DK181315B1 - A large turbocharged two-stroke uniflow crosshead compression ignition internal combustion engine - Google Patents
A large turbocharged two-stroke uniflow crosshead compression ignition internal combustion engine Download PDFInfo
- Publication number
- DK181315B1 DK181315B1 DKPA202200371A DKPA202200371A DK181315B1 DK 181315 B1 DK181315 B1 DK 181315B1 DK PA202200371 A DKPA202200371 A DK PA202200371A DK PA202200371 A DKPA202200371 A DK PA202200371A DK 181315 B1 DK181315 B1 DK 181315B1
- Authority
- DK
- Denmark
- Prior art keywords
- ammonia
- fuel
- ignition
- cylinder
- engine
- Prior art date
Links
- 238000002485 combustion reaction Methods 0.000 title claims abstract description 101
- 230000006835 compression Effects 0.000 title claims abstract description 15
- 238000007906 compression Methods 0.000 title claims abstract description 15
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims abstract description 231
- 239000000446 fuel Substances 0.000 claims abstract description 125
- 229910021529 ammonia Inorganic materials 0.000 claims abstract description 115
- 239000012530 fluid Substances 0.000 claims abstract description 82
- 238000002347 injection Methods 0.000 claims abstract description 58
- 239000007924 injection Substances 0.000 claims abstract description 58
- 239000000295 fuel oil Substances 0.000 claims abstract description 50
- 239000007788 liquid Substances 0.000 claims abstract description 16
- 238000000034 method Methods 0.000 claims description 4
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 16
- 150000002430 hydrocarbons Chemical class 0.000 description 13
- 229930195733 hydrocarbon Natural products 0.000 description 12
- 239000004215 Carbon black (E152) Substances 0.000 description 10
- 229910002092 carbon dioxide Inorganic materials 0.000 description 8
- 239000001569 carbon dioxide Substances 0.000 description 8
- LCGLNKUTAGEVQW-UHFFFAOYSA-N Dimethyl ether Chemical compound COC LCGLNKUTAGEVQW-UHFFFAOYSA-N 0.000 description 4
- 239000007789 gas Substances 0.000 description 4
- 239000010763 heavy fuel oil Substances 0.000 description 4
- 230000001965 increasing effect Effects 0.000 description 4
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 235000011114 ammonium hydroxide Nutrition 0.000 description 2
- 230000008033 biological extinction Effects 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 239000002803 fossil fuel Substances 0.000 description 2
- 239000002737 fuel gas Substances 0.000 description 2
- 239000005431 greenhouse gas Substances 0.000 description 2
- 239000007791 liquid phase Substances 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 238000012544 monitoring process Methods 0.000 description 2
- 238000006722 reduction reaction Methods 0.000 description 2
- 230000002000 scavenging effect Effects 0.000 description 2
- 239000002028 Biomass Substances 0.000 description 1
- OTMSDBZUPAUEDD-UHFFFAOYSA-N Ethane Chemical compound CC OTMSDBZUPAUEDD-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 238000010531 catalytic reduction reaction Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 239000002283 diesel fuel Substances 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 239000003623 enhancer Substances 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- ZZUFCTLCJUWOSV-UHFFFAOYSA-N furosemide Chemical compound C1=C(Cl)C(S(=O)(=O)N)=CC(C(O)=O)=C1NCC1=CC=CO1 ZZUFCTLCJUWOSV-UHFFFAOYSA-N 0.000 description 1
- 239000007792 gaseous phase Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 239000013618 particulate matter Substances 0.000 description 1
- 239000003209 petroleum derivative Substances 0.000 description 1
- 239000012071 phase Substances 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 238000010791 quenching Methods 0.000 description 1
- 230000000171 quenching effect Effects 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 230000001960 triggered effect Effects 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D19/00—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
- F02D19/06—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures peculiar to engines working with pluralities of fuels, e.g. alternatively with light and heavy fuel oil, other than engines indifferent to the fuel consumed
- F02D19/08—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures peculiar to engines working with pluralities of fuels, e.g. alternatively with light and heavy fuel oil, other than engines indifferent to the fuel consumed simultaneously using pluralities of fuels
- F02D19/10—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures peculiar to engines working with pluralities of fuels, e.g. alternatively with light and heavy fuel oil, other than engines indifferent to the fuel consumed simultaneously using pluralities of fuels peculiar to compression-ignition engines in which the main fuel is gaseous
-
- 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
- F02B25/00—Engines characterised by using fresh charge for scavenging cylinders
- F02B25/02—Engines characterised by using fresh charge for scavenging cylinders using unidirectional scavenging
- F02B25/04—Engines having ports both in cylinder head and in cylinder wall near bottom of piston stroke
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D19/00—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
- F02D19/06—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures peculiar to engines working with pluralities of fuels, e.g. alternatively with light and heavy fuel oil, other than engines indifferent to the fuel consumed
-
- 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
- F02B43/00—Engines characterised by operating on gaseous fuels; Plants including such engines
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D19/00—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
- F02D19/06—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures peculiar to engines working with pluralities of fuels, e.g. alternatively with light and heavy fuel oil, other than engines indifferent to the fuel consumed
- F02D19/08—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures peculiar to engines working with pluralities of fuels, e.g. alternatively with light and heavy fuel oil, other than engines indifferent to the fuel consumed simultaneously using pluralities of fuels
- F02D19/10—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures peculiar to engines working with pluralities of fuels, e.g. alternatively with light and heavy fuel oil, other than engines indifferent to the fuel consumed simultaneously using pluralities of fuels peculiar to compression-ignition engines in which the main fuel is gaseous
- F02D19/105—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures peculiar to engines working with pluralities of fuels, e.g. alternatively with light and heavy fuel oil, other than engines indifferent to the fuel consumed simultaneously using pluralities of fuels peculiar to compression-ignition engines in which the main fuel is gaseous operating in a special mode, e.g. in a liquid fuel only mode for starting
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D37/00—Non-electrical conjoint control of two or more functions of engines, not otherwise provided for
- F02D37/02—Non-electrical conjoint control of two or more functions of engines, not otherwise provided for one of the functions being ignition
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/30—Controlling fuel injection
-
- 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
- F02M21/00—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form
- F02M21/02—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form for gaseous fuels
- F02M21/0203—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form for gaseous fuels characterised by the type of gaseous fuel
- F02M21/0206—Non-hydrocarbon fuels, e.g. hydrogen, ammonia or carbon monoxide
-
- 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
- F02M21/00—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form
- F02M21/02—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form for gaseous fuels
- F02M21/0218—Details on the gaseous fuel supply system, e.g. tanks, valves, pipes, pumps, rails, injectors or mixers
- F02M21/0248—Injectors
- F02M21/0275—Injectors for in-cylinder direct injection, e.g. injector combined with spark plug
-
- 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
- F02B75/00—Other engines
- F02B75/02—Engines characterised by their cycles, e.g. six-stroke
- F02B2075/022—Engines characterised by their cycles, e.g. six-stroke having less than six strokes per cycle
- F02B2075/025—Engines characterised by their cycles, e.g. six-stroke having less than six strokes per cycle two
-
- 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
- F02B2201/00—Fuels
- F02B2201/06—Dual fuel applications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D2700/00—Mechanical control of speed or power of a single cylinder piston engine
- F02D2700/02—Controlling by changing the air or fuel supply
- F02D2700/0202—Controlling by changing the air or fuel supply for engines working with gaseous fuel, including those working with an ignition liquid
-
- 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
- Y02T10/30—Use of alternative fuels, e.g. biofuels
Abstract
Described is a large turbocharged two-stoke uniflow crosshead compression ignition internal combustion engine, which has at least one mode of operation in which it is operated with both ammonia and an ignition fluid, such as fuel oil, as fuel for combustion in the engine, the engine comprising: - at least one cylinder with a cylinder liner (1) and a reciprocating piston (10) therein and a cylinder cover (22) covering the cylinder, - a combustion chamber formed inside the cylinder between the reciprocating piston (10) and the cylinder cover (22), - an ammonia fuel system (30) configured for supplying pressurized ammonia to at least one ammonia fuel valve (50) that is arranged in the cylinder cover (22) or in the cylinder liner (1), and - an ignition fluid system (40) configured for supplying pressurized ignition fluid to at least one ignition liquid valve (50) that is arranged in the cylinder cover (22) or in the cylinder liner (1). The engine is peculiar in that the ignition fluid system (40) is configured to supply ignition fluid into the combustion chamber with an injection duration of at least 20 % of a determined duration of the ammonia fuel combustion. Hence, by injecting the ignition fluid into the combustion chamber of the cylinder of an internal combustion engine over a longer period of time in relation to known practice a more complete burning of the ammonia is ensured. Further, as the full rate fuel oil injection system may be used, the pilot fuel oil injection system may be omitted, hence providing a considerably cost reduction and better space for installing fuel injection valves in the cylinder cover. In addition, during dual-fuel operation with both ammonia and ignition fluid, such as fuel oil, the fuel oil injection system is also kept running, and is thereby kept clean and ready for switching from ammonia dual-fuel operation to fuel oil operation.
Description
DK 181315 B1 1
The present invention relates to a large turbocharged two-stoke uniflow crosshead compression ignition internal combustion engine, which has at least one mode of operation in which it is operated with both ammonia and an ignition fluid, such as fuel oil, as fuel for combustion in the engine, the engine comprising: - at least one cylinder with a cylinder liner and a reciprocating piston therein and a cylinder cover covering the cylinder, - a combustion chamber formed inside the cylinder between the reciprocating piston and the cylinder cover, -an ammonia fuel system configured for supplying pressurized ammonia to at least one ammonia fuel valve that is arranged in the cylinder cover or in the cylinder liner, and - an ignition fluid system configured for supplying pressurized ignition fluid to at least one ignition liquid valve that is arranged in the cylinder cover or in the cylinder liner.
Large turbocharged two-stroke uniflow crosshead compression ignition internal combustion engine are typically used as prime movers in large ocean going ships, such as container ships or in power plants. Very often, these engines are operated with heavy fuel oil or with fuel oil. The sheer size, weight, and power output render them completely different from common combustion engines and place large two-stroke turbocharged compression-ignited internal combustion engines in a class for themselves.
Internal combustion engines have in the past mainly been operated with hydrocarbon fuels, such as fuel oil, e.g. diesel oil, or fuel gas, e.g. natural gas or petroleum gas. The combustion of hydrocarbon fuels releases carbon dioxide (CO), as well as other greenhouse gases that contribute to atmospheric pollution and climate change. Unlike
DK 181315 B1 2 fossil fuel impurities that result in byproduct emissions, CO; is an unavoidable result of hydrocarbon combustion. The energy density and CO; footprint of a fuel depend on the hydrocarbon chain length and the complexity of its hydrocarbon molecules. Hence, gaseous hydrocarbon fuels have a lower footprint than liquid hydrocarbon fuels, with the drawback that gaseous hydrocarbon fuels are more challenging and costly to handle and store. In order to reduce the CO» footprint, non-hydrocarbon fuels are being investigated.
Ammonia is a product obtained from fossil fuels, biomass, or renewable sources (wind, solar, hydro, or thermal), and when generated by renewable sources, ammonia will have virtually no carbon footprint or emit any CO», SOx, particulate matter, or unburned hydrocarbons when combusted. Currently, ammonia therefor enjoys very high interest as fuel for internal combustion engines mainly because it may be produced in an climate friendly way by use of electricity from renewable energy sources, such as sun, wind and wave energy and because the combustion of ammonia per se takes place without formation of carbon containing greenhouse gases, such as carbon dioxide.
In WO 2020/252518 Al is described a large turbocharged two-stroke uniflow crosshead compression ignition internal combustion engine of the kind mentioned in the introduction.
When ammonia is used as fuel for an internal combustion engine, the engine may be operated according to the Otto principle where ammonia fuel is introduced at relatively low pressure during the compression stroke of the piston, or the engine may be operated after the Diesel principle, where the ammonia fuel is injected at high pressure into the combustion chamber when piston is close to top dead center (TDC). During the ammonia fuel injection and combustion phase of the piston cycle the cylinder pressure is undergoing dramatic changes in level both due to compression/expansion of the chamber and due to the combustion taking place.
Ammonia has been tested and used at a minor scale in small spark-ignition internal combustion engines but has not yet been used in larger scale to power compression- ignition internal combustion engines.
DK 181315 B1 3
There are several challenges with using ammonia as a fuel. One challenge is the low power density compared to typical hydrocarbon fuels, resulting in a significantly larger volume of fuel that needs to be injected and thus resulting in a larger flow. Such a larger flow may cause flame extinction, i.e. although ignition occurs at the very start of the injection event, the following large flow and the resulting high speed of the fuel jet extinguishes (blows out) the flame. Another challenge is ammonia’s low willingness to ignite (low flammability) compared to liquid hydrocarbon fuels. Yet another challenge is ammonia’s high evaporative cooling that causes the fuel to cool upon injection, thus increasing the ignition energy required. Due to the high evaporative cooling high temperatures in the combustion chamber are a prerequisite for stable combustion. The combination of these challenges has so far prevented the use of ammonia as the main fuel in compression ignition engines.
Internal combustion engine being operable on two different fuels is normally referred to as dual-fuel engines. The two different fuels for dual-fuel engines normally consist of a fuel oil, such as heavy fuel oil or diesel, which are compression ignitable, and another fuel, such as gaseous fuel, for example, ammonia, methanol, LPG, LNG, ethane, which all require an ignition fluid, e.g. in form of a pilot fuel oil to be added.
Accordingly, the existing technical solution concept for dual-fuel engines running on ammonia and fuel oil is that the engine run at its maximum rating on oil fuel alone, or run at maximum rating on ammonia fuel with a minimum of pilot fuel oil for ignition of the ammonia fuel. The existing concept involves a fuel oil injection system optimized for delivery of full rate portions of fuel oil, an ammonia fuel system optimized for full rate ammonia running and a pilot fuel oil system optimized for ammonia ignition with the lowest possible pilot fuel oil portions, for example by pilot fuel oil injection into a pre-chamber. Further, some known dual-fuel engines use the full rate fuel oil injection system also for pilot fuel oil injection, where the pilot fuel oil portion size range between 1.5-5% of the full rate portions, when running on gaseous fuel.
However, there are problems associated with the existing dual-fuel concept engines, such as ammonia and fuel oil fueled engines, because it is complicated in that it
DK 181315 B1 4 comprises the pilot fuel oil injection system. Furthermore, the dual-fuel concept involves that the full rate fuel oil injection system is not operated during ammonia fuel running. This means a risk of deposit formation in the nozzle holes of the injection valves of the full rate fuel oil injection system during ammonia fuel running, and that the full rate fuel oil injection system may therefore not work properly, when switching from ammonia operation to fuel oil operation is attempted. Further, ammonia has a laminar flame velocity that is almost 10 times lower than that of most hydrocarbons, hence quenching/extinction of the flame may happen at even low turbulence levels, and it may therefore be difficult to maintain burning of the ammonia by using the full rate fuel oil injection system as applied for known fuel oil/gas dual-fuel engines, as this would not ensure ignition and burning of all the ammonia fuel. The injection duration of the fuel oil in the pilot fuel oil injection system is typically about 1 degree crank angle, which only ensures ignition of the ammonia, but not complete burning of all the ammonia fuel.
It is an object of the present invention to provide a large turbocharged two-stoke uniflow crosshead compression ignition internal combustion engine of the kind mentioned in the introduction, where the above mentioned challenges are at least significantly reduced.
The foregoing and other objects are achieved by the features of the independent claims.
Further implementation forms are apparent from the dependent claims, the description, — and the figures.
According to a first aspect, there is provided a large turbocharged two-stoke uniflow crosshead compression ignition internal combustion engine, which has at least one mode of operation in which it is operated with both ammonia and an ignition fluid, such as fuel oil, as fuel for combustion in the engine, the engine comprising: - at least one cylinder with a cylinder liner and a reciprocating piston therein and a cylinder cover covering the cylinder,
DK 181315 B1 - a combustion chamber formed inside the cylinder between the reciprocating piston and the cylinder cover, - an ammonia fuel system configured for supplying pressurized ammonia to at least one ammonia fuel valve that is arranged in the cylinder cover or in the cylinder liner, and 5 -an ignition fluid system configured for supplying pressurized ignition fluid to at least one ignition liquid valve that is arranged in the cylinder cover or in the cylinder liner, and being characterized in that the ignition fluid system is configured to supply ignition fluid into the combustion chamber with an injection duration of at least 20 % of a determined duration of the ammonia fuel combustion.
The duration of the ammonia fuel combustion is determined by the engine control system according to the actual speed of the engine.
Hence, by injecting the ignition fluid into the combustion chamber of the cylinder of — aninternal combustion engine over a longer period of time in relation to known practice a more complete burning of the ammonia is ensured. Further, as the full rate fuel oil injection system may be used, the pilot fuel oil injection system may be omitted, hence providing a considerably cost reduction and better space for installing fuel injection valves in the cylinder cover. In addition, during dual-fuel operation with both ammonia and ignition fluid, such as fuel oil, the fuel oil injection system is also kept running, and is thereby kept clean and ready for switching from ammonia dual-fuel operation to fuel oil operation.
In order to ensure a higher, preferably complete combustion rate of the ammonia the ignition fluid system may be configured to supply ignition fluid into the combustion chamber with an injection duration of at least 50 %, preferably at least 80 % and most preferably at least 95 % of the determined duration of the ammonia fuel combustion.
The ignition fluid system may be configured to supply ignition fluid into the combustion chamber with an injection duration increasing from 2 degrees crank angle at low engine speed to 20 degrees crank angle at full rate engine speed. Low engine speed is in this context defined as the lowest possible engine speed.
DK 181315 B1 6
The ignition fluid system may be configured to supply ignition fluid into the combustion chamber continuously or intermittently over the injection duration. If the ignition fluid system is configured for intermittent injection, the number of injection may be predetermined to between 2 and 10 injections, preferably 5, or it may be variable and determined by a control system monitoring different engine operation parameters, such as cylinder pressure, that indicate the combustion performance and thus the burning of the ammonia.
The ignition fluid system may be configured to supply ignition fluid into the combustion chamber in an amount ranging to between 5 and 50 %, preferably between and 40 % and most preferably 25 and 35 % of the amount required for full speed rate if operated solely on ignition fluid, such as fuel oil.
The ammonia fuel system may be configured to supply ammonia into the combustion 15 chamber in an amount of at least 60 %, preferably at least 70 % and most preferably at least 95 % of the amount of fuel required for full speed operation of the engine. By reducing the size of the ammonia fuel system the cost is reduced correspondingly.
In an embodiment of the invention the ammonia fuel valve may be connected to a pre- chamber that is connected by an opening to the combustion chamber. Hence, by injecting the ammonia fuel into the combustion chamber via such an pre-chamber a significant deceleration of the fuel is caused before the fuel enters the combustion chamber from the opening, and further the pre-chamber can serve as a preheating chamber. Thus, the speed of the fuel is reduced when enters the combustion chamber through the opening and the temperature of the fuel is increased when entering the combustion chamber, thereby at least partially overcoming the challenges with ammonia as a fuel for a compression igniting internal combustion engine mentioned above.
In such an embodiment of the invention, the engine the ignition fluid valve may be associated with the pre-chamber, the ignition fluid valve having an ignition fluid nozzle with nozzle holes and the ignition fluid valve is coupled to a source of pressurized ignition fluid. Thus, an ignition fluid can be mixed with the ammonia in the pre-
DK 181315 B1 7 chamber for enhancing reliable ignition of the ammonia. By injecting the ignition fluid with high pressure in the pre-chamber it is ensured that the ignition fluid is well dispersed into the ammonia and ensures that the ignition fluid is already well mixed with the ammonia when the mixture enters the combustion chamber.
The pre-chamber may be formed in an insert arranged in the cylinder cover. Thus, if there is damage to the pre-chamber or to the opening between the pre-chamber and the combustion chamber, the pre-chamber can be easily replaced by swapping the insert, without needing to work on (machine) the complete cylinder cover.
Further, the pre-chamber may be formed together with the ammonia fuel valve as a single unit, and wherein the single unit is an insert arranged in the cylinder cover. Thus, the pre-chamber and the ammonia fuel valve can be installed in the cylinder cover in a single operation.
According to a second aspect, there is provided a method for operating a large turbocharged two-stoke uniflow crosshead compression ignition internal combustion engine, which has at least one mode of operation in which it is operated with both ammonia and an ignition fluid, such as fuel oil, as fuel for combustion in the engine, the engine comprising: - at least one cylinder with a cylinder liner and a reciprocating piston therein and a cylinder cover covering the cylinder, - a combustion chamber formed inside the cylinder between the reciprocating piston and the cylinder cover, -an ammonia fuel system configured for supplying pressurized ammonia to at least one ammonia fuel valve that is arranged in the cylinder cover or in the cylinder liner, and - an ignition fluid system configured for supplying pressurized ignition fluid to at least one ignition liquid valve that is arranged in the cylinder cover or in the cylinder liner, and said method being characterized in that the ignition fluid is supplied into the combustion chamber with an injection duration of at least 20 % of a determined duration of the ammonia fuel combustion.
DK 181315 B1 8
The invention will be explained in more details with reference to the example embodiments shown in the drawings, in which:
Fig. 1 shows an elevated front view of a large two-stroke diesel engine according to an example embodiment,
Fig. 2 shows an elevated side view of the large two-stroke engine of Fig. 1, and
Fig. 3 shows a diagrammatic representation of the large two-stroke engine according to Fig. 1.
In the following detailed description, a compression igniting internal combustion engine according to the invention will be described with reference to a large two-stroke uniflow scavenged internal combustion engine with crossheads, but it is understood that the internal combustion engine could be of another type.
Figs. 1, 2, and 3 show a large low-speed turbocharged two-stroke diesel engine with a crankshaft 8 and crossheads 9. Fig. 3 shows a diagrammatic representation of a large low-speed turbocharged two-stroke diesel engine with its intake and exhaust systems.
In this example embodiment, the engine has six cylinders 1 in line. Large low-speed turbocharged two-stroke diesel engines have typically between four and fourteen cylinders 1 in line, carried by a cylinder frame 23 that is carried by an engine frame 11.
The engine may e.g. be used as the main engine in a marine vessel or as a stationary engine for operating a generator in a power station. The total output of the engine may, for example, range from 1,000 to 110,000 kW.
The engine is in this example embodiment a dual-fuel compression-ignited engine of the two-stroke uniflow type with scavenging ports 18 in the lower region of the cylinder liners 1 and a central exhaust valve 4 at the top of each cylinder liner 1. The engine has
DK 181315 B1 9 at least one mode of operation in which it is operated with both ammonia or an ammonia-based fuel and an ignition fluid, such as fuel oil. The engine may further have at least one conventional fuel mode in which the engine is operated on conventional fuel, e.g. fuel oil (marine diesel), or heavy fuel oil.
During operation of the engine scavenge air is passed from a scavenge air receiver 2 to the scavenge ports 18 of the individual cylinders 1. A piston 10 that reciprocates in the cylinder liner 1 between the bottom dead center (BDC) and top dead center (TDC) compresses the scavenge air. Fuel in form of ammonia and ignition fluid is injected through fuel valves 50 that are arranged in the cylinder cover 22 into the combustion chamber in the cylinder liner 1. Ammonia and ignition fluid are supplied from an ammonia fuel supply system 30 and from an ignition fuel supply system 40, respectively. The injection of ammonia may take place during the stroke of the piston 10 towards TDC at relatively low pressure or at or near TDC at relatively high pressure.
The injection of ignition fluid always takes place at high pressure at or near TDC.
Combustion follows, and exhaust gas is generated. Each cylinder cover 22 is provided with two or more fuel valves 50. The fuel valves 50 may be configured to inject only one specific type of fuel, ammonia and in this case ignition fluid, respectively, and accordingly, there will be two or more fuel valves 50 for injecting ammonia and two or more fuel valves 50 for injecting ignition fluid in form of e.g. conventional fuel into the combustion chamber. Hence, the engine will have four or more fuel valves 50. In case the fuel valves 50 are suitable for injecting both ammonia and conventional fuel simultaneously either premixed or through separate nozzle holes, there can be two or more fuel valves 50 for each cylinder. The fuel valves 50 are arranged in the cylinder — cover 22 around the central exhaust valve 4. The ignition fluid is e.g. dimethyl ether (DME) or fuel oil, but can also be another form of ignition enhancer, such as hydrogen.
Since the engine is a dual-fuel engine it may also be operated in conventional fuel mode in which the engine is operated only on the ignition fluid, such as conventional fuel, e.g. fuel oil (marine diesel), or heavy fuel oil. In an embodiment, ammonia fuel valves 50° are arranged along the cylinder liner (shown by the interrupted lines) and admit the ammonia fuel at relatively low pressure into the cylinder liner 1 before the piston 10 passes the ammonia fuel valves 50° on its way from BDC to TDC. Thus, the piston 10 compresses a mixture of scavenging air and fuel. Timed ignition at or near TDC is
DK 181315 B1 10 triggered by ignition fluid injection. In the embodiment with the ammonia fuel valves 50’ the pressure at which the fuel is admitted is substantially lower than the pressure at which the fuel is injected in the embodiment with the fuel valves 50 in the cylinder cover 22. Hence, the pressure at which the ammonia fuel supply system 30 needs to deliver fuel can be significantly lower, and/or pressure boosters, that are often used in the fuel valve 50 that are located in the cylinder cover can be avoided.
When the exhaust valve 4 is opened, the exhaust gas flows through an exhaust duct associated with the cylinders into an exhaust gas receiver 3 and onwards through a first exhaust conduit 19 via a Selective Catalytic Reduction (SCR) reactor 38 to a turbine 6 of a turbocharger 5, from which the exhaust gas flows away through a second exhaust conduit via an economizer 20 to an outlet 21 and into the atmosphere. The SCR reactor reduces emissions, in particular NOx emissions. — Through a shaft, the turbine 6 drives a compressor 7 supplied with fresh air via an air inlet 12. The compressor 7 delivers pressurized scavenge air to a scavenge air conduit 13 leading to the scavenge air receiver 2. The scavenge air in the scavenge air conduit 13 passes an intercooler 14 for cooling the scavenge air.
The cooled scavenge air passes via an auxiliary blower 16 driven by an electric motor 17 that pressurizes the scavenge air flow when the compressor 7 of the turbocharger 5 does not deliver sufficient pressure for the scavenge air receiver 2, i.e. in low or partial load conditions of the engine. At higher engine loads the turbocharger compressor 7 delivers sufficient compressed scavenge air and then the auxiliary blower 16 is bypassed via a non-return valve 15 and the electric motor 17 is deactivated.
The ammonia is supplied to the ammonia valves 50 at a substantially stable pressure and temperature and may be supplied to the ammonia valves 50 in the liquid phase or in the gaseous phase. The ammonia liquid phase can be aqueous ammonia (ammonia- water blend).
According to the invention the ignition fluid is injected into the combustion chamber of the cylinder of the internal combustion engine over a longer period of time in relation
DK 181315 B1 11 to known practice, whereby a more complete burning of the ammonia is obtained.
According to known practice the ignition fluid is injected over about 1 degree crank angle corresponding to 5 to 10 % of the duration of the ammonia fuel combustion.
However, according to the invention the ignition fluid system 40 is configured to supply ignition fluid into the combustion chamber with an injection duration of at least 20 % of a determined duration of the ammonia fuel combustion.
Besides from a more complete burning of the ammonia, an additional advantages by the invention is that the full rate fuel oil injection system may be used for the injection of ignition fluid, because of the necessary amount of ignition fluid to be used. This implies that the pilot fuel oil injection system may be omitted, hence providing a considerably cost reduction and better space for installing fuel injection valves in the cylinder cover. In addition, the fuel oil injection system is also kept running in all operation modes of the engine, and is thereby kept clean.
With a view to produce as little CO, as possible by the operation of the engine with simultaneous burning of both ammonia and an ignition fluid, the amount of ignition fluid should be kept as little as possible without compromising the ammonia burning.
However, in some situations, to ensure a complete combustion of the ammonia the ignition fluid should be injected into the combustion chamber with an injection duration of at least 50 %, or even at least 80 % or at least 95 % of the determined duration of the ammonia fuel combustion. It is also possible that the ignition fluid should be injected into the combustion chamber with an injection duration of 100 % of the determined duration of the ammonia fuel combustion.
The ignition fluid system 40 may be configured to supply ignition fluid into the combustion chamber with an injection duration increasing from about 2 degrees crank angle at low engine speed to about 20 degrees crank angle at full rate engine speed.
The ignition fluid system may be configured to supply ignition fluid into the combustion chamber continuously or intermittently over the injection duration. If the ignition fluid system is configured for intermittent injection, the number of injection may be predetermined to between 2 and 10 injections, preferably 5, or it may be
DK 181315 B1 12 variable and determined by a control system monitoring different engine operation parameters, such as cylinder pressure, that indicate the combustion performance and thus the burning of the ammonia.
The ignition fluid system may be configured to supply ignition fluid into the combustion chamber in an amount ranging to between 5 and 50 %, preferably between 15 and 40 % and most preferably 25 and 35 % of the amount required for full speed rate if operated solely on ignition fluid, such as fuel oil.
The ammonia fuel system may be configured to supply ammonia into the combustion chamber in an amount of at least 60 %, preferably at least 70 % and most preferably at least 95 %. By reducing the size of the ammonia fuel system the cost is reduced correspondingly.
Claims (10)
Priority Applications (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DKPA202200371A DK181315B1 (en) | 2022-04-22 | 2022-04-22 | A large turbocharged two-stroke uniflow crosshead compression ignition internal combustion engine |
| JP2023061063A JP7307293B1 (en) | 2022-04-22 | 2023-04-05 | Large turbocharged two-stroke uniflow crosshead compression ignition internal combustion engine and method of operation thereof |
| CN202310368943.9A CN116201644A (en) | 2022-04-22 | 2023-04-07 | Large-scale turbocharged two-stroke uniflow crosshead compression ignition internal combustion engine and operating method |
| KR1020230052837A KR102628782B1 (en) | 2022-04-22 | 2023-04-21 | A large turbocharged two-stroke uniflow crosshead compression ignition internal combustion engine and method for operating such engine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DKPA202200371A DK181315B1 (en) | 2022-04-22 | 2022-04-22 | A large turbocharged two-stroke uniflow crosshead compression ignition internal combustion engine |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| DK202200371A1 DK202200371A1 (en) | 2023-08-09 |
| DK181315B1 true DK181315B1 (en) | 2023-08-09 |
Family
ID=86517512
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DKPA202200371A DK181315B1 (en) | 2022-04-22 | 2022-04-22 | A large turbocharged two-stroke uniflow crosshead compression ignition internal combustion engine |
Country Status (4)
| Country | Link |
|---|---|
| JP (1) | JP7307293B1 (en) |
| KR (1) | KR102628782B1 (en) |
| CN (1) | CN116201644A (en) |
| DK (1) | DK181315B1 (en) |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2406479B1 (en) * | 2009-03-10 | 2015-08-05 | Sturman Digital Systems, LLC | Dual fuel compression ignition engines and methods |
| US8534237B2 (en) * | 2010-04-22 | 2013-09-17 | Toyota Jidosha Kabushiki Kaisha | Control system of internal combustion engine |
| US8904994B2 (en) | 2010-04-26 | 2014-12-09 | Toyota Jidosha Kabushiki Kaisha | Ammonia burning internal combustion engine |
| US20110259285A1 (en) * | 2010-04-26 | 2011-10-27 | Toyota Jidosha Kabushiki Kaisha | Ammonia burning internal combustion engine |
| JP5618803B2 (en) * | 2010-12-09 | 2014-11-05 | 日立造船株式会社 | 2-stroke engine and 4-stroke engine |
| DK178072B1 (en) * | 2014-01-06 | 2015-04-27 | Man Diesel & Turbo Deutschland | A method of operating an internal combustion engine |
| WO2020183522A1 (en) * | 2019-03-08 | 2020-09-17 | Ｊｆｅエンジニアリング株式会社 | Diesel engine |
| JP2022537229A (en) | 2019-06-19 | 2022-08-25 | コモンウェルス サイエンティフィック アンド インダストリアル リサーチ オーガナイゼーション | Method of injecting ammonia fuel into a reciprocating engine |
| DK180798B1 (en) * | 2020-07-15 | 2022-04-01 | Man Energy Solutions Filial Af Man Energy Solutions Se Tyskland | Internal combustion engine |
| CN114320572B (en) * | 2022-01-13 | 2022-12-02 | 天津大学 | Multi-combustion-mode ammonia fuel engine and control method thereof |
-
2022
- 2022-04-22 DK DKPA202200371A patent/DK181315B1/en active IP Right Grant
-
2023
- 2023-04-05 JP JP2023061063A patent/JP7307293B1/en active Active
- 2023-04-07 CN CN202310368943.9A patent/CN116201644A/en active Pending
- 2023-04-21 KR KR1020230052837A patent/KR102628782B1/en active IP Right Grant
Also Published As
| Publication number | Publication date |
|---|---|
| DK202200371A1 (en) | 2023-08-09 |
| JP7307293B1 (en) | 2023-07-11 |
| CN116201644A (en) | 2023-06-02 |
| JP2023160748A (en) | 2023-11-02 |
| KR20230150760A (en) | 2023-10-31 |
| KR102628782B1 (en) | 2024-01-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| DK180922B1 (en) | Compression-ignited internal combustion engine operating on ammonia and retrofit kit | |
| EA026829B1 (en) | Method of operating an engine utilizing a plurality of fuels | |
| KR101780693B1 (en) | A Method of operating an internal combustion engine, and an internal combustion engine operated by the method | |
| KR102330222B1 (en) | Large two-stroke uniflow scavenged engine with a gaseous fuel mode | |
| Krivopolianskii et al. | Control of the combustion process and emission formation in marine gas engines | |
| DK181315B1 (en) | A large turbocharged two-stroke uniflow crosshead compression ignition internal combustion engine | |
| US9869241B2 (en) | Split cycle engine and method of operation | |
| US20150377108A1 (en) | Dual fuel engine system | |
| KR20210008318A (en) | Internal combustion engine | |
| DK181138B1 (en) | Two-stroke uniflow scavenged crosshead internal combustion engine and method for operating such engine | |
| US20230203981A1 (en) | Gas exchange in internal combustion engines for increased efficiency | |
| JP7329713B1 (en) | Large turbocharged 2-stroke uniflow crosshead dual fuel internal combustion engine | |
| DK181454B1 (en) | A large two-stroke uniflow scavenged turbocharged internal combustion engine with a system for reducing nitrous oxide emissions and a method for reducing nitrous oxide emissions of such an engine | |
| KR102207883B1 (en) | Exhaust gas recirculation system and ship including the same | |
| Zaman et al. | An experimental investigation of natural gas injection timing on dual-fuel engine | |
| Serrano Reyes et al. | Prediction of hydrogen-heavy fuel combustion process with water addition in an adapted low speed two stroke diesel engine: Performance improvement | |
| Eng | Air-Fuel Control and Emissions for Gas Engines |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PAT | Application published |
Effective date: 20230809 |
|
| PME | Patent granted |
Effective date: 20230809 |