Eaton Char-Lynn Motor , Diesel Motor Technology Development
Since the evaporability and fluidity of diesel are worse than those of automobiles, it is impossible for a diesel motor to form a combustible mixture outside the cylinder like a gasoline motor. The mixture of the diesel motor can only be formed inside the cylinder, that is, near the end of the compression stroke. The injector sprays diesel into the cylinder. The diesel oil droplets are heated, evaporated, diffused in the hot air, and mixed with the air to form a combustible hybrid, which eventually burns itself.
According to the Eaton Char-lynn Motor , the diesel motor is higher in thermal efficiency than the gasoline motor due to the ignition mode, and because of the high density of the diesel itself, the fuel consumption in the constant speed driving condition is much smaller (equal speed). The test of fuel consumption in working conditions is an important experiment in the fuel economy of automotive experiments. The density is in the denominator position. The traditional diesel motor supplies fuel to the diesel motor through the fuel injection pump, the fuel injector and the governor. Since the diesel motor mixture gas formation time is extremely short, only the crank angle of 15°-35° is occupied, and the mixture gas in the combustion chamber is mixed. The composition is very uneven and changes over time, so the fuel supply system of the diesel motor needs to have a good match. The traditional diesel motor completely completes this match through the function of the machine, which leads to the appearance of black smoke and loud noise, and the fuel economy advantage of the diesel motor is also buried.
With the advancement of technology, especially when the common rail technology is successfully applied to diesel motors, the advantages of fuel economy of diesel motors are immediately reflected, and the ills such as black smoke no longer exist. More and more vehicles are starting to use diesel power, and in Europe, almost half of the vehicles are already using diesel power. In China, with the entry of a large number of advanced diesel motors such as Volkswagen TDI and Ssangyong XDi, domestic consumers have experienced the driving experience brought by advanced diesel power.
After years of development and improvement, the diesel electronically controlled injection system 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 the common rail injection technology. As the third generation of diesel electromechanical control injection technology, the common rail fuel injection system abandons the traditional in-line pump system and replaces it with a high pressure oil pipe that is supplied to each cylinder by a fuel pump to establish a certain oil pressure (that is, we Said common rail), and then the diesel fuel is sent to the injectors of each cylinder by the common rail. In this way, the injection pressure of the common rail diesel injection system is independent of the fuel injection amount, and is not affected by the motor load and the rotational speed. The pressure level can be arbitrarily changed according to requirements, so that the nitrogen oxides and particulate matter emissions are greatly reduced.
Compared to 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 motor and the position of the accelerator pedal, while the electronically controlled injection system detects the operating state and environmental conditions of the diesel motor through many sensors, and the electronic control unit calculates the operating condition of the diesel motor. 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, it is only necessary to change the storage software of the electronic control unit to realize integrated control.
2. The mechanical control injection system is often due to setting errors and wear, etc., and the second is the injection time error. However, in the electronically controlled injection system, the re-inspection is always performed based on the basic signal of the crankshaft position, so there is no possibility of occurrence of an offset.
These advantages are also doomed to the third generation of common rail diesel motors will have more powerful power and more economical performance.
Compared to the long-delayed electronically controlled common-rail injection technology, turbocharging technology has been used on diesel motors for more than half a century, almost perfectly matched with diesel motors, pre-compressed air by turbocharging technology and then into the cylinders. , thereby increasing the air density and increasing the amount of intake air. In this way, the motor output is increased and the fuel economy of the car is improved.
As a traditional advantage of diesel motors, low-speed and high-torque are unmatched by gasoline motors. With the use of new technologies, the disadvantages of insufficient power and slow speed of diesel vehicles are also improved.
Below we use data to illustrate the problem, the data is more convincing than the blank words. For example, the Rest 2 with a 2.7LXDi diesel motor has a maximum power of 121 kW at 4000 rpm, a maximum torque of 340 Nm at 2400 rpm, and a maximum displacement of kW of 2.7 L gasoline Toyota Prado. However, the motor speed has reached 5000 rpm at the time of the maximum power, and the maximum torque is 246 Nm at 3800 rpm. Through the data, it is not difficult to see that the Lester 2 using the diesel motor must be based on the Prado of the gasoline motor, and the maximum power and maximum torque burst are much lower, which guarantees the acceleration. The ability also guarantees good fuel economy. Driving the diesel version of Rest 2 on the highway can be said to be easy, and in the start process can be the first to rush out of the parking line. As an SUV, the off-road capability is definitely in the first place, while the low-speed and high-torque characteristics of the diesel motor are more suitable for off-road vehicles – climbing, getting out of sleep, and easily done, and in terms of fuel economy, 10 oils are enough to feed Fill it up.
In the face of a wave of crises such as the economic crisis and the oil crisis, a diesel SUV will allow everyone to fully enjoy the off-road fun while responding to the call of the country to build a conservation-oriented society. Why not?
Diesel SUVs in the Chinese market are not too many, but not too small, but most of them are concentrated on low-end SUVs, and the technology is backward. Even with the common rail technology, the common rail technology is not fully utilized. It has also been around 70kW, and the high-end SUVs basically do not sell diesel versions to the Chinese domestic market, because those high-end technical equipment can not adapt to the poor domestic diesel quality, in contrast, the Ssangyong diesel motor is technically and adaptable. Sexual aspects have reached a good balance, can be described as the leading model of domestic diesel SUV.