Fuel supply device and engine system

Abstract

To provide a fuel supply device and an engine system which control an amount of supply of gas fuel more finely to perform output control of an engine finely. .SOLUTION: A fuel supply device 3 which supplies at least gas fuel to a predetermined target object, such as an engine 2, includes a gas fuel supply part 16 which is a gas fuel adjustment part that adjusts an amount of supply of the gas fuel and supplies it to the target object, and a temperature adjustment part 14 which adjusts a temperature of the gas fuel supplied to the gas fuel supply part 16 according to an operation state and / or an operation environment of the target object.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a fuel supply device that supplies at least gaseous fuel to a supply target such as an engine, and an engine system that includes the fuel supply device. [Background technology]

[0002] BACKGROUND ART Conventionally, engine systems equipped with gas engines or dual-fuel engines are equipped with a gas fuel supply valve such as a GAV (Gas Admission Valve) to introduce gas fuel such as hydrogen into a combustion chamber in a cylinder.

[0003] In addition, the engine system disclosed in Patent Document 1 includes at least an engine that generates power by burning gaseous fuel, a gaseous fuel supply pipe that supplies gaseous fuel to the engine, and a fuel flow rate adjustment unit that adjusts the flow rate of gaseous fuel to the gaseous fuel supply pipe. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-149336 Summary of the Invention [Problem to be solved by the invention]

[0005] In an engine system, in order to precisely control the engine output, it is necessary to adjust the opening period of the gaseous fuel supply valve and the gaseous fuel injection amount by a fuel flow rate adjusting unit. However, in an engine system, the gaseous fuel supply valve has a minimum injection period, which makes it difficult to accurately control the gaseous fuel injection amount in a low load range, and it is also difficult to appropriately control a minute engine output that is below the engine output at the minimum injection period.

[0006] An object of the present invention is to provide a fuel supply device and an engine system that can more precisely control the amount of gaseous fuel supplied and thereby perform precise control of engine output. [Means for solving the problem]

[0007] In order to solve the above problems, the fuel supply device of the present invention is a fuel supply device that supplies at least gaseous fuel to a specified supply target, and is characterized by comprising a gaseous fuel adjustment unit that adjusts the supply amount of the gaseous fuel to the supply target and supplies it to the supply target, and a temperature adjustment unit that adjusts the temperature of the gaseous fuel supplied to the gaseous fuel adjustment unit in accordance with the operating state and / or operating environment of the supply target.

[0008] Alternatively, the fuel supply device of the present invention is a fuel supply device that supplies at least gaseous fuel to a specified supply target, and is characterized by comprising a gaseous fuel adjustment unit that adjusts the supply amount of the gaseous fuel to the supply target and supplies it to the supply target, and a supply pressure adjustment unit that adjusts the supply pressure of the gaseous fuel supplied to the gaseous fuel adjustment unit in accordance with the operating state and / or operating environment of the supply target.

[0009] The engine system of the present invention is an engine system comprising the above-mentioned fuel supply device and the engine to be supplied, wherein the temperature adjustment unit has a heat exchange unit that circulates a heat exchange medium to act on the gaseous fuel, and a flow rate adjustment unit that adjusts the flow rate of the heat exchange medium, and further comprises a control device that controls the gaseous fuel adjustment unit and the flow rate adjustment unit, wherein the control device calculates a target temperature of the gaseous fuel based on a target output of the engine, and when the detected temperature of the gaseous fuel is lower than the target temperature, controls the flow rate adjustment unit so that the detected temperature becomes the target temperature, thereby raising the temperature of the gaseous fuel.

[0010] Alternatively, the engine system of the present invention is an engine system comprising the above-mentioned fuel supply device and the engine to be supplied, wherein the temperature adjustment unit has a heat exchange unit that circulates a heat exchange medium to act on the gaseous fuel, and a flow rate adjustment unit that adjusts the flow rate of the heat exchange medium, and further comprises a control device that controls the gaseous fuel adjustment unit and the flow rate adjustment unit, and the control device controls the flow rate adjustment unit to stop the flow of the heat exchange medium when the target output of the engine is equal to or greater than a predetermined output threshold.

[0011] Alternatively, the engine system of the present invention is an engine system comprising the above-mentioned fuel supply device and the engine to be supplied, wherein the temperature adjustment unit has a heat exchange unit that circulates a heat exchange medium to act on the gaseous fuel, and a cooling device that cools the heat exchange medium, and further comprises a control device that controls the gaseous fuel adjustment unit and the cooling device, and the control device controls the cooling device to operate when the target output of the engine is equal to or greater than a predetermined output threshold. [Effects of the Invention]

[0012] According to the present invention, a fuel supply device and an engine system are provided that are capable of more precisely controlling the amount of gaseous fuel supplied and thus capable of more precisely controlling the engine output. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a schematic diagram illustrating an example of an engine system including a fuel supply device according to an embodiment of the present invention. [Figure 2] 1 is a schematic diagram showing an example of an engine in an engine system equipped with a fuel supply device according to an embodiment of the present invention. [Figure 3] FIG. 2 is a schematic diagram illustrating an example of a temperature adjusting unit in the fuel supply device according to the embodiment of the present invention. [Figure 4] FIG. 10 is a schematic diagram showing another example of a temperature adjusting unit in the fuel supply device according to the embodiment of the present invention. [Figure 5]4 is a flowchart showing an example of the operation of the fuel supply device according to the embodiment of the present invention. [Figure 6] 5 is a time chart showing an example of operation when the fuel supply device according to the embodiment of the present invention is changed from a diesel mode to a gas mode. [Figure 7] 10 is a graph showing an example of a map showing the relationship between the engine load and the target supply pressure of gaseous fuel in a fuel supply device according to a modified example of the present invention. [Figure 8] 10 is a graph showing an example of a map showing the relationship between the engine load and the target supply pressure of gaseous fuel according to the mixed combustion ratio in a fuel supply device according to a modified example of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0014] An engine system 1 according to an embodiment of the present invention will be described with reference to the drawings. As shown in Fig. 1, the engine system 1 includes an engine 2 that runs on at least gaseous fuel, and a fuel supply device 3 that supplies gaseous fuel to the engine 2, which is the fuel supply target. The engine 2 can be a propulsion engine (main engine) for a ship or the like, or a power generation engine (auxiliary engine). In this embodiment, an example will be described in which the engine system 1 includes the engine 2 that is a power generation engine (auxiliary engine), and the engine 2 and a generator 4 are connected to drive the generator 4 with the output of the engine 2.

[0015] In particular, this embodiment will describe an example in which the engine 2 is configured as a dual-fuel engine that is driven by feeding at least one of gaseous fuel such as hydrogen and liquid fuel such as diesel or heavy oil into the combustion chamber 25 of the engine 2. The engine system 1 operates in one of three combustion modes: a gas mode that uses only gaseous fuel as fuel for the engine 2, a diesel mode that uses only liquid fuel, and a multi-fuel mode that uses both gaseous fuel and liquid fuel.

[0016] The engine system 1 includes a liquid fuel supply unit 5 that supplies liquid fuel to the engine 2. The liquid fuel supply unit 5 is connected to a liquid fuel tank (not shown) via a liquid fuel supply passage (not shown), and is configured to input (inject) the liquid fuel supplied through the liquid fuel supply passage into a combustion chamber 25 of the engine 2.

[0017] The fuel supply device 3 includes a liquefied gas fuel tank 10 (gaseous fuel storage section), a gaseous fuel supply passage 11, a vaporizer 12, a pressure regulator 13, a temperature regulator 14, a chamber 15, a gaseous fuel supply section 16 (gaseous fuel regulator), and a control device 17. Details of each section of the fuel supply device 3 will be described later.

[0018] First, the engine 2 will be described.

[0019] The engine 2 is configured with a cylinder block 20 and a plurality of cylinders 21. As shown in Fig. 2, each cylinder 21 is configured with a cylinder 22, a piston 23, and a cylinder head 24, and defines a combustion chamber 25 therein. A gas fuel supply unit 16 and a liquid fuel supply unit 5 are provided for each cylinder 21.

[0020] The cylinder 22 is formed, for example, in a cylindrical shape within the cylinder block 20, and the piston 23 is slidably housed within the cylinder 22. The cylinder head 24 is attached to the upper side of the cylinder 22, and a combustion chamber 25 is formed inside the cylinder 22 and the cylinder head 24.

[0021] The cylinder head 24 has an intake port 27 connected to an intake passage 26 that introduces air, and an exhaust port 29 connected to an exhaust passage 28 that discharges exhaust gas. The intake port 27 and the exhaust port 29 communicate with the combustion chamber 25, and the cylinder head 24 is equipped with an intake valve 30 and an exhaust valve 31 that open and close the intake port 27 and the exhaust port 29 to and from the combustion chamber 25, respectively.

[0022] 2 shows an example in which the intake passage 26 and the intake port 27 are directly connected, or in another example, the intake passage 26 and the intake port 27 may be connected via an intake manifold provided between the intake passage 26 and the engine 2. Also, while FIG. 2 shows an example in which the exhaust passage 28 and the exhaust port 29 are directly connected, or in another example, the exhaust passage 28 and the exhaust port 29 may be connected via an exhaust manifold provided between the exhaust passage 28 and the engine 2.

[0023] The cylinder head 24 is provided with a gaseous fuel supply unit 16 for supplying gaseous fuel to the inside of an intake port 27, and a liquid fuel supply unit 5 for supplying liquid fuel to the combustion chamber 25. The intake port 27 introduces a mixture of gaseous fuel supplied from the gaseous fuel supply unit 16 and air supplied from an intake passage 26 into the combustion chamber 25. The exhaust port 29 discharges exhaust gas generated in the combustion chamber 25 into an exhaust passage 28.

[0024] In each cylinder 21, a small amount of pilot fuel (liquid fuel) is injected into the combustion chamber 25 by the liquid fuel supply unit 5 at an appropriate timing when the air-fuel mixture introduced from the intake port 27 is compressed by the sliding of the piston 23, thereby igniting the gaseous fuel in the air-fuel mixture. The piston 23 reciprocates within the cylinder 21 by the thrust obtained from the explosion occurring in the combustion chamber 25.

[0025] Each cylinder 22 of the multiple cylinders 21 is connected to a crankcase 32, and a crankshaft 33 is rotatably supported by the crankcase 32. The piston 23 of each cylinder 21 is connected to the crankshaft 33 via a connecting rod 34, and the reciprocating motion of the piston 23 is converted into the rotational motion of the crankshaft 33 via the connecting rod 34.

[0026] Next, each part of the fuel supply device 3 will be described.

[0027] The liquefied gas fuel tank 10 stores liquefied gas fuel, for example, liquid hydrogen fuel, which is hydrogen fuel in a liquid state.

[0028] The gaseous fuel supply passage 11 connects the liquefied gaseous fuel tank 10 and the gaseous fuel supply unit 16, and allows the gaseous fuel to flow from the liquefied gaseous fuel tank 10 to the gaseous fuel supply unit 16. In the gaseous fuel supply passage 11, a vaporizer 12, a pressure regulator 13 (supply pressure regulator), a temperature regulator 14, and a chamber 15 are provided in this order between the liquefied gaseous fuel tank 10 and the gaseous fuel supply unit 16.

[0029] The gaseous fuel supply passage 11 is configured as a multi-layer pipe (for example, a double pipe) between the chamber 15 and the gaseous fuel supply unit 16, and is configured to maintain the pressure (supply pressure) of the gaseous fuel adjusted by the pressure regulator 13 and the temperature of the gaseous fuel adjusted by the temperature adjuster 14. In the gaseous fuel supply passage 11 of the multi-layer pipe, the gaseous fuel is circulated through the innermost pipe, and air is circulated between the innermost pipe and an outer pipe covering the innermost pipe.

[0030] The gaseous fuel supply passage 11 has a common passage 11a that distributes gaseous fuel commonly to the plurality of gaseous fuel supply units 16 of the plurality of cylinders 21, and a plurality of branch passages 11b that branch off from the common passage 11a and distribute gaseous fuel to each of the plurality of gaseous fuel supply units 16. A carburetor 12, a pressure regulator 13, a temperature regulator 14, and a chamber 15 are provided in this order in the common passage 11a.

[0031] The vaporizer 12 vaporizes the liquid gas fuel supplied from the liquefied gas fuel tank 10 , and supplies the vaporized gas fuel to the pressure regulator 13 via the gas fuel supply passage 11 .

[0032] The pressure regulating device 13 adjusts the supply pressure of the gaseous fuel supplied via the gaseous fuel supply unit 16, and supplies the gaseous fuel with the adjusted supply pressure to the temperature regulating unit 14 via the gaseous fuel supply passage 11. The pressure regulating device 13 is configured, for example, by a gas valve unit (GVU) having a plurality of valves.

[0033] 1 , the pressure regulating device 13 is configured to include a first shutoff valve 36 on the upstream side in the supply direction of the gaseous fuel in the gaseous fuel supply passage 11, a second shutoff valve 37 on the downstream side, and an open valve 39 in an open passage 38 branching from the gaseous fuel supply passage 11 between the first shutoff valve 36 and the second shutoff valve 37. The pressure regulating device 13 controls the supply pressure (flow rate per unit time) of the gaseous fuel flowing downstream of the pressure regulating device 13 by controlling the apertures of the first shutoff valve 36 and the second shutoff valve 37 in response to a control signal from the control device 17. Furthermore, the pressure regulating device 13 normally closes the open valve 39, but can also control a purge function of the gaseous fuel in the gaseous fuel supply passage 11 by closing the first shutoff valve 36 to shut it off and opening the open valve 39 in response to a control signal from the control device 17.

[0034] The temperature adjustment unit 14 adjusts the temperature of the gaseous fuel supplied via the gaseous fuel supply unit 16, and supplies the temperature-adjusted gaseous fuel to the chamber 15 via the gaseous fuel supply passage 11. The temperature adjustment unit 14 is provided separately from the vaporizer 12, which is provided to bring the liquefied gaseous fuel stored in the liquefied gaseous fuel tank 10 into a gaseous state, and adjusts the temperature of the gaseous fuel in the gaseous state. For example, as shown in FIG. 3 , the temperature adjustment unit 14 has a first heat exchanger 40 (heat exchange unit) and a first flow rate adjustment unit 41 (flow rate adjustment unit), and further has a second heat exchanger 42 and a second flow rate adjustment unit 43.

[0035] The first heat exchanger 40 circulates a heat exchange medium such as an ethylene glycol aqueous solution and also circulates gaseous fuel, and adjusts the temperature of the gaseous fuel by causing the heat exchange medium to act on the gaseous fuel to perform heat exchange. The first flow rate adjustment unit 41 is composed of a pump or the like, and adjusts the flow rate of the heat exchange medium circulating through the first heat exchanger 40 in response to a control signal from the control device 17, thereby adjusting the temperature of the gaseous fuel that is exchanging heat with the heat exchange medium.

[0036] The second heat exchanger 42 circulates an auxiliary medium such as engine coolant or engine oil, as well as gaseous fuel, and adjusts the temperature of the heat exchange medium by causing the auxiliary medium to act on the heat exchange medium to perform heat exchange. The second flow rate adjustment unit 43 is composed of a pump or the like, and adjusts the flow rate of the auxiliary medium circulating through the second heat exchanger 42 in response to a control signal from the control device 17, thereby adjusting the temperature of the heat exchange medium that exchanges heat with the auxiliary medium.

[0037] That is, the temperature of the gaseous fuel is precisely adjusted by using the first heat exchanger 40 and the second heat exchanger 42. The first flow rate adjuster 41 and the second flow rate adjuster 43 can stop heat exchange by stopping the flow of the heat exchange medium and the auxiliary medium.

[0038] 4, the temperature adjustment unit 14 may include a cooling device 44 in addition to the first heat exchanger 40, the first flow rate adjustment unit 41, and the second heat exchanger 42 and the second flow rate adjustment unit 43. The heat exchange medium that adjusts the temperature of the gaseous fuel in the first heat exchanger 40 is temperature adjusted by the auxiliary medium in the second heat exchanger 42, and the cooling device 44 is provided in the flow path of the heat exchange medium and is operated by electricity to lower the temperature of the heat exchange medium.

[0039] The chamber 15 is provided between the temperature adjustment unit 14 and the gaseous fuel supply unit 16 in the supply direction of the gaseous fuel in the gaseous fuel supply passage 11. The chamber 15 accumulates a predetermined amount or more of gaseous fuel whose supply pressure is adjusted by the pressure adjustment device 13 and whose temperature is adjusted by the temperature adjustment unit 14, and by pressurizing the gaseous fuel inside the gaseous fuel supply passage 11 toward the downstream side of the chamber 15, the adjusted supply pressure and temperature of the gaseous fuel are maintained downstream of the chamber 15 regardless of the supply of gaseous fuel from the gaseous fuel supply unit 16.

[0040] As described above, the gaseous fuel supply unit 16 is provided in the cylinder head 24 of each cylinder 21 of the engine 2, and supplies gaseous fuel to the inside of the intake port 27 in response to a control signal from the control device 17. For example, the gaseous fuel supply unit 16 is configured with an admission valve (GAV: Gas Admission Valve) that injects gaseous fuel. The gaseous fuel supply unit 16 can adjust the amount of gaseous fuel supplied by adjusting the valve opening period in response to the control signal from the control device 17.

[0041] The control device 17 is a computer such as an ECU (Engine Control Unit) that controls the operation of the engine 2, and is equipped with a CPU, ROM, RAM, etc., and is configured to control each part of the engine 2. The control device 17 stores various programs for controlling the engine 2, and controls the engine 2 by reading and executing the programs. In particular, the control device 17 controls the pressure regulator 13 and the temperature adjustment unit 14 according to the operating state of the engine 2, such as the engine output (engine speed), or the operating environment, such as the ambient temperature of the engine 2 and the fuel supply device 3. The control device 17 may be provided on the engine 2 side, or on the fuel supply device 3 side.

[0042] In the engine system 1, the target output of the engine 2 is determined according to the operating state (generator load) of the generator 4. The amount of gaseous fuel required to be supplied to the combustion chamber 25 of each cylinder 21 is determined according to the target output, and therefore the valve open period and supply pressure of the gaseous fuel supplied to the combustion chamber 25 by the gaseous fuel supply unit 16 are determined according to the target output. Therefore, the control device 17 controls the pressure regulating device 13 according to the target output, thereby adjusting the supply pressure of the gaseous fuel to a supply pressure (or supply pressure range) corresponding to the target output, i.e., a target supply pressure (or target supply pressure range). The control device 17 may set the valve open period of the gaseous fuel supply unit 16 according to the previously set target supply pressure (or target supply pressure range), or may set the target supply pressure (or target supply pressure range) according to the previously set valve open period of the gaseous fuel supply unit 16.

[0043] Meanwhile, in the engine system 1, a lower limit (minimum valve opening period) and an upper limit (maximum valve opening period) of the valve opening period of the gaseous fuel of the gaseous fuel supply unit 16 and a lower limit (minimum supply pressure) and an upper limit (maximum supply pressure) of the supply pressure of the gaseous fuel of the pressure regulator 13 are determined, but the control device 17 cannot set the valve opening period or the supply pressure outside the range of the lower and upper limits. Therefore, even if the target output (generator load) of the engine 2 is low (in the low load range) and the valve opening period of the gaseous fuel supply unit 16 calculated according to the target output is less than the minimum valve opening period, the control device 17 sets the valve opening period of the gaseous fuel supply unit 16 to be equal to or greater than the minimum valve opening period, so that the actual output of the engine 2 may exceed the target output.

[0044] However, according to this embodiment, the control device 17 adjusts the temperature of the gaseous fuel supplied to the gaseous fuel supply unit 16 based on the gas state equation, thereby adjusting the energy density (supply pressure) of the gaseous fuel supplied to the gaseous fuel supply unit 16 and thereby adjusting the supply amount, regardless of the supply pressure set by the pressure regulator 13. Note that the temperature of the gaseous fuel supplied to the gaseous fuel supply unit 16 is not limited to a specific target temperature, and as long as it is within a predetermined target temperature range, the gaseous fuel can be gaseous fuel with a target energy density, i.e., gaseous fuel with a target supply pressure (or target supply pressure range).

[0045] Specifically, in order to obtain the target temperature of the gaseous fuel corresponding to the target output of the engine 2, the control device 17 may predetermine and store a map or a formula indicating the relationship between the target output of the engine 2 and the target temperature (or target temperature range) of the gaseous fuel. The control device 17 calculates the target temperature of the gaseous fuel according to the map or formula based on the target output. The target temperature may be determined solely by the target output of the engine 2. Alternatively, a map or a formula may be predetermine to specify the target temperature according to the discharge pressure of the carburetor 12 or the reference injection period of the gaseous fuel supply unit 16 in addition to or instead of the target output. The control device 17 may store a map or a formula indicating the relationship between the target output of the engine 2 and the target temperature of the gaseous fuel for each operating environment (e.g., ambient temperature and humidity), and may use the map or formula corresponding to the detected operating environment.

[0046] Furthermore, the control device 17 detects the actual temperature (detected temperature) of the gaseous fuel supplied to the gaseous fuel supply unit 16, compares the detected temperature with a target temperature (or target temperature range), and if the detected temperature is not the target temperature (or is outside the target temperature range), controls the temperature of the gaseous fuel by the temperature adjustment unit 14 so that the detected temperature becomes the target temperature. Note that the engine system 1 is provided with a temperature sensor (not shown) in any of the temperature adjustment unit 14, the chamber 15, the gaseous fuel supply passage 11, or the gaseous fuel supply unit 16 in order to detect the temperature of the gaseous fuel supplied to the gaseous fuel supply unit 16.

[0047] Furthermore, when the gaseous fuel reaches the target temperature, the control device 17 controls the pressure regulator 13 to adjust the supply pressure of the gaseous fuel, taking into account the supply pressure fluctuation of the gaseous fuel from the gaseous fuel supply unit 16, which fluctuates depending on the target temperature, relative to the supply pressure of the gaseous fuel from the pressure regulator 13.

[0048] For example, when the target output of the engine 2 is low (in the low load range) and the detected temperature is lower than the target temperature, the control device 17 controls the first flow rate adjustment unit 41 of the temperature adjustment unit 14 to raise the temperature of the gaseous fuel so that the detected temperature becomes the target temperature. Also, when the target output of the engine 2 is equal to or higher than a predetermined output threshold (in the high load range), the control device 17 controls the temperature adjustment unit 14 so as not to raise the temperature of the gaseous fuel regardless of the target temperature according to the target output, for example, controls the first flow rate adjustment unit 41 to stop the flow of the heat exchange medium in the temperature adjustment unit 14.

[0049] Therefore, the control device 17 controls not only the supply pressure of the gaseous fuel by the pressure regulator 13 but also the temperature of the gaseous fuel by the temperature regulator 14, thereby more precisely adjusting the energy density (supply pressure) of the gaseous fuel supplied to the gaseous fuel supply unit 16 and thus more precisely adjusting the supply amount. For example, even if the valve-opening period of the gaseous fuel supply unit 16 calculated according to the target output of the engine 2 is shorter than the minimum valve-opening period, the control device 17 can adjust the actual output of the engine 2 to the target output by lowering the energy density (supply pressure) of the gaseous fuel by raising the temperature of the gaseous fuel by the temperature regulator 14, even if the valve-opening period of the gaseous fuel supply unit 16 is set to be equal to or longer than the minimum valve-opening period. In other words, when the valve-opening period (target valve-opening period) of the gaseous fuel supply unit 16 calculated according to the target output of the engine 2 is shorter than the minimum valve-opening period, the control device 17 raises the temperature of the gaseous fuel by the temperature regulator 14 so that the valve-opening period of the gaseous fuel supply unit 16 that is actually controlled is equal to or longer than the minimum valve-opening period.

[0050] Next, an example of the operation of the fuel supply device 3 of the engine system 1 of this embodiment will be described with reference to the flowchart of FIG.

[0051] First, the control device 17 acquires various sensor values ​​and various setting values ​​related to the operating environment, such as the operating state of the engine 2 or the ambient temperature of the engine 2 and the fuel supply device 3, as control parameters for the fuel supply device 3 (step S1). For example, the control device 17 acquires the combustion mode, the mixed combustion ratio (ratio of gaseous fuel), the detected temperature of the gaseous fuel, and the target output of the engine 2 or the generator load of the generator 4 as control parameters related to the operating state. The control device 17 also acquires the ambient temperature and humidity of the engine 2 and the fuel supply device 3 as control parameters related to the operating environment.

[0052] The control device 17 calculates a target temperature (or a target temperature range) of the gaseous fuel to be supplied to the gaseous fuel supply unit 16 based on the acquired control parameters, and acquires the target temperature based on, for example, a map showing the relationship between the target output of the engine 2 and the target temperature of the gaseous fuel. Then, the control device 17 compares the detected temperature of the gaseous fuel with the target temperature (step S2).

[0053] If the detected temperature of the gaseous fuel is the target temperature (or within the target temperature range) (step S2: Yes), the control device 17 maintains the current control state of the temperature adjustment unit 14 (step S3) and proceeds to control the pressure adjustment device 13 (step S4).

[0054] On the other hand, if the detected temperature of the gaseous fuel is not the target temperature (or is outside the target temperature range) (step S2: No), the control device 17 calculates a control amount for the temperature adjustment unit 14 (step S5), and controls the temperature adjustment of the gaseous fuel by the temperature adjustment unit 14 based on the control amount (step S6). For example, the control device 17 calculates the flow rate of the heat exchange medium by the first flow rate adjustment unit 41 and the flow rate of the auxiliary medium by the second flow rate adjustment unit 43 as control amounts based on the difference between the detected temperature and the target temperature, and controls the first flow rate adjustment unit 41 and the second flow rate adjustment unit 43.

[0055] In parallel with the temperature adjustment by the temperature adjustment unit 14, the control device 17 redetects the detected temperature of the gaseous fuel and compares the detected temperature of the gaseous fuel with the target temperature (step S7). If the redetected detected temperature of the gaseous fuel is not the target temperature (step S7: No), the control device 17 continues the temperature adjustment by the temperature adjustment unit 14 (step S6).

[0056] On the other hand, if the re-detected temperature of the gaseous fuel is the target temperature (step S7: Yes), the control device 17 controls the temperature adjustment unit 14 to maintain the current temperature of the gaseous fuel, and proceeds to control the pressure adjustment device 13 (step S4).

[0057] In the control of the pressure regulating device 13 (step S4), the control device 17 adjusts the supply pressure of the gaseous fuel to a target supply pressure corresponding to the target output. Note that when the temperature of the gaseous fuel is adjusted by the temperature adjusting unit 14, the control device 17 controls the pressure regulating device 13 to adjust the supply pressure of the gaseous fuel so that the supply pressure of the gaseous fuel supplied to the gaseous fuel supply unit 16 becomes the target supply pressure corresponding to the target output, taking into consideration that the supply pressure of the gaseous fuel fluctuates due to the temperature adjustment by the temperature adjusting unit 14.

[0058] Furthermore, the control device 17 calculates control variables such as the valve opening period and injection pressure of the gas fuel supply unit 16 and the liquid fuel supply unit 5 based on the required supply amount of gas fuel in the combustion chamber 25 based on the target output of the engine 2 and the supply pressure of the gas fuel of the gas fuel supply unit 16 (step S8).

[0059] Then, the control device 17 controls the gas fuel supply unit 16 and the liquid fuel supply unit 5 based on the calculated control amount, thereby supplying the required amount of gas fuel or liquid fuel to the combustion chamber 25 and driving the engine 2 (step S9).

[0060] In the above-described operation example, the temperature of the gaseous fuel is redetected and compared with the target temperature in step S7, which indicates the transition condition for transitioning to control by the pressure regulator 13 after temperature adjustment by the temperature adjuster 14, but the present invention is not limited to this example. As another example, the control device 17 may determine that the transition condition is satisfied when a timer detects that a predetermined time has elapsed, instead of the transition condition described above.

[0061] Alternatively, the control device 17 may skip the step of determining the transition conditions, and after activating the temperature adjustment unit 14, proceed directly to the gas fuel supply pressure control (steps S8 and S9). Note that if it becomes necessary to adjust the temperature of the gas fuel while operating in the gas mode, for example, if an instruction is input to change the engine 2 from operating at medium power to operating at low power, waiting for the target temperature to be reached before proceeding to the next step may result in a decrease in responsiveness to the change in engine power. Therefore, the control device 17 may skip the step of determining the transition conditions when priority is given to responsiveness to the change in engine power.

[0062] An example of the operation of the fuel supply device 3 when the engine system 1 of this embodiment is changed from the diesel mode to the gas mode (or the multi-fuel mode) will be described with reference to the time chart of FIG.

[0063] Figure 6 shows the changes over time in the target output of engine 2, the set value of the fuel combustion ratio of the fuel fed to combustion chamber 25, the proportion of liquid fuel, the temperature of the gaseous fuel supplied to gaseous fuel supply unit 16, the valve opening period of gaseous fuel supply unit 16, the flow rate of gaseous fuel supplied from gaseous fuel supply unit 16, and the actual output of engine 2.

[0064] In this operation example, while the combustion mode is in the diesel mode, the actual output of the engine 2 is equal to the target output, and at time t1 the combustion mode is changed from the diesel mode to the gas mode (or multi-fuel mode).

[0065] In response to this change in combustion mode, the control device 17 sets the valve opening period of the gaseous fuel supply unit 16 to the minimum valve opening period and sets the flow rate of the gaseous fuel of the gaseous fuel supply unit 16 to a predetermined flow rate, thereby controlling the temperature adjustment unit 14 to raise the temperature of the gaseous fuel supplied to the gaseous fuel supply unit 16, so that the actual output of the engine 2 becomes higher than the target output.

[0066] By increasing the temperature of the gaseous fuel as described above, the control device 17 can reduce the flow rate of the gaseous fuel supplied by the gaseous fuel supply unit 16 during the minimum valve opening period compared to when the temperature of the gaseous fuel is not increased. This allows the actual output of the engine 2 to be reduced compared to when the temperature of the gaseous fuel is not increased. Specifically, the actual output of the engine 2 can be kept at the target output. In FIG. 6, the solid lines indicate the state in which the temperature of the gaseous fuel is adjusted, and the dashed-dotted lines indicate the state in which the temperature of the gaseous fuel is not adjusted, with respect to the temperature and flow rate of the gaseous fuel and the actual output of the engine 2. If the temperature of the gaseous fuel is not adjusted, the actual output of the engine 2 will increase until all the liquid fuel is throttled out, exceeding the target output as shown by the dashed-dotted line. However, in this embodiment, adjusting the temperature of the gaseous fuel can prevent the actual output from exceeding the target output.

[0067] The control device 17 may control the temperature of the gaseous fuel to gradually increase, and in this case, the flow rate of the gaseous fuel from the gaseous fuel supply unit 16 may be controlled to gradually decrease from a predetermined flow rate, thereby gradually reducing the actual output of the engine 2. The control device 17 may also control the liquid fuel supply unit 5 and the gaseous fuel supply unit 16 so that the proportion of liquid fuel gradually decreases as the temperature of the gaseous fuel increases. When the temperature of the gaseous fuel reaches a target temperature, the control device 17 stops the temperature adjustment by the temperature adjustment unit 14, and thereby the actual output of the engine 2 is reduced to and maintained at a constant output, for example, the target output.

[0068] As described above, according to this embodiment, the fuel supply device 3 that supplies at least gaseous fuel to a predetermined supply target such as the engine 2 includes the gaseous fuel supply unit 16, which is a gaseous fuel adjustment unit that adjusts the amount of gaseous fuel supplied to the supply target, and the temperature adjustment unit 14 that adjusts the temperature of the gaseous fuel supplied to the gaseous fuel supply unit 16 according to the operating state and / or operating environment of the supply target.

[0069] As a result, the fuel supply device 3 adjusts the temperature of the gaseous fuel supplied to the gaseous fuel supply unit 16, thereby more precisely controlling the amount of gaseous fuel supplied from the gaseous fuel supply unit 16 and enabling precise operation control of the target to be supplied, for example, precise control of the output of the engine 2. Furthermore, in the case of gaseous fuel in a gaseous phase, a larger heat transfer area is required compared to temperature adjustment of gaseous fuel in a liquid phase, but providing the temperature adjustment unit 14 upstream of the gaseous fuel supply unit 16 makes it easier to ensure the required heat transfer area.

[0070] Furthermore, according to this embodiment, the fuel supply device 3 is provided with a pressure regulating device 13 that adjusts the supply pressure of the gaseous fuel, and the temperature adjusting unit 14 is provided between the pressure regulating device 13 and the gaseous fuel supply unit 16 in the supply direction of the gaseous fuel.

[0071] As a result, in the fuel supply device 3, the temperature adjustment unit 14 can obtain high heat exchange efficiency and perform more appropriate temperature adjustment by exchanging heat with the gaseous fuel whose flow rate has increased after passing through the pressure reducing valve of the pressure regulating device 13, etc. Therefore, the amount of gaseous fuel supplied from the gaseous fuel supply unit 16 can be controlled more precisely, and the operation of the supply target, for example, the output of the engine 2, can be controlled more precisely.

[0072] Furthermore, according to this embodiment, the fuel supply device 3 includes a gas fuel supply passage 11 that connects the liquefied gas fuel tank 10, which is a gas fuel storage section that stores gas fuel, to the gas fuel supply section 16 and circulates the gas fuel, and the pressure adjustment device 13 and the temperature adjustment section 14 are provided in the gas fuel supply passage 11.

[0073] This allows the fuel supply device 3 to appropriately adjust the supply pressure and temperature of the gaseous fuel supplied to the gaseous fuel supply unit 16.

[0074] Furthermore, according to this embodiment, the fuel supply device 3 includes the chamber 15, which is provided between the temperature adjustment unit 14 and the gaseous fuel supply unit 16 and stores the gaseous fuel whose temperature has been adjusted.

[0075] As a result, by providing the chamber 15 after the temperature adjustment unit 14, the fuel supply device 3 can stably supply temperature-adjusted gaseous fuel to the engine 2 regardless of the supply of gaseous fuel by the gaseous fuel supply unit 16. Furthermore, by providing the chamber 15, various valves such as the first shut-off valve 36 and the second shut-off valve 37 provided in the pressure regulating device 13 can be simplified.

[0076] Furthermore, according to this embodiment, the fuel supply device 3 supplies fuel to an engine 2 having a plurality of cylinders 21, the gaseous fuel supply unit 16 is a gaseous fuel supply valve provided in each of the plurality of cylinders 21, the gaseous fuel supply passage 11 has a common passage 11a that circulates gaseous fuel commonly to the plurality of cylinders 21, and the temperature adjustment unit 14 is provided in the common passage 11a.

[0077] This allows the fuel supply device 3 to be simplified compared to a case where a mechanism for adjusting the temperature of the gaseous fuel is provided for each gaseous fuel supply valve.

[0078] Furthermore, according to this embodiment, in the engine system 1 equipped with the above-mentioned fuel supply device 3 and the engine 2, the temperature adjustment unit 14 has a first heat exchanger 40 which is a heat exchange unit that circulates a heat exchange medium to act on the gaseous fuel, and a first flow rate adjustment unit 41 that adjusts the flow rate of the heat exchange medium, and further includes a control device 17 that controls the gaseous fuel supply unit 16 and the first flow rate adjustment unit 41, and the control device 17 calculates a target temperature of the gaseous fuel based on the target output of the engine 2, and if the detected temperature of the gaseous fuel is lower than the target temperature, controls the first flow rate adjustment unit 41 to raise the temperature of the gaseous fuel so that the detected temperature becomes the target temperature.

[0079] In the engine system 1, even if the required valve opening period of the gaseous fuel supply unit 16 calculated based on the target output of the engine 2 is shorter than the minimum valve opening period, the gaseous fuel supply unit 16 is operated with the minimum valve opening period to supply the gaseous fuel, so that more gaseous fuel than planned is supplied, and the actual output of the engine 2 may be higher than the target output. In contrast, in the present embodiment, the temperature of the gaseous fuel is raised to a target temperature based on the target output of the engine 2, thereby lowering the energy density of the gaseous fuel supplied from the gaseous fuel supply unit 16. Therefore, even if the required valve opening period is shorter than the minimum valve opening period, the actual output of the engine 2 can be controlled to be the target output even if the gaseous fuel supply unit 16 is operated with a valve opening period equal to or longer than the minimum valve opening period.

[0080] Furthermore, according to this embodiment, in the engine system 1 including the above-mentioned fuel supply device 3 and the engine 2, the temperature adjustment unit 14 has a first heat exchanger 40 which is a heat exchange unit that circulates a heat exchange medium to act on the gaseous fuel, and a first flow rate adjustment unit 41 that adjusts the flow rate of the heat exchange medium, and further includes a control device 17 that controls the gaseous fuel supply unit 16 and the first flow rate adjustment unit 41, and the control device 17 controls the first flow rate adjustment unit 41 to stop the flow of the heat exchange medium when the target output of the engine 2 is equal to or greater than a predetermined output threshold.

[0081] Alternatively, in the engine system 1, the temperature adjustment unit 14 has a first heat exchanger 40, which is a heat exchange unit that circulates a heat exchange medium to act on the gaseous fuel, and a cooling device 44 that cools the heat exchange medium, and further includes a control device 17 that controls the gaseous fuel supply unit 16 and the cooling device 44, and the control device 17 controls the cooling device 44 to operate when the target output of the engine 2 is equal to or greater than a predetermined output threshold.

[0082] As a result, when the engine 2 is in a high load range, the engine system 1 can supply more gaseous fuel to the engine 2 and obtain higher output by lowering the temperature of the gaseous fuel supplied to the gaseous fuel supply unit 16.

[0083] As another example, in order to improve the real-timeness of the temperature of the gaseous fuel in the gaseous fuel supply unit 16 relative to the temperature adjustment of the gaseous fuel in the temperature adjustment unit 14, another passage may be provided connecting the temperature adjustment unit 14 to the gaseous fuel supply unit 16 without passing through the chamber 15. Furthermore, in order to improve the real-timeness of the temperature of the gaseous fuel waiting between the chamber 15 and the gaseous fuel supply unit 16, the gaseous fuel whose temperature has been adjusted by the temperature adjustment unit 14 may be circulated.

[0084] In the above-described embodiment, the engine system 1 (control device 17) adjusts the supply pressure of the gaseous fuel using the pressure regulating device 13 so that it becomes a target supply pressure (or target supply pressure range) corresponding to the target output of the engine 2, and also adjusts the supply amount of gaseous fuel by controlling the temperature of the gaseous fuel using the temperature adjusting unit 14 so that the detected temperature of the gaseous fuel supplied to the gaseous fuel supply unit 16 becomes a target temperature corresponding to the operating state of the engine 2 (e.g., target output) or the operating environment of the engine 2 or the fuel supply device 3, but the present invention is not limited to this example.

[0085] For example, in a modified example of the present invention, the engine system 1 (control device 17) may adjust the supply pressure of the gaseous fuel using the pressure regulating device 13 and adjust the valve opening period using the gaseous fuel supply unit 16, thereby adjusting the supply amount of gaseous fuel, without controlling the temperature of the gaseous fuel, depending on the operating state of the engine 2 and / or the operating environment of the engine 2 and the fuel supply device 3.

[0086] Specifically, in this modified example, as shown in FIG. 7, when the engine 2 is operating normally, the control device 17 adjusts the supply pressure of the gaseous fuel supplied from the fuel supply device 3 to the gaseous fuel supply unit 16 by the pressure regulating device 13 so that it is a constant value regardless of the operating state and / or operating environment.

[0087] On the other hand, when the engine 2 is operated in a low load range, the control device 17 adjusts the supply pressure of the gaseous fuel to a supply pressure according to the operating state and / or operating environment using the pressure regulator 13. In this case, the control device 17 detects the actual load on the engine 2, and determines that the engine is in a low load range when the actual load is equal to or less than a predetermined load threshold (for example, 20%).

[0088] The control device 17 may store in advance a map or a formula indicating the relationship between the load of the engine 2 and the target supply pressure (or target supply pressure range) of the gaseous fuel. The control device 17 may store a map or a formula indicating the relationship between the load of the engine 2 and the target supply pressure of the gaseous fuel for each operating environment (e.g., ambient temperature and humidity), and may use the map or formula corresponding to the detected operating environment. The control device 17 then obtains the target supply pressure corresponding to the detected actual load of the engine 2 based on the map or formula, and adjusts the supply pressure of the gaseous fuel to the target supply pressure using the pressure regulator 13.

[0089] At this time, the control device 17 controls the pressure regulator 13 to change the supply pressure of the gaseous fuel at a pressure change rate according to the operation mode of the engine 2. Specifically, when the detected supply pressure of the gaseous fuel is higher than a target supply pressure corresponding to the actual load of the engine 2, the control device 17 adjusts the supply pressure of the gaseous fuel to decrease. Furthermore, when the detected supply pressure of the gaseous fuel is lower than the target supply pressure corresponding to the actual load of the engine 2, the control device 17 adjusts the supply pressure of the gaseous fuel to increase.

[0090] The control device 17 sets the pressure change rate faster when the operation mode of the engine 2 is in the notch down mode or emergency response mode than when the operation mode is in the normal mode, for example, setting the pressure change rate to ±1 MPa / min when in the normal mode, and setting the pressure change rate to ±15 MPa / sec when in the notch down mode or emergency response mode. Note that since the target supply pressure is the upper limit or lower limit, the control device 17 does not adjust the supply pressure to exceed the target supply pressure.

[0091] FIG. 7 shows a map illustrating the relationship between the load of engine 2 and the target supply pressure of gaseous fuel when the combustion mode of engine 2 is gas mode, and FIG. 8 shows a map illustrating the relationship between the load of engine 2 and the target supply pressure of gaseous fuel according to the mixed combustion ratio when the combustion mode of engine 2 is mixed combustion mode.

[0092] In the dual-combustion mode, when the dual-combustion ratio is low, the gaseous fuel supply unit 16 needs to perform a small injection of gaseous fuel to reduce the amount of gaseous fuel supplied, but the response speed of the gaseous fuel supply unit 16 to the small injection control may not be enough to completely throttle the amount of gaseous fuel supplied. Therefore, it is preferable that the control device 17 prepares in advance a map or formula showing the relationship between the load of the engine 2 and the target supply pressure of gaseous fuel so that the load threshold is increased as the dual-combustion ratio is lower, as shown in Figure 8.

[0093] Furthermore, the present invention can be modified as appropriate within the scope that does not contradict the gist or concept of the invention that can be read from the claims and the entire specification, and fuel supply devices and engine systems that involve such modifications are also included in the technical concept of the present invention.

[0094] [Appendix to the invention] The following is a summary of the invention extracted from the above-described embodiment. Note that the configurations and processing functions described in the following supplementary notes can be selected and combined as desired.

[0095] <Appendix 1> A fuel supply device that supplies at least gaseous fuel to a predetermined supply target, a gaseous fuel adjusting unit that adjusts a supply amount of the gaseous fuel to the supply target and supplies the adjusted amount; a temperature adjusting unit that adjusts the temperature of the gaseous fuel to be supplied to the gaseous fuel adjusting unit in accordance with an operating state and / or an operating environment of the target to be supplied.

[0096] <Appendix 2> A fuel supply device that supplies at least gaseous fuel to a predetermined supply target, a gaseous fuel adjusting unit that adjusts the supply amount of the gaseous fuel to the supply target and supplies the adjusted amount; a supply pressure adjusting unit that adjusts the supply pressure of the gaseous fuel supplied to the gaseous fuel adjusting unit in accordance with an operating state and / or operating environment of the supply target.

[0097] <Appendix 3> a pressure regulating device that adjusts the supply pressure of the gaseous fuel; 2. The fuel supply device according to claim 1, wherein the temperature adjustment unit is provided between the pressure adjustment device and the gaseous fuel adjustment unit in the supply direction of the gaseous fuel.

[0098] <Appendix 4> a gaseous fuel storage section that stores the gaseous fuel; a gas fuel supply passage that connects the gas fuel storage section and the gas fuel adjusting section and allows the gas fuel to flow, 4. The fuel supply device according to claim 3, wherein the pressure regulator and the temperature regulator are provided in the gas fuel supply passage.

[0099] <Appendix 5> 5. The fuel supply device according to any one of claims 1 to 4, further comprising a chamber provided between the temperature adjusting unit and the gaseous fuel adjusting unit, for storing the gaseous fuel whose temperature has been adjusted.

[0100] <Appendix 6> the supply target is an engine having a plurality of cylinders, the gas fuel adjusting unit is a gas fuel supply valve provided in each of the plurality of cylinders, the gaseous fuel supply passage includes a common passage through which the gaseous fuel flows in common to the plurality of cylinders, 6. The fuel supply device according to claim 4, wherein the temperature adjusting unit is provided in the common passage.

[0101] <Appendix 7> a fuel supply device according to claim 6; An engine system comprising the engine, the temperature adjusting unit includes a heat exchange unit that circulates a heat exchange medium to act on the gaseous fuel, and a flow rate adjusting unit that adjusts a flow rate of the heat exchange medium, a control device that controls the gas fuel adjusting unit and the flow rate adjusting unit; the control device calculates a target temperature of the gaseous fuel based on a target output of the engine; an engine system, characterized in that, when a detected temperature of the gaseous fuel is lower than the target temperature, the flow rate adjusting unit is controlled to raise the temperature of the gaseous fuel so that the detected temperature becomes the target temperature.

[0102] <Appendix 8> a fuel supply device according to claim 6; An engine system comprising the engine, the temperature adjusting unit includes a heat exchange unit that circulates a heat exchange medium to act on the gaseous fuel, and a flow rate adjusting unit that adjusts a flow rate of the heat exchange medium, a control device that controls the gas fuel adjusting unit and the flow rate adjusting unit; The engine system is characterized in that the control device controls the flow rate adjustment unit to stop the flow of the heat exchange medium when a target output of the engine is equal to or greater than a predetermined output threshold.

[0103] <Appendix 9> a fuel supply device according to claim 6; An engine system comprising the engine, the temperature adjustment unit includes a heat exchange unit that circulates a heat exchange medium to act on the gaseous fuel, and a cooling device that cools the heat exchange medium, a control device that controls the gas fuel adjusting unit and the cooling device; The control device controls the cooling device to operate when a target output of the engine is equal to or greater than a predetermined output threshold. [Explanation of symbols]

[0104] 1 Engine System 2 Engines (supplied) 3 Fuel supply device 4. Generator 5 Liquid fuel supply section 10. Liquefied gas fuel tank (gas fuel storage section) 11 Gaseous fuel supply passage 11a Common passage 11b Branch passage 12. Vaporizer 13 Pressure Regulating Device 14 Temperature adjustment section 15 chambers 16 Gaseous fuel supply unit (gaseous fuel adjustment unit) 17 Control device 21 cylinders 25 Combustion chamber 36 First shutoff valve 37 Second shutoff valve 38 Open passage 39 Release valve 40 1st heat exchanger 41 1st flow rate adjustment section 42 Second heat exchanger 43 2nd flow adjustment unit 44 Cooling device

Claims

1. A fuel supply device that supplies at least gaseous fuel to a predetermined supply target, a gaseous fuel adjusting unit that adjusts the supply amount of the gaseous fuel to the supply target and supplies the adjusted amount; a temperature adjusting unit that adjusts the temperature of the gaseous fuel to be supplied to the gaseous fuel adjusting unit in accordance with an operating state and / or an operating environment of the target.

2. A fuel supply device that supplies at least gaseous fuel to a predetermined supply target, a gaseous fuel adjusting unit that adjusts the supply amount of the gaseous fuel to the supply target and supplies the adjusted amount; a supply pressure adjusting unit that adjusts the supply pressure of the gaseous fuel supplied to the gaseous fuel adjusting unit in accordance with an operating state and / or operating environment of the supply target.

3. a pressure regulating device that adjusts the supply pressure of the gaseous fuel; 2. The fuel supply device according to claim 1, wherein the temperature adjusting unit is provided between the pressure adjusting device and the gaseous fuel adjusting unit in the supply direction of the gaseous fuel.

4. a gaseous fuel storage section that stores the gaseous fuel; a gas fuel supply passage that connects the gas fuel storage section and the gas fuel adjusting section and allows the gas fuel to flow, 4. The fuel supply system according to claim 3, wherein the pressure regulator and the temperature regulator are provided in the gas fuel supply passage.

5. 2. The fuel supply device according to claim 1, further comprising a chamber provided between the temperature adjusting unit and the gaseous fuel adjusting unit, for storing the gaseous fuel whose temperature has been adjusted.

6. the supply target is an engine having a plurality of cylinders, the gas fuel adjusting unit is a gas fuel supply valve provided in each of the plurality of cylinders, the gaseous fuel supply passage includes a common passage through which the gaseous fuel flows in common to the plurality of cylinders, 5. The fuel supply device according to claim 4, wherein the temperature adjusting unit is provided in the common passage.

7. The fuel supply device according to claim 6; An engine system comprising the engine, the temperature adjusting unit includes a heat exchange unit that circulates a heat exchange medium to act on the gaseous fuel, and a flow rate adjusting unit that adjusts a flow rate of the heat exchange medium, a control device that controls the gas fuel adjusting unit and the flow rate adjusting unit; the control device calculates a target temperature of the gaseous fuel based on a target output of the engine; an engine system, characterized in that, when a detected temperature of the gaseous fuel is lower than the target temperature, the flow rate adjusting unit is controlled to raise the temperature of the gaseous fuel so that the detected temperature becomes the target temperature.

8. The fuel supply device according to claim 6; An engine system comprising the engine, the temperature adjusting unit includes a heat exchange unit that circulates a heat exchange medium to act on the gaseous fuel, and a flow rate adjusting unit that adjusts a flow rate of the heat exchange medium, a control device that controls the gas fuel adjusting unit and the flow rate adjusting unit; The engine system is characterized in that the control device controls the flow rate adjustment unit to stop the flow of the heat exchange medium when a target output of the engine is equal to or greater than a predetermined output threshold.

9. The fuel supply device according to claim 6; An engine system comprising the engine, the temperature adjustment unit includes a heat exchange unit that circulates a heat exchange medium to act on the gaseous fuel, and a cooling device that cools the heat exchange medium, a control device that controls the gas fuel adjusting unit and the cooling device; The control device controls the cooling device to operate when a target output of the engine is equal to or greater than a predetermined output threshold.

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