Diesel particulate filter - what is it? Installing, flushing and replacing the particulate filter

In Europe, diesel engines are consideredone of the most popular. But in diesel ICE, as in gasoline, fuel does not burn completely. As a result, various toxic and carcinogenic substances are formed in the exhaust gases. In addition, they also have soot, because hydrocarbons do not burn completely. In Europe in the 2000s, environmentalists developed a standard for the level of harmful emissions into the environment. Automakers, in order for their products to meet these standards, began to install a diesel particulate filter on a diesel engine. What is it and how it works, you need to know those who drive diesel engines. Today we will try to answer all these questions.

Main functions

In order to better understand the purpose of these devices, it is necessary to touch upon the topic of exhaust gases. The car exhaust contains a lot of highly toxic and carcinogenic substances.

So, carbon monoxide, unburned hydrocarbons,aldehydes, oxides of sulfur, tetraethyl lead have a very harmful effect on the environment. In addition, in the composition of the exhaust gases of a diesel car, in particular, heavy trucks, soot is contained in large quantities.

In order to reduce the concentration of this component, a diesel particulate filter was introduced into the design of a modern car. What is this detail? This is something like a catalyst in a gasoline engine.

What does the element look like

So, this device is designed toto neutralize soot - a product formed during the combustion of diesel fuel. There are two types - it is closed (DPF) and closed with the possibility of regeneration (FAP).

For all its simplicity, in fact, theseAuto parts for foreign cars have a rather complicated device. Regardless of the performance, the filter is a metal cylinder. On it are nozzles - input and output. The output is connected to the exhaust gas cleaning system.

The main element of the filter is a special matrix, which is made of silicon carbide.

It is enclosed in a cylinder made of metal. The structure of this matrix is ​​cellular. As for the section of cells, often this section is square. But cells with an octagonal shape are more efficient.

In addition, the diesel filter has several sensors in the design. This is a sensor that captures the pressure difference, and the sensor input and output temperature.

Principle of operation

The size of one soot particle is approximately 0.05 microns.The chemical composition of this product is nothing more than ordinary carbon. Retaining these particles using conventional means is very difficult due to the size of the element. To capture carbon black, it is necessary to use the principle of diffusion. To understand what a typical diesel particulate filter is, what kind of device it is, you need to look inside it.

So, the filter inside isceramic matrix. This is a whole series of tubes, with the ends closed at the same time. Inside this matrix, exhaust gases come from the motor side; however, when gases get into the tubes, they simply cannot move on. Then, through the walls of the tubes, they enter neighboring open cavities and then can exit from the matrix. In the process of diffusion, even the smallest particles remain inside the filter, which means that it performs its task.

Where is the particulate filter

Find this item is not difficult. The filter is often installed in the exhaust system of the car.

Due to the design features, detail can be foundbetween the muffler and the catalyst. In some cases, the device can be combined with a catalyst and is located directly behind the exhaust manifold. There, the maximum temperature of the gases, and such a filter has a catalytic coating.

Methods of operation

To effectively use the diesel particulate filter ondiesel, whose price is quite high (about 900 euros), it is necessary to properly operate the car. The thing is that in the process of cleaning the exhaust gases, the cells and tubes are clogged with soot. This leads to a decrease in the efficiency of the diesel engine.

Filter bandwidth decreases andresistance to an exit of exhaust gases increases. Many manufacturers, in order to increase the service life of this stock without the need for frequent replacement, have applied a special filter operation algorithm when the fill level is monitored. If the filter is filled so that engine power is lost, filter regeneration starts.

The reasons for the decrease in efficiency

There are several reasons why filtershammered. The main reason is the quality of diesel fuel. When filling the car with low-quality fuel, a large amount of soot is formed - the filter quickly clogs up, which reduces its service life.

Another reason is insufficient temperature. So, soot does not burn completely.

The thing is what constitutes a sootfilter on diesel. What is it? It not only detains particles, but also maintains the temperature for burning them. However, it should be said that this happens when the heating of the exhaust gases is high and is not less than 600 degrees Celsius. With lower rates of soot will not burn.

Among the causes of lowering the temperature of gases are alsoallocate a few. These are modes of movement, traffic jams, violation of the process of combustion of fuel. Thus, the temperature in the system will not rise if the speed of movement is low, and movement is accompanied by frequent stops.

Condition monitoring

In order to be able to controlthe state of the system, the exhaust path of the diesel engine is equipped with instrumentation equipment. It includes temperature and pressure sensors. These elements form the signals for the electronic control unit, and it determines whether the filter is full or not. When the item is heavily filled, the cleaning process begins.

How to clean

In order to restore efficiencyengine with a black particulate filter, it is enough to use a few simple methods that will help run self-cleaning. Regeneration can be both passive and active type.

In any case, the process occurs through the combustion of soot and the release of tubes and channels.

For the regeneration process can be usedincrease the level of heating of exhaust gases, additives, or washing the particulate filter. Additives will help reduce the temperature at which it will burn soot. And flushing with special substances will help clean the filter.

Passive Regeneration Method

This cleaning can be done directly.motorist. On the need for regeneration will report the corresponding indicator. Also, this process must be started if the dynamics or engine power is reduced.

Самое главное – обеспечить повышение температуры for exhaust gases. This is done by driving a car at full load. It is enough to drive 30-40 km so that the filter is completely clean and all the soot burned out. The second option is the use of special fuel additives.

Active regeneration

Этот режим может быть запущен автоматически ECU controller. For this, the electronics analyzes information from a temperature sensor and a pressure sensor. It informs the electronic control unit that the filter is clogged and the sensor reports the temperature. If it is not enough to soot completely burned, the ECU may additionally inject fuel in the process of exhaust gases. This will burn soot in the exhaust. It also allows you to raise the temperature to the desired level.

If there is other equipment in the exhaust line that also increases the heating of the exhaust gases, the ECU can also use them.

Washing

This procedure requires special fluids.

The procedure itself as a whole depends only on the type of agent.

So, the filter is removed and closed its holes.Then the cleaning fluid is poured inward in such a way as to fill the entire volume of the filter. Next, the product must be left alone for ten hours, while occasionally shaking the filter. After that, the item is washed with warm water and set back on the car. There are several types of liquids, and for each - its own method of washing. This should be remembered before performing these procedures.

Washing and cleaning will help to prolong the work of the element, because the replacement of the diesel particulate filter is a very expensive pleasure.

But sooner or later the time will come. It is recommended to change the filters after 180 thousand kilometers.

The wear of this design is primarily affected.driving conditions, fuel quality, and driving style. If the machine is experiencing significant loads, then this element may need to be replaced earlier.

So, we figured out what this part is for.in the car. The diesel particulate filter, like other auto parts for foreign cars, is an important part of modern cars. This element improves the ecological situation in the world, and this is people's health. High-quality ecology - a healthy society and happy children.