Assembly for direct injection of gaseous fuel into a cylinder of a two-stroke internal combustion piston engine and two-stroke internal combustion piston engine

Abstract

The present invention relates to an assembly (50) for direct injection of a gaseous fuel into a cylinder (100) of a two-stroke internal combustion piston engine (1), the assembly (50) comprising: an enclosure (102) enclosing a liquefied gas supply manifold (120, 120'), a liquefied gas return manifold (140, 140'), a liquefied gas high pressure pump unit (160) connected to the liquefied gas supply manifold (120, 120') and to the liquefied gas return manifold (140, 140'), The system further comprises: - a high pressure liquefied gas outlet (180) in the liquefied gas high pressure pump unit (160); - a heat exchanger unit (200) configured for evaporating and heating the liquefied gas and comprising a liquefied gas inlet (201) and a gaseous gas outlet (202), the liquefied gas inlet (201) being connected to the high pressure gas outlet (180) of the liquefied gas high pressure pump unit (160) by a fuel supply line (320); and - at least one gaseous gas fuel injector (220) connected to the heat exchanger unit.

Description

[Technical field]

[0001] The present invention relates to an assembly for direct injection of a gaseous fuel into a cylinder of a two-stroke internal combustion piston engine according to the preamble of claim 1. The present invention also relates to a two-stroke internal combustion piston engine equipped with a direct injection gaseous fuel supply system. [Background technology]

[0002] Internal combustion piston engines are widely used in land-based power plants and for mechanical power supply in ships to produce electrical power and / or propulsion.

[0003] A dual fuel engine uses a low pressure gaseous fuel, such as natural gas, which is mixed at relatively low pressure with intake air for entry into the engine cylinder. Under certain operating conditions, the air / gas fuel mixture delivered to the cylinder is compressed and then ignited using an ignition spark or a compression ignition pilot fuel, such as diesel, which is injected into the air / gas fuel mixture present in the cylinder.

[0004] Direct injection gas engines are also known as such in which a gaseous fuel, such as liquefied natural gas (LNG), is injected into the cylinder at high pressure while combustion is already underway in the cylinder from a diesel pilot. Direct injection gas engines run on gaseous fuel, and the diesel pilot provides ignition of the gaseous fuel.

[0005] DK179056B1 (Patent Document 1) discloses a fuel supply system for supplying high pressure gas to a large two-stroke compression ignition internal combustion engine. The engine is equipped with a fuel injection system for injecting the supplied high pressure gas into a combustion chamber of the engine. The fuel supply system has a supply conduit connecting an outlet of a liquefied gas storage tank to an inlet of a high pressure pump for transporting the liquefied gas from the liquefied gas storage tank to the high pressure pump, a transfer conduit connecting an outlet of the high pressure pump to an inlet of a high pressure vaporizer for transporting the high pressure liquefied gas from the high pressure pump to a high pressure vaporizer, and a supply conduit connecting an outlet of the high pressure vaporizer to an inlet of a fuel injection system of the engine for transporting the high pressure vaporized gas to a fuel injection system of the engine. The high pressure pump has two or more pump units. Each pump unit has a pump piston slidably arranged in a pump cylinder and a hydraulic drive piston slidably arranged in a drive cylinder with the drive piston coupled to the pump piston for driving the pump piston.

[0006] US918806 9 B2 (Patent Document 2) discloses an engine fuel system having a liquid and a gas fuel system, each of which injects fuel directly into the engine cylinder. The gas fuel system is a direct injection gas system that includes a liquefied gas reservoir, a liquefied gas pump, a liquefied gas vaporizer, and a gas fuel rail connected to a fuel injector.

[0007] A gaseous fuel direct injection fuel supply system must be configured so that substantially high pressure gas is supplied to gas injectors located in the cylinders of the engine.

[0008] All of the above prior art documents suggest controlling the operation of the gas fuel pump by a control fluid that operates a high pressure piston pump. Variable control of the high pressure pump requires a variable high pressure pump in the control fluid system. The prior art solutions suffer from the general problem of the complexity of the structure of the liquefied gas pump and its controllability.

[0009] It is an object of the present invention to provide an assembly for direct injection of gaseous fuel into the cylinders of a two-stroke internal combustion piston engine which is significantly improved compared to the solutions of the prior art.

[0010] It is an object of the present invention to provide a two-stroke internal combustion piston engine having a direct injection gaseous fuel supply system which is significantly improved compared to prior art solutions for large gas-operated two-stroke internal combustion piston engines. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] DK179056B1 [Patent Document 2] US9188069B2 Summary of the Invention

[0012] The object of the invention can be achieved substantially as disclosed in the independent claims and the other claims which describe different embodiments of the invention.

[0013] An assembly for directly injecting gaseous fuel into a cylinder of a two-stroke internal combustion piston engine includes: a liquefied gas supply manifold, a liquefied gas return manifold, an enclosure surrounding the liquefied gas supply manifold and the liquefied gas return manifold, a liquefied gas high pressure pump unit connected to the liquefied gas supply manifold and the liquefied gas return manifold, a high pressure liquefied gas outlet in the liquefied gas high pressure pump unit, a heat exchanger unit configured to evaporate the liquefied gas and heat the gaseous gas, the heat exchanger unit having a liquefied gas inlet and a gaseous gas outlet, the liquefied gas inlet being connected to the high pressure outlet of the liquefied gas high pressure pump unit by a fuel supply line, and at least one gaseous gas fuel injector connected to the heat exchanger unit.

[0014] Thus, the assembly is configured to pump liquefied gas in liquid phase, cryogenic condition and evaporate the pumped gas into gaseous form, which can be delivered to the cylinder by a gaseous fuel injector. A fuel injection system utilizing liquefied gas is provided for large two-stroke engines that can be easily modularized. Safety issues associated with gaseous fuel are addressed by a common enclosure for the liquefied gas supply manifold, the liquefied gas return manifold and the liquefied gas high pressure pump unit. The assembly is configured to be assembled on top of the engine, and thus can be easily retrofitted to existing large two-stroke engines.

[0015] According to one embodiment of the invention, the enclosure comprises an air inlet and an outlet connectable to a blower located in the assembly, which allows the outlet to be connected to the blower in order to transport any possible leaked fuel safely away from the engine.

[0016] According to one embodiment of the invention, the liquefied gas supply manifold within the enclosure is a single-walled manifold and the liquefied gas return manifold within the enclosure is a single-walled manifold.

[0017] According to one embodiment of the invention, the fuel supply line outside the enclosure comprises a separate double wall forming an intermediate space inside the double wall, and the enclosure comprises a lead-through block through which the fuel supply line is led from the enclosure to the heat exchanger unit, the lead-through block separating the intermediate space of the fuel supply line from the space of the enclosure.

[0018] According to one embodiment of the invention, the assembly comprises an air gas accumulator connected to an air gas outlet of the heat exchanger unit by a fuel supply line.

[0019] According to one embodiment of the present invention, the assembly comprises an enclosure, the assembly being configured for a multi-cylinder two-stroke internal combustion piston engine including several cylinders arranged in a line of cylinders, - the enclosure has the length of a row of cylinders; - The enclosure has an air inlet and an outlet at each end (opposite ends) of the enclosure.

[0020] According to one embodiment of the present invention, the assembly is configured for a multi-cylinder two-stroke internal combustion piston engine comprising several cylinders arranged in a row of cylinders, a liquefied gas supply manifold, a liquefied gas return manifold and a liquefied gas high pressure pump unit are disposed within the enclosure; The heat exchanger unit and the gas accumulator are arranged outside the enclosure.

[0021] According to one embodiment of the present invention, the liquefied gas supply manifold is an assembly of multiple gas supply manifold sections, one supply manifold section for each cylinder of the engine.

[0022] According to one embodiment of the present invention, the liquefied gas return manifold is an assembly of multiple gas return manifold sections, one return manifold section for each cylinder of the engine.

[0023] According to one embodiment of the present invention, the assembly comprises several fuel supply lines for cylinders of an engine, each fuel supply line having: one liquefied gas high pressure pump unit connected to a liquefied gas supply manifold and a liquefied gas return manifold; one heat exchanger unit configured to evaporate the liquefied gas and heat the gaseous gas; and It has one gas gas accumulator.

[0024] The two-stroke internal combustion piston engine of the present invention has more than one cylinder, each cylinder being provided with an assembly according to any of claims 1-9.

[0025] According to one embodiment of the invention, the enclosure has a length that extends from the first cylinder in a row of cylinders to the last cylinder in the row of cylinders of the engine.

[0026] According to one embodiment of the present invention, the enclosure, the liquefied gas supply manifold, the liquefied gas return manifold and the liquefied high pressure pump unit are located and mounted on top of the engine.

[0027] According to one embodiment of the present invention, the engine has one fuel supply line for each cylinder (100) of the engine.

[0028] The assembly of the present invention and its various embodiments are applicable to the use of liquefied combustible gases for the direct injection of gaseous fuels into the cylinders of internal combustion piston engines and combustion therein. For example, suitable fuel materials include liquefied ammonia, liquefied natural gas or liquefied petroleum gas.

[0029] The exemplary embodiments of the invention presented in this patent application should not be interpreted as bringing about limitations on the application of the appended claims. The verb "to have" is used in this patent application as an open limitation that does not exclude the presence of unrecited features. The features recited in the dependent claims may be freely combined with one another, unless expressly stated otherwise. The novel features which are believed to be characteristic of the invention are recited with particularity in the appended claims. [Brief description of the drawings]

[0030] The invention will be explained below with reference to the accompanying exemplary schematic drawings.

[0031] [Figure 1]1 illustrates a simplified assembly for direct injection of gaseous fuel into a cylinder of a two-stroke internal combustion piston engine according to an embodiment of the present invention. [Diagram 2] 1 shows a simplified assembly for direct injection of gaseous fuel into a cylinder of a two-stroke internal combustion piston engine according to another embodiment of the present invention. [Diagram 3] 1 shows a two-stroke internal combustion piston engine with an assembly for direct injection of gaseous fuel according to yet another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] FIG. 1 shows diagrammatically a simplified assembly 50 for direct injection of gaseous fuel into a cylinder 100 of a two-stroke internal combustion piston engine 1. The assembly is configured to inject gaseous fuel directly into one combustion chamber of the engine while pressurizing the fuel to the injection pressure of the liquid phase. The assembly 50 comprises a liquefied gas supply manifold section 120 and a liquefied gas return manifold section 140 arranged parallel to each other. In practice, the manifold sections are advantageously formed using pipes and flanges. In this case, the word section refers to the fact that the assembly in FIG. 1 is for one cylinder, whereas an engine usually has more than one cylinder. In this case, the manifold is formed of a respective number of manifold sections connected to each other by flanges. The assembly in FIG. 1 shows the minimum components of a fuel supply line for one cylinder of an engine. Also, if the engine has several rows of cylinders arranged one after the other, the engine comprises a corresponding number of assemblies 50 connected to each other such that the liquefied gas supply manifold 120' and the liquefied gas return manifold 140' extend from the first cylinder in the row of cylinders to the last cylinder in the row of cylinders (see FIG. 3). The liquefied gas supply manifold 120' is connected to the liquefied gas supply pipe 130 and the liquefied gas return manifold 140' is connected to the liquefied gas return pipe 150.

[0033] The assembly further comprises a liquefied gas high pressure pump unit 160 connected to the liquefied gas supply manifold section 120 and the liquefied gas return manifold section 140. The liquefied gas tends to heat up in the pump due to pumping and heat transfer from the surroundings. The pump comprises insulation to minimize undesired temperature rise of the liquefied gas in the pump during the pumping phase. In addition to the connection to the liquefied gas supply manifold section 120, the pump comprises a connection to the liquefied gas return manifold section 140. This is advantageous to keep the temperature of the liquefied gas in the pump low to at least minimize partial phase change of the liquefied gas to gas in the pump, so that part of the liquefied gas is directed through the pump and back to the liquefied gas return manifold to cool the pump unit 160. The liquefied gas in a cryogenic state is partially circulated through the liquefied gas high pressure pump unit 160 such that a portion of the liquefied gas flowing from the liquefied gas supply manifold 120 to the liquefied gas high pressure pump unit 160 is directed to the liquefied gas return manifold 140 for return to the source of liquefied gas. A majority of the liquefied gas flowing from the liquefied gas supply manifold 120 to the liquefied gas high pressure pump unit 160 is directed to the high pressure liquefied gas outlet 180 of the liquefied gas high pressure pump unit 160 at a high pressure resulting in the desired fuel injection pressure. The liquefied gas high pressure pump unit 160 preferably comprises a hydraulically operated piston pump. The pump is driven by high pressure hydraulic fluid such that the pump has a drive section where the hydraulic fluid is directed to reciprocate between the drive section and the piston of the pump.

[0034] The high pressure liquefied gas is conducted via a high pressure liquefied gas outlet 180 to a heat exchanger unit 200 configured to evaporate the liquefied gas into gas and heat the gaseous gas to a level suitable for injection into the engine. For this purpose, the heat exchanger unit 200 is in flow connection with the high pressure liquefied gas outlet 180 and at least one gaseous gas fuel injector 220. The heat exchanger unit 200 comprises a liquefied gas inlet 201 and a gaseous gas outlet 202, the liquefied gas inlet being connected to a high pressure outlet of the liquefied gas high pressure pump unit 160 by a fuel supply line 320, more specifically a second fuel supply line 340 outside the enclosure 102.

[0035] The assembly comprises an enclosure 102 enclosing the liquefied gas supply manifold section 120, the liquefied gas return manifold section 140 and the liquefied gas high pressure pump unit 160. The liquefied or gaseous gas containing components outside the enclosure 102 comprise a separate double wall 110 forming an intermediate space inside the double wall 110 bordering the inner space containing the gas. For example, a pipe comprises another pipe outside the inner pipe leaving an intermediate space between. A part of the fuel supply line 320 is inside the enclosure and may be called a first fuel supply line 321. A part of the fuel supply line 320 is outside the enclosure 102 and may be called a second fuel supply line 340. The first fuel supply line 321 is made of a single wall pipe and the second fuel supply line 340 is made of a double wall pipe. The assembly comprises a lead-through block 103 in the wall of the enclosure. The lead-through block 103 comprises a conduit 320' through which the first fuel supply line 321 inside the enclosure 102 and the second fuel supply line 340 outside the enclosure 102 are connected to each other. The lead-through block 103 separates the intermediate space of the fuel supply line 320 from the space of the enclosure 102. The lead-through block 103 also seals the connection of the inner space of the enclosure from the surroundings. A leak from the high pressure line 320 between the pump and the injector 220 is the most likely point of leakage, since in that part of the fuel supply line the pressure is rather high, for example 15 MPa. In case of failure of the first fuel supply line 321, the leakage will flow into the enclosure 102. Outside the enclosure, in case of failure of the second fuel supply line 340, the leakage will flow into the intermediate space of the line, which intermediate space is separated by the lead-through block 103 from the inner space of the enclosure 102. Since the volume of the portion of the first fuel supply line 321 inside the enclosure is very small, the large volume of the enclosure 102, together with the ventilation of the enclosure, easily handles leakage. If a leakage is observed, the corresponding pump can be stopped immediately, and the leakage amount remains relatively small compared to the ventilation amount of the enclosure 102.

[0036] The liquefied gas containing components in the enclosure have a single wall in contact with the inner space containing the liquefied gas. Possible gas leaks of the liquefied gas or gaseous gas containing components outside the enclosure 102 are detected and appropriately handled. Gas leaking from the second fuel supply line 340 into the intermediate space between the inner pipe and the outer pipe can be directed to another piping (not shown) for further handling. Thus, the liquefied gas supply manifold section 120 is a single-wall manifold and the liquefied gas return manifold section 140 is each a single-wall manifold. It should be noted that the fuel gas is in liquid phase until it evaporates in the heat exchanger unit 200.

[0037] This assembly can be utilized as a gaseous fuel injection module for one cylinder of an engine, and when applied to a multi-cylinder engine, the engine will have an assembly for each of its cylinders, with the liquefied gas supply manifold sections 120 of the assemblies connected to each other and the liquefied gas return manifold sections 140 of the assemblies each connected to each other to form manifolds that extend parallel to each other from the first cylinder to the last cylinder in a row of cylinders in the engine.

[0038] To facilitate ventilation and removal of gaseous fuel that may have leaked from the enclosure 102 of the assembly 50, an air inlet 240 disposed in relation to the assembly 50 and an air outlet 260 connected to a blower 280 are provided. The blower 280 may consist of one or more blowers suitably connected to obtain the desired flow rate and pressure within the enclosure 102. It should be noted that even if several assemblies are provided to supply fuel injection to several cylinders of an engine, only one air outlet is required.

[0039] FIG. 2 shows diagrammatically an assembly 5 for direct injection of gaseous fuel into a cylinder 100 of a two-stroke internal combustion piston engine, further developed from the assembly shown in FIG. 1. In FIG. 1, the gas supply line 320, in particular the part of the second supply line 340 containing the gaseous fuel, has a sufficient volume to act as a fuel accumulator. If not shown here, the exchanger unit 200 is also connected to a suitable heat source. The assembly is configured to pressurize and vaporize the liquefied gas fuel and to inject the gaseous fuel directly into one combustion chamber. The assembly 50 shown in FIG. 2 is otherwise similar to that shown in FIG. 1, but here the assembly includes a separate gaseous gas accumulator 300 connected by a fuel supply line 320 to the gaseous gas outlet of the heat exchanger unit.

[0040] Figure 3 shows an assembly for direct injection of gaseous fuel into the cylinders of a two-stroke multi-cylinder internal combustion piston engine 1. The large two-stroke crosshead engine shown in Figure 3 has a row of one or more, typically more than six, cylinders 100. Large two-stroke engines for which the gaseous fuel supply system according to the invention is particularly intended are slow speed crosshead engines with cylinder bore diameters of about 50 cm to 1 m and stroke lengths of about 2.5 to 3.0 m.

[0041] Each of the cylinders 100 comprises an assembly according to Fig. 2. In the embodiment of Fig. 3, the assembly comprises at least two fuel injectors 220 for each cylinder, both connected to a shared or common accumulator 300. For example, depending on the engine power and bore diameter, it may be more advantageous to provide each cylinder with three injectors connected to a common accumulator 300. When applied to a multi-cylinder two-stroke engine, the enclosure 102 has a length L that substantially corresponds to the length of a row of cylinders 100 of the engine. In other words, the enclosure extends from the first cylinder of a row of cylinders of the engine 1 to the last cylinder of the row of cylinders.

[0042] The enclosure 102 comprises an air inlet 240 and an outlet 280 at either end of the enclosure 102. The enclosure may be formed of several separate sections connected to each other. The air outlet 260 is connected to a blower 280. It should be noted that only one air outlet is necessary, but the enclosure may comprise two or even more outlets, even if instead of one air outlet several assemblies according to FIG. 2 are provided to supply fuel injection to several cylinders of an engine.

[0043] The enclosure 102 completely encloses the liquefied gas supply manifold 120' and the liquefied gas return manifold 140', as well as the liquefied gas high pressure pump unit 160. In this manner, the liquefied gas containing components within the enclosure have a single wall that bounds the interior space containing the liquefied gas from the common enclosure. Thus, the liquefied gas supply manifold 120' and the liquefied gas return manifold 140' may each be referred to as a single wall manifold. The liquefied or gas containing components outside the enclosure 102 have a double wall that is in contact with the gas fuel supply line 320 that contains the gas and supplies the gas to the injector 220.

[0044] The invention can be described such that the engine has one fuel supply line for each of the engine's cylinders 100. The assembly therefore has several fuel supply lines for the engine's cylinders, each fuel supply line comprising one liquefied gas high pressure pump unit 160 connected to a liquefied gas supply manifold 120' and a liquefied gas return manifold 140', one heat exchanger unit 200 configured to evaporate the liquefied gas and heat the gaseous gas, and one gaseous gas accumulator to which several fuel injectors 220 are connected to receive the gaseous fuel. 300 has.

[0045] The liquefied gas supply manifold 120' is an assembly of multiple gas supply manifold sections 120, with one supply manifold section for each cylinder 100 of the engine, as shown in Figure 2. The liquefied gas return manifold 140' is an assembly of multiple gas return manifold sections 140, with one return manifold section for each cylinder of the engine, respectively. There is a liquefied gas supply pipe 130 that serves all cylinders of the engine, and a liquefied gas return pipe 150.

[0046] The liquefied gas supply manifold 120' and the liquefied gas return manifold 140', and the liquefied gas high pressure pump unit 160 are each disposed within a common enclosure 102, and a heat exchanger unit 200 and a gas accumulator 300 are located outside the enclosure 102. Accumulators for each cylinder can be installed near the injectors on top of the respective cylinder head. The enclosure 102 is provided for safety reasons. In case of a leak in the fuel system inside the enclosure, the leaked gas can be directed for further processing by the blower 280. A leak from the high pressure line between the pump and the injector 220 is the most likely point of leakage. The large volume of the enclosure 102 and its ventilation handles the leakage easily, since the volume of the single wall high pressure line is very small. If a leak is observed, the corresponding pump can be immediately and quickly stopped, and the leaked gas volume remains relatively small compared to the ventilation volume of the enclosure 102.

[0047] As shown in Figure 3, the assembly comprising the enclosure 102, the liquefied gas supply manifold 120', the liquefied gas return manifold 140' and the liquefied high pressure pump unit 160 is placed on top of the engine. The assembly is supported by a suitable support structure attached to the engine. Advantageously, the assembly is placed above the cylinder head of the engine.

[0048] Although the present invention has been described herein by way of example in connection with what are presently considered to be the most preferred embodiments, it will be understood that the invention is not limited to the disclosed embodiments, but is intended to cover various combinations or modifications of its features, and several other applications that fall within the scope of the invention, as defined in the appended claims. Details described in connection with any of the above embodiments can also be used in connection with other embodiments, where such combination is technically possible.

Claims

1. 1. A fuel injection module for direct injection of a gaseous fuel for one cylinder of a multi-cylinder two-stroke internal combustion piston engine, said fuel injection module comprising: A common enclosure, wherein the common enclosure includes a liquefied gas supply manifold section; a liquefied gas return manifold section disposed within the common enclosure in parallel with the liquefied gas supply manifold section; a liquefied gas high pressure pump unit connected to the liquefied gas supply manifold section and the liquefied gas return manifold section; a high-pressure liquefied gas outlet in the liquefied gas high-pressure pump unit; a common enclosure surrounding the The fuel injection module further comprises, external to the common enclosure: a heat exchanger unit configured to evaporate a liquefied gas and heat the evaporated gaseous gas from the liquefied gas, the heat exchanger unit having a liquefied gas inlet and a gaseous gas outlet, the liquefied gas inlet being connected to the high-pressure liquefied gas outlet of the liquefied gas high-pressure pump unit by a fuel supply line; at least one gas fuel injector connected to the heat exchanger unit; having the fuel supply line outside the common enclosure comprises a separate double wall forming an intermediate space inside the double wall, the common enclosure comprises a lead-through block via which a portion of the fuel supply line outside the common enclosure and a portion of the fuel supply line inside the common enclosure are connected to each other, the lead-through block separating the intermediate space of the fuel supply line from an inner space of the common enclosure; Fuel injection module.

2. the liquefied gas supply manifold section within the common enclosure is a single-wall manifold, and the liquefied gas return manifold section within the common enclosure is a single-wall manifold.

2. The fuel injection module of claim 1.

3. the fuel injection module includes a vapor gas accumulator connected to the vapor gas outlet of the heat exchanger unit by the fuel supply line; A fuel injection module according to claim 1 or 2.

4. the liquefied gas supply manifold section being an assembly of multiple gas supply manifold sections, one supply manifold section for each cylinder of the engine; A fuel injection module according to any one of claims 1 to 3.

5. the liquefied gas return manifold section being an assembly of multiple gas return manifold sections, one return manifold section for each cylinder of the engine; A fuel injection module according to any preceding claim.

6. 1. An assembly for direct injection of a gaseous fuel into cylinders of a two-stroke multi-cylinder internal combustion piston engine, each of said cylinders comprising a fuel injection module for direct injection of a gaseous fuel into one cylinder of said engine, said fuel injection module comprising: A common enclosure, wherein the common enclosure includes a liquefied gas supply manifold section; a liquefied gas return manifold section disposed within the common enclosure in parallel with the liquefied gas supply manifold section; a liquefied gas high pressure pump unit connected to the liquefied gas supply manifold section and the liquefied gas return manifold section; a high-pressure liquefied gas outlet in the liquefied gas high-pressure pump unit; a common enclosure surrounding the The fuel injection module further comprises, external to the common enclosure: a heat exchanger unit configured to evaporate a liquefied gas and heat the evaporated gaseous gas from the liquefied gas, the heat exchanger unit having a liquefied gas inlet and a gaseous gas outlet, the liquefied gas inlet being connected to the high-pressure liquefied gas outlet of the liquefied gas high-pressure pump unit by a fuel supply line; at least one gas fuel injector connected to the heat exchanger unit; having the length of the common enclosure corresponds to the overall length of one row of cylinders of the engine; assembly.

7. The assembly has the common enclosure, the assembly being configured for a multi-cylinder two-stroke internal combustion piston engine having several cylinders arranged in a row of cylinders, the common enclosure having a length equal to the entire length of the row of cylinders; the common enclosure having an air inlet and an air outlet at opposite ends of the common enclosure; 7. The assembly of claim 6.

8. the fuel injection module further comprises a vapor gas accumulator connected to the vapor gas outlet of the heat exchanger unit by the fuel supply line; the liquefied gas supply manifold section, the liquefied gas return manifold section and the liquefied gas high pressure pump unit are disposed within the common enclosure; the heat exchanger unit and the vapor gas accumulator are disposed outside the common enclosure; 8. The assembly of claim 7.

9. The assembly includes several fuel supply lines for the cylinders of the engine, each fuel supply line including: a liquefied gas high pressure pump unit connected to the liquefied gas supply manifold section and the liquefied gas return manifold section; one heat exchanger unit configured to evaporate the liquefied gas and heat the gaseous gas; and having one gas accumulator; 7. The assembly of claim 6.

10. 6. A two-stroke internal combustion piston engine having more than one cylinder, each cylinder being provided with a fuel injection module according to any one of claims 1 to 5.

11. the common enclosure having a length from a first cylinder in a row of cylinders of the engine to a last cylinder in the row of cylinders; A two-stroke internal combustion piston engine according to claim 10.

12. the common enclosure, the liquefied gas supply manifold section, the liquefied gas return manifold section and the liquefied gas high pressure pump unit are disposed and mounted on an upper portion of the engine; A two-stroke internal combustion piston engine according to claim 10.

13. the engine having one fuel supply line for each cylinder of the engine; A two-stroke internal combustion piston engine according to claim 10 or 12.

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