Turbocharger device: description, principle of operation, main elements

2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16

Before proceeding to the consideration of the turbocharger device itself, you should know that the power of an internal combustion engine depends entirely on how much air and fuel enters it. Therefore, if you increase these indicators, you will also increase the power of the internal combustion engine.

Turbine Description

The turbocharger device and its appearance is the result of a constant race of people to increase engine power. It is important to add here that such a turbine has become an effective solution not only for gasoline engines, but also for diesel models. Most often, such devices are installed on those engines that have a small amount of air supplied. Here it is important to understand the following: the larger the engine itself, the more air and fuel it consumes and the more power it has. In order to achieve the same power from a smaller engine, you need to increase the amount of air that fits in the cylinders.

Turbocharger is a device that is designed toto force a large amount of air into the engine using the exhaust gases. A turbocharger has two main elements - a turbine and a centrifugal pump. Between themselves, these two parts are connected by a rigid axis. The elements rotate at speeds up to 100,000 revolutions per minute, and they also drive the compressor.

Turbine parts

The turbocharger device includes 8 parts. There is a turbine wheel that rotates in a housing with a special shape. The main purpose is to transfer the energy of the exhaust gases to the compressor. The starting material for the assembly of these elements are heat-resistant materials, such as ceramics.

The turbocharger device also includes a compressor wheel that sucks in air. It also deals with its compression and injection into the engine cylinders. The wheel is located in a special housing, like a turbine. Both of these wheels are mounted on the rotor shaft, the rotation of which is carried out on plain bearings.

The design and operation of a turbocharger, especially in gasoline engines, requires additional cooling. Usually this is a liquid cooling system. In addition to cooling the system itself, the compressed air is also cooled. For this, the turbine has an air or liquid type intercooler. Cooling the air is essential as it increases its density and hence the pressure.

This system is controlled by a pressure regulator. This bypass valve is capable ofrestrict the flow of exhaust gases. In this way, some will pass by the turbine wheel.

The essence of the work

The device of the turbocharger and the principle of its operation is based on the use of exhaust gases. The energy of these gases will drive the turbine wheel. To transfer this energy, the turbine wheel is attached to the rotor shaft, rotating it. In this way, energy is transferred to the compressor wheel. This element is engaged in forcing air into the system, as well as compressing it. The compressed air passes through the intercooler, which cools it down. After that, the substance enters directly into the engine cylinders.

More information

The turbocharger device and the principle of operation are in some way independent, on the one hand, from the internal combustion engine, since there is no rigid connection with the engine shaft. On the other hand, the speed of rotation still in some way affects the efficiency of the turbine. It is connected in the following way. The more revolutions the engine makes, the more powerful the flow of exhaust gases will be. Because of this, the speed of rotation of the turbine shaft will increase, which means that the amount of air that will enter the cylinders will increase.

The design and operation of the turbocharger have several negative sides. One of the drawbacks is called "turbo lag". With a sharp press on the gas pedal, the rapid increase in power will be somewhat delayed. After passing through the "turbojam" there is a sharp jump in pressure,which is called the "turbo lift".

Fixing deficiencies

The appearance of the first drawback is due to the fact that the system is inertial. Because of this phenomenon, there is a discrepancy between the performance of the turbine and the power that is required from the engine. There are three ways to solve this problem. Since the device of a diesel turbocharger is similar to a gasoline one, they are also suitable for it. Here's what you can do:

1. Use variable geometry turbine.
2. Use two parallel or two compressors in series.
3. Use the combined boost system.

As for the variable geometry turbine, it is quite capable of solving the problem by changing the area of the inlet valve. Such a system is very often used in diesel engines.

Description of different systems

Purpose, the device of the turbocharger is the same as that of a conventional turbine. The main difference is that the instrument has only 5 main parts, not 8.

A system of turbines connected in parallel is used. Such a system is best suited for sufficiently powerful V-engines. In this case, one small turbocharger is installed for each row of cylinders. The advantage is that the inertia of several small devices is less than that of one large turbine.

The device and principle of operation of the compressor does not differ depending onfrom its volume, however, this plays an important role, for example, when using a serial connection of two turbines. In this case, each device will be activated at a certain speed.

A boost system is also used, which uses both a mechanical and a turbocharger. If the engine speed is low, then a mechanical device for pumping air is included in the work. If a certain threshold is exceeded, the mechanical device will turn off, and the turbocharger will start working.

What are the benefits of a turbine

The following benefits stand out when using a compressor:

1. The widespread use of this device has become possible due to the simplicity and reliability of its design. In addition, the introduction of this device into the internal combustion engine system increases engine power by about 20-35%.
2. The compressor itself cannot cause a breakdown, since its performance directly depends on other systems, for example, gas distribution.
3. It is possible to save from 5 to 20% of fuel. If you install a turbine in a small engine, the fuel combustion process will become more efficient, which means that efficiency will increase.
4. A good advantage of such engines is observed on roads passing, for example, in the mountains. This is especially noticeable when compared with atmospheric counterparts.
5. The design and principle of operation of the turbocharger allow it to function as an additional silencer in the exhaust system.

Application Features

Despite the fact that the compressor itself practically does not fail, situations occasionally arise when its operation stops.

Today, the most common cause of turbocharger shutdown is that the central cartridge of the turbine is clogged with oil. Most often, such a problem occurs due to the fact that after prolonged and serious loads on the turbocharging, its work stops abruptly. In order to get rid of this trouble, it is necessary to install a water cooling system. The lines of this system will create a heat absorption effect, which will reduce the temperature in the central cartridge. It is worth noting that this effect will occur for some time after the engine is completely stopped, as well as after the complete cessation of coolant circulation.

Varieties of turbines

As for the types of turbocharger, there are sleeve type and ball bearing type.

If we talk about bush type turbochargers, they have been used for quite a long time. However, they had a number of shortcomings, which was associated with their design features. This did not allow using the potential of such a system by 100%. Ball-bearing units are newer, which have taken into account the shortcomings, and therefore they are gradually replacing bush compressors.

When comparing these two types of turbines, the ball bearing is considered more economical, as it consumes significantlyless oil than sleeve type. Also, compressors have an indicator that is responsible for the response of the turbine to pressing the gas pedal. For ball bearing types of turbines, this indicator is better, which allows for an improvement in response by about 15% compared to sleeve ones.

Instrument malfunctions

Here it should be said that the turbocharger is the only attachment of the engine, which is closely connected during operation with almost all other vehicle systems. Based on this, it becomes quite obvious that minimal deviations in the operation of any system will lead to the fact that compressor wear will increase significantly. To date, there are several reasons that most often become an obstacle in the operation of the turbine:

• It is possible for foreign objects to get into the mechanism. Due to the huge speed of rotation of the motor, this may well lead to damage, for example, to the impellers.
• Lack of lubricants. The higher the dynamic loads, the higher the chance that the destruction of the oil "film" will occur. This, in turn, will lead to "dry" friction, which affects the system in the most negative way. The cause of this malfunction can be any reason due to which the oil does not reach fully. For example, clogged oil cylinders, filters, oil pump wear, etc.