US20150275824A1 - Gas-fired engine - Google Patents
Gas-fired engine Download PDFInfo
- Publication number
- US20150275824A1 US20150275824A1 US14/735,633 US201514735633A US2015275824A1 US 20150275824 A1 US20150275824 A1 US 20150275824A1 US 201514735633 A US201514735633 A US 201514735633A US 2015275824 A1 US2015275824 A1 US 2015275824A1
- Authority
- US
- United States
- Prior art keywords
- gas
- pressure
- hydraulic
- pump
- hydraulic motor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
- F02M21/00—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form
- F02M21/02—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form for gaseous fuels
- F02M21/0203—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form for gaseous fuels characterised by the type of gaseous fuel
- F02M21/0215—Mixtures of gaseous fuels; Natural gas; Biogas; Mine gas; Landfill gas
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B37/00—Engines characterised by provision of pumps driven at least for part of the time by exhaust
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B43/00—Engines characterised by operating on gaseous fuels; Plants including such engines
- F02B43/10—Engines or plants characterised by use of other specific gases, e.g. acetylene, oxyhydrogen
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B43/00—Engines characterised by operating on gaseous fuels; Plants including such engines
- F02B43/10—Engines or plants characterised by use of other specific gases, e.g. acetylene, oxyhydrogen
- F02B43/12—Methods of operating
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D19/00—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
- F02D19/02—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures peculiar to engines working with gaseous fuels
- F02D19/021—Control of components of the fuel supply system
- F02D19/022—Control of components of the fuel supply system to adjust the fuel pressure, temperature or composition
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
- F02M21/00—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form
- F02M21/02—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form for gaseous fuels
- F02M21/0218—Details on the gaseous fuel supply system, e.g. tanks, valves, pipes, pumps, rails, injectors or mixers
- F02M21/0245—High pressure fuel supply systems; Rails; Pumps; Arrangement of valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
- F02M21/00—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form
- F02M21/02—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form for gaseous fuels
- F02M21/04—Gas-air mixing apparatus
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
- F02M21/00—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form
- F02M21/02—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form for gaseous fuels
- F02M21/06—Apparatus for de-liquefying, e.g. by heating
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B43/00—Engines characterised by operating on gaseous fuels; Plants including such engines
- F02B43/10—Engines or plants characterised by use of other specific gases, e.g. acetylene, oxyhydrogen
- F02B2043/103—Natural gas, e.g. methane or LNG used as a fuel
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B3/00—Engines characterised by air compression and subsequent fuel addition
- F02B3/06—Engines characterised by air compression and subsequent fuel addition with compression ignition
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B43/00—Engines characterised by operating on gaseous fuels; Plants including such engines
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/30—Use of alternative fuels, e.g. biofuels
Definitions
- PTL 1 described below discloses a configuration in which BOG in a gas tank is compressed in two stages by low-pressure and high-pressure compressors and introduced into an engine chamber as a propulsion engine for LNG-operated vessels.
- a geared or pulley speed reduction mechanism has been known as a typical speed reduction mechanism used for operating the reciprocating pump.
- the geared speed reduction mechanism is a speed reduction mechanism which combines a plurality of gears with different teeth numbers.
- the pulley speed reduction mechanism has a structure in which large and small wheels coupled via a V belt are rotated.
- the pressure of liquefied gas removed from a storage tank is boosted to a high pressure by a pump in a liquid state as disclosed in, for example, PTL 2 described below.
- the first problem relates to the speed reduction mechanism required in driving the electric motor for the reciprocating pump.
- the second problem relates to the electric motor that drives the reciprocating pump.
- a frequency control mechanism (an inverter) is required in both the cases in which the geared speed reduction mechanism is employed and the pulley speed reduction mechanism is employed.
- the frequency control mechanism of the electric motor has poor accuracy at low frequency, and thus, is not preferably used in a wide control range in which high accuracy control is required even in a very low-speed rotation region.
- the present invention has been made to solve the aforementioned problems, and it is an object thereof to provide a gas-fired engine which can supply liquefied gas (e.g., LNG) as fuel by boosting the pressure of liquefied gas to a high pressure by a reciprocating pump that can be easily arranged in a gas hazardous area in a high-pressure injection technique applied to a high-pressure gas injection diesel engine, such as an electronically-controlled slow-speed two-stroke diesel engine with high-pressure gas injection, which supplies high-pressure fuel gas (e.g., natural gas) into a combustion chamber.
- liquefied gas e.g., LNG
- a reciprocating pump that can be easily arranged in a gas hazardous area in a high-pressure injection technique applied to a high-pressure gas injection diesel engine, such as an electronically-controlled slow-speed two-stroke diesel engine with high-pressure gas injection, which supplies high-pressure fuel gas (e.g., natural gas) into a combustion chamber.
- high-pressure gas injection diesel engine such as an electronically-
- a gas-fired engine is a gas-fired engine for a high-pressure gas injection diesel engine including an electronic control unit that drives an engine by controlling high-pressure hydraulic oil by a controller and an electromagnetic valve, and a gas fuel supply device that boosts a pressure of liquefied gas as fuel gas to a high pressure and supplies the fuel gas into a combustion chamber by injection, wherein the gas fuel supply device includes: a reciprocating pump that is driven by a hydraulic motor to boost a pressure of liquefied gas introduced thereto to a desired pressure and discharge the liquefied gas; a hydraulic oil introduction line that introduces a portion of the high-pressure hydraulic oil from a hydraulic oil line of the electronic control unit, supplies the high-pressure hydraulic oil to the hydraulic motor, and thereby drives the hydraulic motor; a hydraulic oil return line that returns the high-pressure hydraulic oil used for driving the hydraulic motor to the hydraulic oil line; a heating unit that heats and gasifies the boosted liquefied gas supplied from the reciprocating pump; a control section
- the gas fuel supply device includes: the reciprocating pump that is driven by the hydraulic motor to boost the pressure of liquefied gas introduced thereto to a desired pressure and discharge the liquefied gas; the hydraulic oil introduction line that introduces a portion of the high-pressure hydraulic oil from the hydraulic oil line of the electronic control unit, supplies the high-pressure hydraulic oil to the hydraulic motor, and thereby drives the hydraulic motor; the hydraulic oil return line that returns the high-pressure hydraulic oil used for driving the hydraulic motor to the hydraulic oil line; the heating unit that heats and gasifies the boosted liquefied gas supplied from the reciprocating pump; the control section that adjusts the rotational speed of the hydraulic motor to maintain constant the gas fuel outlet pressure of the heating unit; and the engine inlet gas pressure reducing valve that regulates the pressure of gas fuel to be injected into the combustion chamber. Accordingly, the pressure of the liquefied gas can be boosted by the reciprocating pump driven by the hydraulic motor with a minimum number of additional devices by effectively using the high-pressure hydraulic oil of the
- an engine-driving hydraulic pump that supplies the high-pressure hydraulic oil to the electronic control unit also has a higher discharge rate and a higher hydraulic pressure.
- the high-pressure hydraulic oil of the electronic control unit is a favorable hydraulic power source.
- the reciprocating pump driven by the hydraulic motor, and a hydraulic pump unit that supplies a hydraulic pressure to the hydraulic motor can be connected together via a hydraulic pipe, and can be thereby mounted separately from each other.
- the reciprocating pump having no electric device and no speed reduction mechanism can be easily installed in a gas hazardous area.
- a gas-fired engine is a gas-fired engine for a high-pressure gas injection diesel engine including a gas fuel supply device that boosts a pressure of liquefied gas as fuel gas to a high pressure and supplies the fuel gas into a combustion chamber by injection, wherein the gas fuel supply device includes: a reciprocating pump that is driven by a hydraulic motor to boost a pressure of liquefied gas introduced thereto to a desired pressure and discharge the liquefied gas; a hydraulic pump unit that supplies a driving hydraulic pressure to the hydraulic motor from a hydraulic pump driven by a rotating shaft of an exhaust turbine, the exhaust turbine being operated by extracting a portion of exhaust gas from an engine exhaust static-pressure pipe; a heating unit that heats and gasifies the boosted liquefied gas supplied from the reciprocating pump; a control section that adjusts a rotational speed of the hydraulic motor to maintain constant a gas fuel outlet pressure of the heating unit; and an engine inlet gas pressure reducing valve that regulates a pressure of gas fuel to be
- the gas fuel supply device includes: the reciprocating pump that is driven by the hydraulic motor to boost the pressure of liquefied gas introduced thereto to a desired pressure and discharge the liquefied gas; the hydraulic pump unit that supplies the driving hydraulic pressure to the hydraulic motor from the hydraulic pump driven by the exhaust turbine, the exhaust turbine being operated by extracting a portion of exhaust gas from the engine exhaust static-pressure pipe; the heating unit that heats and gasifies the boosted liquefied gas supplied from the reciprocating pump; the control section that adjusts the rotational speed of the hydraulic motor to maintain constant the gas fuel outlet pressure of the heating unit; and the engine inlet gas pressure reducing valve that regulates the pressure of gas fuel to be injected into the combustion chamber.
- the hydraulic pump unit is driven by effectively using the exhaust gas which is generated in a larger amount with an increase in engine load.
- the pressure of the liquefied gas can be boosted by the reciprocating pump driven by the hydraulic motor.
- the amount of exhaust gas increases with the increase in engine load.
- the hydraulic pump driven by the exhaust turbine is a favorable hydraulic power source.
- the pressure of the liquefied gas can be also boosted by the reciprocating pump driven by the hydraulic motor with a minimum number of additional devices.
- the hydraulic pump unit is driven by effectively using the exhaust gas which is generated in a larger amount with an increase in engine load.
- the pressure of the liquefied gas can be boosted by the reciprocating pump driven by the hydraulic motor.
- the amount of exhaust gas increases with the increase in engine load.
- the hydraulic pump driven by the exhaust turbine is a favorable hydraulic power source.
- the pressure of the liquefied gas can be also boosted by the reciprocating pump driven by the hydraulic motor with a minimum number of additional devices.
- the reciprocating pump driven by the hydraulic motor, and the hydraulic pump unit that supplies the hydraulic pressure to the hydraulic motor can be connected together via a hydraulic pipe, and can be thereby mounted separately from each other.
- the reciprocating pump having no electric device and no speed reduction mechanism can be easily installed in a gas hazardous area.
- the rotational speed of the hydraulic motor that drives the reciprocating pump is adjusted by controlling the number of rotations of the exhaust turbine on the drive side. It is thus not necessary to provide a speed reduction mechanism or control the number of rotations of an electric motor.
- the reciprocating pump driven by the hydraulic motor, and the hydraulic pump unit that supplies the hydraulic pressure to the hydraulic motor can be connected together via a hydraulic pipe, and can be thereby mounted separately from each other.
- the reciprocating pump having no electric device and no speed reduction mechanism can be easily installed in a gas hazardous area.
- the above gas-fired engine according to the present invention can supply liquefied gas (e.g., LNG) as fuel by boosting the pressure of liquefied gas to a high pressure by the reciprocating pump that is driven by the hydraulic motor and can be easily arranged in a gas hazardous area in the high-pressure gas injection diesel engine, such as an electronically-controlled slow-speed two-stroke diesel engine with high-pressure gas injection, which supplies high-pressure fuel gas (e.g., natural gas) into the combustion chamber.
- liquefied gas e.g., LNG
- the reciprocating pump that is driven by the hydraulic motor
- high-pressure gas injection diesel engine such as an electronically-controlled slow-speed two-stroke diesel engine with high-pressure gas injection, which supplies high-pressure fuel gas (e.g., natural gas) into the combustion chamber.
- high-pressure fuel gas e.g., natural gas
- a gas-fired engine 1 according to the embodiment shown in FIG. 1 is a high-pressure gas injection diesel engine including an electronic control unit 60 that drives an engine by controlling high-pressure hydraulic oil by a controller and an electromagnetic valve, and a gas fuel supply device 10 that boosts the pressure of liquefied gas as fuel gas to a high pressure and supplies the fuel gas into a combustion chamber of the engine by injection.
- a pressure sensor (not shown) is provided adjacent to an outlet of the heating unit 30 .
- a natural gas outlet pressure PV detected by the pressure sensor is input to the control section as a gas fuel outlet pressure.
- the control section adjusts the rotational speed of the hydraulic motor 50 described below so as to maintain the natural gas outlet pressure PV at a predefined constant pressure value.
- the control section may be provided integrally with a control section of the electronic control unit 60 described below.
- the suction drum 24 is an LNG container that collects the LNG branched and introduced from the LNG supply pipe 22 , and returns the LNG to a recirculation suction section of the reciprocating pump 20 .
- the recirculation flow rate of the LNG introduced into the recirculation line 23 is regulated by the recirculation control valve 25 that operates based on a control signal for the operational point OP output from the control section.
- the control signal for the operational point OP is an opening signal that defines the operational point output from the control section based on a setting point SP obtained from the number of rotations of the engine, and the natural gas outlet pressure PV detected by the pressure sensor.
- the setting point SP in this case may employ a variable value, such as a highly-controllable pressure value of the gas pressure reducing valve 40 , in addition to the number of rotations of the engine, or may be a fixed value.
- the hydraulic system in this case introduces a portion of hydraulic pressure held by the electronic control unit 60 , and supplies the hydraulic pressure to the hydraulic motor 50 that drives the reciprocating pump 20 .
- the hydraulic system includes a hydraulic oil introduction line 51 that introduces a portion of high-pressure hydraulic oil from a hydraulic oil line 61 of the electronic control unit 60 , supplies the high-pressure hydraulic oil to the hydraulic motor 50 , and thereby drives the hydraulic motor 50 , and a hydraulic oil return line 52 that returns the high-pressure hydraulic oil used for driving the hydraulic motor 50 to the hydraulic oil line 61 .
- the hydraulic oil line 61 of the electronic control unit 60 uses a portion of engine lubricant oil stored in a crankcase 62 as the high-pressure hydraulic oil.
- the engine lubricant oil in the crankcase 62 is supplied to a filter unit 65 by an electric lubricant oil pump 64 provided in a lubricant oil line 63 .
- the pressure of the engine lubricant oil is boosted by an engine drive pump 66 or an electric pump 67 to obtain the high-pressure hydraulic oil.
- the high-pressure hydraulic oil is thereby supplied to the hydraulic oil line 61 .
- the electric pump 67 described above is required at the time of engine start up.
- the engine drive pump 66 is mainly used to supply the hydraulic pressure at the time of normal operation after the engine start up.
- the hydraulic oil introduction line 51 is a pipe line that branches from the hydraulic oil line 61 upstream of the electronic control unit 60 , and supplies a portion of the high-pressure hydraulic oil to the hydraulic motor 50 .
- the hydraulic oil return line 52 is a pipe line that returns the high-pressure hydraulic oil used for driving the hydraulic motor 50 to the hydraulic oil line 61 .
- a sub-storage tank 53 that temporarily stores the high-pressure hydraulic oil used for driving the hydraulic motor 50 is provided in the hydraulic oil return line 52 .
- the hydraulic fluid stored in the sub-storage tank 53 is returned to the crankcase 62 through the hydraulic oil return line 52 by operating an electric oil return pump 54 .
- Reference numeral 55 in the drawing denotes a pipe line that connects the hydraulic oil introduction line 51 and the sub-storage tank 53
- reference numeral 56 denotes a check valve provided in the pipe line 55 . Since the pipe line 55 and the check valve 56 are provided, the hydraulic oil introduction line 51 can be prevented from coming under negative pressure by sucking the hydraulic fluid from the sub-storage tank 53 in case of an emergency stop of the engine or the like.
- the gas-fired engine 1 as described above can change the number of rotations of the engine to any number based on a vessel speed within a vessel. For example, the number of rotations of the engine increases with an increase in engine load.
- the engine drive pump 66 that supplies the high-pressure hydraulic oil to the electronic control unit 60 also has a higher discharge rate and a higher hydraulic pressure.
- the high-pressure hydraulic oil of the electronic control unit 60 is a favorable hydraulic power source.
- the LNG discharge rate of the reciprocating pump 20 can be controlled by the number of rotations and the hydraulic pressure of the hydraulic motor 50 . Accordingly, the LNG supply to the heating unit 30 can be easily controlled (increased or decreased) in conjunction with an increase or a decrease in the supply and the hydraulic pressure of the high-pressure hydraulic oil in association with variation in engine load.
- the hydraulic pressure is supplied from the main engine of a vessel, it is not necessary to drive a power-generating four-stroke engine having lower thermal efficiency than the main two-stroke engine so as to supply driving electricity to the separately-mounted hydraulic unit. Thus, the operating cost can be reduced.
- FIG. 2 a gas-fired engine according to a second embodiment of the present invention will be described based on FIG. 2 .
- the same portions as those of the aforementioned embodiment are assigned the same reference numerals, and the detailed description is omitted.
- a gas-fired engine 1 A according to the embodiment shown in FIG. 2 includes a gas fuel supply device 10 A having a different configuration from that of the aforementioned embodiment.
- the gas fuel supply device 10 A while the LNG fuel system has substantially the same configuration as that of the aforementioned embodiment, the hydraulic system that supplies the hydraulic pressure to the hydraulic motor 50 has a different configuration.
- the hydraulic system in this case drives a hydraulic pump 70 of the hydraulic pump unit that supplies the driving hydraulic pressure to the hydraulic motor 50 by effectively using exhaust gas of the gas-fired engine 1 A.
- the hydraulic pump 70 is a variable capacity pump that uses as a drive source an exhaust turbine 81 operated by extracting a portion of exhaust gas from an engine exhaust static-pressure pipe 80 .
- the hydraulic pump 70 is a plunger pump.
- An exhaust gas supply flow passage 82 that introduces a portion of the exhaust gas from the engine exhaust static-pressure pipe 80 , and an exhaust gas discharge flow passage 83 that guides the exhaust gas working in the exhaust turbine 81 to a funnel for release to the atmosphere are connected to the exhaust turbine 81 .
- An exhaust gas flow control valve 84 is provided in the exhaust gas supply flow passage 82 so as to regulate the flow rate of the exhaust gas supplied to the exhaust turbine 81 when needed.
- An exhaust gas bypass flow passage 85 that branches from the exhaust gas supply flow passage 82 upstream of the exhaust gas flow control valve 84 is also provided in the exhaust gas supply flow passage 82 .
- the exhaust gas bypass flow passage 85 is connected to the exhaust gas discharge flow passage 83 .
- a bypass flow regulating valve 86 and an orifice 87 are provided in the exhaust gas bypass flow passage.
- the main stream of the exhaust gas discharged from the engine exhaust static-pressure pipe 80 passes through a main exhaust gas supply flow passage 88 to be supplied to an exhaust turbine 89 a of a turbocharger 89 .
- the exhaust gas main stream is guided to the funnel through a main exhaust gas discharge flow passage 90 after driving the exhaust turbine 89 a.
- the above exhaust gas discharge flow passage 83 is connected to the main exhaust gas discharge flow passage 90 .
- a compressor 89 b driven by a rotating shaft of the exhaust turbine 89 a suctions and compresses air within an engine chamber.
- the compressed air for aeration (scavenging) compressed by the compressor 89 b is cooled in an air cooler 91 to increase the air density.
- the air is thereby supplied to an intake manifold 92 .
- Reference numeral 93 in the drawing denotes a cylinder of the gas-fired engine 1 A.
- the gas-fired engine 1 A has six cylinders in the configuration example in the drawing, the present invention is not limited thereto.
- the high-pressure hydraulic oil discharged from the hydraulic pump 70 is supplied to the hydraulic motor 50 through a hydraulic oil introduction line 51 A.
- the hydraulic fluid flowing into the sub-storage tank 53 after driving the hydraulic motor 50 is returned to a hydraulic fluid storage tank 59 by use of the electric oil return pump 54 .
- the gas fuel supply device 10 A includes the hydraulic pump 70 of the hydraulic pump unit that supplies the driving hydraulic pressure to the hydraulic motor 50 from the hydraulic pump 70 driven by the exhaust turbine 81 , the exhaust turbine 81 being operated by extracting a portion of the exhaust gas from the engine exhaust static-pressure pipe 80 . Accordingly, the hydraulic pump 70 is driven by effectively using the exhaust gas which is generated in a larger amount with an increase in engine load.
- the pressure of the LNG can be boosted by the reciprocating pump 20 driven by the hydraulic motor.
- the hydraulic pump 70 driven by the exhaust turbine 81 is a favorable hydraulic power supply source since variation in required fuel and variation in hydraulic pressure to be supplied to the hydraulic motor 50 that drives the reciprocating pump 20 on the fuel supply side show substantially the same tendency.
- the hydraulic system according to the above embodiment can boost the pressure of the liquefied gas by the reciprocating pump 20 driven by the hydraulic motor 50 with a minimum number of additional devices.
- the rotational speed of the hydraulic motor 50 that drives the reciprocating pump 20 can be also adjusted by controlling the number of rotations of the exhaust turbine on the drive side. It is thus not necessary to provide a speed reduction mechanism or control the rotation number of an electric motor.
- FIG. 3 a gas-fired engine according to a third embodiment of the present invention will be described based on FIG. 3 .
- the same portions as those of the aforementioned embodiment are assigned the same reference numerals, and the detailed description is omitted.
- the high-pressure hydraulic oil discharged from the hydraulic pump 70 A is supplied to the hydraulic motor 50 through the hydraulic oil introduction line 51 A.
- the hydraulic fluid flowing into the sub-storage tank 53 after driving the hydraulic motor 50 is returned to the hydraulic fluid storage tank 59 by use of the electric oil return pump 54 .
- the hydraulic system according to the above embodiment can boost the pressure of the liquefied gas by the reciprocating pump 20 driven by the hydraulic motor 50 with a minimum number of additional devices.
- variable capacity control As described above, the rotational speed of the hydraulic motor 50 that drives the reciprocating pump 20 is adjusted by performing capacity control (oil control) of the hydraulic pump 70 A. It is thus not necessary to provide a speed reduction mechanism or control the rotation number of an electric motor.
- the reciprocating pump 20 driven by the hydraulic motor 50 , and the hydraulic pump unit (the hydraulic pump 70 A) that supplies the hydraulic pressure to the hydraulic motor 50 can be connected together via the hydraulic pipe, and can be thereby mounted separately from each other.
- the reciprocating pump 20 having no electric device and no speed reduction mechanism can be easily installed in a gas hazardous area.
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Output Control And Ontrol Of Special Type Engine (AREA)
- Fuel-Injection Apparatus (AREA)
Abstract
A gas-fired engine which supplies high-pressure liquefied gas (e.g., LNG) as fuel by a reciprocating pump. A gas fuel supply device includes: a reciprocating pump driven by a hydraulic motor to boost an introduced liquefied gas pressure to a desired pressure and discharge the liquefied gas; a hydraulic oil introduction line that introduces a portion of high-pressure hydraulic oil from a hydraulic oil line and supplies the high-pressure hydraulic oil to the hydraulic motor; a hydraulic oil return line that returns the high-pressure hydraulic oil to the hydraulic oil line; a heating unit that heats and gasifies the boosted liquefied gas; a control section that adjusts a rotational speed of the hydraulic motor to maintain constant a gas fuel outlet pressure of the heating unit; and an engine inlet gas pressure-reducing valve that regulates a gas fuel pressure injected into a combustion chamber.
Description
- This is a divisional of application Ser. No. 13/985,065, which is the National Stage of International Application No. PCT/JP2012/056695, filed Mar. 15, 2012.
- The present invention relates to a gas-fired engine which is applied to, for example, main engines or generator drive engines of vessels, and operated with gas fuel such as natural gas as fuel.
- There are various conventional diesel engines which are operated with natural gas obtained by gasifying liquefied natural gas (referred to as “LNG” below) as fuel. In recent years, slow-speed two-stroke diesel engines with high-pressure gas injection (referred to as “SSD-GI” below) are attracting attention as a measure to improve the environmental emission efficiency of existing oil-fired slow-speed diesel main engines. The SSD-GI is an engine having higher thermal efficiency and higher response than a conventional heat engine using LNG (e.g., a steam turbine), and capable of outputting power at low speed. The SSD-GI can be driven in direct connection with a propeller.
- However, unlike the proven oil-fired diesel engines, a high-pressure injection technique for supplying high-pressure natural gas (about 150 to 300 bar) into a combustion chamber has not been sufficiently developed for the SSD-GI which uses natural gas as fuel. There appears to be no established technique for supplying LNG fuel.
- When the SSD-GI was considered as a potential main engine for LNG vessels, a method for using boil off gas (referred to as “BOG” below) as engine fuel by compressing BOG having a substantially atmospheric pressure by a multi-stage gas compressor and cooling the BOG during or after the compressing process was studied. However, the method of compressing and cooling BOG has a disadvantage that a large facility is required and large power is consumed.
- For example,
PTL 1 described below (seeFIG. 7 or the like) discloses a configuration in which BOG in a gas tank is compressed in two stages by low-pressure and high-pressure compressors and introduced into an engine chamber as a propulsion engine for LNG-operated vessels. - Meanwhile, recently, a BOG re-liquefaction system has been achieved in LNG vessels. Thus, BOG does not need to be used as fuel, and can be liquefied and stored. In conventional LNG vessels, there has been an effort to develop a method for using BOG as fuel from the perspective of effective use of BOG. However, the problem in employing LNG as the main fuel of a main engine has been almost solved because of the BOG re-liquefaction system. In a case in which LNG is used as fuel in vessels other than the LNG vessels, no BOG treatment is required when a pressurized LNG tank is employed.
- Based on such background, LNG with excellent environmental emission efficiency is recently attracting attention as the fuel of a marine main engine or the like. Various researches and developments have been carried out to develop a method for using LNG or the like.
- As a method for supplying natural gas as fuel by high-pressure injection, LNG may be heated and gasified after the pressure is boosted to a high pressure. To boost the pressure of LNG, a reciprocating pump is typically used. The reciprocating pump, which has a rotational speed of about 300 rpm, is much slower than a general electric motor, which has a rotational speed of 1800 to 3600 rpm. Thus, when the reciprocating pump is driven by the electric motor, a speed reduction mechanism is required to reduce the rotational speed to that of the reciprocating pump.
- A geared or pulley speed reduction mechanism has been known as a typical speed reduction mechanism used for operating the reciprocating pump. The geared speed reduction mechanism is a speed reduction mechanism which combines a plurality of gears with different teeth numbers. The pulley speed reduction mechanism has a structure in which large and small wheels coupled via a V belt are rotated.
- In a plant for re-gasification of liquefied gas, the pressure of liquefied gas removed from a storage tank is boosted to a high pressure by a pump in a liquid state as disclosed in, for example, PTL 2 described below.
- In marine diesel engines, electronically-controlled engines with high environmental responsiveness which can reduce nitrogen oxides emissions or the like have been recently developed in response to a worldwide tightening of regulations on exhaust emissions from marine engines. In the electronically-controlled engines, the driving of at least one of a fuel injection system, an exhaust valve train system, a start-up system, and a cylinder lubrication system, which are driven by a camshaft in conventional engines, is electronically controlled. The electronically-controlled engines employ a method of controlling high-pressure hydraulic oil by a controller and an electromagnetic valve and thereby driving respective units of the engine.
- Japanese Unexamined Patent Application, Publication No. Hei9-209788
- Japanese Unexamined Patent Application, Publication No. 2009-204026
- As described above, while the LNG is recently attracting attention as the fuel of a marine main engine, there has been no established technique for supplying high-pressure gas so as to inject high-pressure natural gas into a combustion chamber. To inject high-pressure natural gas as engine fuel, it is considered necessary to boost the pressure of LNG by the reciprocating pump. Following problems in controlling the driving of the reciprocating pump have been pointed out. To be more specific, when the electric motor is used as a drive source of the reciprocating pump by employing an operating method of reducing the rotational speed of the electric motor to that of the reciprocating pump via the speed reduction mechanism, the following problems occur in the speed reduction mechanism and the electric motor.
- The first problem relates to the speed reduction mechanism required in driving the electric motor for the reciprocating pump.
- To be more specific, the geared speed reduction mechanism is expected to suffer damage at tooth surfaces or roots of the gears due to torque variation from the reciprocating pump side. In consideration of durability against long-term continuous operation, it is necessary to provide a coupling such as an elastic coupling and an inertia wheel so as to absorb the torque variation.
- Meanwhile, the pulley speed reduction mechanism has an advantage that torque variation specific to a piston pump can be absorbed by belt slip. However, since the belt is an expendable item and needs to be replaced within a short period of time, the pulley speed reduction mechanism is not suitable for long-term continuous use. Since sparks may be generated in an exposed high-speed contact portion, the pulley speed reduction mechanism is not preferably installed in a gas hazardous area for safety reasons.
- The second problem relates to the electric motor that drives the reciprocating pump.
- To be more specific, when the rotational speed of the electric motor is reduced to the rotational speed of the reciprocating pump by the speed reduction mechanism, a frequency control mechanism (an inverter) is required in both the cases in which the geared speed reduction mechanism is employed and the pulley speed reduction mechanism is employed. However, the frequency control mechanism of the electric motor has poor accuracy at low frequency, and thus, is not preferably used in a wide control range in which high accuracy control is required even in a very low-speed rotation region.
- In a case in which electric devices such as the electric motor are installed in a gas hazardous area, there are restrictions on usable devices. Thus, there are also restrictions on installation of the reciprocating pump driven by the electric motor in a gas hazardous area.
- The present invention has been made to solve the aforementioned problems, and it is an object thereof to provide a gas-fired engine which can supply liquefied gas (e.g., LNG) as fuel by boosting the pressure of liquefied gas to a high pressure by a reciprocating pump that can be easily arranged in a gas hazardous area in a high-pressure injection technique applied to a high-pressure gas injection diesel engine, such as an electronically-controlled slow-speed two-stroke diesel engine with high-pressure gas injection, which supplies high-pressure fuel gas (e.g., natural gas) into a combustion chamber.
- To achieve the above object, the present invention employs the following solutions.
- A gas-fired engine according to a first aspect of the present invention is a gas-fired engine for a high-pressure gas injection diesel engine including an electronic control unit that drives an engine by controlling high-pressure hydraulic oil by a controller and an electromagnetic valve, and a gas fuel supply device that boosts a pressure of liquefied gas as fuel gas to a high pressure and supplies the fuel gas into a combustion chamber by injection, wherein the gas fuel supply device includes: a reciprocating pump that is driven by a hydraulic motor to boost a pressure of liquefied gas introduced thereto to a desired pressure and discharge the liquefied gas; a hydraulic oil introduction line that introduces a portion of the high-pressure hydraulic oil from a hydraulic oil line of the electronic control unit, supplies the high-pressure hydraulic oil to the hydraulic motor, and thereby drives the hydraulic motor; a hydraulic oil return line that returns the high-pressure hydraulic oil used for driving the hydraulic motor to the hydraulic oil line; a heating unit that heats and gasifies the boosted liquefied gas supplied from the reciprocating pump; a control section that adjusts a rotational speed of the hydraulic motor to maintain constant a gas fuel outlet pressure of the heating unit; and an engine inlet gas pressure reducing valve that regulates a pressure of gas fuel to be injected into the combustion chamber.
- In the gas-fired engine according to the first aspect, the gas fuel supply device includes: the reciprocating pump that is driven by the hydraulic motor to boost the pressure of liquefied gas introduced thereto to a desired pressure and discharge the liquefied gas; the hydraulic oil introduction line that introduces a portion of the high-pressure hydraulic oil from the hydraulic oil line of the electronic control unit, supplies the high-pressure hydraulic oil to the hydraulic motor, and thereby drives the hydraulic motor; the hydraulic oil return line that returns the high-pressure hydraulic oil used for driving the hydraulic motor to the hydraulic oil line; the heating unit that heats and gasifies the boosted liquefied gas supplied from the reciprocating pump; the control section that adjusts the rotational speed of the hydraulic motor to maintain constant the gas fuel outlet pressure of the heating unit; and the engine inlet gas pressure reducing valve that regulates the pressure of gas fuel to be injected into the combustion chamber. Accordingly, the pressure of the liquefied gas can be boosted by the reciprocating pump driven by the hydraulic motor with a minimum number of additional devices by effectively using the high-pressure hydraulic oil of the electronic control unit.
- In the gas-fired engine as described above, the number of rotations of the engine increases with an increase in engine load. Thus, an engine-driving hydraulic pump that supplies the high-pressure hydraulic oil to the electronic control unit also has a higher discharge rate and a higher hydraulic pressure. For the reciprocating pump for boosting the pressure of liquefied gas in which a higher flow rate and a higher pressure are required when the consumption of fuel (gasified liquefied gas) increases, the high-pressure hydraulic oil of the electronic control unit is a favorable hydraulic power source.
- In the gas-fired engine according to the first aspect, the rotational speed of the hydraulic motor may be controlled by adjusting a discharge rate of a hydraulic pump that supplies the high-pressure hydraulic oil to the electronic control unit. That is, since the rotational speed of the hydraulic motor that drives the reciprocating pump is controlled by performing capacity control (oil control) of the hydraulic pump that supplies the high-pressure hydraulic oil to the electronic control unit, it is not necessary to additionally provide a speed reduction mechanism or additionally control the number of rotations of an electric motor.
- The reciprocating pump driven by the hydraulic motor, and a hydraulic pump unit that supplies a hydraulic pressure to the hydraulic motor can be connected together via a hydraulic pipe, and can be thereby mounted separately from each other. Thus, the reciprocating pump having no electric device and no speed reduction mechanism can be easily installed in a gas hazardous area.
- A gas-fired engine according to a second aspect of the present invention is a gas-fired engine for a high-pressure gas injection diesel engine including a gas fuel supply device that boosts a pressure of liquefied gas as fuel gas to a high pressure and supplies the fuel gas into a combustion chamber by injection, wherein the gas fuel supply device includes: a reciprocating pump that is driven by a hydraulic motor to boost a pressure of liquefied gas introduced thereto to a desired pressure and discharge the liquefied gas; a hydraulic pump unit that supplies a driving hydraulic pressure to the hydraulic motor from a hydraulic pump driven by a rotating shaft of an exhaust turbine, the exhaust turbine being operated by extracting a portion of exhaust gas from an engine exhaust static-pressure pipe; a heating unit that heats and gasifies the boosted liquefied gas supplied from the reciprocating pump; a control section that adjusts a rotational speed of the hydraulic motor to maintain constant a gas fuel outlet pressure of the heating unit; and an engine inlet gas pressure reducing valve that regulates a pressure of gas fuel to be injected into the combustion chamber.
- In the gas-fired engine according to the second aspect, the gas fuel supply device includes: the reciprocating pump that is driven by the hydraulic motor to boost the pressure of liquefied gas introduced thereto to a desired pressure and discharge the liquefied gas; the hydraulic pump unit that supplies the driving hydraulic pressure to the hydraulic motor from the hydraulic pump driven by the exhaust turbine, the exhaust turbine being operated by extracting a portion of exhaust gas from the engine exhaust static-pressure pipe; the heating unit that heats and gasifies the boosted liquefied gas supplied from the reciprocating pump; the control section that adjusts the rotational speed of the hydraulic motor to maintain constant the gas fuel outlet pressure of the heating unit; and the engine inlet gas pressure reducing valve that regulates the pressure of gas fuel to be injected into the combustion chamber. Accordingly, the hydraulic pump unit is driven by effectively using the exhaust gas which is generated in a larger amount with an increase in engine load. The pressure of the liquefied gas can be boosted by the reciprocating pump driven by the hydraulic motor. In this case, the amount of exhaust gas increases with the increase in engine load. For the reciprocating pump for boosting the pressure of liquefied gas in which a higher flow rate and a higher pressure are required when the consumption of fuel (gasified liquefied gas) increases, the hydraulic pump driven by the exhaust turbine is a favorable hydraulic power source.
- The pressure of the liquefied gas can be also boosted by the reciprocating pump driven by the hydraulic motor with a minimum number of additional devices.
- A gas-fired engine according to a third aspect of the present invention is a gas-fired engine for a high-pressure gas injection diesel engine including a turbocharger, and a gas fuel supply device that boosts a pressure of liquefied gas as fuel gas to a high pressure and supplies the fuel gas into a combustion chamber by injection, wherein the gas fuel supply device includes: a reciprocating pump that is driven by a hydraulic motor to boost a pressure of liquefied gas introduced thereto to a desired pressure and discharge the liquefied gas; a hydraulic pump unit that supplies a driving hydraulic pressure to the hydraulic motor from a hydraulic pump driven by a rotating shaft of the turbocharger; a heating unit that heats and gasifies the boosted liquefied gas supplied from the reciprocating pump; a control section that adjusts a rotational speed of the hydraulic motor to maintain constant a gas fuel outlet pressure of the heating unit; and an engine inlet gas pressure reducing valve that regulates a pressure of gas fuel to be injected into the combustion chamber.
- In the gas-fired engine according to the third aspect, the gas fuel supply device includes: the reciprocating pump that is driven by the hydraulic motor to boost the pressure of liquefied gas introduced thereto to a desired pressure and discharge the liquefied gas; the hydraulic pump unit that supplies the driving hydraulic pressure to the hydraulic motor from the hydraulic pump driven by the rotating shaft of the turbocharger; the heating unit that heats and gasifies the boosted liquefied gas supplied from the reciprocating pump; the control section that adjusts the rotational speed of the hydraulic motor to maintain constant the gas fuel outlet pressure of the heating unit; and the engine inlet gas pressure reducing valve that regulates the pressure of gas fuel to be injected into the combustion chamber. Accordingly, the hydraulic pump unit is driven by effectively using the exhaust gas which is generated in a larger amount with an increase in engine load. The pressure of the liquefied gas can be boosted by the reciprocating pump driven by the hydraulic motor. In this case, the amount of exhaust gas increases with the increase in engine load. For the reciprocating pump for boosting the pressure of liquefied gas in which a higher flow rate and a higher pressure are required when the consumption of fuel (gasified liquefied gas) increases, the hydraulic pump driven by the exhaust turbine is a favorable hydraulic power source.
- The pressure of the liquefied gas can be also boosted by the reciprocating pump driven by the hydraulic motor with a minimum number of additional devices.
- In the gas-fired engine according to the second or third aspect, in the gas fuel supply device, the hydraulic pump may be a variable capacity pump, and the control section may adjust the rotational speed of the hydraulic motor by variable capacity control of the hydraulic pump to maintain constant the gas fuel outlet pressure. Accordingly, the rotational speed of the hydraulic motor that drives the reciprocating pump is adjusted by performing capacity control (oil control) of the hydraulic pump. It is thus not necessary to provide a speed reduction mechanism or control the number of rotations of an electric motor. As preferable variable capacity control in this case, for example, a swash plate pump may be employed as the hydraulic pump, and the angle of the swash plate may be appropriately adjusted to control the pump discharge rate.
- The reciprocating pump driven by the hydraulic motor, and the hydraulic pump unit that supplies the hydraulic pressure to the hydraulic motor can be connected together via a hydraulic pipe, and can be thereby mounted separately from each other. Thus, the reciprocating pump having no electric device and no speed reduction mechanism can be easily installed in a gas hazardous area.
- In the gas-fired engine according to the second aspect, in the gas fuel supply device, the hydraulic pump may be a constant capacity pump, and the control section may adjust the rotational speed of the hydraulic motor by rotation number control of the exhaust turbine to maintain constant the gas fuel outlet pressure. In this case, an exhaust gas flow control valve may be provided on an inlet side of the exhaust turbine, and the opening degree of the valve may be appropriately adjusted to control the number of rotations of the exhaust turbine.
- Accordingly, the rotational speed of the hydraulic motor that drives the reciprocating pump is adjusted by controlling the number of rotations of the exhaust turbine on the drive side. It is thus not necessary to provide a speed reduction mechanism or control the number of rotations of an electric motor. The reciprocating pump driven by the hydraulic motor, and the hydraulic pump unit that supplies the hydraulic pressure to the hydraulic motor can be connected together via a hydraulic pipe, and can be thereby mounted separately from each other. Thus, the reciprocating pump having no electric device and no speed reduction mechanism can be easily installed in a gas hazardous area.
- The above gas-fired engine according to the present invention can supply liquefied gas (e.g., LNG) as fuel by boosting the pressure of liquefied gas to a high pressure by the reciprocating pump that is driven by the hydraulic motor and can be easily arranged in a gas hazardous area in the high-pressure gas injection diesel engine, such as an electronically-controlled slow-speed two-stroke diesel engine with high-pressure gas injection, which supplies high-pressure fuel gas (e.g., natural gas) into the combustion chamber.
- Since the hydraulic pressure is supplied from the electronic control unit on the engine side, it is not necessary to install a new hydraulic unit for supplying the hydraulic pressure to the hydraulic motor that drives the reciprocating pump. Consequently, the installation space and the cost of the gas-fired engine can be reduced. Especially in a vessel with limited space, the space within the vessel can be effectively used by increasing a cargo space or the like.
- In the method for driving the hydraulic pump by use of the shaft output of the exhaust turbine or the turbocharger operated with exhaust gas, the number of devices constituting the hydraulic unit that supplies the hydraulic pressure to the hydraulic motor for driving the reciprocating pump can be minimized. Consequently, the installation space and the cost of the gas-fired engine can be reduced. Especially in a vessel with limited space, the space within the vessel can be effectively used by increasing a cargo space or the like.
-
FIG. 1 is a system diagram illustrating a first embodiment of a gas-fired engine as one embodiment of the present invention. -
FIG. 2 is a system diagram illustrating a second embodiment of the gas-fired engine as one embodiment of the present invention. -
FIG. 3 is a system diagram illustrating a third embodiment of the gas-fired engine as one embodiment of the present invention. -
FIG. 4 is an explanatory view showing the pump load of a reciprocating pump and the opening degree of a recirculation control valve (RCV) on a vertical axis with an operational point (OP) on a horizontal axis. - In the following, one embodiment of a gas-fired engine according to the present invention will be described based on the drawing.
- A gas-fired
engine 1 according to the embodiment shown inFIG. 1 is a high-pressure gas injection diesel engine including anelectronic control unit 60 that drives an engine by controlling high-pressure hydraulic oil by a controller and an electromagnetic valve, and a gasfuel supply device 10 that boosts the pressure of liquefied gas as fuel gas to a high pressure and supplies the fuel gas into a combustion chamber of the engine by injection. - The
electronic control unit 60 described below electronically controls the driving of at least one of a fuel injection system, an exhaust valve train system, a start-up system, and a cylinder lubrication system of the gas-firedengine 1, which are driven by a camshaft in conventional engines. - The gas
fuel supply device 10 with “high-pressure mode” is provided in the gas-firedengine 1 in the drawing. In the “high-pressure mode”, fuel gas obtained by gasifying liquefied gas is supplied into the combustion chamber of the high-pressure gas injection diesel engine by injection. As a specific example of the gas-firedengine 1 according to the present embodiment, the high-pressure gas injection diesel engine is a slow-speed two-stroke diesel engine with high-pressure gas injection (referred to as “SSD-GI” below). - Although the liquefied gas is liquefied natural gas (referred to as “LNG” below) and the fuel gas is natural gas obtained by gasifying the LNG in the following description, the engine and the device according to the present embodiment may be applied to an engine which uses liquefied gas such as liquefied petroleum gas (LPG) as fuel.
- The gas
fuel supply device 10 includes an LNG fuel system, a hydraulic system, and a control section (not shown). The LNG fuel system supplies the natural gas obtained by gasifying the LNG after boosting the pressure in areciprocating pump 20, into the combustion chamber of the high-pressure gas injection engine by injection. The hydraulic system supplies a hydraulic pressure to ahydraulic motor 50 that drives thereciprocating pump 20. The control section controls thehydraulic motor 50 or the like. Although one set of LNG fuel system and hydraulic system is shown in the configuration example in the drawing, the present invention is not limited thereto, and a plurality of sets coupled together may be employed. - The LNG fuel system includes the
reciprocating pump 20 driven by thehydraulic motor 50. Thereciprocating pump 20 is a pump that introduces the LNG having a substantially atmospheric pressure, boosts the pressure of the LNG to a desired pressure, and discharges the LNG. - An
LNG supply pipe 22 is connected to the discharge side of thereciprocating pump 20. TheLNG supply pipe 22 includes aheating unit 30, and an engine inlet gas pressure reducing valve (referred to as “gas pressure reducing valve” below) 40, which are sequentially arranged from the pump side. - The
heating unit 30 is a unit that heats and gasifies the boosted LNG supplied from thereciprocating pump 20. That is, the high-pressure LNG flowing into theheating unit 30 is heated within the unit to flow out as the natural gas obtained by gasifying the LNG. - A pressure sensor (not shown) is provided adjacent to an outlet of the
heating unit 30. A natural gas outlet pressure PV detected by the pressure sensor is input to the control section as a gas fuel outlet pressure. The control section adjusts the rotational speed of thehydraulic motor 50 described below so as to maintain the natural gas outlet pressure PV at a predefined constant pressure value. The control section may be provided integrally with a control section of theelectronic control unit 60 described below. - The natural gas supplied from the
heating unit 30 is adjusted to a desired pressure by the gaspressure reducing valve 40, and then supplied into the high-pressure combustion chamber by injection. That is, the injection (supply) pressure of the natural gas regulated by the gaspressure reducing valve 40 needs to be higher than the pressure within the combustion chamber so as to inject the natural gas into the combustion chamber which is compressed to a high pressure by a piston. An operation mode in which the natural gas is injected into the combustion chamber at high pressure as described above is called “high-pressure mode”. In the case of the SSD-GI, the injection pressure of the natural gas in the high-pressure mode is generally 150 to 300 bar. - The gas
pressure reducing valve 40 has a “low-pressure mode” in which the natural gas as gas fuel is supplied as the fuel of a gas-spark Otto-cycle engine in addition to the above “high-pressure mode”. The “low-pressure mode” is used when the gas fuel is supplied to a generator engine or the like that generates electricity for a vessel, and employs a lower pressure than that of the “high-pressure mode”. - The
LNG supply pipe 22 includes arecirculation line 23 that branches therefrom upstream of theheating unit 30. Therecirculation line 23 is a pipe line that branches the LNG boosted in thereciprocating pump 20 from the upstream side of theheating unit 30 into asuction drum 24. Arecirculation control valve 25 as a flow regulating valve is provided upstream of thesuction drum 24. AnLNG introduction pipe 21 connected to thesuction drum 24 is connected to an unillustrated LNG tank or the like. - Since the
recirculation line 23 is provided, the recirculation flow rate of the LNG flowing through therecirculation line 23 can be controlled by adjusting the opening degree of theflow regulating valve 25 so as to reduce the LNG flow rate in a low-speed region in which the rotational speed of thehydraulic motor 50 cannot be controlled or in time of emergency. - To be more specific, the recirculation flow rate is ensured by increasing the opening degree of the
recirculation control valve 25 in a low-speed region with small pump load, for example, as shown in the explanatory view inFIG. 4 . That is, the total flow rate of the LNG flowing through thereciprocating pump 20 is ensured by increasing the recirculation flow rate at an operational point OP with small pump load. Thehydraulic motor 50 is thereby maintained within a rotation number region in which thehydraulic motor 50 can be controlled. When the LNG rate is reduced in time of emergency, the supply to theheating unit 30 may be limited by increasing the opening degree of therecirculation control valve 25 to cause the LNG to bypass theheating unit 30 and thereby increase the recirculation flow rate. - The
suction drum 24 is an LNG container that collects the LNG branched and introduced from theLNG supply pipe 22, and returns the LNG to a recirculation suction section of thereciprocating pump 20. The recirculation flow rate of the LNG introduced into therecirculation line 23 is regulated by therecirculation control valve 25 that operates based on a control signal for the operational point OP output from the control section. The control signal for the operational point OP is an opening signal that defines the operational point output from the control section based on a setting point SP obtained from the number of rotations of the engine, and the natural gas outlet pressure PV detected by the pressure sensor. - The setting point SP in this case may employ a variable value, such as a highly-controllable pressure value of the gas
pressure reducing valve 40, in addition to the number of rotations of the engine, or may be a fixed value. - The hydraulic system in this case introduces a portion of hydraulic pressure held by the
electronic control unit 60, and supplies the hydraulic pressure to thehydraulic motor 50 that drives thereciprocating pump 20. That is, the hydraulic system includes a hydraulicoil introduction line 51 that introduces a portion of high-pressure hydraulic oil from ahydraulic oil line 61 of theelectronic control unit 60, supplies the high-pressure hydraulic oil to thehydraulic motor 50, and thereby drives thehydraulic motor 50, and a hydraulicoil return line 52 that returns the high-pressure hydraulic oil used for driving thehydraulic motor 50 to thehydraulic oil line 61. - The
hydraulic oil line 61 of theelectronic control unit 60 uses a portion of engine lubricant oil stored in acrankcase 62 as the high-pressure hydraulic oil. - The engine lubricant oil in the
crankcase 62 is supplied to afilter unit 65 by an electriclubricant oil pump 64 provided in alubricant oil line 63. After foreign matter is removed from the engine lubricant oil by thefilter unit 65, the pressure of the engine lubricant oil is boosted by anengine drive pump 66 or anelectric pump 67 to obtain the high-pressure hydraulic oil. The high-pressure hydraulic oil is thereby supplied to thehydraulic oil line 61. In this case, theelectric pump 67 described above is required at the time of engine start up. Theengine drive pump 66 is mainly used to supply the hydraulic pressure at the time of normal operation after the engine start up. - A
changeover valve block 68 that changes a pump suction direction and a pump discharge direction in reverse operation of the gas-firedengine 1 is provided between theengine drive pump 66 driven in the gas-firedengine 1 and thehydraulic oil line 61. - The hydraulic
oil introduction line 51 is a pipe line that branches from thehydraulic oil line 61 upstream of theelectronic control unit 60, and supplies a portion of the high-pressure hydraulic oil to thehydraulic motor 50. - The hydraulic
oil return line 52 is a pipe line that returns the high-pressure hydraulic oil used for driving thehydraulic motor 50 to thehydraulic oil line 61. Asub-storage tank 53 that temporarily stores the high-pressure hydraulic oil used for driving thehydraulic motor 50 is provided in the hydraulicoil return line 52. The hydraulic fluid stored in thesub-storage tank 53 is returned to thecrankcase 62 through the hydraulicoil return line 52 by operating an electricoil return pump 54. -
Reference numeral 55 in the drawing denotes a pipe line that connects the hydraulicoil introduction line 51 and thesub-storage tank 53, andreference numeral 56 denotes a check valve provided in thepipe line 55. Since thepipe line 55 and thecheck valve 56 are provided, the hydraulicoil introduction line 51 can be prevented from coming under negative pressure by sucking the hydraulic fluid from thesub-storage tank 53 in case of an emergency stop of the engine or the like. - As described above, in the gas
fuel supply device 10 according to the present embodiment, the pressure of the LNG is boosted by thereciprocating pump 20 driven by thehydraulic motor 50 by effectively using the high-pressure hydraulic oil of theelectronic control unit 60 provided in the gas-firedengine 1 without newly providing a hydraulic supply system (a hydraulic pump or the like) for driving thehydraulic motor 50. Accordingly, in the gasfuel supply device 10 according to the present embodiment, the number of additional devices can be minimized by commonly using the hydraulic facility of theelectronic control unit 60 in the hydraulic system required in supplying the LNG as engine fuel. - The gas-fired
engine 1 as described above can change the number of rotations of the engine to any number based on a vessel speed within a vessel. For example, the number of rotations of the engine increases with an increase in engine load. Thus, theengine drive pump 66 that supplies the high-pressure hydraulic oil to theelectronic control unit 60 also has a higher discharge rate and a higher hydraulic pressure. For thereciprocating pump 20 for boosting the pressure of liquefied gas in which a higher flow rate and a higher pressure are required when the consumption of gas fuel obtained by gasifying the LNG increases, the high-pressure hydraulic oil of theelectronic control unit 60 is a favorable hydraulic power source. - In other words, the rotational speed of the
hydraulic motor 50 that drives thereciprocating pump 20 can be controlled by performing capacity control (oil control) of theengine drive pump 66 that supplies the high-pressure hydraulic oil to theelectronic control unit 60, that is, by adjusting the discharge rate of theengine drive pump 66. It is thus not necessary to provide a speed reduction mechanism or control the number of rotations of an electric motor. In this case, a variable capacity pump such as a plunger pump may be employed as theengine drive pump 66, and the plunger inclination angle may be adjusted to control the discharge rate. - The LNG discharge rate of the
reciprocating pump 20 can be controlled by the number of rotations and the hydraulic pressure of thehydraulic motor 50. Accordingly, the LNG supply to theheating unit 30 can be easily controlled (increased or decreased) in conjunction with an increase or a decrease in the supply and the hydraulic pressure of the high-pressure hydraulic oil in association with variation in engine load. - The
reciprocating pump 20 driven by thehydraulic motor 50, and theengine drive pump 66 as a hydraulic pump unit that supplies the hydraulic pressure to thehydraulic motor 50 are connected together via the hydraulic pipes of the hydraulicoil introduction line 51 and the hydraulicoil return line 52. That is, thereciprocating pump 20 driven by thehydraulic motor 50 and theengine drive pump 66 as the hydraulic power supply source can be connected together by the hydraulicoil introduction line 51 and the hydraulicoil return line 52, and can be thereby mounted separately from each other. Thus, thereciprocating pump 20 having no electric device and no speed reduction mechanism can be easily installed in a gas hazardous area. - Since the hydraulic pressure is supplied from the main engine of a vessel, it is not necessary to drive a power-generating four-stroke engine having lower thermal efficiency than the main two-stroke engine so as to supply driving electricity to the separately-mounted hydraulic unit. Thus, the operating cost can be reduced.
- Next, a gas-fired engine according to a second embodiment of the present invention will be described based on
FIG. 2 . The same portions as those of the aforementioned embodiment are assigned the same reference numerals, and the detailed description is omitted. - A gas-fired
engine 1A according to the embodiment shown inFIG. 2 includes a gasfuel supply device 10A having a different configuration from that of the aforementioned embodiment. In the gasfuel supply device 10A, while the LNG fuel system has substantially the same configuration as that of the aforementioned embodiment, the hydraulic system that supplies the hydraulic pressure to thehydraulic motor 50 has a different configuration. - The hydraulic system in this case drives a
hydraulic pump 70 of the hydraulic pump unit that supplies the driving hydraulic pressure to thehydraulic motor 50 by effectively using exhaust gas of the gas-firedengine 1A. Thehydraulic pump 70 is a variable capacity pump that uses as a drive source anexhaust turbine 81 operated by extracting a portion of exhaust gas from an engine exhaust static-pressure pipe 80. For example, thehydraulic pump 70 is a plunger pump. - An exhaust gas
supply flow passage 82 that introduces a portion of the exhaust gas from the engine exhaust static-pressure pipe 80, and an exhaust gasdischarge flow passage 83 that guides the exhaust gas working in theexhaust turbine 81 to a funnel for release to the atmosphere are connected to theexhaust turbine 81. - An exhaust gas
flow control valve 84 is provided in the exhaust gassupply flow passage 82 so as to regulate the flow rate of the exhaust gas supplied to theexhaust turbine 81 when needed. An exhaust gasbypass flow passage 85 that branches from the exhaust gassupply flow passage 82 upstream of the exhaust gasflow control valve 84 is also provided in the exhaust gassupply flow passage 82. The exhaust gasbypass flow passage 85 is connected to the exhaust gasdischarge flow passage 83. A bypassflow regulating valve 86 and anorifice 87 are provided in the exhaust gas bypass flow passage. - The main stream of the exhaust gas discharged from the engine exhaust static-
pressure pipe 80 passes through a main exhaust gassupply flow passage 88 to be supplied to anexhaust turbine 89 a of aturbocharger 89. The exhaust gas main stream is guided to the funnel through a main exhaust gasdischarge flow passage 90 after driving theexhaust turbine 89 a. The above exhaust gasdischarge flow passage 83 is connected to the main exhaust gasdischarge flow passage 90. - In the
turbocharger 89, acompressor 89 b driven by a rotating shaft of theexhaust turbine 89 a suctions and compresses air within an engine chamber. The compressed air for aeration (scavenging) compressed by thecompressor 89 b is cooled in anair cooler 91 to increase the air density. The air is thereby supplied to anintake manifold 92. -
Reference numeral 93 in the drawing denotes a cylinder of the gas-firedengine 1A. Although the gas-firedengine 1A has six cylinders in the configuration example in the drawing, the present invention is not limited thereto. - Since the gas-fired
engine 1A effectively uses the exhaust gas to be released to the atmosphere as the hydraulic power supply source of the gasfuel supply device 10A, the hydraulic pressure can be supplied to thehydraulic motor 50 by operating thehydraulic pump 70. - The high-pressure hydraulic oil discharged from the
hydraulic pump 70 is supplied to thehydraulic motor 50 through a hydraulicoil introduction line 51A. The hydraulic fluid flowing into thesub-storage tank 53 after driving thehydraulic motor 50 is returned to a hydraulicfluid storage tank 59 by use of the electricoil return pump 54. - In the gas-fired
engine 1A according to the present embodiment, the gasfuel supply device 10A includes thehydraulic pump 70 of the hydraulic pump unit that supplies the driving hydraulic pressure to thehydraulic motor 50 from thehydraulic pump 70 driven by theexhaust turbine 81, theexhaust turbine 81 being operated by extracting a portion of the exhaust gas from the engine exhaust static-pressure pipe 80. Accordingly, thehydraulic pump 70 is driven by effectively using the exhaust gas which is generated in a larger amount with an increase in engine load. The pressure of the LNG can be boosted by thereciprocating pump 20 driven by the hydraulic motor. - In this case, when the engine load increases, the consumption of natural gas (engine fuel) obtained by gasifying the LNG increases, and the amount of exhaust gas also increases. Thus, a higher flow rate and a higher pressure are required for the LNG in the
reciprocating pump 20. For thereciprocating pump 20 for boosting the pressure of LNG as described above, thehydraulic pump 70 driven by theexhaust turbine 81 is a favorable hydraulic power supply source since variation in required fuel and variation in hydraulic pressure to be supplied to thehydraulic motor 50 that drives thereciprocating pump 20 on the fuel supply side show substantially the same tendency. - The hydraulic system according to the above embodiment can boost the pressure of the liquefied gas by the
reciprocating pump 20 driven by thehydraulic motor 50 with a minimum number of additional devices. - In the gas
fuel supply device 10A according to the aforementioned embodiment, thehydraulic pump 70 is preferably a variable capacity pump, and the unillustrated control section preferably adjusts the rotational speed of thehydraulic motor 50 by performing variable capacity control of thehydraulic pump 70 to maintain constant the gas fuel outlet pressure of the natural gas (gas fuel) to be supplied from the gaspressure reducing valve 40 to the gas-firedengine 1A. - By the variable capacity control as described above, the rotational speed of the
hydraulic motor 50 that drives thereciprocating pump 20 is adjusted by performing capacity control (oil control) of thehydraulic pump 70. It is thus not necessary to provide a speed reduction mechanism or control the rotation number of an electric motor. - As preferable variable capacity control in this case, for example, a swash plate pump may be employed as the hydraulic pump, and the opening degree of the exhaust gas
flow control valve 84 may be fixed and the angle of the swash plate may be appropriately adjusted to control the pump discharge rate. - The gas
fuel supply device 10A according to the above embodiment may also employ a modification in which thehydraulic pump 70 is a constant capacity pump, and the unillustrated control section adjusts the rotational speed of thehydraulic motor 50 by performing rotation number control of theexhaust turbine 81 to maintain constant the gas fuel outlet pressure at the gaspressure reducing valve 40. In this case, the number of rotations of the exhaust turbine may be controlled by providing an exhaust gas flow control valve, that is, theflow control valve 84 whose opening degree is adjustable on the inlet side of theexhaust turbine 81, and appropriately adjusting the valve opening degree of theflow control valve 84. - In this case, the rotational speed of the
hydraulic motor 50 that drives thereciprocating pump 20 can be also adjusted by controlling the number of rotations of the exhaust turbine on the drive side. It is thus not necessary to provide a speed reduction mechanism or control the rotation number of an electric motor. - The
reciprocating pump 20 driven by thehydraulic motor 50, and the hydraulic pump unit (the hydraulic pump 70) that supplies the hydraulic pressure to thehydraulic motor 50 can be connected together via the hydraulic pipe, and can be thereby mounted separately from each other. Thus, thereciprocating pump 20 having no electric device and no speed reduction mechanism can be easily installed in a gas hazardous area. - Since the exhaust gas energy discharged from the main engine of a vessel is effectively used as the hydraulic pressure, it is not necessary to drive a power-generating four-stroke engine having lower thermal efficiency than the main two-stroke engine so as to supply driving electricity to the separately-mounted hydraulic unit. Thus, the operating cost can be reduced.
- Next, a gas-fired engine according to a third embodiment of the present invention will be described based on
FIG. 3 . The same portions as those of the aforementioned embodiment are assigned the same reference numerals, and the detailed description is omitted. - A gas-fired
engine 1B according to the embodiment shown inFIG. 3 includes a gasfuel supply device 10B having a different configuration from that of the aforementioned embodiment. In the gasfuel supply device 10B, while the LNG fuel system has substantially the same configuration as that of the aforementioned embodiment, the hydraulic system that supplies the hydraulic pressure to thehydraulic motor 50 has a different configuration. - The hydraulic system in this case drives a
hydraulic pump 70A of the hydraulic pump unit that supplies the driving hydraulic pressure to thehydraulic motor 50 by effectively using exhaust gas of the gas-firedengine 1B. Thehydraulic pump 70A is a variable capacity pump that is driven by the rotating shaft of theexhaust turbine 89 a of theturbocharger 89, theturbocharger 89 being operated with the exhaust gas discharged from the engine exhaust static-pressure pipe 80. For example, thehydraulic pump 70A is a plunger pump. - The main exhaust gas
supply flow passage 88 that introduces the exhaust gas from the engine exhaust static-pressure pipe 80, and the main exhaust gasdischarge flow passage 90 that guides the exhaust gas working in theexhaust turbine 89 a to the funnel for release to the atmosphere are connected to theexhaust turbine 89 a. - The exhaust gas discharged from the engine exhaust static-
pressure pipe 80 is supplied to theexhaust turbine 89 a of theturbocharger 89 through the main exhaust gassupply flow passage 88. The exhaust gas stream is guided to the funnel through the main exhaust gasdischarge flow passage 90 after driving theexhaust turbine 89 a. - In the
turbocharger 89, thecompressor 89 b driven by the rotating shaft of theexhaust turbine 89 a suctions and compresses air within the engine chamber. The compressed air for aeration (scavenging) compressed by thecompressor 89 b is cooled in theair cooler 91 to increase the air density. The air is thereby supplied to theintake manifold 92. -
Reference numeral 93 in the drawing denotes a cylinder of the gas-firedengine 1B. Although the gas-firedengine 1B has six cylinders in the configuration example in the drawing, the present invention is not limited thereto. - The gas-fired
engine 1B effectively uses the exhaust gas to be released to the atmosphere as the hydraulic power supply source of the gasfuel supply device 10B. Accordingly, the hydraulic pressure can be supplied to thehydraulic motor 50 by operating thehydraulic pump 70A by the shaft drive of theexhaust turbine 89 a of theturbocharger 89, and boosting the pressure of the hydraulic fluid introduced from the hydraulicfluid storage tank 59. - The high-pressure hydraulic oil discharged from the
hydraulic pump 70A is supplied to thehydraulic motor 50 through the hydraulicoil introduction line 51A. The hydraulic fluid flowing into thesub-storage tank 53 after driving thehydraulic motor 50 is returned to the hydraulicfluid storage tank 59 by use of the electricoil return pump 54. - In the gas-fired
engine 1B according to the present embodiment, the gasfuel supply device 10B includes thehydraulic pump 70A of the hydraulic pump unit that supplies the driving hydraulic pressure to thehydraulic motor 50 from thehydraulic pump 70A driven by theexhaust turbine 89 a, theexhaust turbine 89 a being operated by introducing the exhaust gas from the engine exhaust static-pressure pipe 80. Accordingly, thehydraulic pump 70A is driven by effectively using the exhaust gas which is generated in a larger amount with an increase in engine load. The pressure of the LNG can be boosted by thereciprocating pump 20 driven by the hydraulic motor. - In this case, when the engine load increases, the consumption of natural gas (engine fuel) obtained by gasifying the LNG increases, and the amount of exhaust gas also increases. Thus, a higher flow rate and a higher pressure are required for the LNG in the
reciprocating pump 20. For thereciprocating pump 20 for boosting the pressure of LNG as described above, thehydraulic pump 70A driven by theexhaust turbine 89 a is a favorable hydraulic power supply source since variation in required fuel and variation in hydraulic pressure to be supplied to thehydraulic motor 50 that drives thereciprocating pump 20 on the fuel supply side show substantially the same tendency. - The hydraulic system according to the above embodiment can boost the pressure of the liquefied gas by the
reciprocating pump 20 driven by thehydraulic motor 50 with a minimum number of additional devices. - In the gas
fuel supply device 10B according to the aforementioned embodiment, thehydraulic pump 70A is preferably a variable capacity pump, and the unillustrated control section preferably adjusts the rotational speed of thehydraulic motor 50 by performing variable capacity control of thehydraulic pump 70A to maintain constant the gas fuel outlet pressure of the natural gas (gas fuel) to be supplied from the gaspressure reducing valve 40 to the gas-firedengine 1B. - By the variable capacity control as described above, the rotational speed of the
hydraulic motor 50 that drives thereciprocating pump 20 is adjusted by performing capacity control (oil control) of thehydraulic pump 70A. It is thus not necessary to provide a speed reduction mechanism or control the rotation number of an electric motor. - As preferable variable capacity control in this case, for example, a swash plate pump may be employed as the hydraulic pump, and the angle of the swash plate may be appropriately adjusted to control the pump discharge rate.
- In this case, the rotational speed of the
hydraulic motor 50 that drives thereciprocating pump 20 can be also adjusted by controlling the number of rotations of the exhaust turbine on the drive side. It is thus not necessary to provide a speed reduction mechanism or control the rotation number of an electric motor. - The
reciprocating pump 20 driven by thehydraulic motor 50, and the hydraulic pump unit (thehydraulic pump 70A) that supplies the hydraulic pressure to thehydraulic motor 50 can be connected together via the hydraulic pipe, and can be thereby mounted separately from each other. Thus, thereciprocating pump 20 having no electric device and no speed reduction mechanism can be easily installed in a gas hazardous area. - Since the exhaust gas energy discharged from the main engine of a vessel is effectively used as the hydraulic pressure, it is not necessary to drive a power-generating four-stroke engine having lower thermal efficiency than the main two-stroke engine so as to supply driving electricity to the separately-mounted hydraulic unit. Thus, the operating cost can be reduced.
- As described above, the gas-fired
engines reciprocating pump 20 that is driven by the hydraulic motor and can be easily arranged in a gas hazardous area in the high-pressure gas injection diesel engine, such as an electronically-controlled slow-speed two-stroke diesel engine with high-pressure gas injection, which supplies high-pressure natural gas as fuel into the combustion chamber. - Since the hydraulic pressure is supplied from the
electronic control unit 60 on the engine side, it is not necessary to install a new hydraulic unit for supplying the hydraulic pressure to thehydraulic motor 50 that drives the reciprocating pump. Consequently, the installation space and the cost of the gas-firedengine 1 can be reduced. Especially in a vessel with limited space, the space within the vessel can be effectively used by increasing a cargo space or the like. - In the method for driving the
hydraulic pumps exhaust turbine 81 or theturbocharger 89 operated with the exhaust gas as in the gas-firedengines hydraulic motor 50 for driving the reciprocating pump can be minimized. Consequently, the installation space and the cost of the gas-firedengines - The present invention is not limited to the aforementioned embodiments, and may be changed as appropriate without departing from the scope.
-
- 1,1A,1B Gas-fired engine
- 10,10A,10B Gas fuel supply device
- 20 Reciprocating pump
- 21 LNG introduction pipe
- 22 LNG supply pipe
- 23 Recirculation line
- 24 Suction drum
- 25 Recirculation control valve
- 30 Heating unit
- 40 Engine inlet gas pressure reducing valve (gas pressure reducing valve)
- 50 Hydraulic motor
- 51,51A Hydraulic oil introduction line
- 52 Hydraulic oil return line
- 53 Sub-storage tank
- 54 Oil return pump
- 59 Hydraulic fluid storage tank
- 60 Electronic control unit
- 61 Hydraulic oil line
- 62 Crankcase
- 63 Lubricant oil line
- 64 Lubricant oil pump
- 65 Filter unit
- 66 Engine drive pump
- 67 Electric pump
- 70,70A Hydraulic pump
- 80 Engine exhaust static-pressure pipe
- 81 Exhaust turbine
- 82 Exhaust gas supply flow passage
- 83 Exhaust gas discharge flow passage
- 84 Exhaust gas flow control valve
- 88 Main exhaust gas supply flow passage
- 89 Turbocharger
- 89 a Exhaust turbine
- 89 b Compressor
- 90 Main exhaust gas discharge flow passage
- 91 Air cooler
- 92 Intake manifold
- OP Operational point
- RCV Recirculation control valve
Claims (12)
1. A gas-fired engine for a high-pressure gas injection engine comprising an electronic control unit that drives an engine by controlling high-pressure hydraulic oil by a controller and an electromagnetic valve, and a gas fuel supply device that boosts a pressure of liquefied gas as fuel gas to a high pressure and performs supply into a combustion chamber by injection,
wherein the gas fuel supply device includes:
a reciprocating pump that is driven by a hydraulic motor to boost a pressure of liquefied gas introduced thereto to a desired pressure and discharge the liquefied gas;
a hydraulic oil introduction line that introduces a portion of the high-pressure hydraulic oil from a hydraulic oil line of the electronic control unit, supplies the high-pressure hydraulic oil to the hydraulic motor, and thereby drives the hydraulic motor;
a heating unit that heats and gasifies the boosted liquefied gas supplied from the reciprocating pump; and
a control section that adjusts a rotational speed of the hydraulic motor by controlling oil supplied from the hydraulic pump to maintain constant a gas fuel outlet pressure of the heating unit.
2. The gas-fired engine according to claim 1 , wherein the rotational speed of the hydraulic motor is controlled by adjusting a discharge rate of a hydraulic pump that supplies the high-pressure hydraulic oil to the electronic control unit.
3. A gas-fired engine for a high-pressure gas injection engine comprising a gas fuel supply device that boosts a pressure of liquefied gas as fuel gas to a high pressure and performs supply into a combustion chamber by injection,
wherein the gas fuel supply device includes:
a reciprocating pump that is driven by a hydraulic motor to boost a pressure of liquefied gas introduced thereto to a desired pressure and discharge the liquefied gas;
a hydraulic pump unit that supplies a driving hydraulic pressure to the hydraulic motor from a hydraulic pump driven by a rotating shaft of an exhaust turbine, the exhaust turbine being operated by extracting a portion of exhaust gas from an engine exhaust static-pressure pipe;
a heating unit that heats and gasifies the boosted liquefied gas supplied from the reciprocating pump; and
a control section that adjusts a rotational speed of the hydraulic motor by controlling oil supplied from the hydraulic pump to maintain constant a gas fuel outlet pressure of the heating unit.
4. The gas-fired engine according to claim 3 , further comprising an engine inlet gas pressure reducing valve that regulates a pressure of gas fuel to be injected into the combustion chamber.
5. A gas-fired engine for a high-pressure gas injection engine comprising a turbocharger, and a gas fuel supply device that boosts a pressure of liquefied gas as fuel gas to a high pressure and preforms supply into a combustion chamber by injection,
wherein the gas fuel supply device includes:
a reciprocating pump that is driven by a hydraulic motor to boost a pressure of liquefied gas introduced thereto to a desired pressure and discharge the liquefied gas;
a hydraulic pump unit that supplies a driving hydraulic pressure to the hydraulic motor from a hydraulic pump driven by a rotating shaft of the turbocharger;
a heating unit that heats and gasifies the boosted liquefied gas supplied from the reciprocating pump; and
a control section that adjusts a rotational speed of the hydraulic motor by controlling oil supplied from the hydraulic pump to maintain constant a gas fuel outlet pressure of the heating unit.
6. The gas-fired engine according to claim 5 , further comprising an engine inlet gas pressure reducing valve that regulates a pressure of gas fuel to be injected into the combustion chamber.
7. The gas-fired engine according to claim 3 , wherein in the gas fuel supply device, the hydraulic pump is a variable capacity pump, and the control section adjusts the rotational speed of the hydraulic motor by variable capacity control of the hydraulic pump to maintain constant the gas fuel outlet pressure.
8. The gas-fired engine according to claim 4 , wherein in the gas fuel supply device, the hydraulic pump is a variable capacity pump, and control section adjusts the rotational speed of the hydraulic motor by variable capacity control of the hydraulic pump to maintain constant the gas fuel outlet pressure.
9. The gas-fired engine according to claim 5 , wherein in the gas fuel supply device, the hydraulic pump is a variable capacity pump, and the control section adjusts the rotational speed of the hydraulic motor by variable capacity control of the hydraulic pump to maintain constant the gas fuel outlet pressure.
10. The gas-fired engine according to claim 6 , wherein in the gas fuel supply device, the hydraulic pump is a variable capacity pump, and the control section adjusts the rotational speed of the hydraulic motor by variable capacity control of the hydraulic pump to maintain constant the gas fuel outlet pressure.
11. The gas-fired engine according to claim 3 , wherein in the gas fuel supply device, the hydraulic pump is a constant capacity pump, and the control section adjusts the rotational speed of the hydraulic motor by rotation number control of the exhaust turbine to maintain constant the gas fuel outlet pressure.
12. The gas-fired engine according to claim 4 , wherein in the gas fuel supply device, the hydraulic pump is a variable capacity pump, and the control section adjusts the rotational speed of the hydraulic motor by variable capacity control of the hydraulic pump to maintain constant the gas fuel outlet pressure.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US14/735,633 US20150275824A1 (en) | 2011-03-31 | 2015-06-10 | Gas-fired engine |
Applications Claiming Priority (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2011081193A JP5808128B2 (en) | 2011-03-31 | 2011-03-31 | Gas fired engine |
JP2011-081193 | 2011-03-31 | ||
PCT/JP2012/056695 WO2012132931A1 (en) | 2011-03-31 | 2012-03-15 | Gas-fired engine |
US201313985065A | 2013-08-13 | 2013-08-13 | |
US14/735,633 US20150275824A1 (en) | 2011-03-31 | 2015-06-10 | Gas-fired engine |
Related Parent Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2012/056695 Division WO2012132931A1 (en) | 2011-03-31 | 2012-03-15 | Gas-fired engine |
US13/985,065 Division US9169769B2 (en) | 2011-03-31 | 2012-03-15 | Gas-fired engine |
Publications (1)
Publication Number | Publication Date |
---|---|
US20150275824A1 true US20150275824A1 (en) | 2015-10-01 |
Family
ID=46930666
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/985,065 Expired - Fee Related US9169769B2 (en) | 2011-03-31 | 2012-03-15 | Gas-fired engine |
US14/735,633 Abandoned US20150275824A1 (en) | 2011-03-31 | 2015-06-10 | Gas-fired engine |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/985,065 Expired - Fee Related US9169769B2 (en) | 2011-03-31 | 2012-03-15 | Gas-fired engine |
Country Status (5)
Country | Link |
---|---|
US (2) | US9169769B2 (en) |
JP (1) | JP5808128B2 (en) |
KR (3) | KR101494109B1 (en) |
CN (2) | CN103080525B (en) |
WO (1) | WO2012132931A1 (en) |
Families Citing this family (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102010031033A1 (en) * | 2010-07-07 | 2012-01-12 | Robert Bosch Gmbh | Device as well as vehicle or work machine |
KR101386543B1 (en) | 2012-10-24 | 2014-04-18 | 대우조선해양 주식회사 | System for treating boil-off gas for a ship |
KR101398357B1 (en) | 2013-04-24 | 2014-05-23 | 현대중공업 주식회사 | Device for driving high pressure pump and fuel gas supply system of liquefied natural gas |
KR101640768B1 (en) * | 2013-06-26 | 2016-07-29 | 대우조선해양 주식회사 | Method for building a ship |
US9751606B2 (en) * | 2013-09-17 | 2017-09-05 | Daewoo Shipbuilding & Marine Engineerig Co., Ltd. | Apparatus and method for transferring inflammable material on marine structure |
US9745922B2 (en) * | 2013-09-17 | 2017-08-29 | Daewoo Shipbuilding & Marine Engineering Co., Ltd. | Apparatus and method for supplying fuel to engine of ship |
US9151248B2 (en) | 2013-09-17 | 2015-10-06 | Daewoo Shipbuilding & Marine Engineering Co., Ltd. | Apparatus and method for transferring inflammable material on marine structure |
WO2015068949A1 (en) * | 2013-11-07 | 2015-05-14 | Daewoo Shipbuilding & Marine Engineering Co., Ltd. | Apparatus and method for supplying fuel to engine of ship |
JP6285715B2 (en) * | 2013-12-27 | 2018-02-28 | 川崎重工業株式会社 | Ship fuel supply system |
JP5848375B2 (en) * | 2014-01-30 | 2016-01-27 | 三井造船株式会社 | Fuel gas supply device |
JP5778849B1 (en) * | 2014-12-22 | 2015-09-16 | 三井造船株式会社 | Power equipment |
JP6012810B1 (en) * | 2015-04-30 | 2016-10-25 | 三井造船株式会社 | Supercharger surplus power recovery device for internal combustion engine |
JP6620327B2 (en) * | 2015-09-03 | 2019-12-18 | 株式会社三井E&Sマシナリー | LIQUID GAS PRESSURE DEVICE, LIQUID GAS PRESSURE METHOD, AND FUEL SUPPLY DEVICE |
JP6832173B2 (en) * | 2017-01-26 | 2021-02-24 | 本田技研工業株式会社 | Fuel supply device |
DK179683B1 (en) * | 2017-09-04 | 2019-03-20 | MAN Energy Solutions | A large two-stroke compression-ignited internal combustion engine with dual fuel systems |
CN107947641A (en) * | 2017-12-27 | 2018-04-20 | 广州威能机电有限公司 | Thermal current utilizes device and thermo-electric generation system |
DK181415B1 (en) | 2022-11-04 | 2023-10-25 | Man Energy Solutions Filial Af Man Energy Solutions Se Tyskland | A large turbocharged two-stroke uniflow crosshead internal combustion engine and method for operating such engine |
CN115596549B (en) * | 2022-12-08 | 2023-03-10 | 常州柯林电子科技技术有限公司 | Natural gas combustion hybrid variable frequency motor assembly and working method thereof |
US11946679B1 (en) * | 2022-12-23 | 2024-04-02 | Jay Stephen Kaufman | Exhaust gas heat recovery from cryo-compression engines with cogeneration of cryo-working fluid |
Family Cites Families (34)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2042541C3 (en) * | 1970-08-27 | 1973-09-27 | Robert Bosch Gmbh, 7000 Stuttgart | Fuel injection system for vehicle gas turbines |
JPS6245923A (en) * | 1985-08-22 | 1987-02-27 | Mitsubishi Heavy Ind Ltd | Hydraulic power source device with internal combustion engine |
DE3532938C1 (en) | 1985-09-14 | 1986-09-18 | M.A.N.-B & W Diesel GmbH, 8900 Augsburg | Internal combustion engine charged by means of an exhaust gas turbocharger with an exhaust gas excess energy conversion device |
JPH05215233A (en) | 1992-02-05 | 1993-08-24 | Toyota Autom Loom Works Ltd | Engine vehicle equipped with variable displacement hydraulic pump for variable speed |
JPH0814316B2 (en) | 1992-09-17 | 1996-02-14 | 内田油圧機器工業 株式会社 | How to start a hydraulic motor installed in a closed hydraulic circuit |
JPH07237700A (en) * | 1994-02-27 | 1995-09-12 | Mitsubishi Heavy Ind Ltd | Loading arm |
JPH07277015A (en) | 1994-04-04 | 1995-10-24 | Iseki & Co Ltd | Hydraulic continuously variable transmission |
JP3019718B2 (en) | 1994-05-24 | 2000-03-13 | トヨタ自動車株式会社 | Hydraulic drive fan controller |
US5499615A (en) * | 1994-10-28 | 1996-03-19 | Caterpillar Inc. | Direct injection propane fuel system for diesel engine applications |
JPH09151912A (en) | 1995-12-01 | 1997-06-10 | Miyata Kogyo Kk | Hydraulically driven traveling mechanical device driven under explosive atmosphere |
DK174242B1 (en) | 1996-01-15 | 2002-10-14 | Man B & W Diesel As | A method of controlling the fuel supply to a diesel engine capable of supplying fuel oil and fuel gas with high pressure injection boats, and a high pressure gas injection engine of the diesel type. |
US5884488A (en) * | 1997-11-07 | 1999-03-23 | Westport Research Inc. | High pressure fuel supply system for natural gas vehicles |
US6659730B2 (en) * | 1997-11-07 | 2003-12-09 | Westport Research Inc. | High pressure pump system for supplying a cryogenic fluid from a storage tank |
JPH11241660A (en) * | 1998-02-25 | 1999-09-07 | Isuzu Motors Ltd | Injector assembling method for fuel injection system |
JP3850568B2 (en) | 1998-12-07 | 2006-11-29 | カヤバ工業株式会社 | HST vehicle control mechanism |
EP1144825B1 (en) * | 1999-01-21 | 2003-09-03 | Caterpillar Inc. | Engine with fluid sub-systems |
US6460510B1 (en) * | 2000-05-30 | 2002-10-08 | Robert H. Breeden | Pump assembly and method |
JP2002168201A (en) * | 2000-11-28 | 2002-06-14 | Komatsu Ltd | Engine driven hydraulic system |
US6640556B2 (en) * | 2001-09-19 | 2003-11-04 | Westport Research Inc. | Method and apparatus for pumping a cryogenic fluid from a storage tank |
JP3712661B2 (en) | 2001-12-06 | 2005-11-02 | 本田技研工業株式会社 | Control device for internal combustion engine |
US6817344B2 (en) * | 2002-12-30 | 2004-11-16 | Caterpillar Inc | Fuel supply system |
US6918243B2 (en) * | 2003-05-19 | 2005-07-19 | The Boeing Company | Bi-propellant injector with flame-holding zone igniter |
JP2005009432A (en) * | 2003-06-20 | 2005-01-13 | Nissan Diesel Motor Co Ltd | Fuel pressurizing device for cylinder injection type gas fuel engine |
JP2006283736A (en) * | 2005-04-05 | 2006-10-19 | Tokyo Gas Co Ltd | Self-driving type pump for liquefied gas |
JP4176742B2 (en) | 2005-06-14 | 2008-11-05 | 三菱重工業株式会社 | Hydraulic pressure supply device for internal combustion engine |
JP2007146708A (en) | 2005-11-25 | 2007-06-14 | Toyota Motor Corp | Internal combustion engine and intake valve control device for internal combustion engine |
KR101238728B1 (en) * | 2006-04-12 | 2013-03-05 | 맨 디젤 앤드 터보 필리얼 아프 맨 디젤 앤드 터보 에스이 티스크랜드 | A large turbocharged diesel engine with energy recovery arrangement |
JP5117828B2 (en) * | 2007-11-21 | 2013-01-16 | リョウコウエンジニアリング株式会社 | Drive device |
JP5046998B2 (en) * | 2008-02-26 | 2012-10-10 | 三菱重工業株式会社 | Liquefied gas storage facility and ship or marine structure using the same |
CN201354692Y (en) * | 2008-12-18 | 2009-12-02 | 东风汽车公司 | Vehicle-borne liquefied natural gas engine gas supply device with liquid booster pump |
JP5249866B2 (en) | 2009-06-25 | 2013-07-31 | 三菱重工業株式会社 | Engine exhaust energy recovery device |
JP2011057048A (en) * | 2009-09-09 | 2011-03-24 | Shin Kurushima Dockyard Co Ltd | Structure for arranging ballast water processing apparatus in tanker |
JP5448873B2 (en) | 2010-01-21 | 2014-03-19 | 三菱重工業株式会社 | ENGINE EXHAUST ENERGY RECOVERY DEVICE, SHIP HAVING THE SAME, POWER GENERATION PLANT HAVING THE SAME, ENGINE EXHAUST ENERGY RECOVERY DEVICE CONTROL DEVICE AND ENGINE EXHAUST ENERGY RECOVERY DEVICE CONTROL METHOD |
JP7068912B2 (en) * | 2018-04-25 | 2022-05-17 | 三菱電機株式会社 | Information processing equipment, equipment, defect analysis system, defect analysis method and program |
-
2011
- 2011-03-31 JP JP2011081193A patent/JP5808128B2/en active Active
-
2012
- 2012-03-15 KR KR1020137003635A patent/KR101494109B1/en active IP Right Grant
- 2012-03-15 CN CN201280002387.3A patent/CN103080525B/en active Active
- 2012-03-15 CN CN201510067405.1A patent/CN104727982B/en active Active
- 2012-03-15 KR KR1020157002736A patent/KR101600763B1/en active IP Right Grant
- 2012-03-15 KR KR1020147021429A patent/KR20140108720A/en active Search and Examination
- 2012-03-15 US US13/985,065 patent/US9169769B2/en not_active Expired - Fee Related
- 2012-03-15 WO PCT/JP2012/056695 patent/WO2012132931A1/en active Application Filing
-
2015
- 2015-06-10 US US14/735,633 patent/US20150275824A1/en not_active Abandoned
Also Published As
Publication number | Publication date |
---|---|
KR101494109B1 (en) | 2015-02-16 |
CN103080525B (en) | 2016-04-13 |
US9169769B2 (en) | 2015-10-27 |
CN103080525A (en) | 2013-05-01 |
KR101600763B1 (en) | 2016-03-09 |
WO2012132931A1 (en) | 2012-10-04 |
US20130312408A1 (en) | 2013-11-28 |
CN104727982B (en) | 2017-08-11 |
JP2012215128A (en) | 2012-11-08 |
KR20130054345A (en) | 2013-05-24 |
JP5808128B2 (en) | 2015-11-10 |
KR20140108720A (en) | 2014-09-12 |
CN104727982A (en) | 2015-06-24 |
KR20150024439A (en) | 2015-03-06 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US9169769B2 (en) | Gas-fired engine | |
EP2679795B1 (en) | Gas fuel supply device, high-pressure gas injection diesel engine, and liquefied gas fuel supply method for high-pressure gas injection diesel engine | |
EP1198663B1 (en) | High-pressure gas-turbine plant using high-pressure piston-type compressor | |
JP6902066B2 (en) | Fuel or lubrication pump for large 2-stroke compression ignition internal combustion engines | |
JP5832616B2 (en) | Turbocharged large low-speed two-stroke internal combustion engine with dual fuel supply system | |
EA015281B1 (en) | Gas turbine plant | |
KR102058380B1 (en) | A large two-stroke compression-ignited internal combustion engine with dual fuel systems | |
KR20170134213A (en) | Fuel supply system for a large two-stroke compression-ignited high-pressure gas injection internal combustion engine | |
KR20220138816A (en) | Method and large turbocharged two-stroke internal combustion engine for delivering mechanical energy and pressurized gas | |
JP5965019B1 (en) | Fuel supply device | |
JP5908056B2 (en) | Gas fired engine | |
JP6038225B2 (en) | Gas fired engine | |
JP2021011869A (en) | Gas fuel supply system and method of operating gas fuel supply system | |
KR101739440B1 (en) | Powering apparatus | |
CN110832179B (en) | Supercharger residual power recovery device for internal combustion engine, and ship | |
KR20220056142A (en) | Exhaust gas recirculation system and ship including the same | |
SU1544999A1 (en) | Four-stroke ic-engine |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STCB | Information on status: application discontinuation |
Free format text: EXPRESSLY ABANDONED -- DURING EXAMINATION |