RU19558U1 - DEVICE FOR RECESSED GASES OF INTERNAL COMBUSTION ENGINE - Google Patents

Abstract

An exhaust gas recirculation device for an internal combustion engine having an intake, exhaust pipe, a recirculation valve, a bypass pipe connecting the exhaust and intake pipes, characterized in that the device further comprises a water tank, a water pump, an injector through which water is injected into the engine cylinder at the beginning of the exhaust stroke, moreover, a shut-off valve connected to the temperature sensor is installed in the high-pressure pipeline, and is located at the bypass pipeline at green recycle.

Description

2001106085

F 02 M 25/06

Exhaust Gas Recirculation Unit

The invention relates to engine building, in particular to exhaust gas recirculation devices.

Known exhaust gas recirculation systems with the supply of the latter for wet cleaning.

There is a method of reducing the content of nitrogen oxides in exhaust gases (description of the invention to USSR patent N 1839695 A3 MKI 5 F 02 M 25/06) and we have chosen as a prototype. This method is based on the passage of exhaust gases through wet cleaning. Gases are cooled and part of them goes to recirculation, in a constant volume, relative to the total gas volume of the diesel engine. Recirculation and humidification occur in all modes, namely: idling, small, medium and maximum loads. The device providing this method comprises a catalyst, a wet cleaning unit, an exhaust pipe, a bypass pipe, a recirculation valve, an air purifier, an inlet pipe.

The disadvantage of this device is that humidification occurs in all modes, including idling and light loads. In these modes, the temperature of the exhaust gases is very low (200-400 ° C) and their additional cooling in these modes using recirculation leads to unstable engine operation, increased deposition of resins in the exhaust tract and recirculation system, on the walls of the engine cylinders.

Exhaust gas recirculation at maximum loads leads to engine malfunctions, since the excess air coefficient in this mode is 1.2-1.4 and the engine is not able to receive recirculated gases without loss of power and increased fuel consumption . In addition, because of the water through which the exhaust gases pass, the resistance of the gases to the atmosphere increases, therefore, the coefficient of residual gases increases while the cleaning of the cylinder worsens, the erosion rate decreases, and fuel consumption increases.

The task, the solution of which the invention is directed, is to increase the efficiency of purification of exhaust gases.

This is achieved by the fact that: 1 - humidification will not be carried out at idle and low loads,

2-recirculation will not be carried out at maximum load;

3-humidification and cooling will occur without the passage of gases through the water. To do this, the device introduced:

2-recirculation unit not allowing to supply gases to the recirculation in maximum load mode;

3-nozzle for water injection into the engine cylinder;

The invention is illustrated by the diagram (figL) with the exhaust gas recirculation device depicted on it with water injection into the cylinder.

The device comprises an internal combustion engine cylinder 1; exhaust pipe 2; inlet pipe 3; bypass pipe 4; recirculation unit 5 with a drive from the high pressure fuel pump; water nozzle 6; a plunger type water pump 7 driven by the crankshaft of the engine and the high pressure fuel pump rail; low pressure pipe 8, high pressure pipe 9; water tank 10; drain pipe 11; electromagnetic shut-off valve 12; the temperature sensor of the working process 13 installed in the combustion chamber of the engine; filter 14.

The device operates as follows,

When the engine is idling and at low loads, the recirculation unit 5 provides a bypass of up to 80% of the exhaust gas from the total exhaust volume, since the coefficient and engine are capable of receiving a large amount of exhaust gas. In the same mode, the solenoid valve-shutter 12 is in the closed position and the water coming from the water pump 7 to the nozzle 6 through the high pressure pipe 9 is completely drained through the drain pipe 11 into the water tank 10. Thus, uncooled water is recirculated and not moistened gases, which favorably affects the starting properties of the engine.

When the engine switches to medium loads, the temperature of the working process rises, the temperature sensor 13 gives a signal to the solenoid valve-shutter 12, the valve 12 opens and water is injected through the nozzle 7 into the cylinder of the engine 1 at the beginning of the exhaust stroke. This causes heating and evaporation of water, since in this mode, the temperature of the exhaust gas is 500-700 ° C. The exhaust gases are cooled and moistened, in addition, chemical reactions of products of incomplete combustion with water in a vapor state at high temperature occur. Thus, cooled and humidified exhaust gases come to recirculation, this leads to a more significant decrease in the temperature of the cycle than when recirculation is not humidified and non-cooled exhaust gases, and consequently, to an increase in the degree of reduction of the formation of nitrogen oxides and soot. In addition, the water in the exhaust gas, mixed with air and entering the engine cylinder, evaporates and breaks up droplets of fuel. As a result of microexplosions, the ignition delay period increases and the fuel manages to evenly distribute throughout the combustion chamber. The number of zones with a lack of oxygen is reduced, which reduces the rate of formation of solid particles.

Homogenization of the charge also contributes to a decrease in the number of local zones with peak temperatures and, as a result, a decrease in the emission of nitrogen oxides.

The degree of recirculation is regulated by the recirculation unit 5 depending on the engine load.

With an increase in load, the recirculation unit 5 reduces the amount of gas entering the recirculation, by blocking the recirculation channel.

11when the engine is operating at maximum load (coefficient a 1.2 - 1.4), the recirculation unit 5 stops the bypass of the exhaust gases into the recirculation channel 4 so as not to disturb the normal course of the combustion process. The termination of the bypass ensures that the engine does not lose power and does not increase fuel consumption. However, due to the injection of water into the engine cylinder, the exhaust gases are humidified and cooled, and since the temperature of the exhaust gases in this mode is more than 800 ° C in the engine cylinder, water evaporates and reacts with carbon:

C + H2O + Q CO2 + H2

This leads to a significant reduction in particulate emissions.

The device can be manufactured as follows.

The design of the recirculation pipeline is a pipe welded at one end into the inlet pipe, and the other end into the box of the recirculation unit.

The design of the recirculation unit is a double-valve. One plate blocks the inlet to the recirculation pipeline, the other blocks the exhaust gas outlet to the atmosphere. Both plates are rigidly connected by a thrust located on the rotating axis. By turning the axis, the amount of gases supplied to the recirculation is regulated. The water tank is an arbitrary shape water tank.

Pipelines of high and low pressure, drain pipe - these are rubber-fabric hoses of various sections.

The water filter is similar to the fine fuel filter.

The plunger type water pump is similar in design to the high pressure fuel pump.

The nozzle is full-time, single-hole, pinless.

The solenoid-shutoff valve is a three-channel (discharge, pressure., Drain) valve with an electromagnet. The locking element is a ball. In the closed position there is a constant drain.

The exhaust gas recirculation device with water injection into the cylinder allows the transfer of uncooled and non-moistened gases at idle and low loads, and water is injected into the engine cylinder at the beginning of the exhaust stroke at all modes, as well as stopping exhaust gas recirculation at maximum loads. Thus, at idle and low loads, there will be no humidification and cooling of the exhaust gases, which will favorably affect the operation of the engine, and at the maximum mode there will be no exhaust gas recirculation, which will not entail a reduction in power and an increase in fuel consumption.

In addition, at maximum mode, due to the injection of water and its evaporation, chemical reactions of combustion products with water will take place, which helps to reduce the amount of soot.

Exhaust gas recirculation at idle, low and medium loads reduces nitrogen oxide emissions.

It is assumed that the use of an exhaust gas recirculation device with water injection into the cylinder will reduce emissions of nitrogen oxides by 70% and soot by 80%.

Authors of the invention: (- -Anisimov I.A.

 Zhernakov A.A. Stein G.V.

Claims (1)

An exhaust gas recirculation device for an internal combustion engine having an intake, exhaust pipe, a recirculation valve, a bypass pipe connecting the exhaust and intake pipes, characterized in that the device further comprises a water tank, a water pump, an injector through which water is injected into the engine cylinder at the beginning of the exhaust stroke, moreover, a shut-off valve connected to a temperature sensor is installed in the high-pressure pipeline, and is located at the bypass pipeline at green recycle.