No matter how the engine is designed, we should make a fuss about these two elements: air and fuel. To improve the power and torque of the engine, there is nothing better than improving the feed rate of the fuel supply of the engine. It is easy to increase the amount of oil, but difficult to increase the amount of air intake. Because air has specific physical characteristics, it is limited and can only be inhaled naturally. Therefore, once the exhaust turbocharging technology of diesel engine is transplanted to gasoline, it is a great success. about
The exhaust gas from the engine usually passes through the three-way catalytic muffler at high temperature and high pressure, and the exhaust pipe discharged outside the vehicle is used to pressurize the exhaust gas from the engine. The pressure of exhaust gas can push the turbine to rotate at high speed, and the exhaust gas passes through the turbine with connecting rod device. It can drive the rotation of compressed fresh air of the intake turbine and the intake turbine rotating at high speed in another position (the highest rotation speed can reach thousands of revolutions per minute), so that its density and high temperature and high pressure gas are greatly increased, which is not suitable for the combustion needs of the engine, so it is also cooled by the cooling device and then used by the engine. For example, it can greatly improve the power and combustion efficiency of a 1.8T turbocharged engine, which can be equivalent to a 2.3 naturally aspirated engine. Small displacement, high power and the highest level of engine technology.
Most importantly, when the maximum torque of the engine can be kept between 2 10 and 1750-4600 rpm, the platform structure of the engine torque curve, which is the engine design of the automobile, is also the biggest goal within the maximum torque range of the engine, making the driver feel inexhaustible in any speed range. This is the height that naturally aspirated engines in the world can't reach.
When you buy a car, you will often see many models, and then pass a T, such as Bora 1.8T Audi A6 1.8T Volkswagen Passat 1.8T and so on. Dealers will tell you that Model T is equipped with a turbocharged engine, which is more powerful than ordinary engines and has better fuel economy. What is the function of turbocharged engine? Why can he effectively improve the power output?
In fact, t turbo, this letter is the abbreviation of the word. The structure is simple, but the effect can not be ignored. As we all know, ordinary engines rely on the intake of the lower stroke piston and cylinder. Turbocharged engine compresses air first, and then enters the cylinder for inhalation. The density of air in the cylinder is higher, so the oxygen molecules in the unit volume also increase, so better intake can be obtained. The direct benefit of this is that the energy released during combustion increases, which will increase the power. This power is to improve a little. Usually, a computer is equipped with a turbocharged four-cylinder engine, and the boost value is high enough, so its power can be the output power of a six-cylinder engine. How is air compressed? Compressed air is sucked into the cylinder. What? (Above)
The related pictures of this theme are as follows:
The figure shows the working principle of a simple turbocharging system. Exhaust pipes of blue and red intake manifolds. From the arrow in the figure, it is easy to see that due to its high temperature and high pressure characteristics, the exhaust gas from the engine cylinder is introduced into the exhaust turbine through the exhaust pipe, which itself contains a lot of energy. This energy is enough to drive the exhaust turbine to rotate at a high speed of 100000 rpm. The turbine driven by exhaust gas rotates at the same speed by entering the intermediate shaft of the gas turbine, so it can compress a lot of fresh air and improve the air density. The natural science of gasoline is that in order to avoid the high-temperature heat release of compressed air in the cylinder, the first high-pressure air cooler must be introduced for subsequent cooling air cooling to allow safe combustion in the cylinder.
The related pictures of this theme are as follows:
The picture shows the gas structure of turbocharging. It is easy to see the arrow from the working process of turbine gas. Here, the key mechanism is the turbine shaft of the lubrication system. Don't underestimate the turbine blades, bearings and working environment between the two. It is not difficult to imagine that the exhaust temperature of the engine is very high. Under such high temperature conditions, its rotating speed is 654.38+0 million per minute, which puts forward high requirements for its high temperature wear resistance. Specifically, in this bearing box, there are two holes, through which part of the oil is absorbed, so that the intermediate shaft can be suspended on the oil film and rotate at high speed, ensuring its better reliability and durability.
The diameters of turbochargers are usually classified into different grades according to the requirements. The larger the diameter of the steam turbine, the stronger the ability to compress air, so the higher the pressurization value, the greater the power generated by the engine. However, the increase of supercharging value cannot be infinite. Due to the greater the pressurization value, the heat released into the air after compression is relatively limited. Because of the refrigeration capacity of air conditioner, the hot air in the cylinder can easily lead to natural gasoline, which can not only improve the power of the engine, but also attenuate it. Serious or even blown up, causing the whole engine to be paralyzed. The value of turbocharger determined by calculation and experiment can be changed at will. ,
Turbochargers can significantly improve the power of cars, so why not all cars are equipped with them? Yes, of course there are reasons. The moving part of the turbine we can think of has a certain mass, and then it takes a little time to accelerate from standstill to more than 1000000 rpm. As we all know, whether the engine is high-speed or low-speed, the requirements for the speed of the intake turbine are low. If the hard disk accelerates, then suddenly a large feed speed is needed to increase the power output of the engine. It takes some time for the turbine blades to increase the rotating speed and increase the air intake. Although the time is not long, there will be obvious lag when driving. This phenomenon is called turbo lag. The driver who accelerates sharply will obviously feel bloated at the start and low speed, but when the engine speed rises, he will suddenly feel a surging power. This is why people often say that turbocharged engines have enough stamina.
Audi TT dual turbocharging solution to solve the lag problem. The so-called double turbocharger is installed on the engine, and there are two turbochargers, which have smaller diameter and lower supercharging value and are used when the engine speed is low; In a high-value turbocharger with a larger diameter, it starts at a higher engine speed. This can alleviate the phenomenon of turbine lag to some extent, but they cannot eradicate the problem. However, if the car is equipped with an automatic transmission, the unpleasant feeling caused by the short-term turbine lag will absorb the hydraulic torque converter of the automatic transmission, and the driver will hardly notice it.
On the positive side, due to the lag and common problems of turbocharging technology, many enterprises have not used it yet. For example, Honda, BMW and Ferrari, which emphasize the response of engine factories, have you considered the application of turbocharging technology? Turbocharging has a significant advantage, that is, it can make both small-displacement engines and large-displacement engines have power performance, while only small-displacement engines have volume. Porsche turbocharging technology is the representative of introducing high-performance sports cars. Porsche 9 1 1 Turbo is a designed rear engine with a small engine compartment, which simply cannot tolerate a single 8-cylinder engine. In order to achieve the effect of eight-cylinder engine power, the output power of the turbocharger installed in the six-cylinder engine of the aircraft is 420, which is equivalent to the power level of the eight-cylinder engine.
It is a fact that dealers often use turbocharged engines to save fuel than ordinary engines. But many people think that 1.8T engine is more fuel efficient than 1.8 engine. Why is this? Actually, saving fuel is relative. Turbine-driven engine exhaust gas turbine, the movement of the turbine, without any loss, the power of the engine, on the contrary, compression exceeds the ordinary intake. Therefore, the working efficiency in the engine is improved. This engine with the same displacement uses less oil and is more efficient than Model T engine. So you have to compare fuel consumption with displacement, and take the considerable power ratio of the car, which is undoubtedly turbocharging, which is more economical.
In Japan, many manufacturers like to use turbocharging technology. Fuji series and Mitsubishi EVO are typical examples. In Europe, after Sweden, the first turbine was introduced into cars to test Wal-Mart's turbocharging technology. There are also two warehouses in Germany, such as turbocharged, RS6, 9 1 1TURBO models represented by Audi and Porsche. The world's leading high-performance turbocharged engines manufactured by these car factories!
The turbocharging pump that was first used on the plane was in the car, and then it gradually evolved into
The working effect is to increase the inconvenience of original accessories under the output power of the engine and make the engine more dynamic! The use of turbocharger pump has its own defects, because it mainly relies on the exhaust gas discharged from the engine by the output power of electric drive, so its working environment is relatively bad. In addition, the working temperature is high, which is very important. Both popular models are oil-heated. This is why when many pumps need to be replaced in the later stage, they smell the oil in some exhaust gas more or less, because the oil-sealed turbocharger pump has been damaged, the sealing oil that can't work is not sealed, and the oil will flow into the pump to ventilate together.
The new driver is not careful during driving, and even doesn't know the consideration of turbocharger pumping oil. The following is a simple explanation:
A cold start of one liter requires the driver to start the engine when the engine is idling. When the engine is in a cold state for at least 30 seconds, you can move it to avoid the engine lubricating oil high-pressure turbo pump from getting stuck when the engine speed is too high during cold start. Turbocharger is lubricated by oil pump through special pipeline pressure, and it is eager to start the moving vehicle during cold start. The speed and load of turbopump increase rapidly and the oil pressure is low. Its turbocharger and water pump are stuck.
Don't turn off the engine immediately when driving at a high speed, because the engine is still rotating at a high speed under the inertia of the turbocharger pump. The lubrication of turbine shaft depends on the working completion time of oil pump. If the engine is turned off, all lubrication will stop immediately. The failure of high-speed rotating turbine shaft is due to lack of lubrication. The correct operation method is to end the high speed after the first idle period, stop for about 90 seconds, and then turn off the engine.
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