One article thoroughly understands the structure and principle of the turbocharged system

Auto Sharing with maintenance knowledge

The intake pressure of the engine has many forms, such as supercharged methods, air wave supercharged methods, and exhaust turbine supercharged.

The current commonly common is the exhaust turbocharged method. The exhaust gas turbocharger is actually an air compressor that increases the amount of air intake by compressing the air. It uses the exhaust gas inertial impulse discharged by the engine to promote the turbine in the turbine room. The turbine drives the impeller of the coaxial axis.

The typical turbocharger structure is shown in the figure below.

1. The cylinder head of integrated exhaust manifold

At present, the new national six engines basically use a cylinder head with integrated exhaust manifold. (IEM) The typical cylinder head of integrated exhaust manifold is shown in the figure below. img src = \”https://p3-sign.toutiaoimg.com/pgc- Image/821B4C8DCA1246B286E2D7EFBED~tplv- origin-gif.jpeg? 58558 &FROM = Article.pc_detail & LK3S = 953192F4 & X-EXPIRES = 1738724825 & X-Signature = Uoyqw0eiu7rjcdo9gy%2blbpwtyxg%3d \”/>

This cylinder cap of this integrated exhaust manifold is as follows:

(1) canceled The individual exhaust manifold has improved the integration, saving space, simplified the layout of the parts, the body\’s weight is reduced, and the fuel consumption and emissions will be improved accordingly. Track = \”15\”>

(2) During the cold start and heating process, the heat exchanges with the water cover of the cylinder cap, the cooling liquid has fast temperature, the engine is quickly heating, and the friction of internal components is reduced. , Backbuilding atomization, improved combustion efficiency, not only oil-saving, but also reduced pollutant emissions during the heating process. >

(3) When the engine reaches the heat machine state, or in the load running state, the exhaust gas temperature discharged by the engine is very high, and the overall temperature of the turbocharger will be very high. Heat, low density, and easily cause explosion. The pump pressure efficiency of the device will be improved accordingly. STYLE = \”Letter-spacing: 0.5px;\”> (4) canceled separately exhaust manifoldsIt also means that the length of the air path of the exhaust gas side turbocharger is shortened, and the response speed of the turbocharger will increase.

2. Dual flow road exhaust pipe road

The exhaust pipeline of the turbocharger adopts two pipelines. The gas method adopts a more advanced single -turbo twin tube technology. The two exhaust pipes of the turbocharger are shown below.

Most of the traditional common turbocharged engines use single turbine mono tube technology, all cylinder exhaust digest The pipe is gathered first, and then the turbine is blown into the turbine, which means that there is only one exhaust trail.

Taking the four-cylinder turbocharged engine as an example, the order of ignition is 1-3-4-2. If a exhaust pipe is used, the engine exhaust will inevitably cause gas The pulse resonance, that is, the excreted exhaust gas will \”fight\”, which will affect the exhaust efficiency between the cylinder and the cylinder body. If the two adjacent cylinder vessels are opened at the same time, the exhaust gas will return to the front cylinder, which will reduce its intake efficiency, and the total power of the next cycle will be affected. /p>

In order to eliminate the interference between the exhaust of each cylinder, the exhaust side of the cylinder lip is designed as two pipes, so that the ignition two adjacent cylinders are adjacent to two cylinders The exhaust pipes are separated by two or two (1 and 4 groups, 2, and 3 groups). In this way, the inlet exhaust of the two adjacent cylinders is not affected by interference, and the inlet and exhaust process of each cylinder is smoother, and then the exhaust process Improve the engine efficiency of the engine

Two pipelines on the cylinder lip side (below) and turbocharger Two pipeline docking of the exhaust side.mg src = \”https://p3-sign.toutiaoimg.com/pgc- Image/241982588d50417496bc7264cbe~tplv- origin-jpeg?_iz=58558 &FROM = Article.pc_detail & LK3S = 953192F4 & X-EXPIRES = 1738724825 & X-Signature = Ju60fx485uez9apf3wogoa2slxi%3d \”/>

p data-track = \”37\”> The data shows that the working efficiency of the single -turbo twin engine engine is about 7%higher than that of the single -turbo monotherapy engine, especially the transient acceleration performance is relatively obvious.

3. Electrical control exhaust door actuator

The turbocharger should work normally, except for the turbulent rotation of the turbine rotationAnd drive the pump wheel to pump pressure on the air intake side air, to achieve an air -voltage pressure, the pressure of the air -voltage pressure must be regulated to meet the design requirements of the target supercharged, and at the same time, the system prevent the system from excessive supercharging. The engine is damaged.

To this end a turbine cavity in the turbocharger The turbine is not impacted by the bypass, so as long as the opening of the waste gas bypassing valve is adjusted, the speed of the turbine can be adjusted, and the intake -side supercharged can be adjusted to the range of the target supercharged. The waste gas bypass valve in the turbine cavity is shown in the figure below.

For early turbochargers, it is generally controlled by pneumatic or vacuum. In contrast, the pneumatic method is more widely used. Its structural characteristics are to use a three -way two -bit solenoid valve (usually referred to as a supercharged control solenoid valve) to control a pneumatic actuator through air pressure. Linking valve linkage, so as long as the pipeline air pressure of the pneumatic actuator is controlled, the opening valve of the exhaust air bypass can be adjusted to regulate the engine\’s intake voltage.

turbocharger with aerodynamic performers is as shown below. Show.

At present, the exhaust gaseous crossbar valve of the turbocharger has been improved. It is a motor control method. This device is called an electronic exhaust corn or an electric exhaust air bypass valve actuator in some materials, as shown in the figure below.

The electric actuator of the exhaust gas bypass valve is actually a DC motor with position sensor. During the work process, the DC motor is controlled by the engine control module. The angle of the motor rotation is connected to the exhaust wirest valve through the connecting rod. The opening of the motor rotation is corresponding to the opening valve of the exhaust gas bypatient. Correct the closed-loop control process of the entire supercharged regulation. The appearance structure of the exhaust gas bypass valve electric actuator is shown in the figure below. img src = \”https://p3-sign.toutiaoimg.com/pgc- Image/e3732862e0496c92200ABD65CBC-tt- Origin-wegi.jpeg?_iz=58558 &FROM = Article.pc_detail & LK3S = 953192F4 & X-EXPIRES = 1738724825 & X-Signature = TKG6D6KWZPNPS0ZVMQNTV%2BIU3GM%3d \”/>

4. Inlet cross-pass valve

In order to make the turbocharger work normally, it is necessary to install a bypass valve between the pump wheel air intake and the air outlet pipeline to be used to use it in special operating conditions. High -pressure air leakage is released to prevent the stagnation of asthma and eliminating rapid acceleration. /span>

The intake cross-pass valve is an solenoid valve component that controls it by the engine control module. There are two forms. One is that the intake valve is directly installed in the turbocharger shell. The pump wheel cavity in the turbocharger shell has a shelter. The figure shows

<p class =\" pgc-IMG-CAPTION \"

Another layout form is to arrange between the pump air inlet and the air outlet tube A air pipe road, the air intake bypass valve is installed on this air pipeline, which is leaked by opening or closing. Form, as shown in the figure below

To sum up, the main role of the inlet bypass valve is to eliminate the stagnation after the acceleration. After the rapid acceleration is accelerated, due to the sudden shutdown of the throttle, the exit of the pump wheel and the throttle door The air pressure between the pumps will produce a braking effect, leading to the scream of turbine stagnation and the blocking of the exhaust, and even damaging the air intake -pipeline and electronic fostering. The method is that the engine control module recognizes the rapid acceleration of the acceleration according to the accelerated pedal itinerary and rate. At the end of the rapid acceleration, open the intake crossbar valve to leak the supercharged gas, thereby eliminating these adverse factors.

5. Improving pressure sensor Strong>

\”The pressure sensor of the supercharged pressure sensor is usually installed on the pipeline between the turbine supercharged exit and the electronic firing door inlet. , Its role is to measure the actual intake pressure pressure pressure. The engine control module adjusts the turbine speed according to the sensor signal, so that the actual superchargedness is in line with the target. /span>

It should be explained that in order to more accurately calculate the actual volume of the voltage, it also needs to install a supercharged air temperature sensor. This sensor has two design solutions, one is separate alone The design scheme of the component is as shown in the figure below.8561F170D933922 ~ TPLV-TT-Origin-Web: GIF.JPEG? URE = A2T9WXSVCMVJWPVGMEUQT85D85M%3d \”/>

The other is integrated with the pressure sensor sensor, as shown in the figure below. >

Basic technical parameters of supercharged pressure and supercharged temperature sensor are as follows: The supercharged pressure sensor uses a 5V working power supply, and the sensor signal voltage and actual pressure are linear change features; the pressure -blocking temperature sensor adopts a negative temperature coefficient thermistor, signal reference The voltage is 5

SPacing: 0.5px; \”> Pay attention to the actual maintenance work, if the supercharged pressure and pressure pressure temperature When the sensor is damaged, the line interruption, or the signal is severely deviated, the engine control module will set the fault code and enable the fault running mode at the same time.

<span style =\" background-color: #ff0000; –tt-darkmode-bgcolor: #ff0000; \"6. Water-cooled medium cold device

Because the air after the turbocharger pump pump is very hot, it needs to be cooled, otherwise the air density is small, the actual actual ones, the actual actual ones will Insufficient air intake quality affects the power performance of the engine. At the same time, the heat of the heat will also cause the engine to be too high, which can easily cause explosion. >

In order to install a cooling device between the exit of the turbocharger pump pump and the electronic festival import pipeline, that is, the medium -cooler. To achieve heat dissipation, this medium refrigerator is usually called an air -cooled mid -cooler, it is safeIn front of the vehicle, the pipeline connection path is long, as shown in the figure below.

Another kind of cooling fluid using an engine is used for heat dissipation, which is usually called a water-cooled medium refrigerator. In terms of layout, water -cooled mid -coolers usually have two layout forms. One is integrated with intake manifolds, high integration, but the volume of intake manifold assembly is large, as shown in the figure below.

At present, the new national six engines tend to use a water-cooled medium cold device. The fuel consumption of some working conditions is 2%to 10%, the power performance is 3%to 5%, and the power output of low -speed operating conditions increases by about 50%. Therefore, the technical advantages of water -cooled mid -cooler are more significant.