JP2000179412A - Internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an internal combustion engine which can increase a compression ratio without generating knocking, obtain high engine efficiency, and meet to exhaust limit requirement. SOLUTION: This internal combustion engine has followings. A cylinder block 1 has a cylinder wall. A cylinder head 3 is arranged on the cylinder block 1. A piston 16 is arranged in the cylinder block 1. A combustion chamber 5 is determined by the cylinder wall, the cylinder head 3 and the piston 16. An electric field application means 2 applies an electric field during combustion of an engine.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an internal combustion engine,
More specifically, the present invention relates to an internal combustion engine that can improve the combustion efficiency of the internal combustion engine.

[0002]

2. Description of the Related Art Hazardous exhaust gas emitted from a vehicle's internal combustion engine pollutes air and gradually degrades the environment. As a result, laws and regulations that limit emission standards are becoming stricter. For this reason, various countermeasures have been adopted for the engine to meet the required emission standards without reducing the power. As an example of the measure, there is a means for increasing the compression ratio of the engine.

[0003]

However, in the conventional internal combustion engine described above, if the compression ratio is too high, the power increases, but knocking occurs in the engine. Therefore, there is a problem that the increase in the compression ratio is limited.

Accordingly, the present invention has been made in view of the above-mentioned problems, and an object of the present invention is to prevent the engine from knocking, to increase the compression ratio, to obtain high engine efficiency, and to reduce exhaust emissions. An object of the present invention is to provide an internal combustion engine that meets a restriction request.

[0005]

Means for Solving the Problems In order to achieve the above object, according to the present invention, in an internal combustion engine, there is provided a cylinder block having a cylinder wall, and a cylinder head disposed on the cylinder block. A piston disposed in the cylinder block, a combustion chamber formed from the cylinder wall, the cylinder head and the piston, and electric field applying means for applying an electric field to the combustion chamber during engine combustion. Features.

The electric field applying means includes a conductor member arranged to apply an electric field to the combustion chamber, and a voltage supply device for supplying a voltage to the conductor member.

[0007] The conductor member has a nichrome wire installed in a cylinder wall.

[0008] Preferably, the nichrome wire has a thickness of about 1.0 mm.

[0009] The internal combustion engine includes an electronic control unit for controlling the operation of the voltage supply device.

[0010] The electric field is a DC electric field, preferably about 2 to 9 kV, more preferably 8 kV.

[0011]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. As is well known, when an electric field is applied to the flame in a direction perpendicular to the gas flow direction and the direction of the electric field lines, the flame tilts toward the cathode. This is because positive ions in the flame collide with other chemical species in the flame while moving toward the cathode of the electric field to generate kinetic energy. That is, the moving ions are in the flame concentration field (density field).
field and fluid field to excite chemical species. The present invention has been made using such a principle. That is, in the embodiment of the invention, a device for applying an electric field to the combustion chamber is applied to the internal combustion engine of the vehicle in order to improve the combustion efficiency of the engine. More specifically, an electric field was applied to the flame generated in the combustion chamber.

FIG. 1 is a partial sectional view of an internal combustion engine having an electric field applying means according to a preferred embodiment of the present invention. The engine of the present invention includes a cylinder block 1 and a cylinder head 3. The cylinder block 1 and the cylinder head 3 form a combustion chamber 5. Reference numeral 2 denotes an electric field applying unit. Electric field applying means 2 includes a conductor member 4 and a voltage supply device 6.

The conductor member 4 of the electric field applying means 2 is formed in an annular groove 10 provided in an annular insulator 12 inserted into the cylinder wall of the cylinder block 1.
The conductor member 4 is preferably made of a nichrome wire having a diameter of about 1.0 mm. The annular groove 10 is 1.0 m
In order to embed the conductor member 4 having a diameter of m, the conductor member 4 is formed to have a depth of 1.0 mm and a width of 1.0 mm. The voltage supply device 6 of the electric field applying means 2 includes an electronic control device 14
And supplies a high voltage to the conductor member 4. In the drawings, reference numeral 16 denotes a piston, reference numeral 18 denotes an intake / exhaust valve assembly, and reference numeral 20 denotes a spark plug.

In the embodiment of the present invention, when the presence of a flame in the combustion chamber 2 is detected by a flame detection sensor (not shown), the electronic control unit 14 activates the voltage supply unit 6 to activate the conductor. A voltage of about 6 kV is supplied to the member 4. The conductor member 4 supplied with the voltage applies an electric field to the flame in the combustion chamber. Applying an electric field to the flame increases the speed of flame propagation, thereby improving engine combustion and preventing knocking.

More specifically, when an electric field is applied to the flame ignited by the flame nucleus generated by the spark plug 20 and propagating into the combustion chamber 5, the ions move into the flame by the applied electric field and collide with each other. . The collision between the ions increases the flame propagation speed, and the ions in the already burned gas move to the unburned gas to change the chemical reaction of the unburned gas. As a result, the temperature of the flame is kept constant, and knocking of the engine is suppressed.

A series of experiments were performed using a rapid compressor engine with a combustion enhancer. The details of the compression engine are as follows. Driving source: Air Inner diameter of cylinder: 51 mm Stroke: 211 mm Electrode: Nichrome wire having a diameter of 1.0 mm and 28 mm
The nichrome wire is inserted into a groove provided in the cylinder wall, and the copper is mounted on the cylinder head. The experimental conditions are as follows. Cylinder wall temperature: 296K Initial pressure of mixed gas (P0): 0.1 Mpa Compression ratio (ε): 7.75 Equivalent ratio (ψ): 1.0 Fuel: n-butane DC voltage of 0 to 8 kV is applied. Experiments. In order to measure the pressure in the combustion chamber, a piezoelectric pressure sensor (50
A PCB 102A04 having a natural frequency of 0 kHz was used. The cylinder head was made of quartz glass so that the combustion process could be imaged. The shooting speed is 2,000
It was 0 fps.

The results of the experiment will be described below with reference to the accompanying drawings. FIG. 2 is a graph showing a change in knocking intensity KI (Z) according to the level of the electric field applied to the combustion chamber of the engine. Knocking strength KI (Z) is shown as follows. KI (Z) = Σ (P _(i) −P _mean ) ² / (P _k −
P _o ) P _(i) is the combustion pressure, P _mean is the pressure obtained by subjecting the time series data of the combustion pressure to a 3 kHz low-pass filter processing, P _k is the pressure at the time of occurrence of knocking, and P _o Is the pressure when spark ignition occurs.

When no electric field was applied to the combustion chamber, the knocking strength was about 3.3 bar. When a 2 kV electric field was applied, the knocking intensity decreased to about 2.7 bar. When an electric field of 4 kV was applied, the knocking intensity sharply decreased to about 1 bar. Further, when an electric field of 8 kV was applied, the knocking intensity was reduced to 85% as compared with the knocking intensity when no electric field was applied.

FIG. 3 is a graph showing the effect of an electric field on flame propagation. The area of the burned part obtained from the direct photograph of the flame propagation and rendered dimensionless by the area of the combustion chamber is defined as the burned area ratio. As shown in this graph, 6 kV
When the electric field is applied, the burned portion becomes larger than when no electric field is applied. More specifically, 5 minutes from the start of ignition
Up to ms, the burned portion when the electric field of 6 kV was applied was the same as the burned portion when the electric field was not applied. However, 5 ms after the ignition, the burned portion when the electric field of 6 kV was applied became larger than the burned portion when the electric field was not applied.

[0020]

As is apparent from the above description, according to the present invention, when a certain electric field is applied to the flame in the combustion chamber, the positive ions in the flame move toward the cathode by the Coulomb force of the electric field. Collides with other species in the flame.
As a result, kinetic energy is generated, and the kinetic energy increases the flame propagation speed and improves the combustion efficiency.

Here, the present invention has been described based on the embodiments of the invention. However, the present invention is not limited to the embodiments, but includes all modifications included in the scope and spirit of the claims.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view illustrating an engine having an electric field application device according to an embodiment of the present invention.

FIG. 2 is a graph showing the effect of an electric field on knocking intensity KI (Z).

FIG. 3 is a graph showing the effect of an electric field on flame propagation.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder block 2 Electric field application means 3 Cylinder head 4 Conductor member 5 Combustion chamber 6 Voltage supply device 10 Annular groove 12 Annular insulator 14 Electronic control unit 16 Piston 18 Intake / exhaust valve assembly 20 Spark plug

Claims (9)

[Claims] A cylinder block having a cylinder wall; a cylinder head disposed on the cylinder block; a piston disposed in the cylinder block; and a combustion chamber formed from the cylinder wall, the cylinder head, and the piston. And an electric field applying means for applying an electric field to the combustion chamber during combustion of the engine. 2. An electric field applying means comprising: a conductor member arranged to apply an electric field to a combustion chamber; and a voltage supply device for supplying a voltage to the conductor member. Item 6. The internal combustion engine according to Item 1. 3. The internal combustion engine according to claim 2, wherein the conductor member includes a nichrome wire installed in a cylinder wall. 4. The internal combustion engine according to claim 3, wherein said nichrome wire has a thickness of about 1.0 mm. 5. The internal combustion engine according to claim 2, further comprising an electronic control unit that controls an operation of the voltage supply device. 6. The internal combustion engine according to claim 1, wherein the electric field is a DC electric field. 7. The internal combustion engine according to claim 1, wherein the electric field is 2 kV or more. 8. The internal combustion engine of claim 1, wherein said electric field is between about 2 and 9 kV. 9. The internal combustion engine of claim 1, wherein the electric field is about 8 kV.