CN112112725A - Combustion chamber system suitable for high-power-density diesel engine - Google Patents
Combustion chamber system suitable for high-power-density diesel engine Download PDFInfo
- Publication number
- CN112112725A CN112112725A CN202011044900.8A CN202011044900A CN112112725A CN 112112725 A CN112112725 A CN 112112725A CN 202011044900 A CN202011044900 A CN 202011044900A CN 112112725 A CN112112725 A CN 112112725A
- Authority
- CN
- China
- Prior art keywords
- combustion chamber
- oil
- main
- auxiliary
- fuel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B23/00—Other engines characterised by special shape or construction of combustion chambers to improve operation
- F02B23/02—Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition
- F02B23/06—Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition the combustion space being arranged in working piston
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B23/00—Other engines characterised by special shape or construction of combustion chambers to improve operation
- F02B23/02—Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B23/00—Other engines characterised by special shape or construction of combustion chambers to improve operation
- F02B23/02—Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition
- F02B23/06—Other engines characterised by special shape or construction of combustion chambers to improve operation with compression ignition the combustion space being arranged in working piston
- F02B23/0645—Details related to the fuel injector or the fuel spray
- F02B23/0669—Details related to the fuel injector or the fuel spray having multiple fuel spray jets per injector nozzle
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F1/00—Cylinders; Cylinder heads
- F02F1/24—Cylinder heads
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
- F02M29/00—Apparatus for re-atomising condensed fuel or homogenising fuel-air mixture
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/12—Improving ICE efficiencies
Abstract
The invention belongs to the technical field of diesel engine correlation, and discloses a combustion chamber system suitable for a high-power-density diesel engine. This combustion chamber system is including setting up main combustion chamber and vice combustion chamber, wherein: the fuel oil mist beam of the fuel injector in the main combustion chamber points to the bulge of the combustion chamber, collides with the bulge and is divided into two streams of upward and downward plumes, so that the tendency of forming fire packet oil in the later combustion period is weakened; high-temperature and high-pressure gas combusted in the auxiliary combustion chamber is ejected out through the throat, the high-temperature and high-pressure gas comprises a horizontal component and a vertical component, the horizontal component disturbs the ejection direction of oil mist bundles in the main combustion chamber, the phenomenon of oil-in-fire in the early stage of combustion is broken, and the vertical component pushes the piston to do work downwards; the air entering the auxiliary combustion chamber through the throat forms a rotational flow in the auxiliary combustion chamber, promotes the complete combustion of the fuel in the auxiliary combustion chamber, and improves the effect of simulating the phenomenon of oil-in-fire. The invention solves the phenomenon of oil-in-fire in the high-lift diesel engine, improves the combustion efficiency of the internal combustion engine and has strong practicability.
Description
Technical Field
The invention belongs to the technical field of diesel engines, and particularly relates to a combustion chamber system suitable for a high-power-density diesel engine.
Background
The combustion process of an internal combustion engine can be summarized as the following steps: the air inlet valve is opened, and the piston moves downwards to suck air; the air inlet valve is closed, and the piston moves upwards to compress air to form a high-temperature and high-pressure environment; near the top dead center of the piston, fuel oil is sprayed into a combustion chamber, local combustible mixed gas is formed through atomization, evaporation, mixing and the like, and then the local combustible mixed gas is naturally ignited in a high-temperature high-pressure environment; the fuel oil is burnt to release heat, and the gas expands rapidly to push the piston to move downwards and do work outwards; the exhaust valve then opens and the piston travels upward to expel the combusted exhaust, thereby completing a work cycle. As can be seen from the above, the combustion process of the diesel engine involves the matching of oil-gas-chambers, and specifically, the combustion system of the internal combustion engine is composed of an oil injection system, an air intake and exhaust system, a combustion chamber system, and the like.
Under the scenes with higher power-per-liter requirements, such as special power devices, high-power-per-liter military vehicle power and military ship power, the working temperature and working pressure in a combustion chamber system are far higher than the working conditions of a conventional diesel engine, and the excessively high working temperature causes the stagnation period of diesel injection ignition to be greatly shortened. Diesel oil is sprayed into a cylinder and quickly catches fire in an overhigh working temperature environment, the proportion of combustible mixed gas formed by mixing in the early combustion lag period is greatly reduced, so that the combustion of the whole diesel oil spray basically belongs to diffusion combustion, the amount of air sucked into the spray is greatly reduced due to the early diffusion combustion, cap-shaped flame is formed around a fuel oil spray beam after the combustion, the cap-shaped flame can further isolate the entrainment and mixing of the fuel oil and the air, and the phenomenon of oil covering is caused. Under the condition, the spraying oil-gas mixing progress is greatly reduced, the combustion speed is greatly reduced, the afterburning of the diesel engine is serious, the fuel oil is insufficiently combusted, the highest combustion pressure is obviously reduced, the work capacity of the engine is reduced, the heat load is greatly improved, and finally the dynamic property, the economical efficiency and the reliability of the whole engine are seriously deteriorated.
The key point for solving the problems is to enhance the mixing efficiency of fuel oil and air and break or relieve the formation of the phenomenon of oil-in-fire. From the fuel level, ethanol and water can be mixed into diesel oil, and the high latent heat of vaporization of the ethanol and the water is utilized to reduce the local temperature and prolong the combustion lag period. In addition, the high volatility of ethanol and water produces the microexplosion, strengthens the atomizing evaporation of diesel oil for the mixing efficiency of fuel oil and air obtains promoting. However, the calorific value of ethanol and water is low, the mode of reducing local temperature by using the latent heat of vaporization of the ethanol and the water is not beneficial to improving the power per liter of the diesel engine, and the power performance of the diesel engine can be seriously influenced by mixing more ethanol and water. In addition, the mixed fuel has storage instability, for example, the mixed ethanol diesel oil can generate a layering phenomenon after being stored for a long time, which brings hidden troubles to the smooth operation of special power plants. From the angle of flow, optimize the structural design of combustion chamber, adopt the combustion chamber structure of special form, for example two swirl combustion chambers, through the collision of spraying and combustion chamber boss, split the spraying end, can strengthen the mixture of burning later stage fuel and air to break "the fire and wrap oil" phenomenon in the later stage of burning. In addition, the double-swirl combustion chamber structure needs to utilize spray flame to impact the wall surface of the piston, complete flame oil to impact the boss of the combustion chamber and complete combustion of most fuel oil near the boss of the combustion chamber, so that the working temperature of the piston can be further improved, the reliability of an engine is influenced, the working temperature of the combustion chamber is further improved, the flame oil to be coated is easier to appear, and the problem of flame oil to be coated cannot be well solved by only adopting the double-swirl combustion chamber.
In summary, aiming at the phenomenon of oil in a fire bag existing in high-lift diesel engines such as special power devices and the like, the existing combustion chamber technology is difficult to completely solve, and research and design are urgently needed in the field to obtain a technology for remarkably improving the phenomenon of oil in a fire bag, so that the overall performance of the high-lift diesel engines such as the special power devices and the like is improved.
Disclosure of Invention
Aiming at the defects or improvement requirements in the prior art, the invention provides the combustion chamber system suitable for the high-power density diesel engine, and the phenomenon of oil-in-fire from the early combustion stage to the later combustion stage in the high-power density diesel engine is effectively solved through the integral structural design of the main combustion chamber and the auxiliary combustion chamber and the design of the throat in the auxiliary combustion chamber, so that the overall performance of the internal combustion engine is improved, and the combustion chamber system has strong practicability.
To achieve the above object, according to the present invention, there is provided a combustion chamber system suitable for a high power density diesel engine, the combustion chamber system comprising a primary combustion chamber provided in a piston and a secondary combustion chamber provided in a cylinder head, wherein:
the main oil sprayer is arranged in the main combustion chamber, a plurality of oil spray holes are formed in a nozzle of the main oil sprayer along the circumferential direction, an inward bulge is formed in the middle of the circumferential side wall of the main combustion chamber, a fuel oil mist beam sprayed out of the oil spray holes points to the bulge, the tail end of the sprayed fuel oil mist beam collides with the bulge and is divided into two upward and downward swirling flows, the upward and downward swirling flows are further mixed with air in the main combustion chamber, the mixing effect of fuel oil and air is enhanced, and the tendency of forming fire-coated oil in the main combustion chamber in the later combustion period is weakened;
the auxiliary combustion chamber is arranged obliquely above the main combustion chamber, an auxiliary fuel injector is arranged above the auxiliary combustion chamber along the direction of a central axis, the auxiliary combustion chamber is connected with the main combustion chamber through an air inlet rubbing hole, the upper end of the air inlet rubbing hole is provided with a throat connected with the auxiliary combustion chamber, the sectional area of the throat is smaller than that of the air inlet rubbing hole, so that high-temperature and high-pressure gas sprayed out of the auxiliary combustion chamber forms high-speed jet flow, in addition, the axial direction of the throat is not vertical to the horizontal direction, so that the high-speed jet flow sprayed out of the auxiliary combustion chamber comprises two components of a vertical component and a horizontal component, the vertical component is used for pushing the piston to move downwards, the horizontal component is used for making tangential rotational flow movement along the inner wall of the main combustion chamber, fuel spray beams sprayed out of the main fuel injector in the main combustion chamber are disturbed, and the mixing of fuel and air is, thereby breaking the phenomenon of oil-in-fire in the early combustion stage in the main combustion chamber.
Further preferably, the central axis of the throat is not coincident with the central axis of the auxiliary fuel injector, air entering the auxiliary combustion chamber through the throat interacts with the wall surface of the auxiliary combustion chamber, and under the guidance of the wall surface of the auxiliary combustion chamber, tangential rotational flow is formed in the auxiliary combustion chamber to accelerate the mixing of fuel oil and air, so that the fuel oil in the auxiliary combustion chamber is fully combusted, the disturbance efficiency of high-temperature and high-pressure gas sprayed out from the throat of the auxiliary combustion chamber on the spray oil bundles of the main fuel injector is enhanced, and the inhibition effect of the auxiliary combustion chamber on the formation of the oil-in-fire phenomenon in the main combustion chamber is enhanced.
Further preferably, the oil injection holes on the main oil injector are provided with a plurality of layers of injection holes, and the oil injection holes on each layer are distributed in a staggered manner, so that the injected fuel oil can be fully contacted and mixed with air, and the combustion efficiency is improved.
Further preferably, the auxiliary combustion chamber and the throat are externally provided with cooling cavities, so that on one hand, the phenomenon that the auxiliary combustion chamber and the throat are damaged due to overlarge local thermal stress is avoided, and on the other hand, the phenomenon that the temperature and the pressure in the auxiliary combustion chamber are too high to prolong the stagnation period is avoided, so that oil-gas mixing and fuel oil full combustion in the auxiliary combustion chamber are not facilitated.
Further preferably, the oil injection phase of the secondary oil injector is earlier than the phase of the main oil injector, that is, the secondary oil injector injects oil before the main oil injector, so that the tangential rotational flow formed by the high-speed airflow ejected from the secondary combustion chamber in the main combustion chamber can be ensured to fully act with the oil beam ejected by the main oil injector, and the phenomenon that the main combustion chamber forms oil in a fire bag at the early stage of combustion is avoided.
Further preferably, the diameter of the bottom surface of the air inlet expanded hole, which is close to the main combustion chamber, is larger than the diameter of the top surface of one end of the air inlet expanded hole, which is connected with the throat opening, so that air can be conveniently compressed in the main combustion chamber to enter the auxiliary combustion chamber, and meanwhile, the problem that the length of the throat opening is too long to cause the loss of the throttle is avoided.
Generally, compared with the prior art, the technical scheme of the invention has the following beneficial effects:
1. the combustion system comprises a main combustion chamber and an auxiliary combustion chamber, wherein the added auxiliary combustion chamber generates high-speed jet flow through a throat opening which is specially designed under the condition of not changing the structure of a primary air valve system, the high-speed jet flow does tangential rotational flow motion along the inner wall of the main combustion chamber on one hand, and disturbs fuel oil spray mist beams in the main combustion chamber, so that the fuel oil and air are mixed more fully, the phenomenon of 'oil in fire' in the early stage of combustion is effectively inhibited or broken, the combustion rate is improved, the after-combustion phenomenon is reduced, the full combustion of the fuel oil gas in the main combustion chamber is promoted, meanwhile, the heat load of the combustion chamber is reduced, and on the other hand, a piston is pushed to move downwards to provide power;
2. according to the invention, the bulge is arranged in the middle of the circumferential side wall of the main combustion chamber, so that the fuel oil mist sprayed from the main oil sprayer can impact the bulge structure, the tail end of the fuel oil mist is divided into two parts to form double swirl flow, the two swirl flow are further mixed with the air in the main combustion chamber, the mixing effect of fuel oil and air is effectively promoted, and the tendency of forming fire-coated oil in the later combustion stage is weakened;
3. the main oil sprayer is provided with a plurality of layers of small oil injection holes, the volume of each fuel oil mist bundle can be reduced due to the increased number of the injection holes, the surface-to-volume ratio of each fuel oil mist bundle is increased, so that the injected fuel oil can be fully contacted and mixed with air, the combustion efficiency is improved, and the possibility of generating ladle oil in the whole combustion process is weakened; meanwhile, the oil spray holes of each layer are distributed in a staggered mode, and the multi-direction arrangement caused by the multi-hole fog beams also improves the air utilization rate in the main combustion chamber, so that the oil-gas mixing efficiency is improved, and the strength of the oil-in-fire phenomenon is further weakened;
4. in the invention, the cooling cavities are arranged at the peripheries of the auxiliary combustion chamber and the throat opening, so that on one hand, the damage to the auxiliary combustion chamber and the throat opening due to overlarge local thermal stress is avoided, and on the other hand, the over-high temperature and pressure in the auxiliary combustion chamber are avoided, which is not beneficial to prolonging the combustion lag period, and is not beneficial to oil-gas mixing and full combustion of fuel oil in the auxiliary combustion chamber;
5. according to the invention, the auxiliary combustion chamber is set to generate tangential rotational flow in the main combustion chamber, and the rotational flow collides with the spray of the main oil injector, so that the phenomenon of oil-in-fire is inhibited in the early stage of combustion; then, a boss is arranged in the main combustion chamber to generate double swirl, and the phenomenon of oil-in-fire is inhibited in the later combustion period; through the arrangement of the plurality of layers of small spray holes, the possibility of producing the flame oil can be weakened in the whole combustion process, and the flame oil phenomenon generated in the high-power-density diesel engine can be finally solved.
Drawings
FIG. 1 is a schematic block diagram of a combustion chamber system for a high power density diesel engine constructed in accordance with a preferred embodiment of the present invention;
FIG. 2 is a top view of a primary oil jet constructed in accordance with a preferred embodiment of the present invention;
fig. 3 is a schematic view of a double row oil jet structure of a main oil injector constructed according to a preferred embodiment of the present invention.
The same reference numbers will be used throughout the drawings to refer to the same or like elements or structures, wherein:
1-cylinder cover, 2-main oil sprayer, 3-main oil sprayer nozzle, 4-cooling cavity, 5-auxiliary oil sprayer, 6-auxiliary combustion chamber, 7-throat, 8-upper pit, 9-bulge, 10-upper oil beam, 11-lower pit, 12-main combustion chamber, 13-piston, 14-lower oil beam, 15-upper oil spray hole, 16-lower oil spray hole and 17-air inlet expanding hole.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
The embodiment of the invention provides a main-auxiliary double-combustion chamber system for a high-power-density diesel engine, wherein for a main combustion chamber, the phenomenon of oil-in-fire in the main combustion chamber is inhibited by adopting the following modes: 1) the high-temperature and high-pressure gas generated by advanced oil injection and combustion of the auxiliary combustion chamber in the double-combustion-chamber system is sprayed out from the throat to form high-speed jet flow, so that a tangential rotational flow in the horizontal direction is formed in the main combustion chamber, the rotational flow can collide with fuel oil spray of the main oil sprayer, disturbance of the fuel oil spray is promoted, mixing of the fuel oil and air is accelerated, and the phenomenon of oil-in-fire in the main combustion chamber at the early stage of combustion is inhibited and broken; the other part of the component is vertical to the piston to push the piston downwards and is matched with the main combustion chamber to do work on the piston; 2) the structure of a main combustion chamber on the piston is optimized, and the special combustion chamber structure, such as bulges distributed on the circumference in the combustion chamber, is utilized to form splitting on the tail end of fuel spray, so that a double-swirl effect is formed, the mixing of fuel and air is further promoted, and the phenomenon of oil wrapped in fire in the main combustion chamber is further broken at the middle and later stages of combustion; 3) the main oil sprayer is provided with a main oil sprayer with a plurality of layers of small oil spray holes, the volume of each fuel oil spray beam is reduced by increasing the number of the oil spray beams, the surface-to-volume ratio of the spray beams is increased, the air utilization rate in the main combustion chamber is enhanced, better mixing of oil and gas is promoted, and the strength of the phenomenon of oil-in-fire is further weakened; for the auxiliary combustion chamber, the central axis of the throat is not coincident with the central axis of the auxiliary fuel injector, so that air entering the auxiliary combustion chamber through the throat is acted with the wall surface of the auxiliary combustion chamber, a guiding rotational flow is formed in the auxiliary combustion chamber, the mixing of fuel and air is accelerated, the fuel in the auxiliary combustion chamber is fully combusted, the disturbance efficiency of high-temperature and high-pressure gas sprayed out from the throat of the auxiliary combustion chamber on the spray oil beam of the main fuel injector is enhanced, and the inhibition effect of the auxiliary combustion chamber on the formation of the oil-in-fire phenomenon in the main combustion chamber is enhanced.
The invention is further illustrated by the following specific examples.
As shown in fig. 1, in the present embodiment, the dual combustion chamber system includes a main combustion chamber disposed in a piston and an auxiliary combustion chamber disposed in a cylinder head, which specifically includes a cylinder head 1, a main injector 2, a main injector nozzle 3, a cooling cavity 4, an auxiliary injector 5, an auxiliary combustion chamber 6, a throat 7, an upper pit 8, a protrusion 9, a lower pit 11, a main combustion chamber 12, a piston 13, an upper oil injection hole 15, and a lower oil injection hole 16.
The auxiliary fuel injector 5 is arranged in an auxiliary combustion chamber 6, and the auxiliary fuel injector and the auxiliary combustion chamber are arranged on the cylinder cover 1 together; the main oil injector 2 is arranged on the cylinder head 1, and the main combustion chamber 12 is positioned between the cylinder head 1 and the piston 13; the auxiliary combustion chamber 6 is communicated with the main combustion chamber 12 by means of a throat 7.
Specifically, the auxiliary combustion chamber 6 is arranged obliquely above the main combustion chamber 12, an auxiliary fuel injector 5 is arranged above the auxiliary combustion chamber 6 along the direction of a central axis, the auxiliary combustion chamber 6 is connected with the main combustion chamber 12 through an air inlet rubbing hole 17, a throat connected with the auxiliary combustion chamber 6 is arranged at the upper end of the air inlet rubbing hole 17, the sectional area of the throat is smaller than the sectional area of the air inlet rubbing hole 17, and the inclination direction of the throat is matched with the main combustion chamber 12, so that high-temperature high-pressure gas sprayed out of the auxiliary combustion chamber 6 is in a high-speed state on one hand, high-speed gas sprayed out of the auxiliary combustion chamber 6 comprises a horizontal component and a vertical component on the other hand, the horizontal component makes tangential rotational flow motion along the inner wall of the main combustion chamber 12, and is used for disturbing fuel fog sprayed out of a main fuel injector in the main combustion chamber 12, accelerating the mixing of fuel and air, and further breaking the phenomenon of oil, the vertical component pushes the piston to move downwards, so that the working capacity of the fuel gas is improved;
in addition, the central axis of the throat is not coincident with the central axis of the auxiliary fuel injector 5, air entering the auxiliary combustion chamber 6 through the throat is acted on the wall surface of the auxiliary combustion chamber 6, under the guidance of the wall surface of the auxiliary combustion chamber 6, tangential rotational flow is formed in the auxiliary combustion chamber 6, the mixing of fuel and air in the auxiliary combustion chamber 6 is accelerated, the sufficient combustion of the fuel in the auxiliary combustion chamber 6 is promoted, the disturbance efficiency of high-temperature and high-pressure gas sprayed out of the auxiliary combustion chamber 6 through the throat to the spraying of the main fuel injector can be enhanced, the inhibition effect of the auxiliary combustion chamber 6 on the formation of the oil-in-fire phenomenon in the main combustion chamber 12 is enhanced, and the oil-in-fire phenomenon in the early combustion period is avoided.
Furthermore, a main oil sprayer is arranged in the main combustion chamber 12, a plurality of oil spray holes are formed in a nozzle of the main oil sprayer in the circumferential direction, an inward protrusion 9 is arranged in the middle of the circumferential side wall of the main combustion chamber 12, a fuel oil mist beam sprayed out of each oil spray hole points to the protrusion 9, the tail end of the sprayed fuel oil mist beam collides with the protrusion 9 and is divided into two streams of upward and downward swirling flows, the two swirling flows are further mixed with air in the main combustion chamber 12, the mixing effect of fuel oil and air is strengthened, and the tendency of forming ladle oil in the later combustion period is weakened.
Further, the fuel mist jet from the main fuel injector 2 is directed toward a protrusion 9 provided in the main combustion chamber. As shown in fig. 2, the upper layer oil beam 10 formed by the upper layer oil injection hole 15 of the main oil injector 3 and the lower layer oil beam 14 formed by the lower layer oil injection hole 16 are offset by a certain angle in the circumferential direction and are distributed in a staggered way in space; as shown in fig. 3, in this embodiment, two layers of small oil injection holes are provided on the main oil injector 2, which also improves the air utilization rate in the main combustion chamber, so as to improve the mixing efficiency of oil and gas, further weaken the intensity of the fire-coated oil phenomenon, reduce the volume of each fuel oil mist bundle by increasing the number of injection holes, and increase the surface-to-volume ratio of the mist bundles, so that the injected fuel oil can be fully contacted and mixed with the air, so as to enhance the atomization and mixing capability of the oil bundles, improve the combustion efficiency, weaken the possibility of the fire-coated oil, and simultaneously, each layer of spray is distributed in a staggered manner, resulting in multi-directional arrangement of the mist bundles, significantly improving the air utilization rate in the main combustion chamber, so as to improve the mixing efficiency of oil and gas, further weaken the possibility of the fire-coated oil phenomenon, and finally, a double swirl bulge 9 is provided in the main combustion chamber on the piston, so that the development direction of the oil bundles all point to the bulge 9 between the upper pit, therefore, the tail end of the oil bundle is split under the action of the molded line of the combustion chamber to form downward and upward swirl at the same time, and the swirl is further mixed with air in the main combustion chamber, so that the mixing of fuel oil and air is enhanced, and the tendency of forming ladle oil in the later combustion period is weakened in the middle and later combustion periods.
Furthermore, the cooling cavity is arranged outside the auxiliary combustion chamber 6 and at the periphery of the throat, so that ultrahigh temperature and high pressure close to the main combustion chamber 12 are prevented from being formed in the auxiliary combustion chamber 6, the stagnation period in the auxiliary combustion chamber 6 can be effectively prolonged, the sufficient mixing of oil and gas is facilitated, the complete combustion of fuel oil in the auxiliary combustion chamber 6 is promoted, and the inhibition effect of the auxiliary combustion chamber 6 on the oil-in-fire phenomenon of the main combustion chamber 12 is enhanced. Meanwhile, the cooling cavity is arranged at the periphery of the throat, so that overlarge local thermal stress at the throat can be avoided, and the reliability of the engine is improved.
Further, the main oil injector 2 and the auxiliary oil injector 3 are independently adjusted, parameters such as injection pressure, phase, pulse width and the like are flexibly adjusted, the oil injection phase of the auxiliary oil injector is earlier than the oil injector phase of the main oil injector, the auxiliary oil injector 5 firstly injects a proper amount of fuel oil into the auxiliary combustion chamber 6, the fuel oil is sufficiently atomized, mixed and combusted in the auxiliary combustion chamber 6, high-temperature and high-pressure gas is generated in the auxiliary combustion chamber 6, and then high-speed jet flow is formed through the throat 7 and is injected into the main combustion chamber 12, as shown in fig. 2, the throat 7 enables the high-speed jet flow to generate a component along the circumferential direction of the main combustion chamber 12, so that strong tangential rotational flow is formed in the main. Near the moment when the high-temperature gas in the auxiliary combustion chamber is sprayed out through the throat opening 7, the main oil sprayer 2 is opened, the fuel oil is sprayed into the main combustion chamber 12, the spray sprayed by the main oil sprayer 2 collides with the high-temperature gas sprayed out from the auxiliary combustion chamber 6, the atomization of oil bundles and the oil-gas mixing are promoted in the early stage of spray ignition of the main oil sprayer, and the oil-in-fire phenomenon in the early stage of spray combustion is inhibited and broken.
Further, the diameter of the bottom surface of the air inlet expanding hole 17, which is close to the main combustion chamber 12, is larger than the diameter of the top surface of one end connected with the throat, so that air is compressed by the main combustion chamber 12 to enter the auxiliary combustion chamber 6, and meanwhile, the length of the throat is prevented from being too long, and the throttle loss is caused.
The operation of the combustion system is described below in connection with an embodiment of the invention.
Firstly, in fig. 1, the piston 13 moves upwards to compress the air sucked in the previous process, so that the temperature and the pressure of the main combustion chamber 12 and the auxiliary combustion chamber 6 are increased sharply, and the temperature of the auxiliary combustion chamber 6 is lower than that of the main combustion chamber 12 due to the fact that the cylinder head 1 is provided with the cooling cavity 4;
then, an auxiliary fuel injector 5 of the auxiliary combustion chamber starts to inject fuel, gas and fuel in the auxiliary combustion chamber are mixed and start to burn, and high-speed jet flow is generated after the combustion and enters the main combustion chamber;
next, the main oil sprayer 2 in the main combustion chamber starts oil injection, the gas and the fuel oil in the main combustion chamber start combustion, the high-speed jet flow entering from the throat 7 disturbs the fuel oil spray in the main combustion chamber in the early stage of combustion to promote the mixing of the fuel oil and the gas, when the fuel oil spray reaches the middle part of the side wall of the main combustion chamber, the bulge of the side wall collides with the fuel oil spray to form double swirl flow, the fuel oil spray in the later stage of combustion is disturbed, and the mixing of the fuel oil and the gas is further promoted;
meanwhile, under the action of the high-speed jet flow of the auxiliary combustion chamber, the piston 13 slowly descends.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (6)
1. A combustion chamber system suitable for high power density diesel engines, characterized in that it comprises a primary combustion chamber (12) arranged in a piston (13) and a secondary combustion chamber (6) arranged in a cylinder head (1), wherein:
a main oil sprayer (2) is arranged in the main combustion chamber (12), a plurality of oil spray holes are formed in a nozzle of the main oil sprayer along the circumferential direction, an inward protrusion (9) is arranged in the middle of the circumferential side wall of the main combustion chamber, a fuel oil fog beam sprayed out of the oil spray holes points to the protrusion, the tail end of the sprayed fuel oil fog beam collides with the protrusion and is divided into an upward swirl and a downward swirl, the upward swirl and the downward swirl are further mixed with air in the main combustion chamber, the mixing effect of fuel oil and air is strengthened, and the tendency of forming fire pack oil in the main combustion chamber in the later combustion period is weakened;
the auxiliary combustion chamber (6) is arranged obliquely above the main combustion chamber (12), an auxiliary fuel injector (9) is arranged above the auxiliary combustion chamber along the direction of a central axis, the auxiliary combustion chamber is connected with the main combustion chamber through an air inlet expanding hole (17), a throat (7) connected with the auxiliary combustion chamber is arranged at the upper end of the air inlet expanding hole (17), the sectional area of the throat is smaller than that of the air inlet expanding hole (17), so that the gas sprayed out of the auxiliary combustion chamber forms high-speed jet flow, in addition, the axial direction of the throat is not vertical to the horizontal direction, so that the high-speed jet flow sprayed out of the auxiliary combustion chamber comprises two components of a vertical component and a horizontal component, the vertical component is used for pushing the piston to move downwards, the horizontal component is used for disturbing the direction of the fuel oil fog beam in the main combustion chamber, the mixing of fuel oil and air is accelerated, and the phenomenon of oil-in-fire in the main combustion chamber is broken.
2. The combustion chamber system suitable for the high-power-density diesel engine is characterized in that the central axis of the throat (7) is not coincident with the central axis of the auxiliary fuel injector (5), air entering the auxiliary combustion chamber through the throat interacts with the wall surface of the auxiliary combustion chamber to form tangential airflow in the auxiliary combustion chamber, so that the mixing of the fuel and the air is accelerated, the fuel in the auxiliary combustion chamber is fully combusted, and the efficiency of oil-in-fire phenomenon in the planned main combustion chamber is enhanced.
3. The combustion chamber system of the diesel engine with high power density as set forth in claim 1, characterized in that the oil injection holes of the main oil injector (2) are provided with a plurality of layers of injection holes, and the oil injection holes of each layer are distributed in a staggered manner, so that the injected fuel can be fully contacted and mixed with air, and the combustion efficiency is improved.
4. The combustion chamber system of claim 1, wherein the auxiliary combustion chamber and the throat are externally provided with cooling cavities, so as to prevent local thermal stress from being too large and damaging the auxiliary combustion chamber and the throat, and prevent temperature and pressure in the auxiliary combustion chamber from being too high and unfavorable for prolonging the stagnation period, thereby unfavorable for oil-gas mixing and sufficient combustion of fuel in the auxiliary combustion chamber.
5. A combustion chamber system adapted for high power density diesel engine according to claim 1, characterized in that the phase of the secondary fuel injector (5) is earlier than the phase of the main fuel injector (2), i.e. the secondary fuel injector injects fuel before the main fuel injector, ensuring that the high speed gas flow emitted from the secondary combustion chamber can sufficiently react with the oil beam sprayed from the main fuel injector in the main combustion chamber, avoiding the formation of fire-coated oil in the early combustion period of the main combustion chamber.
6. The combustion chamber system of claim 1, wherein the diameter of the bottom surface of the inlet manifold (17) near the primary combustion chamber is larger than the diameter of the top surface of the end connected to the throat, thereby facilitating the compression of air from the primary combustion chamber into the secondary combustion chamber while avoiding the loss of throttle due to the excessive length of the throat.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011044900.8A CN112112725A (en) | 2020-09-28 | 2020-09-28 | Combustion chamber system suitable for high-power-density diesel engine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011044900.8A CN112112725A (en) | 2020-09-28 | 2020-09-28 | Combustion chamber system suitable for high-power-density diesel engine |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112112725A true CN112112725A (en) | 2020-12-22 |
Family
ID=73798690
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011044900.8A Pending CN112112725A (en) | 2020-09-28 | 2020-09-28 | Combustion chamber system suitable for high-power-density diesel engine |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112112725A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112780463A (en) * | 2021-03-04 | 2021-05-11 | 哈尔滨工程大学 | Dual-fuel engine adopting dual-gas spray pipe and step spray hole oil sprayer and combustion organization method thereof |
| CN112879149A (en) * | 2021-01-25 | 2021-06-01 | 华中科技大学 | Asymmetric combustion chamber system suitable for high power density diesel engine |
| CN112879148A (en) * | 2021-01-25 | 2021-06-01 | 华中科技大学 | Asymmetric combustion chamber system suitable for high power density diesel engine |
| CN114893289A (en) * | 2022-06-09 | 2022-08-12 | 北京理工大学 | Dredging type supercritical combustion system for diesel engine |
| CN115822803A (en) * | 2023-01-06 | 2023-03-21 | 潍柴动力股份有限公司 | Piston and engine |
Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1470758A (en) * | 2003-06-26 | 2004-01-28 | 上海交通大学 | Dimethyl ether engine efficient, ultra-low emission combustion system |
| CN1691995A (en) * | 2002-10-07 | 2005-11-02 | 曼B与W狄赛尔公司 | Method of manufacturing a nozzle for a fuel valve in a diesel engine, and a nozzle |
| CN2781021Y (en) * | 2005-03-09 | 2006-05-17 | 无锡油泵油嘴研究所 | Injection nozzle for internal combustion engine premix combustion |
| CN101793206A (en) * | 2010-03-17 | 2010-08-04 | 大连理工大学 | Direction-injection diesel engine combustion chamber |
| CN102661193A (en) * | 2012-05-16 | 2012-09-12 | 大连理工大学 | Double-layer split-flow burning system of direct-injection diesel engine |
| CN103089506A (en) * | 2013-01-21 | 2013-05-08 | 江苏大学 | Device and method achieving liquid and gas dual fuel injection |
| CN103835803A (en) * | 2014-02-24 | 2014-06-04 | 大连理工大学 | Collision shunt combustion chamber of diesel engine |
| CN105545555A (en) * | 2016-01-04 | 2016-05-04 | 江苏大学 | Nozzle capable of achieving dual fuel injection |
| CN105909420A (en) * | 2016-06-14 | 2016-08-31 | 广西玉柴机器股份有限公司 | Combustion chamber capable of reducing soot in diesel engine cylinder |
| CN207829999U (en) * | 2018-02-07 | 2018-09-07 | 山东华源莱动内燃机有限公司 | A kind of diesel engine piston combustion chamber |
| CN110671190A (en) * | 2019-10-10 | 2020-01-10 | 天津大学 | Jet flow disturbance enhanced combustion system of pre-combustion chamber |
| CN211144630U (en) * | 2019-10-10 | 2020-07-31 | 天津大学 | Jet flow disturbance enhanced combustion system of pre-combustion chamber |
-
2020
- 2020-09-28 CN CN202011044900.8A patent/CN112112725A/en active Pending
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1691995A (en) * | 2002-10-07 | 2005-11-02 | 曼B与W狄赛尔公司 | Method of manufacturing a nozzle for a fuel valve in a diesel engine, and a nozzle |
| CN1470758A (en) * | 2003-06-26 | 2004-01-28 | 上海交通大学 | Dimethyl ether engine efficient, ultra-low emission combustion system |
| CN2781021Y (en) * | 2005-03-09 | 2006-05-17 | 无锡油泵油嘴研究所 | Injection nozzle for internal combustion engine premix combustion |
| CN101793206A (en) * | 2010-03-17 | 2010-08-04 | 大连理工大学 | Direction-injection diesel engine combustion chamber |
| CN102661193A (en) * | 2012-05-16 | 2012-09-12 | 大连理工大学 | Double-layer split-flow burning system of direct-injection diesel engine |
| CN103089506A (en) * | 2013-01-21 | 2013-05-08 | 江苏大学 | Device and method achieving liquid and gas dual fuel injection |
| CN103835803A (en) * | 2014-02-24 | 2014-06-04 | 大连理工大学 | Collision shunt combustion chamber of diesel engine |
| CN105545555A (en) * | 2016-01-04 | 2016-05-04 | 江苏大学 | Nozzle capable of achieving dual fuel injection |
| CN105909420A (en) * | 2016-06-14 | 2016-08-31 | 广西玉柴机器股份有限公司 | Combustion chamber capable of reducing soot in diesel engine cylinder |
| CN207829999U (en) * | 2018-02-07 | 2018-09-07 | 山东华源莱动内燃机有限公司 | A kind of diesel engine piston combustion chamber |
| CN110671190A (en) * | 2019-10-10 | 2020-01-10 | 天津大学 | Jet flow disturbance enhanced combustion system of pre-combustion chamber |
| CN211144630U (en) * | 2019-10-10 | 2020-07-31 | 天津大学 | Jet flow disturbance enhanced combustion system of pre-combustion chamber |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112879149A (en) * | 2021-01-25 | 2021-06-01 | 华中科技大学 | Asymmetric combustion chamber system suitable for high power density diesel engine |
| CN112879148A (en) * | 2021-01-25 | 2021-06-01 | 华中科技大学 | Asymmetric combustion chamber system suitable for high power density diesel engine |
| CN112780463A (en) * | 2021-03-04 | 2021-05-11 | 哈尔滨工程大学 | Dual-fuel engine adopting dual-gas spray pipe and step spray hole oil sprayer and combustion organization method thereof |
| CN114893289A (en) * | 2022-06-09 | 2022-08-12 | 北京理工大学 | Dredging type supercritical combustion system for diesel engine |
| CN115822803A (en) * | 2023-01-06 | 2023-03-21 | 潍柴动力股份有限公司 | Piston and engine |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112112725A (en) | Combustion chamber system suitable for high-power-density diesel engine | |
| CN105518274B (en) | For using gas as the combustion system of the internal combustion engine of fuel and method | |
| EP0544920B1 (en) | Direct injection type compression ignition internal combustion engine | |
| CN112127991B (en) | Side-mounted oil supply double-wall-collision diversion type oil-gas mixing system | |
| US4641617A (en) | Direct injection type internal combustion engine | |
| JP2010048212A (en) | Direct injection type gasoline engine | |
| CN114109587A (en) | Combustion apparatus and system | |
| JPS5979031A (en) | Direct-injection type diesel engine | |
| CN114233465A (en) | Ammonia fuel combustion system, engine and combustion control method | |
| CN110953066B (en) | Engine and in-cylinder split-layer combustion method | |
| KR950011685B1 (en) | Diesel engine | |
| JP4428273B2 (en) | In-cylinder direct injection internal combustion engine | |
| CN113417733A (en) | Fuel-air separation active control type ignition chamber system | |
| CN111734522B (en) | Combustion chamber of n-octanol internal combustion engine for combustion | |
| CN216518261U (en) | Ammonia fuel combustion system and engine | |
| CN216894617U (en) | Combustion system and engine | |
| CN101059111B (en) | Fuel oil jet method of direct-jet type gasoline engine adopting ignition chamber burning system | |
| JP3596351B2 (en) | Compression ignition type internal combustion engine | |
| CN216665738U (en) | Combustion apparatus and system | |
| CN115355080B (en) | Combustion system and gas engine | |
| KR19980024402A (en) | Combustion chamber of diesel engine | |
| SU799556A1 (en) | Compression ignition internal combustion engine | |
| CN114233464A (en) | Combustion system, engine and combustion control method | |
| JP2013170466A (en) | Internal combustion engine | |
| JP4026406B2 (en) | Direct-injection spark ignition internal combustion engine |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20201222 |
|
| RJ01 | Rejection of invention patent application after publication |