RU2440509C2 - Method of cold start-up and warm-up of piston internal combustion engine and system for its implementation - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: method involves hydrogen obtaining in electrolysis unit aboard the transport vehicle and the system that supplies hydrogen to the engine. At that, hydrogen is supplied in the required amount and as per the specified algorithm, depending on the cooling liquid temperature. Cold start-up and warm-up system includes electrolysis unit, pipelines, sensors, electric valves and control unit. Hydrogen and oxygen is obtained separately in the electrolysis unit. Hydrogen is supplied through receiver, electric valve and jet nozzle to ICE inlet pipeline. Oxygen is removed to the atmosphere. Supply of gaseous hydrogen to ICE inlet pipe at cold start-up and warm-up of the engine contributes to stable combustion of fuel-air mixture with higher degree of completeness at low concentration of toxic substances in waste gases.

EFFECT: reducing toxicity level of waste gases at cold start-up and warm-up of internal combustion engine with electronic control system and catalytic neutraliser.

2 cl, 3 dwg

Description

The invention relates to the field of mechanical engineering, in particular to engine building, and in particular to methods and devices for cold starting and heating piston internal combustion engines (ICE) with spark ignition, equipped with an electronic engine control system (ECM) and a catalytic converter.

Known methods and devices for starting an internal combustion engine by heating the air at the inlet, heating the coolant and / or the engine as a whole and others, making it easier to start a cold engine [1, p. 321, 332 ... 334].

The disadvantage of these methods is that their implementation requires an energy-intensive heating element and a long time for heating media and / or warming up the engine. In addition, during start-up and warm-up, there is a significant release of toxic substances with exhaust gases into the environment.

There is a method of cold start of internal combustion engines of a piston type, according to which the crankshaft is scrolled and due to only adjustment, the engine warms up quickly, without using additional devices and without the cost of additional energy [2].

However, this method does not provide a reduction in emissions of harmful substances with exhaust gases during start-up and warm-up of the engine

The closest in technical essence and the achieved result to the claimed is a method of improving the process of fuel combustion in an internal combustion engine and a system for its implementation [3]. The essence of the invention lies in the fact that on board a vehicle in the cell receive hydrogen. At idle, hydrogen enters the inlet pipe with the ratio of the mass of hydrogen to the mass flow rate of the main fuel in the range of 0.01-0.04, and the air-fuel mixture is depleted to the coefficient of excess air α = 1.2 ... 1.4. Oxygen from the electrolyzer is piped to the exhaust system. When the engine is running, the depleted air-fuel mixture with an admixture of hydrogen gas burns steadily and with high completeness with a minimum concentration of toxic substances in the exhaust gases.

The disadvantage of this invention is a significant emission of harmful substances with exhaust gases during the start-up and warm-up period of the engine, since the catalytic converter is inefficient due to its low temperature. As tests of the car engine for compliance with modern toxicity standards show, the main amount of harmful substances emitted (up to 50%) falls on the engine start-up and warm-up modes.

The problem solved by the invention is the technical result - the reduction of toxicity of exhaust gases during cold start and warm-up of a reciprocating internal combustion engine equipped with an electronic engine control system and a catalytic converter.

The technical result is achieved by the method of cold starting and warming up a reciprocating internal combustion engine, including producing hydrogen in the electrolyzer on board the vehicle and supplying a fuel-air mixture and hydrogen to the combustion chamber, and at the time of starting the engine at an initial coolant temperature of from -30 ° C to + 50 ° C, hydrogen is supplied from the receiver to the fuel-air mixture, and at the time of starting the engine, the electronic control unit sets the coefficient of excess air by 0.05 ÷ 0.10 more atomic value, and as the engine warms up to a coolant temperature of + 50 ° С, the excess air coefficient is reduced to the standard values corresponding to the operation of the engine on main fuel, and the electrolyzer is connected to the vehicle’s on-board power supply and hydrogen is accumulated in the receiver only after reaching the cooling temperature liquid + 50 ° C and the engine speed more than 1500 min ^-1, which is formed in an electrolytic cell wherein oxygen is removed in the environment, the cell is disconnected from the onboard elec Roset vehicle when a predetermined hydrogen pressure in the receiver and / or engine speed less than 1500 min ^-1.

The technical result is achieved by a cold start and warm-up system for a reciprocating internal combustion engine comprising a voltage converter, a relay, an electrolyzer, an oxygen pipe with an electric valve, a receiver equipped with a pressure sensor, a hydrogen pipe with an electric valve and a jet, a crankshaft position sensor, a coolant temperature sensor and an electronic system unit control, and the hydrogen tank of the electrolyzer communicates via a hydrogen pipe with the engine inlet pipe through the receiver, the electro-valve an and a nozzle, and the oxygen tank of the electrolyzer communicates via an oxygen pipe with the environment through an electrovalve.

Figure 1 shows a diagram of a system for implementing the proposed method for cold starting and warming up a piston internal combustion engine.

The system contains an electrolyzer - 1; receiver - 2; ICE - 3; electronic control system unit (BU) - 4; oxygen pipeline electrovalve - 5; voltage converter - 6; relay - 7; pressure sensor - 8; hydrogen pipeline electrovalve - 9; jet - 10; the crankshaft position sensor (DPKV) - 11 and the coolant temperature sensor (DTOZH) - 12.

The cell 1 through the relay 7 and the voltage Converter 6 is connected to the vehicle electrical system. The oxygen tank of the electrolyzer 1 through the oxygen pipe communicates with the atmosphere through the electrovalve 5. The hydrogen tank of the electrolyzer 1 through the hydrogen pipe communicates with the receiver 2, and through the electrovalve 9 and the nozzle 10 with the intake pipe of the ICE. Receiver 2 is designed for the accumulation and storage of hydrogen. The receiver 2 is equipped with a pressure sensor 8. The electrovalves 5, 9, the relay 7, the pressure sensor 8, the sensors 11 and 12 are connected via wires to the electronic control unit 4. The signals from the sensors 8, 11 and 12 are fed to the electronic control unit 4, which sends control commands to the electrovalves 5, 9 and relay 7.

The system is as follows.

At the time of starting the engine, when the crankshaft rotational speed reaches 50 ... 150 min ^-1 , recorded by DIKV 11, and the coolant temperature is below + 50 ° С, recorded by DTOZh 12, BU 4 will command the valve 9 to open, and the hydrogen located in receiver 2, is introduced into the fuel-air mixture through the nozzle 10. The electronic engine management system reduces the supply of primary fuel and sets the coefficient of excess air by 0.05 ÷ 0.10 more than the nominal value. As the engine warms up and, consequently, the temperature of the coolant rises, the hydrogen supply to the inlet pipe decreases and stops when the temperature of the coolant reaches + 50 ° C by issuing a command from the control unit 4 to the solenoid valve 9, and the coefficient of excess air is reduced to standard values corresponding to engine operation on the main fuel.

Further operation of the internal combustion engine occurs in accordance with the standard values of the coefficient of excess air.

When the engine shaft speed exceeds 1500 min ^-1, the electronic control unit 4 sends a command to the electrolyzer 1 to the relay 7. During the operation of the electrolyzer 1, hydrogen accumulates in the receiver 2, which is used in the next engine start if the coolant temperature is less than + 50 ° C. Upon reaching the set hydrogen pressure in the receiver 2, which is detected by the pressure sensor 8, the control unit 4 will send a command to the relay 7 to turn off the electrolyzer 1.

During operation of the electrolyzer 1, oxygen is accumulated in the oxygen tank. Excess oxygen is discharged into the environment by the commands of the control unit of the cold start system and warming up the engine 4 to the electrovalve 5.

During the operational operation of the engine in the case of a decrease in the engine speed of the internal combustion engine less than 1,500 min ^-1, the electronic control unit 4 switches off the power of the electrolyzer 1 via relay 7, thereby increasing the efficiency of the joint operation of the engine and the electrolyzer.

The supply of gaseous hydrogen to the ICE intake pipe during cold start and engine warming contributes to the stable combustion of the fuel-air mixture with a higher completeness at a low concentration of toxic substances in the exhaust gases and to reduce fuel consumption.

An example of a specific implementation.

The proposed system for implementing the method of cold starting and warming up the piston ICE was mounted on a VAZ-21102 car. Figure 2 is a diagram of the layout of the system on the car, and figure 3 is the test results of the proposed method and system on the car.

The tests of the car in stationary conditions were carried out by conducting a gas analysis of exhaust gases during the start-up and warm-up period of the engine, i.e. the concentration of products of incomplete combustion, namely, hydrocarbons (CH) and carbon monoxide (CO), was determined depending on the time of engine warming up without hydrogen supply and with hydrogen supply. It was experimentally obtained (Fig. 3) that in the first 50-60 seconds of engine warm-up, the concentration of CH decreases by 4-2.5 times, the concentration of CO - by 8-5 times. At the end of engine warm-up (100-120 s) and the cessation of hydrogen supply, the concentrations of CH and CO approach the values characteristic of engine operation without hydrogen supply.

Tests of the VAZ-21102 vehicle in the 4C (E-2) configuration according to the EURO-3 driving cycle according to the methodology of UNECE Regulations 83-05 showed that the application of the proposed method and system can reduce mass emissions for the CH driving cycle by 30%, CO by 40 % The total emissions during the driving cycle were SN - 0.20-0.26 g / km, СО - 1.4-1.6 g / km. Mass emissions of NO _x during the driving cycle have not changed.

Information sources

1. Internal combustion engines: piston and combined engine systems. Textbook / Under the general. ed. A.S. Orlina, M.G. Kruglova. - M.: Mechanical Engineering, 1985 .-- 456 p.

2. Patent No. 2290530 RU. The cold start method of a piston type internal combustion engine / Borisov A.O., Baiburin R.V. Published on 2006.12.27.

3. Patent No. 2167317 RU. A method for improving the process of fuel combustion in an internal combustion engine and a system for its implementation / Rusakov MM and others. Published on May 20, 2001.

Claims (2)

1. A method for cold starting and warming up a reciprocating internal combustion engine, comprising producing hydrogen in an electrolyzer on board a vehicle and supplying a fuel-air mixture and hydrogen to the combustion chamber, characterized in that at the time of starting the engine at an initial coolant temperature of from -30 to + 50 ° C, hydrogen is supplied from the receiver to the fuel-air mixture, and at the time of engine start-up, the engine electronic control unit sets the coefficient of excess air by 0.05 ÷ 0.10 more than the standard value and, as the engine warms up to a coolant temperature of + 50 ° С, the excess air coefficient is reduced to the standard values corresponding to the operation of the engine on the main fuel, and the electrolyzer is connected to the vehicle’s electrical network and hydrogen is accumulated in the receiver only after reaching the coolant temperature + 50 ° С and engine shaft rotation frequency of more than 1500 min ^-1 , the oxygen generated in the electrolyzer is removed to the environment, the electrolyzer is disconnected from the on-board power supply abundance upon reaching a predetermined hydrogen pressure in the receiver and / or engine shaft speed of less than 1500 min ^-1 . 2. A cold start and warm-up system for a reciprocating internal combustion engine comprising a voltage converter, a relay, an electrolyzer, an oxygen pipe with an electric valve, a receiver equipped with a pressure sensor, a hydrogen pipe with an electric valve and a jet, a crankshaft position sensor, a coolant temperature sensor and an electronic control unit the engine, characterized in that the hydrogen tank of the electrolyzer communicates via a hydrogen pipe with the engine inlet pipe through the receiver, solenoid valve and nozzle er, and the oxygen tank of the electrolyzer communicates via an oxygen pipe with the environment through an electrovalve.

Images