Turbine and supercharger technology introduction: Dehydrated Red Beet,Dehydrated Red Beets For Snacks,Dehydrated Red Beet Powder,Dehydrated Red Beet For Baking Xinghua Lvwei Foods Co.,Ltd , https://www.lvweifoods.com
With the continuous improvement of social productivity and technology, people's demands for transportation are constantly improving. How can a small-displacement engine explode the power of a large-displacement engine? Supercharging technology is one of the most effective methods. The air intake supercharging technology we currently use on the vehicle engine is the first source of the aircraft's high-altitude flight. We all know that the general engine uses the cylinder piston to move down to form a vacuum and inhale the air to achieve the intake process. This is the so-called process. Naturally aspirated engine. The natural inhalation method achieves the intake action by "passively", so the air intake efficiency is not high in the high air, which greatly affects the function of the engine. In order to improve the engine intake efficiency, a pressurized intake air technology was invented.
Turbochanger and superchanger are two different ways of intake boost, the main difference being the drive mode of the supercharger. The earliest superchargers were all supercharged. They were called superchargers when they were first invented, and later they were invented to distinguish the two. At first, the turbocharger was called Turbo Supercharger, and the supercharger was called Mechanical Supercharger. Over time, the two were simplified to Turbocharger and Supercharger respectively. The Germans called the supercharger Kompressor because of the German language, which is why the Mercedes-Benz 1.8L supercharged engine is called 200K, and the German word Kompressor is also printed on other German cars equipped with superchargers. on.
Turbocharging is driven by the exhaust gases from the engine. The turbine consists of two parts, one is the fresh air booster end (compressed pump wheel), the other part is the exhaust gas drive end (exhaust gas turbine), there is one impeller at each end, and there is a leak between the two sides of the turbine on the same shaft. The pressure gate is located on the side of the exhaust turbine. When the compression turbine pressure is too high, the pressure pushes the trigger to open the valve of the exhaust turbine to lower the air pressure to prevent over pressurization.
The bearing of the turbine axle is designed for the bearing inside the bushing bushing and can be divided into ball bearings and floating bearings. The rotational power of the turbocharger impeller comes from the exhaust. The exhaust gas drives the turbine, and on the other side of the turbine, the blades compress the air. The turbocharger housing is made of nickel, chrome and silicon alloy and the shaft is made of chrome and molybdenum alloy. More importantly, the turbocharger works under high temperature and high speed conditions. To ensure its normal operation, the oil and coolant are introduced into the turbocharger to ensure effective lubrication and cooling, and improve working conditions. .
Exhaust gas discharged from the engine with high temperature and a certain pressure enters the supercharger, and the impeller of the propeller shaft rotates at a high speed of tens of thousands or even hundreds of thousands of revolutions per minute. At idle speed, the impeller rotates at 12,000 rpm. When the load is applied, the impeller speed can exceed 135,000 rpm. Ordinary bearings cannot withstand the high temperature and wear caused by such high speed, so the lubrication and cooling of the oil in the turbocharger system is very important. Diesel engines are also equipped with a number of turbocharged systems, and the maximum boost value of diesel engines is generally higher than the maximum value of gasoline engines. It is also for the good heat dissipation needs of the turbocharger. Generally, a vehicle equipped with a turbocharger requires an idle speed before the flameout.
Turbocharger A/R value: A/R value is often indicated in the turbocharger sales book of the modified market to express the characteristics of the turbine. A is the meaning of Area, which refers to the blade turbine. The cross-sectional area at the narrowest point of the side inlet that receives the exhaust gas, R is Radius, which refers to the distance between the center point of A (cross-sectional area) and the center point of the turbine body, and the ratio of the area to the distance between the two center points. A/R value.
The smaller the A/R value, the smaller the inlet and the lower the inertia of the turbine blade, the higher the flow rate, the better the low-turn reaction, and the less the turbo-lag effect. On the contrary, the larger the A/R value is, the larger the inlet is, the blade inertia is higher, the low-turn reaction is slower, the turbo lag is more obvious, but the performance is much stronger at high turn. In simple terms, the turbine with a higher power output output can achieve an A/R value of about 0.7, while a turbine with a low torque output has an A/R value of about 0.2. Porsche's VTG variable turbine geometry blade technology achieves different turbine characteristics by varying the turbine's A/R value.
★The structure and working principle of supercharger:
The driving force of the supercharger compressor comes from the crankshaft of the engine. Generally, the crankshaft pulley is connected by a belt, and the torque of the crankshaft is indirectly driven by the turbocharger to achieve the purpose of supercharging. Depending on the structure, there are many types of supercharging, including vane, roots, and Wankle, and piston movement was first considered a supercharger. Today, the most widely used Rhodes supercharger is the most popular modification. The Lodz supercharger is available in two-bladed and three-bladed rotors. It is currently more common with double-bladed rotors. It is constructed with two dome-shaped rotors in an elliptical housing with minimal clearance between the rotors. Instead of being directly connected, the rotating shaft of one of the rotors is coupled with the driven pulley by a helical gear. The pulley of the rotor shaft is equipped with an electromagnetic clutch. When the boosting is not required, the clutch is released to stop the boosting, and the clutch is Computer control to achieve fuel-saving purposes.
Advantages of supercharging: In addition to obtaining supercharging at low speed, the supercharged power output is also proportional to the crankshaft speed, that is, the throttle response of the supercharged engine increases with the increase of the rotational speed. Therefore, the operation feeling of the supercharged engine is very similar to the natural inhalation, but it can have a large horsepower and torque. The disadvantage is that the power of the engine itself is always lost, and the efficiency is not high at high speed.
Therefore, Volkswagen's GOLF 1.4TSI uses TSI dual boost technology. One engine is equipped with two superchargers at the same time, taking advantage of the two boost modes, so that the 1.4 engine can have 2.0 engine power. Simply speaking, the supercharger is used to boost the engine when the engine speed is low, and the throttle response is improved. When the high speed is used, the turbocharger is used to increase the boosting efficiency, but the manufacturing is complicated and the cost is high.
The last thing to say is that no matter the supercharging method, the supercharged air should be sent to the intercooler to cool down (the boost is equal to the work on the air, and the temperature will rise to 80 degrees when the pressure is increased to 1 bar). Left and right, the air volume will increase after the temperature rises, and the air quality entering the combustion chamber at the same volume will decrease, which is unfavorable for the supercharging, so the intercooler should be used for cooling.) The excessively high air pressure will be at the Blow-off Wastegate. Let go, so sometimes we can hear a "beep" venting sound on the turbocharged car, and the pressurized air is finally sent to the combustion chamber.
Regardless of the type of supercharging, the supercharged air is sent to the intercooler to cool down (the boost is equal to the work on the air, the temperature will rise to about 80 degrees when the pressure is increased to 1 bar, and the air rises after the temperature rises. The volume will increase, the air quality entering the combustion chamber will decrease in the same volume, which is unfavorable for the supercharging, so it should be cooled by the intercooler.) The excessive air pressure will be released in the Blow-off Wastegate, so sometimes we You can hear the "squeaky" sound on the turbocharged car, and the pressurized air is finally sent to the combustion chamber.
In today's car market, more and more models use turbine or supercharged technology to improve vehicle performance. As emission standards become more stringent, automakers must not only meet environmental requirements, but also meet customer needs. To ensure enough driving pleasure. Supercharger technology is designed to reduce emissions and improve fuel economy without sacrificing driving pleasure.