What are the functions of turbocharging

The purpose of supercharging is to increase the output power and torque of the engine without increasing the engine displacement, so that the car has better power performance. There are two main types of supercharging technologies at present: supercharging and turbocharging, but the principles of the two are different.

The full name of turbocharging is exhaust gas turbocharging, which is generally represented by "T". Turbocharging is a device that increases the pressure of the air flow in the intake pipe by pushing the rotor to rotate by the high-velocity gas coming out of the exhaust pipe. Increase the pressure of the airflow to allow more air, i.e. more oxygen, to enter the cylinder, so that the combustion will be more adequate and the power will be greater.

At both ends of the supercharger is a turbine on one side and a compressor on the other, and the waste device drives the blades to rotate and drive the compressor machine to work, so that it can deliver more air to the intake pipe faster and in larger quantities. The turbocharger relies on the function of high-speed exhaust gases, which are wasted in a normal engine. Thanks to its speed, the turbo press rotor can achieve very high speeds, even up to around 150,000 rpm.

But turbocharging has one of the biggest disadvantages, that is, there is turbo hysteresis: that is, at lower speeds, when the accelerator pedal is pressed, the engine will not have a large power increase, and it will not start to work until the speed rises to a certain extent (generally at 2500-3000 rpm), and the turbocharger will feel a sudden increase in power at this time, but this often affects the ride comfort of the car! Mechanical pressurization, on the other hand, is different:

Its rotor is not driven by the exhaust gases of the engine, but directly by a belt connected to the crankshaft of the engine, which is driven by the crankshaft of the engine. The crankshaft is the power take-off shaft of the engine, so that the supercharger not only increases the pressure, but also consumes part of the power, so the supercharging efficiency of the general supercharger is not high. However, the biggest advantage of supercharging is that there is no turbo hysteresis of turbocharging, so the supercharging effect of supercharging at low speed is more obvious, but the disadvantage is that its efficiency gradually decreases with the increase of speed, which is the opposite of turbocharging!

I'm a supercharger repairer, and one more supercharger has 30 horsepower, and it's fuel-efficient, and I remember that the supercharger needs to be maintained!

On the basis of not changing the engine displacement, the dynamic acceleration has been significantly improved, and there are two types: turbocharging and mechanical supercharging.

The main function of turbocharging is to increase the air intake of the engine, thereby increasing the power and torque of the engine and making the car more powerful. When an engine is equipped with a turbocharger, its maximum power can be increased by 40% or more compared to without a turbocharger.

Turbocharging is a technology that uses exhaust gases generated by the operation of an internal combustion engine to drive an air-compre ss or (air-compre ss or). Commonly used in automobile engines, turbochargers can increase the horsepower output of internal combustion engines by harnessing the heat and flow of exhaust gases.

The types of turbocharging include mechanical pressurization system (a belt connected to the engine crankshaft, and power is obtained from the engine output shaft to drive the rotor of the supercharger to rotate, thereby blowing the air pressurized into the intake air duct), air wave pressurization system (using the pulse air waves of high-pressure exhaust gases to force air compression); Exhaust gas turbocharging system (increase the air intake by compressing air, generally speaking, the engine power and torque after installing the exhaust gas turbocharger should be increased by 20%-30%), composite charging system (exhaust gas turbocharging and mechanical supercharging are used together, mechanical supercharging helps torque output at low speeds, but power output is limited at high speeds).

When an engine is equipped with a turbocharger, its maximum power can be increased by 40% or more compared to without a turbocharger. This means that the same engine can produce more power after being pressurized. Take our most common turbocharged engine, for example, after supercharging, the power can reach the level of the engine, but the fuel consumption is not much higher than the engine, on another level is to improve fuel economy and reduce exhaust emissions.

Photo by Wu Danling) @2019

The specific role of turbocharging: the use of exhaust energy to compress the intake air, and the high-density mixture into the combustion chamber to increase the output power, when the turbine uses the exhaust energy to rotate, the supercharger impeller installed at the other end of the shaft will be compressed intake air into the engine, there is also a mechanical turbocharger, which through the crankshaft, directly by the transmission belt to drive the compressor, increase the intake volume.

Turbocharging is well used in engines, and turbocharging can increase power and improve the performance of diesel engines.

When an engine is equipped with a turbocharger, the maximum power output can be increased by about 40% or more compared to the non-turbocharger. Turbo increases the daily use and maintenance of the engine is a bit more troublesome. Compared with naturally aspirated engines, turbocharged engines have stricter requirements for the working environment and maintenance.

With the exhaust gas turbocharger, the plateau diesel generator set is just as powerful.

Turbochargers are mainly composed of compressors and turbines. The exhaust gas discharged from the diesel engine enters the nozzle through the turbine shell and flows to the turbine blade in a certain direction, pushing it to rotate at high speed, driving the compressor impeller on the coaxial to rotate at the same high speed to produce siphon effect, the siphon principle is: the essence of siphon is generated because of gravity and intermolecular cohesion.

Fresh air is sucked into the compressor casing through the air filter, the speed and density of the air flow increase and the pressure increases through the diffuser, and the air flow energy through the compressor casing and the diffuser becomes static energy, and the pressure is further increased and enters the engine intake pipe, so as to achieve the purpose of air intake pressurization and increase engine power.

Due to the better combustion performance of the engine with turbocharger, fuel savings of 3%-5% can be achieved. Of course, there are advantages and disadvantages, the disadvantage of turbochargers is hysteresis, that is, due to the inertia of the impeller, the engine delay increases or decreases the output power.

The exhaust gas turbocharging system increases the air intake by compressing the air. It uses the inertia impulse of the exhaust gas discharged by the engine to push the turbine in the turbine chamber, and the turbine drives the coaxial impeller, and the impeller pressurizes the air sent by the air filter pipe to pressurize it into the cylinder.

If the supercharger can not be assembled on the matching engine, the role is also greatly reduced, the power of a turbine is directly related to the exhaust temperature and pressure of the engine, whether it is well matched but also to consider whether the choice of turbine flow is appropriate. It is also necessary to observe various data such as air consumption characteristics to maximize the advantages. The main performance indicator of an exhaust turbocharger is the air pressure rise ratio, known as the pressure ratio.

It is expressed as the ratio of compressor outlet air pressure pk to compressor inlet air pressure p1, i.e., nk = pk p1.

Generator manufacturer Dingbo power technicians told us that the performance of the diesel engine supercharger is broken, the engine power will be greatly reduced, there is no supercharging effect, and the exhaust heat dissipation of the motor will not be smooth for a long time. After the supercharger is damaged, the air will not be able to enter the combustion chamber sufficiently, and the power will drop by 30%, and the throttle power will not increase but only emit black smoke.

Photo by Pacific Automobile Network Q&A).