XIII Международная студенческая научная конференция Студенческий научный форум - 2021

In most developing countries, there is an annual increase in the number of vehicles. According to the Verhulst equation and its S-shaped curve, a period of stagnation will eventually come, but at the moment our country is on the verge of a sharp increase in vehicles.

In this regard, there is an increase in the volume of greenhouse gases in the atmosphere of the planet, which negatively affects the flora, fauna and human health. this factor contributes to the creation of various standards, prohibitions and requirements for internal combustion engines.

The main requirement for modern reciprocating internal combustion engines (ICE), in addition to reducing fuel consumption, is to reduce toxic components in the exhaust gases.

One of the solutions to this problem is the afterburning of these components by supplying air to the exhaust system (EGR valve). Currently, various types of neutralizers are used in the internal combustion engine, which help to reduce the toxicity of exhaust gases, including through additional air supply, however, in this case, the components do not burn out completely, since the main share of air is nitrogen, which does not participate in oxidation and goes out into the environment in its original form.

Under the influence of increasing the level of technological development, the creation of new materials and the annual reduction of their cost, the development of such a technology as the cell membrane.

Recently, a partially permeable membrane has been widely used. The task of such membranes is the separation of two liquid or gaseous phases, which occurs under the action of a driving force.

With the help of such a cell membrane, you can separate oxygen from the air and direct it to burn out toxic components. At the same time, by adding some of it to the intake of the internal combustion engine, you can intensify the process of burning.

The addition of oxygen to the exhaust gases of the engine leads to the most complete oxidation of the combustion products. Carbon monoxide is oxidized to carbon dioxide, and nitrogen to no2 (nitrogen dioxide), no3, and in small amounts to n2o5 (nitrogen pentoxide).

From the proposed membrane, you can create a device or filter, but you should proceed from the geometric dimensions of the membrane, its properties and cost.

Such a filter works on the principle of dividing air into its constituent elements. A hollow fiber membrane is a cylindrical cartridge containing a porous polymer fiber. Due to the "absorbing" features and various partial pressures on the membrane surfaces, the air passing through the filter is divided into its constituent components – nitrogen and oxygen. The gas separation layer of the fiber has a thickness not exceeding one tenth of a micrometer. Such dimensions provide a high specific permeability of gases through the polymer fiber.

However, it should be taken into account that in order to ensure the required pressure level, an additional device (compressor) must be introduced, and also take into account the additional energy spent on its operation.

In addition, at the same time, a small part of the resulting oxygen can be directed to the engine intake. An increase in the O2 concentration in the combustion chamber leads to a more complete oxidation of the fuel and an intensification the process of burning.

Preliminary calculations have shown that with an increase in the proportion of oxygen in the air to a certain value, there is a slight decrease in fuel consumption. In addition, it was identified a slight increase in the coefficient of performance (COP). Here it is worth to note that the strong increase in the proportion of oxygen in the intake the engine will increase fuel consumption and reduce engine efficiency (due to the increase of the inlet temperature of the internal combustion engine, reducing the air density and, consequently, reducing the filling ratio).

Thus, an increase in the concentration of oxygen in the exhaust gases can reduce the release of toxic components into the environment, and based on the preliminary calculation, we see that an additional mass of oxygen at the inlet can improve its economic performance. Additional cooling of the intake air, in our opinion, can further increase these indicators.

References:

1. Stukanov, V. A. Device of cars: textbook manual / V. A. Stukanov [et al.]- Moscow: INFRA-M, 2013. – 496p.

2. Alekseev I. V., Morozov K. A., Shatrov M., G. Automobile engines. A textbook for students of higher educational institutions. Ed. Academy., 2011, lan http://e.lanbook.com/

3. Membrane technology of gas separation // second industrialization of Russia URL: https://clck.ru/SKrDi