RU2239708C2 - Internal combustion engine - Google Patents

Abstract

FIELD: mechanical engineering; internal combustion engines.

SUBSTANCE: proposed engine has main combustion chamber, vortex antechamber in form of solid of revolution and connected with main chamber by channel, fuel nozzle installed in antechamber, and piston with shaped displacer on piston crown made of material with memorized shape effect. Iron and nicker-based allow can be used as such material. When engine is not warmed at partial loads said shaped displacer turns through some angle, thus providing swirling of air in antechamber.

EFFECT: reduced fuel consumption of engine and toxicity of exhaust gases at partial loads.

2 cl, 4 dwg

Description

The invention relates to mechanical engineering, in particular to engine building, and in particular to internal combustion engines.

Known piston engine [1] with fuel injection into the pre-chamber and the ejection of the burning mixture from the pre-chamber into the cylinder using a central protrusion with a cylindrical part, a pre-chamber with a fuel nozzle connected to the main combustion chamber using a bypass channel with a cylindrical part.

Optimization of the amount of heat removed from the protrusion can improve the efficiency of the proposed engine due to the stability of the cross section of the bypass channel and the stability of ignition, as well as the completeness of combustion of the charge. In addition, heat removal from the protrusion prevents its burning, which also allows to increase the reliability of the engine.

The disadvantage of this design is the lack of twisting of the air charge in the prechamber, which reduces the quality of preparation of fuel for combustion and affects the efficiency of the engine. Another disadvantage is the stability of the cross section of the bypass channel, which is ineffective in partial engine operation modes.

Also known [2] is an internal combustion engine comprising a cylinder, a piston disposed therein with a bottom provided with a protrusion, a cylinder head, intake and exhaust channels with valves, a main combustion chamber bounded by a cylinder wall, its head and piston bottom, and a pre-chamber with a narrower a neck located in the head, overlapped by the protrusion of the piston bottom when the latter is at top dead center and equipped with a nozzle, the inlet and outlet channels being placed in the main combustion chamber, characterized in that w improve efficiency, it is provided with a purge passage with a valve positioned in the precombustor against the neck, and a purge passage communicated with the discharge passage.

The disadvantage of this technical solution is that the cross section of the throat passage is selected for the rated power mode and for partial loading modes is too large, which leads to a deterioration in fuel atomization, an increase in the diameter of the fuel droplets and, ultimately, to a deterioration in the combustion process and an increase in consumption partial engine fuel.

In addition, this design also does not ensure the twisting of the air charge in the pre-chamber, which reduces the quality of fuel preparation (charge turbulence) and, thereby, affects the efficiency of the engine.

Also known [3] is an internal combustion engine comprising a main combustion chamber and a vortex pre-chamber connected to the main chamber by means of a connecting channel, the piston having a cylindrical protrusion located at the position of the piston at top dead center in the pre-chamber.

The disadvantage of this technical solution is the lack of air charge swirl in the prechamber, which leads to a decrease in engine efficiency in partial operating modes.

The closest technical solution to the claimed invention is an internal combustion engine [4], in which the fuel supply element is made in the form of a nozzle with a single-hole atomizer installed in the upper part of the prechamber in its center, and a displacer is attached to the piston bottom.

The engine has a vortex chamber in the form of a body of revolution, connected to the main chamber by means of a connecting channel, a fuel nozzle installed in the pre-chamber, and a piston with a shaped displacer on the bottom located in the channel with a gap.

The piston protrusion is not cylindrical, but is provided with grooves and protrusions, the generators of which are parallel to the axis of the cylinder. The longitudinal grooves on the displacer and the neck do not change the characteristics of air movement and do not create air swirl in the prechamber.

The disadvantage of this technical solution adopted as a prototype is that when the engine speed is reduced in partial engine operation, air consumption is significantly reduced, as a result of which the combustion process worsens and it becomes necessary to twist (turbulize) the air charge in the prechamber.

The purpose of the invention is to increase engine efficiency and reduce exhaust gas toxicity in partial engine operation modes.

The goal is achieved in an internal combustion engine, which contains a main combustion chamber formed by the surfaces of the piston, liner and cylinder head, a vortex pre-chamber in the form of a body of revolution, connected to the main chamber by means of a connecting channel, a fuel nozzle installed in the pre-chamber, and a piston with a shaped displacer on a bottom placed in a channel with an annular gap.

New in the internal combustion engine is the implementation of a shaped displacer from a material having a shape memory effect, for example, from an alloy based on iron and nickel.

Figure 1 shows the engine, a longitudinal section; figure 2 is a section aa, figure 3 shows a section aa after martensitic transformation while lowering the temperature inside the combustion chamber; figure 4 - engine, a longitudinal section after martensitic transformation of the protrusion of the piston.

The engine contains a main combustion chamber 1, connected to the pre-chamber 2 by a connecting channel 3, into which a shaped displacer 4 enters at top dead center. Equidistant grooves 6 are made on the neck 5 and the shaped displacer 4 parallel to the axis of the cylinder. The pre-chamber 2 is equipped with a nozzle 7.

The piston 8 is provided with a cylindrical protrusion in the form of a shaped displacer 4 on the bottom, placed in the channel 3 with an annular gap. The working fluid from the pre-chamber 2 flows into the main combustion chamber along the annular channel 3 formed by the neck 5 and the shaped displacer 4. On the shaped displacer 4 there are equidistant grooves 6.

The engine operates as follows. The nozzle 7 injects fuel into the pre-chamber 2. During the combustion, the mixture of fuel and air enters the main chamber 1. The longitudinal grooves on the figured displacer and the neck do not change the characteristics of the air movement, they do not create additional air swirl.

The equidistant arrangement of the grooves allows for relocation of the piston to exclude the contacts of the figured displacer with the surface of the neck (figure 2).

In partial operating modes, the air flow rate, for example a naturally aspirated diesel engine, depends only on the number of revolutions of its crankshaft. At the same time, the air flow can be so reduced that without air swirling in the pre-chamber, the engine's efficiency will deteriorate significantly. On the other hand, at low engine operating conditions with a significant decrease in fuel supply, the temperature in the combustion chamber decreases. The temperature of the shaped displacer 4, made of a material with a shape memory effect, decreases, a martensitic transformation occurs in it, as a result of which the shaped displacer 4 rotates by its free end by a certain angle (Figs. 3 and 4), ensuring air swirling in the pre-chamber and, thereby , reducing fuel consumption and exhaust gas toxicity at partial engine operation modes.

With an increase in the cyclic supply of fuel and the speed of the crankshaft in the engine, the temperature of the charge in the pre-chamber 2 increases, the temperature of the shaped displacer 4 rises, and the reverse martensitic transformation occurs in it. As a result, the shaped displacer 4 takes its former shape.

The dimensions and shape of the parts of the combustion chamber take on the previous values and ensure high-quality engine operation at rated and close operating modes.

Thus, the use of the proposed internal combustion engine contributes to the improvement of economic performance of the engine in partial operating modes, without impairing the performance of the nominal and close operating modes of operation.

Sources of information

1. A.S. USSR No. 1663209, publ. 07/15/91, bull. No. 26.

2. A.S. USSR No. 1372076, publ. 02/07/88, bull. No. 5.

3. A.S. USSR No. 1137224, publ. 01/30/85, bull. Number 4.

4. A.S. USSR No. 1318703, publ. 06/23/87, bull. Number 23.

5. A.S. Tikhonov, A.P. Gerasimov, I.I. Prokhorov. Application of the shape memory effect in modern engineering. - M.: Mechanical Engineering, 1981, 80 p.

Claims (2)

1. An internal combustion engine comprising a main combustion chamber formed by the surfaces of a piston, a sleeve and a cylinder head, a vortex pre-chamber in the form of a body of revolution, connected to the main chamber by means of a connecting channel, a fuel nozzle installed in the pre-chamber, and a piston with a shaped displacer on the bottom located in a channel with an annular gap, characterized in that the shaped displacer is made of a material having a shape memory effect. 2. ICE according to claim 1, characterized in that an alloy based on iron and nickel is used as a material having a shape memory effect, while in the unheated state at partial engine operation modes, the shaped displacer is rotated by a certain angle, providing air swirling in precamera.

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