RU2265739C1 - Method of operation of internal combustion engine and internal combustion engine implementation the method - Google Patents

Abstract

FIELD: mechanical engineering; internal combustion engines.

SUBSTANCE: according to proposed method of operation of internal combustion engine, by intake of compressed air, its compression, injection and combustion of fuel and exhaust of waste gases and delivery of additional working medium at transient conditions, compression ratio of air at transient conditions is increased by turning rotor of turbocompressor, and at transient starting and keeping of engine at hot stand-by mode, engine is warmed before delivery of fuel and compressed air into cylinders. Rotor of turbocompressor is turned at transient conditions by steam formed by heat of exhaust gases in heat exchanger installed at engine outlet and by additional working medium received by combustion of mixture of air from air space and exhaust gases of engine at engine outlet before heat exchanger. Crankshaft of engine at transient conditions and operation at overload is turned up by electric machine supplied by storage battery through frequency and voltage converter. Used as additional working medium supplied to intake of engine, compressed air from reservoir is used with replenishment of air by electric compressor. Additional working medium-heat carrier is introduced into exhaust gases of engine at transient conditions and at operation at low load. Said heat carrier is prepared by combustion of mixture of fuel delivered under pressure from reservoir at engine outlet before heat exchanger, and mixture of air from air space and exhaust gases of engine. Storage batteries are trickle-charged by thermoelectric generator built into heat exchanger, and their charging is carried out when engine operates at low loads by electric machine through frequency and voltage converter. Delivery of energy from frequency and voltage converter to all consumers and delivery of steam from heat exchanger are provided under all operating conditions.

EFFECT: improved efficiency of engine operation under static and transient conditions, power and heat supply of consumers, dynamic characteristics of turbocompressor.

3 cl, 1 dwg

Description

The invention relates to the field of engine building and can be used to improve the efficiency of internal combustion engines in static and transient combustion modes.

A known method of operation of an internal combustion engine, which provides for supplying additional oxygen (an oxidizing agent) and an additional working fluid obtained by burning fuel to the engine cylinders during transient operation, as well as twisting the rotor of a turbocompressor with a reversible electric machine. Moreover, in prestarting modes, due to the combustion of fuel in an electric torch device, the engine is preheated while the starter batteries are recharged from a reversible electric machine driven by a turbocharger (see RU 2231660, published June 27, 2004).

The disadvantages of this method of operation and internal combustion engine:

1. Insufficiently effective preheating of the engine, as well as recharging the starter battery, caused by the fact that the turbocharger turbine in this case operates in off-design mode with a low speed and low efficiency. In this mode, it is not possible to remove large power from it simultaneously to the compressor drive and recharging the starter battery.

2. The limited supply and explosive use of an additional oxidizing agent, which is used as oxygen compressed in a high-pressure tank.

3. Adverse physicochemical and thermodynamic characteristics of the additional working fluid supplied to the engine cylinders during load surges. As an additional working fluid, high-temperature products of fuel combustion and air-oxygen mixtures are used. The low density of the high-temperature gas mixture does not allow to place a sufficient amount of working fluid in the engine cylinders. The imperfection of the processes of mixture formation and combustion in an electric torch device can lead to local re-enrichment of the working mixture with oxygen or products of incomplete combustion of fuel (soot), which entails the risk of deposits and subsequent explosions in the intake manifold, disruptions to the engine’s working process, contamination of cylinder piston parts and gas-air ducts .

4. Low engine efficiency at low loads and overloads.

5. Limited capacity turbocharger power supply consumers.

6. Low efficiency due to the lack of heat recovery of exhaust gases.

The objective of the invention is to increase the efficiency of the internal combustion engine in static and transient modes of operation (starting, accelerating, load shedding, working at low loads, working with overload), expanding the possibilities of power supply and heat supply to consumers during engine operation, improving the dynamic characteristics of a turbocharger .

The problem is solved in the method of operation of the internal combustion engine by inlet of compressed air, its compression, injection and combustion of fuel, exhaust gas, supply in transition modes of an additional working fluid by a control signal generated at the time of reaching maximum fuel supply in a given mode, while the degree of air compression in transient conditions is increased by tightening the rotor of the turbocompressor, and in transient modes of starting and maintaining the engine in the “hot reserve” before fuel supply and compressed air into the cylinders, the engine is heated, according to the invention, the rotor of the turbocompressor is twisted in transient conditions by steam generated due to the heat of the exhaust gases in the heat exchanger installed on the engine outlet and an additional working fluid obtained by burning air mixture from the air tank at the engine outlet before the heat exchanger and engine exhaust gases, the crankshaft of the engine in transient conditions and operation with overload is tightened up by an electric machine powered by batteries a battery through a frequency and voltage converter, using compressed air from a tank with its supply as an additional working fluid supplied to the engine inlet, which is replenished by an electric compressor, and introduced into the exhaust gases of the engine during transient conditions and when operating at low loads additional working fluid - heat carrier, prepared by burning at the engine outlet in front of the heat exchanger a mixture of fuel supplied under pressure from a tank with its reserve, and a mixture of air from air capacity, as well as engine exhaust gases, the batteries are charged from a thermoelectric generator built into the heat exchanger, and they are charged when the engine is running at light loads from an electric machine through a frequency and voltage converter, while at all operating modes, electricity is supplied to consumers from a frequency and voltage converter, as well as steam from a heat exchanger.

To implement this method, an internal combustion engine is proposed, comprising at least one cylinder with a piston kinematically connected to the shaft, a turbocompressor in which the turbine outlet and compressor inlet are connected to the atmosphere, an inlet pipe, an exhaust pipe, a hydrocarbon supply line fuel to the cylinders, equipped with a high pressure fuel pump equipped with a maximum fuel supply sensor, a high pressure tank connected to the gas supply solenoid valve oxidizing agent into the engine, the battery, the control device, the control outputs of which are connected to the limit position sensor of the injection pump rail and the temperature sensor, and the control inputs with the electro-valve for supplying the gaseous oxidizer to the engine inlet, the electro-valve for supplying fuel, as well as the frequency and voltage converter, the electric torch device equipped with an electro-ignition device for igniting the air-fuel mixture, a tank with a fuel supply, a fuel solenoid valve connected to an electric faculty According to the invention, the engine further comprises an air compressor equipped with a direct current drive electric motor, an electrovalve for supplying a gaseous oxidizer (air) to an electro-torch device, an electrovalve for supplying steam into the turbine of the turbocharger, shell-and-tube heat exchanger with a supply of water in the annulus and built-in thermo an electric generator, an electric load (active current) sensor installed in the frequency and voltage converter, an air pressure sensor installed in the high pressure vessel, the electric machine being kinematically connected to the engine crankshaft, the output of the high pressure vessel is simultaneously connected to the air electric compressor, the upper part of the vessel with fuel supply, through the air supply valve to the electric torch device with the first gas inlet of the electric torch device, through the oxide supply valve an engine inlet with its inlet pipe also connected to the compressor outlet, the second gas inlet of the electric torch device is connected to the exhaust pipe (collector) of the engine, and the outlet through the pipe space of the heat exchanger is connected to the turbine inlet, which is also connected to the steam supply solenoid valve the upper part of the annulus of the heat exchanger, and the thermoelectric generator built into the heat exchanger is connected to the battery, and additional control inputs are arranged CTBA control connected to the pressure sensor and the sensor electrical load, and the additional control outputs connected electric compressor with a motor, a solenoid and a solenoid valve supplying steam into the air supply electric-device.

This engine design provides: improving the quality of transient engine operation, accompanied by a violation of the combustion process and the injection pump rail at the maximum feed (start, acceleration, surge, load) due to the fact that the quantity (density) of the working fluid increases, the acceleration time decreases to the nominal frequency of rotation of the turbocompressor due to the supply of an additional working fluid to the turbine, as well as the supply of additional power to the engine shaft from an electric machine receiving power from cumulative battery through a frequency and voltage converter; increasing the efficiency of engine preheating and maintaining it in a “hot reserve” due to more stable and productive operation of the electric torch device, as well as the use of a thermal generator to recharge the battery; increasing the efficiency of the engine with overload due to the possibility of supplying additional power to the motor shaft from an electric machine; increasing the efficiency of the engine due to the equalization of the load schedule and reducing the time of working with a small load due to the use of the battery together with the frequency and voltage converter as an electric energy storage device; improving the efficiency of engine use and its overall efficiency due to the utilization of the heat of the exhaust gases in the heat exchanger, accompanied by the generation of steam and additional electricity; reduction of explosion and fire hazard of engine operation due to the use of compressed air instead of oxygen as an additional working fluid.

Thus, the claimed technical device allows to implement the inventive method.

It follows from the foregoing that when implementing the proposed method and device for its implementation, a technical result is achieved, which consists in improving the quality of transient engine operation modes (starting, acceleration, load shedding), increasing the overload capacity of the engine, improving technical and economic indicators when the engine is running on partial loads, utilization of the heat of the exhaust gases of the engine, accompanied by additional generation of thermal and electric energy, the possibility of power supply and those supplying consumers with the engine operating at all possible operating modes: “hot standby”, working in a transport mode with a variable speed, working in a motor-generator mode with a constant speed, improving the dynamic characteristics of a turbocharger.

The claimed group of inventions meets the requirement of the unity of the invention, since the application relates to objects of the invention of the same type, of the same direction, providing the same technical result in essentially the same way.

In the drawing, explaining the invention, shows a schematic diagram of an internal combustion engine that implements this method of operation. The scheme includes an engine 1 with systems and mechanisms for the fuel combustion process, a block pump plunger pump TNVD 2 mounted on the skeleton of engine 1 and equipped with a rail 3, a limit switch sensor of the injection pump rail (microswitch) 4, a tank 5 with an oxidizer (air) reserve , compressor 6 and turbocharger turbine 7, shell-and-tube heat exchanger 8 with a built-in thermoelectric generator installed at the engine outlet, electric torch device 9, tank with fuel supply 10, electric machine 11, aircomp essor 12 with electric drive 13, control device 14, electric power storage (battery) 15, frequency and voltage converter 16, temperature sensor 17, electric load (active current) sensor 18, air supply valve 19 to the engine inlet, air valve 20 to the air electric torch device, electric valve 21 for supplying fuel to the electric torch device, electric valve 22 for supplying steam to the turbine of the turbocompressor, electrosapal device 23, air pressure sensor 24.

The internal combustion engine operates as follows: on a command to start the engine, the control device 14 gives a signal to open the valves 20 and 21, as well as to pulse-switch on the electric fuel injection device 23. In this case, the air-fuel mixture ignites and burns in the electric torch device 9. High-temperature exhaust gases ) from the electric torch device 9 enter the heat exchanger 8 and then through the turbine 7 into the atmosphere. In this case, part of the thermal energy from the exhaust gas is transmitted through the heat exchanger 8 to the engine cooling system for its prestarting heating. Prestarting of the engine can be done by supplying hot water or steam to the engine from the heat exchanger body 8. At the same time, if necessary, the battery 15 is recharged from the thermoelectric generator built into the heat exchanger 8, which directly converts thermal energy into electrical energy. After warming up the engine 1 and reaching the temperature required for reliable starting and switching on the load according to the signal from the temperature sensor 17, the control device generates a signal to start the engine 1 by turning on its electric starter or electric machine 11 in the motor mode from the battery. Simultaneously with scrolling the engine crankshaft by a signal from the control device 14 by opening the electrovalve 19, air is supplied under pressure to the engine cylinders, and the fuel and air supply to the electro-torch device is stopped by closing the electrovalves 20 and 21. The supply of compressed air to the engine inlet increases the degree increasing compression pressure in the cylinders and more reliable ignition of the fuel.

If it is required to maintain the engine in constant readiness for starting and receiving a load for a long time (“hot reserve” mode), then after the above-described period of warming up the engine to a predetermined temperature (if there is no command to start and turn on the load) by a signal from the sensor 17, the control device 14 generates signals to close the solenoid valves 20 and 21. In the process of further cooling of the engine when it reaches the minimum acceptable temperature by the signal from the sensor 17, the valves 20 and 21 open, turn on lektrozapalnogo devices and high-temperature heating of engine exhaust gases. In this case, the battery 15 is constantly recharged from the thermoelectric generator integrated in the heat exchanger 8, and air is pumped periodically into the container 5 by the compressor 12 with a DC electric drive 13, controlled by signals from the pressure sensor 24. Thus, periods of forced heating and natural cooling of the engine 1 alternate, ensuring its constant readiness for starting and receiving loads. In this case, the engine itself does not start for self-heating, and special additional devices for its heating are not used.

After starting the engine, reaching its rated speed and turning it on under load, the electric machine 11 is put into operation in the generator mode. The electricity generated by the electric machine 11 can be used to recharge the battery 15 or for direct supply to consumers through a frequency and voltage converter 16. The presence of the converter 16 provides a constant voltage and constant frequency AC power supply when the engine is running at any speed. Electricity to the consumer can also be supplied when the engine is not running, when the converter 16 receives power from the battery.

When the engine 1 is operated only on the electric machine 11, its rotational speed is set constant, and electricity can be supplied to consumers directly from the electric machine 11. In this case, the converter 16 switches to parallel operation with the electric machine 11. Compared to the sequential switching mode of the converter 16 and the electric machines 11 in transport mode, parallel switching them on when engine 1 is used only for generating electricity allows you to remove much more from electric machine 11 shuyu power than the inverter 16. Switching power converter 16 to the serial or parallel operation of the electric machine 11 is performed on a signal from the control unit 14 depending on the engine operating condition 1.

When the engine 1 is operated due to utilization of the heat of its exhaust gases, water vapor is generated in the heat exchanger 8. Working in the mode of a steam generator, shell-and-tube heat exchanger 8 allows you to supply steam from the annular space to consumers. The water supply in the heat exchanger 8 is replenished by the return of condensate or by additional supply of fresh water from an external source. The operation of the heat exchanger 8 in the evaporative mode is a favorable basis for installing a thermoelectric generator in it, since in this case a significant and stable temperature difference in the housing elements is ensured. Thus, the additional generation of thermal and electric energy in the heat exchanger 8 contributes to a significant increase in the efficiency of the engine.

When the engine 1 is operating at low loads, the heat of its exhaust gases may not be enough for the needs of heat supply. In this case, the control device 14, upon a signal from the consumer of thermal energy, by turning on the electric valves 20, 21 and the electro-filling device 23, provides for the preparation of an additional working fluid, a heat carrier, in the electric torch device, which ensures an increase in steam production.

During the operation of an engine with a variable load, significant fluctuations in its rotational speed are possible, which is extremely undesirable, especially when working on an electric generator (as part of a diesel generator set). In order to exclude significant fluctuations in speed during load surges, engine 1 is equipped with a capacity of 5 with an air supply. When a significant load is thrown by a signal from the sensor of the limit position of the injection pump rail, the control device 14 gives a command to pulse open the electrovalve of the air supply to the engine inlet. In this case, a pulsed increase occurs at the inlet to the engine of the amount of the working fluid and at the same time the oxidizing agent, since in addition to neutral nitrogen, air also contains oxygen.

In addition to measures to increase the number of working fluid and oxidizer at the inlet, the claimed technical solution provides measures for supplying an additional working fluid to the turbocharger turbine to reduce the time of spinning of its rotor to the nominal frequency during load surges. To this end, according to the signal from the sensor 4 about the injection pump rail at the maximum fuel supply stop, the control unit 14 generates command pulses for opening the electrovalves 22 and 20, as well as the electro-filling device 23. Due to the lack of oxidizer at the first moment of the transition process caused by an overload of the engine load, in the latter, incomplete combustion of fuel takes place. The pulse supply to the engine exhaust of additional oxidizer (air) from the tank 5 by opening the valve 20, as well as the inclusion of an electro-dropping device 23, simultaneously provide the afterburning of the incompletely burned fuel in the engine and the supply of an additional working fluid to the turbine. In addition, the claimed technical solution provides for the use as an additional working fluid of steam supplied from the heat exchanger 8 to the turbine 7 by means of a pulse opening of the electrovalve 22.

Compared with the closest analogue, where the turbocompressor rotor is twisted by an electric machine, the claimed technical solution provides high speed due to the lack of electromechanical energy conversion, as well as significantly higher power supplied to the rotor. The power of the electric machine at the closest analogue is limited by the discharge characteristics of starter batteries (from 10% to 15% of engine power). When the efficiency of the internal combustion engine is 30-45% for steam production, up to 20-30% of the energy of the fuel burned in the engine can be additionally used, which makes it possible to expend power comparable to the capacity of the engine itself to spin the rotor.

Instead of spinning the rotor of the turbocharger in the claimed technical solution, the electric machine 11 is used to transmit power and stabilize the engine speed during load surges and overloads. Such a solution allows the use of a synchronous power generator — the engine of generator sets — as a reversible electric machine. When the load is charged, as well as when the engine is overloaded by the signal of the active current sensor 18 or the fuel rail position sensor 4, the control unit 14 supplies a command pulse to the converter 16 to transfer it from the charge mode of the battery 15, which is set when the engine is operating at partial loads, in the mode of their discharge to the electric machine 11 (through the Converter 16). In this case, the converter operates in parallel with the electric machine, generating additional electric power of alternating current due to the energy of the battery 15.

When using 15 starter batteries as an energy storage device, the additional power supplied to the network during load surges and overloads can be 10-15% of the engine power. If we allow a possible short-term 200% overload of the converter, then the additional power given to them during load surges can reach 20-30% of the motor power, which can be considered sufficient to ensure transient operation of the motor.

In addition to providing transient engine operation modes, such as preheating, starting, load shedding, the claimed technical solution also allows to increase the efficiency of engine use at low loads and during overloads. The use of the converter 16 in stationary modes of engine 1 as an energy storage device can significantly reduce fuel consumption due to the equalization of the schedule of electrical loads (reduction of operating time at low loads and with overload).

Also, the utilization of the engine exhaust heat in the heat exchanger 8, which is accompanied by the generation and supply of steam to consumers, as well as the additional generation of electricity by the thermoelectric generator built into the heat exchanger 8, also contributes to the economical use of the engine.

In addition to the modes of dumping-loading of the engine load, the supply of an additional working fluid (air) to the engine inlet, twisting of the turbocompressor rotor by an additional working fluid, and also transferring additional power to the engine shaft from the battery can be performed in other engine operating modes, accompanied by a violation of the internal cylinder processes mixture formation and fuel combustion, for example, in acceleration-braking cycles, during overloads, operation under abnormal environmental conditions (in tunnels, car yer). Moreover, in the “hot reserve” mode of the engine, it becomes possible to additionally generate and supply electric and thermal energy to the consumer.

The process of preparing the working mixture supplied to the engine inlet is carried out according to the claimed method in the following sequence.

1. Based on a signal to start the engine or to switch on from the “hot standby” mode, the control device 14, by supplying a signal to the electrovalve 19, provides additional air to the cylinders for reliable ignition of the fuel.

2. At all transitional modes, accompanied by the release of the rail at the maximum fuel supply stop, by the signal from the sensor 4 of the limit position of the injection pump rail, the control device 14 generates a pulse to open the electric valve 19 for supplying additional air to the cylinders. The supply of additional air is stopped by a signal from the sensor 4 after the injection pump rail has gone from the maximum supply stop. In other operating conditions, not accompanied by the release of the rail at the stop of the maximum fuel supply, the working mixture is prepared by compressing atmospheric air in the compressor.

The process of preparing the working mixture supplied to the turbine 7 of the turbocharger of the engine is carried out according to the claimed method in the following sequence.

In the preheating and “hot reserve” modes, according to the signal from the engine temperature sensor 17, the control device 14 sends signals to open the fuel solenoid valves 21 and air 20 to the electroflame device 9, as well as to turn on the electroslip device 23. The high-temperature gas formed as a result of fuel combustion the mixture is fed to a heat exchanger 8, where it gives off the heat used to heat water, prepare steam and at the same time generate electricity to charge the battery 15. By reducing the temperature required to start the engine by a signal from the sensor 17, the control device 14 provides signals to close the solenoid valves 20 and 21 and turn off the electro-dropping device 23.

In transient conditions, leading to the injection pump rail at the maximum fuel supply stop, by a signal from the sensor 4, the control device 14 provides signals for opening the electrovalves 22 and 20, as well as the inclusion of the electro-filling device 23. In this case, the working mixture supplied to the turbine input is formed by mixing the exhaust gases of the engine, the additional gas mixture obtained from the afterburning of incompletely burned fuel in the electric torch device 9 and steam in the heat exchanger 8. When the rail leaves the stop of the maximum supply by signal 4 at the sensor control unit 14 sends a signal for closing the solenoid valves 20 and 22, as well as disabling elektrozapalnogo device 23.

When operating at low (partial) loads and insufficient steam production in the heat exchanger 8, the control device 14 generates a signal to open the solenoid valves 20 and 21, as well as to turn on the electro-filling device 23, upon the signal from the heat energy consumer. The working mixture is supplied to the heat exchanger 8 and then to a turbine 7 is formed by mixing the exhaust gas of the engine with an additional gas mixture formed by burning fuel in an electric torch device. In other operating conditions, the engine exhaust gas is used as the working mixture supplied to the turbine 7.

Claims (2)

1. The method of operation of the internal combustion engine by inlet of compressed air, its compression, injection and combustion of fuel, exhaust gas, supply in transition modes of an additional working fluid by a control signal generated at the time of reaching maximum fuel supply in a given mode, the compression ratio of air in transient conditions increase by tightening the rotor of the turbocompressor, and in transient conditions of starting and maintaining the engine in the “hot reserve” before supplying fuel and compressed air to the cylinders the engine is heated, characterized in that the rotor of the turbocharger is twisted in transient conditions by steam generated due to the heat of the exhaust gases in the heat exchanger installed on the engine exhaust and an additional working fluid obtained by burning at the engine exhaust before the heat exchanger a mixture of air from the air tank and exhaust gases the engine, the crankshaft of the engine in transient conditions and working with overload tighten up an electric machine powered by a battery through the conversion In this case, compressed air from the tank with its reserve is used as an additional working fluid supplied to the engine inlet, which is replenished by an electric compressor, and an additional working fluid is introduced into the exhaust gases of the engine during transient conditions and when operating at low loads - heat carrier prepared by burning at the engine outlet in front of the heat exchanger a mixture of fuel supplied under pressure from a tank with its reserve, and a mixture of air from an air tank, as well as of running engine gases, the rechargeable batteries are charged from a thermoelectric generator built into the heat exchanger, and they are charged when the engine is running at light loads from an electric machine through a frequency and voltage converter, while at all operating modes, consumers are supplied with electricity from the frequency and voltage converter, as well as steam from the heat exchanger. 2. An internal combustion engine comprising at least one cylinder with a piston placed therein kinematically connected to the shaft, a turbocharger in which the turbine outlet and compressor inlet are connected to the atmosphere, an inlet pipe, an exhaust pipe, a hydrocarbon fuel supply line to the cylinders equipped with a high-pressure fuel pump equipped with a maximum fuel supply sensor, a high-pressure tank connected to an electrovalve for supplying a gaseous oxidizer to the engine, a rechargeable battery a battery, a control device, the control outputs of which are connected to the limit switch of the injection pump rail and the temperature sensor, and the control inputs with an electrovalve for supplying a gaseous oxidizer to the engine inlet, an electrovalve for supplying fuel, as well as a frequency and voltage converter, an electroflame device equipped with an electro-ignition device for igniting a fuel-air mixtures, a tank with a fuel reserve, a fuel solenoid valve connected to an electric torch device, an electric machine, connected through a frequency and voltage converter with a battery, a temperature sensor mounted on the engine, characterized in that it further comprises an air compressor equipped with a direct current drive electric motor, an electro-valve for supplying gaseous oxidizer (air) to an electro-torch device, an electro-valve for supplying steam to the turbocharger turbine , shell-and-tube heat exchanger with a supply of water in the annulus and a built-in thermoelectric generator, electric load sensor (ac current) installed in the frequency and voltage converter, an air pressure sensor installed in the high-pressure tank, the electric machine being kinematically connected to the crankshaft of the engine, the output of the high-pressure tank is simultaneously connected to the air electric compressor, the upper part of the tank with fuel supply, through a valve supplying air to an electric torch device with a first gas inlet of an electric torch device, through an oxidizer supply valve to the engine inlet with its intake pipe also connected to the compressor outlet, the second gas inlet of the electric torch device is connected to the exhaust pipe (collector) of the engine, and the outlet through the pipe space of the heat exchanger is connected to the turbine inlet, which is also connected through the steam supply solenoid to the upper part of the annular space of the heat exchanger, and in the heat exchanger, the thermoelectric generator is connected to the battery, and the additional control inputs of the control device are connected to the pressure sensor and sensors com of the electric load, and additional control outputs are connected to the electric compressor motor, the steam supply electrovalve and the air supply electrovalve to the torch device.