority, and the low-speed, high-torque characteristics of diesel engines are more suitable for off-road vehicles - climbing, getting out of difficulty, and easy to complete. In terms of fuel economy, 10 oils are sufficient to feed Saturate it. The number of diesel SUVs in the Chinese market is not large, but it is not small, but most of them are concentrated on low-end SUVs. The technology is backward. Even if common rail technology is used, the ultimate of common-rail technology is not used. It has been hovering around 70kW, but the high-end SUV basically does not sell the diesel version of the Chinese domestic market, because those high-end technical equipment can't even adapt to the harsh diesel quality in China. In contrast, Ssangyong diesel engine technology and adaptability Sexuality has reached a very good balance, can be described as the leading model of domestic diesel SUV. It is believed that with the continuous advancement of technology and the transformation of public awareness, more and more diesel SUVs like the Ssangyong series will enter our daily lives.
In the aftermath of the economic crisis, the oil crisis and other waves of crisis, a diesel SUV can enable everyone to fully enjoy the off-road fun while responding to the country's call to build a conservation-minded society. Why not?