阅读说明：本技术 一种燃料空气分离主动控制式点火室系统 (Fuel-air separation active control type ignition chamber system ) 是由 朱晶宇 隆武强 田华 于 2021-06-28 设计创作，主要内容包括：本发明公开一种燃料空气分离主动控制式点火室系统,涉及内燃机燃烧技术领域,包括设于点火室顶部的供气支路和供燃料支路；点火室设于气缸盖或点火室适配器单体上,气缸盖或点火室适配器单体上设有火花塞、空气通道和燃料通道,火花塞设于点火室上方,空气通道和燃料通道与点火室连通,供气支路与空气通道连通,供燃料支路与燃料通道相连通；预燃用空气由空气压力泵直接供应,或从发动机本体增压器的下游开设旁路供应,在排气冲程后期或进气冲程前期利用增压器下游和缸内的压差实现点火室换气。经空气压力蓄积室稳压后经过单向安全阀供给空气喷嘴端,实现点火室内的主动扫气,并可以实时控制点火室内混合气组成,以提高燃烧稳定性和可控性。(The invention discloses a fuel-air separation active control type ignition chamber system, which relates to the technical field of combustion of an internal combustion engine and comprises an air supply branch and a fuel supply branch, wherein the air supply branch and the fuel supply branch are arranged at the top of an ignition chamber; the ignition chamber is arranged on the cylinder cover or the ignition chamber adapter monomer, the cylinder cover or the ignition chamber adapter monomer is provided with a spark plug, an air channel and a fuel channel, the spark plug is arranged above the ignition chamber, the air channel and the fuel channel are communicated with the ignition chamber, the air supply branch is communicated with the air channel, and the fuel supply branch is communicated with the fuel channel; the pre-combustion air is directly supplied by an air pressure pump or is supplied by a bypass from the downstream of a supercharger of an engine body, and the pressure difference between the downstream of the supercharger and the inside of a cylinder is utilized to realize the ventilation of an ignition chamber in the later stage of an exhaust stroke or the earlier stage of an intake stroke. After being stabilized by the air pressure accumulation chamber, the mixture is supplied to the air nozzle end through the one-way safety valve, active scavenging in the ignition chamber is realized, and the composition of the mixed gas in the ignition chamber can be controlled in real time, so that the combustion stability and controllability are improved.)

1. A fuel-air separation active control type ignition chamber system is characterized by comprising an air supply branch and a fuel supply branch which are arranged at the top of an ignition chamber; the ignition chamber is arranged on the cylinder cover or the ignition chamber adapter monomer, a spark plug, an air channel and a fuel channel are arranged on the cylinder cover or the ignition chamber adapter monomer, the spark plug is arranged above the ignition chamber, the air channel and the fuel channel are communicated with the ignition chamber, the air supply branch is communicated with the air channel, and the fuel supply branch is communicated with the fuel channel; the ignition chamber is communicated with the main combustion chamber;

the air supply branch comprises a pressure accumulation chamber and an air nozzle, and the air nozzle is arranged in the air channel;

an air guide hole is arranged below the jet orifice of the air nozzle,

one end of the air guide hole close to the ignition chamber is of a tapered structure and extends to the ignition chamber from the jet orifice of the air nozzle along the tangential direction of the wall surface of the ignition chamber;

or the air guide hole is an equal-diameter bent pipe channel and faces to the central axis direction of the ignition chamber;

or the air guide hole is an equal-diameter bent pipe channel and is arranged in an obliquely downward direction, and the axis of the air guide hole is intersected with the axis of the fuel spray hole at a position close to the spark plug in the ignition chamber.

2. The fuel-air separation actively controlled ignition chamber system of claim 1, wherein a one-way relief valve is disposed between the pressure accumulation chamber and the air nozzle.

3. The fuel-air separation actively controlled ignition chamber system of claim 1, where the pressure accumulation chamber is in communication with an air pressure pump or an engine block supercharger.

4. The fuel-air separation actively controlled ignition chamber system of claim 1, wherein the air nozzle is bolted into the air passage.

5. The fuel-air separation actively controlled ignition chamber system of claim 1, wherein the fuel supply branch includes a fuel tank, a fuel low-pressure pump, and a fuel nozzle, which are sequentially communicated by a pipe; the fuel nozzle is disposed within the fuel passage.

6. The fuel-air separation actively controlled ignition chamber system according to claim 5, characterized in that the fuel nozzle is disposed obliquely with its injection port directed toward the side of the air supply branch; the jet orifice of the fuel nozzle is a single-hole or multi-hole or cross jet orifice or outward-opening annular nozzle.

7. The fuel-air separation actively controlled ignition chamber system of claim 5, wherein the fuel nozzle is bolted into the fuel passage.

8. The fuel-air separation actively controlled ignition chamber system of claim 5, wherein the amount of air and the amount of fuel in the ignition chamber and the injection time and the ignition time are precisely controlled, respectively; firstly, spraying partial air to sweep the waste gas in the ignition chamber, and secondly, spraying fuel and the residual air to rapidly mix in the ignition chamber; the proportion of fuel and air in the ignition chamber is adjusted according to the operating condition so as to ensure the combustion stability and avoid knocking; the ignition time is determined by the target combustion phase of the main combustion chamber, the composition of mixed gas in the ignition chamber and the flame jet characteristic.

Technical Field

The invention relates to the technical field of combustion of internal combustion engines, in particular to a fuel-air separation active control type ignition chamber system.

Background

With the gradually strengthened requirements of the energy-saving and emission-reducing regulations, the internal combustion engine for vehicle and ship power and power generation adopts the lean premixed combustion technology more, and the controllability and the stability of the lean premixed combustion can be improved by igniting the lean premixed gas in the main combustion chamber through flame jet flow or hot combustion product jet flow formed by the ignition chamber. Secondly, the ignition chamber structure is adopted in the high-pressure internal combustion engine, so that the combustion rate can be effectively improved, and the obvious effects of avoiding knocking and improving the combustion constant volume degree are achieved. Most ignition chambers are passively scavenged, namely, the intake air flow of the main combustion chamber enters through a small hole at the lower end of the ignition chamber body, so that the ignition chambers are ventilated. However, with the utilization of the large-proportion exhaust gas recirculation technology and the complexity of the main structure of the ignition chamber, the efficiency of passive scavenging is low, and the proportion of the exhaust gas in the ignition chamber is too high, so that the combustion stability is affected.

The lean premixed combustion mode of the internal combustion engine adopts different air fuel proportions under different load working conditions, and the combustibility difference of premixed gas in the main combustion chamber is large. To ensure stable combustion characteristics under transient conditions, precise control of the fuel-to-air ratio within the ignition chamber is required. The conventional method of mixing the fuel and air outside the cylinder and then introducing the mixture into the ignition chamber cannot meet the requirements of accuracy and instantaneity.

Disclosure of Invention

In order to solve the technical problems, the invention provides a fuel-air separation active control type ignition chamber system, which realizes active scavenging in an ignition chamber and can control the composition of mixed gas in the ignition chamber in real time according to information such as load, fuel-air ratio in a main combustion chamber and the like so as to improve combustion stability and controllability. In addition, the scavenging efficiency of the ignition chamber and the forming efficiency of the mixed gas are improved through structural optimization.

In order to achieve the purpose, the invention provides the following scheme:

the invention provides a fuel-air separation active control type ignition chamber system, which comprises an air supply branch and a fuel supply branch, wherein the air supply branch and the fuel supply branch are arranged at the top of an ignition chamber; the ignition chamber is arranged on the cylinder cover or the ignition chamber adapter monomer, a spark plug, an air channel and a fuel channel are arranged on the cylinder cover or the ignition chamber adapter monomer, the spark plug is arranged above the ignition chamber, the air channel and the fuel channel are communicated with the ignition chamber, the air supply branch is communicated with the air channel, and the fuel supply branch is communicated with the fuel channel; the ignition chamber is communicated with the main combustion chamber optionally, the air supply branch comprises a pressure accumulation chamber and an air nozzle, and the air nozzle is arranged in the air channel;

an air guide hole is arranged below the jet orifice of the air nozzle,

one end of the air guide hole close to the ignition chamber is of a tapered structure and extends to the ignition chamber from the jet orifice of the air nozzle along the tangential direction of the wall surface of the ignition chamber;

or the air guide hole is an equal-diameter bent pipe channel and faces to the central axis direction of the ignition chamber;

or the air guide hole is an equal-diameter bent pipe channel and is arranged in an obliquely downward direction, and the axis of the air guide hole is intersected with the axis of the fuel spray hole at a position close to the spark plug in the ignition chamber.

Optionally, a one-way relief valve is provided between the pressure accumulation chamber and the air nozzle.

Optionally, the pressure accumulation chamber is in communication with an air pressure pump or an engine block supercharger.

Optionally, the air nozzle is fixed in the air channel by a bolt.

Optionally, the fuel supply branch comprises a fuel tank, a low-pressure fuel pump and a fuel nozzle which are sequentially communicated through a pipeline; the fuel nozzle is disposed within the fuel passage.

Optionally, the fuel nozzle is arranged obliquely, and an injection port of the fuel nozzle faces one side of the air supply branch; the jet orifice of the fuel nozzle is a single-hole or multi-hole or cross jet orifice or outward-opening annular nozzle.

Optionally, the fuel nozzle is bolted into the fuel passage.

Optionally, the air amount and the fuel amount in the ignition chamber, the injection time and the ignition time are accurately controlled respectively; firstly, spraying partial air to sweep the waste gas in the ignition chamber, and secondly, spraying fuel and the residual air to rapidly mix in the ignition chamber; the proportion of fuel and air in the ignition chamber is adjusted according to the operating condition so as to ensure the combustion stability and avoid knocking; the ignition time is determined by the target combustion phase of the main combustion chamber, the composition of mixed gas in the ignition chamber and the flame jet characteristic.

Compared with the prior art, the invention has the following technical effects:

the main structure of the fuel-air separation active control type ignition chamber system comprises an air supply branch and a fuel supply branch which are arranged at the top of the ignition chamber; the pre-combustion air is directly supplied by an air pressure pump or is supplied by a bypass from the downstream of a supercharger of an engine body, and the pressure difference between the downstream of the supercharger and the inside of a cylinder is utilized to realize the ventilation of an ignition chamber in the later stage of an exhaust stroke or the earlier stage of an intake stroke. After being stabilized by the air pressure accumulation chamber, the mixture is supplied to the air nozzle end through the one-way safety valve, active scavenging in the ignition chamber is realized, and the composition of the mixed gas in the ignition chamber can be controlled in real time according to information such as load, fuel air proportion in the main combustion chamber and the like, so that the combustion stability and controllability are improved.

The fuel nozzle is obliquely arranged downwards, and the gasification and the tumble of the fuel are enhanced by utilizing the arc structure and the local high temperature at the lower end of the ignition chamber, so that the distribution of combustible gas around the spark plug is ensured. The air guide hole is an equal-diameter bent pipe channel, faces the direction of the central axis of the ignition chamber and faces the direction of the spark plug obliquely upwards so as to improve the waste gas residue at the upper part of the ignition chamber and near the spark plug and improve the ventilation efficiency. The end of the air guide hole close to the ignition chamber is of a gradually-reduced structure, extends to the ignition chamber from the jet orifice of the air nozzle along the tangential direction of the wall surface of the ignition chamber, and improves the ventilation efficiency in the ignition chamber by enhancing the air inlet speed and the vortex speed. The air guide hole is an equal-diameter bent pipe channel and is arranged in an obliquely downward direction, the axis of the air guide hole is intersected with the axis of the fuel spray hole in the inner space of the ignition chamber, and the cross collision of the air flow beams and the fuel flow beams in the ignition chamber is promoted by optimizing the air injection timing and the fuel injection timing, so that the evaporation and mixing of the fuel are promoted.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a fuel-air separation active control type ignition chamber system of the present invention, which adopts a tapered air guide hole and a tangential air inlet mode along the wall surface of the ignition chamber.

Fig. 2 is a schematic sectional view of the active control type ignition chamber system for fuel-air separation according to the present invention.

Fig. 3 is another structural schematic diagram of the fuel-air separation active control type ignition chamber system of the invention, which adopts a cylindrical air guide hole with equal diameter and an air inlet mode facing to the central axis of the ignition chamber.

Fig. 4 is a schematic cross-sectional structural view of the fuel-air separation actively controlled ignition chamber system of the present invention.

Fig. 5 is another structural diagram of the fuel-air separation active control type ignition chamber system of the invention, which adopts a structure that the axes of the diametrically cylindrical gas guide holes and the fuel spray hole axes intersect in the internal space of the ignition chamber.

FIG. 6 is a fuel nozzle orifice configuration that may be employed with the fuel air separation actively controlled ignition chamber system of the present invention;

FIG. 6(1) is a single orifice (or independent multi-orifice) fuel nozzle;

FIG. 6(2) is a multi-hole external cross-jet fuel nozzle;

FIG. 6(3) is a multi-hole internal cross-jet fuel nozzle;

FIG. 6(4) shows an outward opening annular fuel nozzle.

Description of reference numerals: 1. air pressure pumps or engine block superchargers; 2. a pressure accumulation chamber; 3. a one-way safety valve; 4. an air nozzle; 5. a spark plug; 6. a cylinder head or ignition chamber adapter unit; 7. a fuel tank; 8. a low-pressure fuel pump; 9. a fuel nozzle; 10. an ignition chamber body.

Fig. 7 is a timing chart of ignition chamber ventilation, fuel injection, ignition process when the fuel-air separation active control type ignition chamber system of the present invention is applied to an internal combustion engine, and influence factors of corresponding control parameters.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in fig. 2, the present embodiment provides a fuel-air separation active control ignition chamber system, which includes an air supply branch and a fuel supply branch disposed at the top of the ignition chamber; the ignition chamber is arranged on a cylinder cover or an ignition chamber adapter monomer 6, a spark plug 5, an air channel and a fuel channel are arranged on the cylinder cover or the ignition chamber adapter monomer, the spark plug 5 is arranged above the ignition chamber, the air channel and the fuel channel are communicated with the ignition chamber, an air supply branch is communicated with the air channel, and a fuel supply branch is communicated with the fuel channel.

The air supply branch comprises a pressure accumulation chamber 2 and an air nozzle 4, and the air nozzle 4 is arranged in the air channel. A one-way relief valve 3 is provided between the pressure accumulation chamber 2 and the air nozzle 4. The pressure accumulation chamber 2 communicates with an air pressure pump or an engine block supercharger 1. As shown in fig. 2, a gas guide hole is arranged below the injection port of the air nozzle 4, the gas guide hole extends from the injection port of the air nozzle 4 to the ignition chamber along a tangential direction, and one end of the gas guide hole close to the ignition chamber is of a tapered structure, so that the air exchange efficiency in the ignition chamber is improved by enhancing the air inlet speed and the vortex speed. As shown in fig. 4, the air vent is an equal diameter elbow passage, and faces the central axis of the ignition chamber 10 and obliquely upward to the direction of the spark plug 5, so as to improve the exhaust gas residue at the upper part of the ignition chamber and near the spark plug and improve the ventilation efficiency. As shown in fig. 5, the gas guide holes are equal-diameter elbow passages and are arranged in an obliquely downward direction, the axes of the gas guide holes and the axes of the fuel spray holes 9 intersect in the internal space of the ignition chamber, and the cross collision of the air flow streams and the fuel flow streams in the ignition chamber 10 is promoted by optimizing the air injection timing and the fuel injection timing, so that the fuel evaporation and mixing are promoted. The air nozzle 4 is fixed in the air passage by bolts.

The fuel supply branch comprises a fuel tank 7, a fuel low-pressure pump 8 and a fuel nozzle 9 which are communicated in sequence by pipelines; the fuel nozzle 9 is disposed in the fuel passage. The fuel nozzle is obliquely arranged, and the jet orifice of the fuel nozzle faces one side of the air supply branch. Cross-orifice fuel nozzles, or outwardly opening annular fuel nozzles, may be employed to promote multiple fuel beam impingement and mixing within the narrow firing chamber. The fuel nozzle 9 is fixed in the fuel passage by bolts. The fuel gasification and the tumble are enhanced by utilizing the arc structure and the local high temperature at the lower end of the ignition chamber, and the distribution of combustible gas around the spark plug 5 is ensured. The scavenging efficiency of the ignition chamber and the forming efficiency of the mixed gas are improved through structural optimization.

The air quantity and the fuel quantity are accurately controlled according to different working conditions, the air and the fuel quantity are mixed in the ignition chamber, high ignition probability is realized through equivalence ratio optimization, and the proportion of fuel and air in the ignition chamber is adjusted according to the operation working conditions and the composition of mixed gas in the main combustion chamber. Specifically, under the conditions of low load, rarer main combustion chamber mixed gas or large proportion exhaust gas recirculation quantity, a richer ignition chamber fuel-air proportion is adopted to enhance the flame jet energy of the ignition chamber and ensure the combustion stability. Under the condition of high load and richer main combustion chamber mixed gas, the leaner ignition chamber fuel-air ratio is adopted to avoid the knocking tendency.

The pre-combustion air is directly supplied by an air pressure pump or is supplied by a bypass from the downstream of a supercharger of an engine body, and the pressure difference between the downstream of the supercharger and the inside of a cylinder is utilized to realize the ventilation of an ignition chamber in the later stage of an exhaust stroke or the earlier stage of an intake stroke. The pressure of the air pressure accumulation chamber 2 is stabilized and then the air is supplied to the end of the air nozzle 4 through the one-way safety valve 3.

The fuel in the ignition chamber is not particularly limited, and may be the same as the fuel in the main combustion chamber, or may be a specific liquid or gaseous fuel for ignition.

Immediately after the engine is started, the fuel low-pressure pump 8 and the air pressure pump or a bypass opened downstream of the engine body supercharger 1 are opened, and the fuel injection pressure and the pressure of the air pressure accumulation chamber 2 are rapidly built up.

And in the later period of the exhaust stroke or the early period of the intake stroke, the valve of the air nozzle 4 is opened, and high-pressure air is sprayed into the ignition chamber and extrudes residual waste gas out of the ignition chamber to realize active scavenging because the pressure of the air pressure accumulation chamber 2 is greater than the pressure of the main combustion chamber. The opening time of the air nozzle 4 is determined according to the target air-fuel mixture ratio of the ignition chamber and the air pressure difference.

In the latter part of the intake stroke or in the early part of the compression stroke, the valve of the fuel nozzle 9 is opened, and fuel is injected into the ignition chamber to rapidly form a combustible mixture with the previously injected air. The opening time of the fuel injection nozzle 9 is determined according to the target air-fuel mixture ratio of the ignition chamber and the fuel injection pressure.

At a predetermined timing in the latter stage of the compression stroke, the ignition plug 5 is ignited to ignite the premixed gas in the ignition chamber, and thereafter the generated flame jet or high temperature combustion product jet enters the main combustion chamber through the lower end orifice of the ignition chamber body 10 to ignite the lean premixed gas in the main combustion chamber. The ignition timing of the spark plug 5 is determined by the target combustion phase of the lean premixed gas in the main combustion chamber, the composition of the premixed gas in the ignition chamber, the flame jet characteristic and the like.

Through ignition chamber structure optimization and air-fuel separation supply control, active scavenging and ignition chamber mixed gas equivalence ratio optimization are realized, and high ignition probability and stable combustion under the conditions of lean premixed combustion and large-proportion exhaust gas recirculation are realized.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein, and any reference signs in the claims are not intended to be construed as limiting the claim concerned.

The principle and the implementation mode of the present invention are explained by applying specific examples in the present specification, and the above descriptions of the examples are only used to help understanding the method and the core idea of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.