RU2193682C2 - Method to control working processes in multifuel internal combustion engine - Google Patents

Abstract

FIELD: mechanical engineering; internal combustion engines. SUBSTANCE: invention is designed for organizing working process in direct injection internal combustion engines. proposed method is based on injection of fuel into combustion chamber at compression stroke, formation of hydrocarbon mixture from air charge and fuel injected into combustion chamber through plasmoelectrochemical reactor with simultaneously delivering chemically active air plasma flow from low temperature plasma generator. This flow provides plasmoelectrochemical pyrolysis in reactor and excitation of molecules and atoms of fuel with subsequent self igniting at mixing with air charge in combustion chamber. EFFECT: enlarged dynamic range of control action on working processes in multifuel engine, simplified realization of control action. 1 dwg

Description

 The invention relates to the field of engine building and is intended for organizing a working process in internal combustion engines with direct fuel injection.

 A known method of controlling the working processes of an internal combustion engine, the technical implementation of which is an internal combustion engine [1]. A depleted air-fuel mixture enters the combustion chamber of this engine, which is ignited by a fuel plasma torch obtained in the prechamber.

 The disadvantage of this method is that during operation of the internal combustion engine, fuel economy and environmental friendliness of the fuel are not ensured, since the air drawn in through any carburetor is dosed only by the volume and not by the mass necessary to ensure economical fuel consumption and an environmentally friendly process combustion.

 The closest known technical solution as a prototype is a method of controlling the working processes of a multi-fuel internal combustion engine, based on the injection of fuel into the combustion chamber at a compression stroke, the formation of a hydrocarbon mixture together with air charge and its ignition using an electric spark plug located either in the pre-chamber or directly in the combustion chamber [2]. In this case, the device that implements the prototype contains an electronic engine control system, air and fuel supply systems, a power supply unit and a direct fuel injection system into the combustion chamber. Through the use of a lean fuel mixture, in which 40-50 parts of air falls on one part of gasoline, computerization of the engine control process and periodic regeneration of the catalyst ensure the economy and environmental friendliness of a vehicle with such an engine.

 The disadvantage of the prototype lies in the narrow dynamic range of the control action on the working processes of a multi-fuel internal combustion engine, which is given by a limited interval of a possible change in the composition of the combustible mixture (α <3.0) and the need for precision dosing of fuel and air, as well as setting high-precision moments of electric spark ignition . Another disadvantage of the prototype is the complexity of the technical implementation of the control of the internal combustion engine for fuels of a wide fractional composition and its industrial production with a narrow range of tolerance deviations of the elements of the cylinder-piston group. The narrow dynamic range of the control action on the working processes of the internal combustion engine, the high cost and complexity of technical implementation reduce the efficiency and environmental friendliness of the internal combustion engine.

 The aim of the invention is to expand the dynamic range of the control action on the working processes of a multi-fuel internal combustion engine by automatically regulating not only the composition of the combustible mixture (up to α> 3.0), but also its chemical activity, as well as simplifying its technical implementation by reducing requirements to high-pressure fuel equipment and replacing a complex electrospark system with a plasma-electrochemical technology for the pyrolysis of hydrocarbon fuel of wide fractional composition with the next direct injection of pyrolysis products into the combustion chamber for self-ignition.

 The essence of the invention lies in the fact that in addition to the known and general operations based on the injection of fuel into the combustion chamber on a compression stroke and the formation of a hydrocarbon mixture together with the air charge, a new set of operations is proposed, which is characterized in that fuel is injected into the combustion chamber through a plasma electrochemical reactor with the simultaneous entry there from a low-temperature plasma generator of a stream of chemically active air plasma, which provides a plasma electrochemical in the reactor pyrolysis and excitation of molecules and fuel atoms with its subsequent self-ignition with stirring with an air charge in the combustion chamber.

 The novelty of the invention lies in the fact that the fuel is injected into the combustion chamber through a plasma electrochemical reactor with the simultaneous flow of chemically active air plasma from the low-temperature plasma generator, which provides plasma electrochemical pyrolysis and excitation of fuel molecules and atoms with its subsequent self-ignition with stirring with an air charge in the combustion chamber, which allows to expand the dynamic range of the control action on the working processes of multi-fuel internal combustion engine and simplify its technical implementation.

A functional diagram of a device that implements the proposed method for controlling the working processes of a multi-fuel internal combustion engine is shown in the drawing, where it is indicated:
1 - electronic engine management system; 2 - measuring channels (sensors); 3 - controller; 4 - actuators; 5 - a system for supplying air to a low-temperature plasma generator; 6 - power supply unit: 7 - fuel supply system to the plasma chemical reactor; 8 - air supply line; 9 - low-temperature plasma generator; 10 - fuel dispenser; 11 - fuel supply line; 12 - plasma electrochemical reactor; 13 - air supply channel; 14 - a piston; 15 - combustion chamber; 16 - shutoff valve; 17 - chemically active combustible mixture.

 In the initial state, the electronic engine control system 1, containing measuring channels (sensors) 2 connected in series, controller 3 and actuators 4, is connected to the corresponding inputs of the air supply system 5 to the low-temperature plasma generator, power supply unit 6 and fuel supply system 7 c plasma chemical reactor. The air supply line 8 is connected to one input of the low-temperature plasma generator 9, the output of the power supply unit 6 is connected to the other input thereof. The fuel metering device 10 is included in the fuel supply line 11 for the plasma electrochemical reactor 12. The air supply channel 13 is directed through the valves to the piston 14 of the combustion chamber 15 into which a flow of reactive combustible mixture 17 is directed through a shutoff valve 16.

 A device that implements the proposed method of controlling the working processes of a multi-fuel engine, operates as follows.

 The low-temperature plasma generator 9 consumes the air and electric energy necessary for the formation of an air low-temperature plasma stream, which at the output of the low-temperature plasma generator 9 becomes chemically active, since it consists of charged particles, excited atoms and molecules of air compounds. The flow of air low-temperature plasma under excess pressure enters the plasma electrochemical reactor 12. Due to the high chemical activity of the air low-temperature plasma in the plasma electrochemical reactor 12, high-speed (with mixing speed) plasma-chemical pyrolysis of the fuel occurs. In this case, exothermic oxidation of a part of the fuel with the release of additional heat, destruction and excitation of molecules and atoms of the fuel is observed.

 At a point in time specified by the electronic engine control system of the engine 1, the required fuel charge is injected into the combustion chamber 15 through a plasma electrochemical reactor 12 and a shut-off valve 16. As a result of these processes, a chemically active multiphase fuel stream 17 is formed at the outlet of the plasma-electrochemical reactor 12, mounted directly on the cylinder head and connected to the combustion chamber 15, which self-ignites when interacting with a charge of air in the combustion chamber 15.

 The regulatory change in the volume and moment of fuel injection into the combustion chamber 15 through the plasma-electrochemical reactor 12 is carried out cyclically according to the commands of the electronic control system of the engine 1, according to the established algorithm and the order of operation of the cylinders of the internal combustion engine. Air and electrical energy can be consumed by the low-temperature plasma generator 9 both continuously and discretely, in accordance with the fuel consumption pattern.

 The low-temperature plasma generator 9 consumes about 1% of the air entering the engine and electric power, which is about 0.5% of the engine output. The coefficient of excess air in the plasma electrochemical reactor 9 depending on the thermal state of the structure and engine operating conditions, the type of fuel used and the electric energy consumed by the low-temperature plasma generator 9 can vary in a wide range from 0.001 to 0.4. In this case, the operation algorithm of the electronic engine control system 1 is organized so that in any engine operation mode, a chemically active multiphase flow of combustible hydrocarbon fuel mixture 17 enters the combustion chamber 15 through the plasma-electrochemical reactor 12, which, when interacting (during mixing in the combustion chamber 15), self-igniting air charge.

 Industrial applicability of the claimed invention is confirmed by the fact that the process of plasma chemical technology is known in [3], according to the invention in 1998-2000 Technical documentation has been developed, prototypes of internal combustion engines have been manufactured and tested on automobiles of the Volga Automobile Plant.

 The positive effect of the use of the invention is that the dynamic range of the control action on the working processes of a multi-fuel internal combustion engine is expanded due to the fact that, in addition to the well-known computer dosing by the amount of intake air for combustion and fuel, an additional automatic control of the chemical activity of hydrocarbon fuel by its destruction with the help of air low-temperature plasma.

 Simplification of the technical implementation of the claimed method is achieved by reducing the requirements for high-pressure fuel equipment and replacing a complex electrospark system with a plasma-electrochemical technology for the pyrolysis of hydrocarbon fuel of wide fractional composition with the subsequent direct injection of pyrolysis products into the combustion chamber for their self-ignition.

 Invariance to various types of hydrocarbon fuels used is ensured by its destruction with the help of air low-temperature plasma, which is known in [4].

Literature
1. US patent 4332223, IPC F 02 P 23/00, F 02 B 19/10, F 02 B 23/00, 1982 (analogue).

 2. Vorobyov-Obukhov A., Dialectics of injection. The magazine "Behind the wheel", 8, 2000, p. 56-58 (prototype).

 3. RF patent 2051289, IPC F 02 M 27/00, 1992

 4. Pyrolysis, Brief Chemical Encyclopedia, Moscow: Soviet Encyclopedia, 1964, p. 1069-1082.

Claims (1)

 A method of controlling the working processes of a multi-fuel internal combustion engine, based on the injection of fuel into the combustion chamber on a compression stroke and the formation of a hydrocarbon mixture together with the air charge, characterized in that the fuel is injected into the combustion chamber through a plasma electrochemical reactor while chemically flowing therefrom a low-temperature plasma generator active air plasma, which provides plasma electrochemical pyrolysis and excitation of molecules and atoms in the reactor fuel with its subsequent self-ignition with stirring with an air charge in the combustion chamber.