JP2020076392A - EGR unit and engine system - Google Patents

EGR unit and engine system Download PDF

Info

Publication number
JP2020076392A
JP2020076392A JP2018211689A JP2018211689A JP2020076392A JP 2020076392 A JP2020076392 A JP 2020076392A JP 2018211689 A JP2018211689 A JP 2018211689A JP 2018211689 A JP2018211689 A JP 2018211689A JP 2020076392 A JP2020076392 A JP 2020076392A
Authority
JP
Japan
Prior art keywords
egr
exhaust gas
blower
scavenging
passage
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.)
Granted
Application number
JP2018211689A
Other languages
Japanese (ja)
Other versions
JP6550520B1 (en
Inventor
郁美 大西
Ikumi Onishi
郁美 大西
進士 仲尾
Shinji Nakao
進士 仲尾
西山　徹
Toru Nishiyama
徹 西山
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kawasaki Heavy Industries Ltd
Original Assignee
Kawasaki Heavy Industries Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Kawasaki Heavy Industries Ltd filed Critical Kawasaki Heavy Industries Ltd
Priority to JP2018211689A priority Critical patent/JP6550520B1/en
Application granted granted Critical
Publication of JP6550520B1 publication Critical patent/JP6550520B1/en
Priority to KR1020190132953A priority patent/KR102162893B1/en
Priority to CN201911077444.4A priority patent/CN111173654B/en
Publication of JP2020076392A publication Critical patent/JP2020076392A/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

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
    • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
    • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
    • 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
    • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
    • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
    • F02M26/34—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories with compressors, turbines or the like in the recirculation passage
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B25/00—Engines characterised by using fresh charge for scavenging cylinders
    • F02B25/02—Engines characterised by using fresh charge for scavenging cylinders using unidirectional scavenging
    • F02B25/04—Engines having ports both in cylinder head and in cylinder wall near bottom of piston stroke
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/0025—Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
    • F02D41/0047—Controlling exhaust gas recirculation [EGR]
    • F02D41/0065—Specific aspects of external EGR control
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/0025—Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
    • F02D41/0047—Controlling exhaust gas recirculation [EGR]
    • F02D41/0077—Control of the EGR valve or actuator, e.g. duty cycle, closed loop control of position
    • 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
    • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
    • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
    • F02M26/35—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories with means for cleaning or treating the recirculated gases, e.g. catalysts, condensate traps, particle filters or heaters
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B75/00—Other engines
    • F02B75/02—Engines characterised by their cycles, e.g. six-stroke
    • F02B2075/022—Engines characterised by their cycles, e.g. six-stroke having less than six strokes per cycle
    • F02B2075/025—Engines characterised by their cycles, e.g. six-stroke having less than six strokes per cycle two
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/12—Improving ICE efficiencies

Abstract

To provide an EGR unit which can allow a minute amount of scavenging air to flow in an EGR flow passage when the EGR blower is stopped during the operation of an engine.SOLUTION: An EGR unit 50 which is provided in a marine 2-cycle engine 10 and which supplies an exhaust gas from an exhaust gas flow passage 20 to a scavenging air flow passage 40 whose pressure is higher than that of the exhaust gas flow passage includes: an EGR flow passage for connecting the exhaust gas flow passage and the scavenging air flow passage; and an EGR blower 53 provided in the EGR flow passage. The EGR flow passage allows scavenging air to flow in from an outlet of the EGR flow passage by utilizing a pressure difference between the exhaust gas flow passage and the scavenging air flow passage when the EGR blower is stopped, and the exhaust gas in the EGR flow passage is exhausted into the exhaust gas flow passage by the inflow scavenging air. When the EGR blower is stopped during the operation of the engine, the scavenging air leaks and flows in a gap between members moving relatively out of a plurality of members which the EGR blower has.SELECTED DRAWING: Figure 1

Description

本発明は、ＥＧＲユニット及びエンジンシステムに関する。   The present invention relates to an EGR unit and an engine system.

近年、舶用エンジンに対する排ガス規制が強化されており、ＩＭＯ（国際海事機関）は、２０１６年１月１日以降に建造起工された船舶がＥＣＡ（排出規制海域）を航行する場合に、１次規制値に比してＮＯｘ排出量を８０％削減した３次規制値を適用する。この規制への対策の一つが排ガス再循環（Exhaust Gas Recirculation；ＥＧＲ）ユニットの設置である。ＥＧＲユニットは、エンジンから排出された排ガスを、ＥＧＲ流路を介して掃気流路に供給する。排ガスを掃気流路に供給する（ＥＧＲを行う）ことにより、掃気の酸素濃度が下がり、シリンダ内での燃焼時間が長くなる結果、燃焼最高温度が低下し、ＮＯｘの排出量を抑制することができる。ただし、ＥＧＲを行うと燃費が悪化することから、ＥＣＡ内ではＥＧＲブロワを運転してＥＧＲを行う一方、ＥＣＡ外ではＥＧＲブロワを停止してＥＧＲを行わないとする運用が一般的である。また、エンジンの低負荷時など、ＮＯｘ排出量が少ない負荷領域にあるときにもＥＧＲブロワを停止する。   In recent years, exhaust gas regulations for marine engines have been tightened, and the IMO (International Maritime Organization) has set the first regulation when ships constructed and constructed on or after January 1, 2016 sail in ECA (Emission Control Area). Apply the third regulation value that reduces NOx emissions by 80% compared to the value. One of the measures against this regulation is the installation of an exhaust gas recirculation (EGR) unit. The EGR unit supplies the exhaust gas discharged from the engine to the scavenging passage via the EGR passage. By supplying the exhaust gas to the scavenging flow path (performing EGR), the oxygen concentration of the scavenging gas is lowered and the combustion time in the cylinder is lengthened. As a result, the maximum combustion temperature is lowered and the amount of NOx emission can be suppressed. it can. However, since fuel consumption deteriorates when EGR is performed, it is common to operate the EGR blower inside the ECA to perform EGR, while stopping the EGR blower outside the ECA so that EGR is not performed. The EGR blower is also stopped when the engine is under a low load, such as in a load range where the NOx emission amount is small.

ここで、従来のＥＧＲユニットでは、ＥＧＲ流路に排ガスを圧送するＥＧＲブロワが設けられているとともに、ＥＧＲブロワが停止したときに閉じられる開閉弁又は逆流を防ぐ逆止弁が設けられている（例えば、特許文献１参照）。このようにＥＧＲ流路に開閉弁や逆止弁を設けることにより、ＥＧＲブロワが停止したときに掃気流路からＥＧＲ流路に掃気が流入するのを防ぐことができる。   Here, in the conventional EGR unit, an EGR blower that pressure-feeds exhaust gas is provided in the EGR flow path, and an on-off valve that is closed when the EGR blower stops or a check valve that prevents backflow is provided ( For example, see Patent Document 1). By providing the on-off valve and the check valve in the EGR passage in this way, it is possible to prevent the scavenging air from flowing into the EGR passage from the scavenging passage when the EGR blower is stopped.

特開２０１４−１２２５７５号公報JP, 2014-122575, A

しかしながら、ＥＧＲ流路内に排ガスが残ったままにしておくと、ＥＧＲ流路を構成する配管等の汚れや腐食を進行させるおそれがある。そのため、エンジンの運転中にＥＧＲブロワを停止するときは、ＥＧＲ流路に掃気を流入させて排ガスを排出するのが望ましいことが判明した。ただし、ＥＧＲ流路に流入させる掃気の量が多すぎると、エンジンへ供給する掃気の供給量が不足し、燃費の悪化、さらには失火するという問題もある。   However, if the exhaust gas remains in the EGR passage, there is a possibility that the piping or the like forming the EGR passage may be contaminated or corroded. Therefore, when stopping the EGR blower while the engine is operating, it has been found that it is desirable to allow scavenging air to flow into the EGR passage to discharge the exhaust gas. However, if the amount of scavenging gas flowing into the EGR flow path is too large, there is a problem that the amount of scavenging gas supplied to the engine is insufficient, resulting in deterioration of fuel efficiency and further misfire.

以上のような事情に鑑みて、本発明では、エンジンの運転中にＥＧＲブロワを停止したとき、ＥＧＲ流路に微小量の掃気を流入させることができるＥＧＲユニットを提供することを目的とする。また、エンジンの運転中にＥＧＲブロワを停止したとき、ＥＧＲ流路に微小量の掃気を流入させることができるエンジンシステムを提供することを目的とする。   In view of the circumstances as described above, it is an object of the present invention to provide an EGR unit that can allow a small amount of scavenging air to flow into the EGR flow path when the EGR blower is stopped while the engine is operating. Another object of the present invention is to provide an engine system that can allow a small amount of scavenging air to flow into the EGR passage when the EGR blower is stopped while the engine is operating.

本発明の一態様に係るＥＧＲユニットは、舶用２サイクルエンジンを備えたエンジンシステムに設けられており、排ガス流路から排ガスを抽出し、抽出した排ガスを前記排ガス流路よりも圧力の高い掃気流路へ供給するＥＧＲユニットであって、前記排ガス流路と前記掃気流路とをつなぐＥＧＲ流路と、前記ＥＧＲ流路に設けられたＥＧＲブロワと、を備え、前記ＥＧＲ流路は、前記ＥＧＲブロワが停止したとき、前記排ガス流路と前記掃気流路の圧力差を利用して、前記ＥＧＲ流路の出口から掃気を流入させ、流入した掃気によって当該ＥＧＲ流路内の排ガスを前記排ガス流路へ排出するように構成されており、前記ＥＧＲブロワは、エンジンの運転中に当該ＥＧＲブロワが停止したとき、当該ＥＧＲブロワが有する複数の部材のうち相対移動する部材間の隙間を掃気が漏れ流れるように構成されている。   An EGR unit according to one aspect of the present invention is provided in an engine system including a two-cycle engine for a marine vessel, extracts exhaust gas from an exhaust gas passage, and extracts the exhaust gas having a higher pressure than the exhaust gas passage. An EGR unit for supplying the exhaust gas flow path and the scavenging flow path, and an EGR blower provided in the EGR flow path, the EGR flow path being configured to supply the exhaust gas flow path to the scavenging flow path. When the blower is stopped, the pressure difference between the exhaust gas flow passage and the scavenging flow passage is used to cause scavenging air to flow from the outlet of the EGR flow passage, and the exhaust gas in the EGR flow passage is caused to flow into the exhaust gas flow by the inflowing scavenging gas. The EGR blower is configured to discharge to a road, and when the EGR blower stops while the engine is operating, the scavenging air leaks through a gap between members that relatively move among a plurality of members included in the EGR blower. It is designed to flow.

このＥＧＲユニットでは、ＥＧＲブロワは、エンジンの運転中に当該ＥＧＲブロワが停止したとき、当該ＥＧＲブロワが有する複数の部材のうち相対移動する部材間の隙間を掃気が漏れ流れるように構成されている。つまり、ＥＧＲブロワが停止したとき、ＥＧＲブロワ自体がオリフィスとして機能するため、ＥＧＲブロワを停止したとき、エンジンへ供給する掃気の供給量が必要以上に低下するのを防ぎつつ、ＥＧＲ流路に微小量の掃気を流入させることができる。よって、上記の構成によれば、エンジンの運転中にＥＧＲブロワを停止したとき、ＥＧＲ流路に微小量の掃気を流入させることができるＥＧＲユニットを提供することができる。   In this EGR unit, the EGR blower is configured such that, when the EGR blower is stopped during the operation of the engine, the scavenging air leaks through a gap between the members that relatively move among the plurality of members included in the EGR blower. .. In other words, when the EGR blower stops, the EGR blower itself functions as an orifice. Therefore, when the EGR blower is stopped, the supply amount of scavenging air to be supplied to the engine is prevented from unnecessarily decreasing, and the EGR flow path has a small amount. A quantity of scavenging air can be admitted. Therefore, according to the above configuration, it is possible to provide an EGR unit capable of causing a minute amount of scavenging air to flow into the EGR flow path when the EGR blower is stopped while the engine is operating.

上記のＥＧＲユニットにおいて、前記ＥＧＲブロワは、複数の第１羽根を有する第１ロータと、複数の第２羽根を有する第２ロータと、前記第１ロータ及び前記第２ロータを収容するケーシングと、を有するルーツブロワであって、前記ＥＧＲブロワは、エンジンの運転中に当該ＥＧＲブロワが停止したとき、前記第１羽根と前記第２羽根の隙間、前記第１羽根と前記ケーシングの隙間、及び、前記第２羽根と前記ケーシングの隙間を掃気が漏れ流れるように構成されていてもよい。   In the above EGR unit, the EGR blower includes a first rotor having a plurality of first blades, a second rotor having a plurality of second blades, and a casing that houses the first rotor and the second rotor, Wherein the EGR blower has a gap between the first blade and the second blade, a gap between the first blade and the casing, and the EGR blower when the EGR blower stops during engine operation. The scavenging air may leak through the gap between the second blade and the casing.

容積式であるルーツブロワは、軸流式のブロワ等に比べて部材間の隙間が小さい。そのため、上記の構成によれば、相対移動する部材間の隙間を掃気が漏れ流れるＥＧＲブロワを実現することができる。   The volume type roots blower has a smaller gap between members than an axial flow type blower. Therefore, according to the above configuration, it is possible to realize an EGR blower in which scavenging air leaks and flows through a gap between members that relatively move.

上記のＥＧＲユニットにおいて、前記第１羽根と前記第２羽根の隙間、前記第１羽根と前記ケーシングの隙間、及び、前記第２羽根と前記ケーシングの隙間は、いずれも０.１ｍｍ以上１.５ｍｍ以下であってもよい。   In the above EGR unit, the gap between the first blade and the second blade, the gap between the first blade and the casing, and the gap between the second blade and the casing are all 0.1 mm or more and 1.5 mm. It may be the following.

この構成によれば、エンジンの運転中にＥＧＲブロワを停止したとき、ＥＧＲ流路に適切な量の掃気を流入させることができる。   According to this configuration, when the EGR blower is stopped while the engine is operating, an appropriate amount of scavenging air can flow into the EGR passage.

上記のＥＧＲユニットにおいて、前記ＥＧＲ流路の前記ＥＧＲブロワよりも排ガス流路側に設けられ、エンジンの運転中に前記ＥＧＲブロワが停止したときに閉じられる入口弁をさらに備え、前記入口弁は、前記ＥＧＲブロワが停止して当該入口弁が閉じたとき、前記入口弁が有する弁体と弁座の隙間を掃気が漏れ流れるように構成されていてもよい。   In the above EGR unit, further provided is an inlet valve which is provided on the exhaust gas passage side of the EGR passage with respect to the EGR blower, and which is closed when the EGR blower is stopped during engine operation. When the EGR blower is stopped and the inlet valve is closed, the scavenging air may flow through the gap between the valve body and the valve seat of the inlet valve.

この構成によれば、入口弁が閉じたとき、入口弁がオリフィスとして機能するため、ＥＧＲ流路に流入する掃気の量をより一層抑えることができる。その結果、エンジンに供給される掃気の供給量が増えて、エンジンの燃費を向上させることができる。   According to this configuration, when the inlet valve is closed, the inlet valve functions as an orifice, so that the amount of scavenging gas flowing into the EGR passage can be further suppressed. As a result, the amount of scavenging air supplied to the engine is increased, and the fuel efficiency of the engine can be improved.

また、本発明の一態様に係るエンジンシステムは、上記のＥＧＲユニットのうちのいずれかを備えている。   An engine system according to one aspect of the present invention includes any of the above EGR units.

この構成によれば、エンジンの運転中にＥＧＲブロワを停止したとき、ＥＧＲ流路に微小量の掃気を流入させることができるエンジンシステムを提供することができる。   According to this configuration, when the EGR blower is stopped during the operation of the engine, it is possible to provide an engine system that allows a small amount of scavenging air to flow into the EGR passage.

上記の構成によれば、エンジンの運転中にＥＧＲブロワを停止したとき、ＥＧＲ流路に微小量の掃気を流入させることができるＥＧＲユニットを提供することができる。また、エンジンの運転中にＥＧＲブロワを停止したとき、ＥＧＲ流路に微小量の掃気を流入させることができるエンジンシステムを提供することができる。   According to the above configuration, it is possible to provide an EGR unit that can allow a small amount of scavenging air to flow into the EGR flow path when the EGR blower is stopped while the engine is operating. Further, it is possible to provide an engine system capable of causing a minute amount of scavenging air to flow into the EGR passage when the EGR blower is stopped while the engine is operating.

図１は、エンジンシステムの全体図である。FIG. 1 is an overall view of an engine system.

＜エンジンシステム＞
以下、本発明の実施形態に係るエンジンシステム１００について説明する。はじめに、エンジンシステム１００の全体構造について説明する。図１は、エンジンシステム１００の全体図である。図１において、太く描いた破線は排ガスの流れを示しており、太く描いた実線は掃気の流れを示している。図１に示すように、本実施形態に係るエンジンシステム１００は大型船舶用のエンジンシステムであって、エンジン１０と、排ガス流路２０と、過給機３０と、掃気流路４０と、ＥＧＲユニット５０と、を備えている。 <Engine system>
Hereinafter, the engine system 100 according to the embodiment of the present invention will be described. First, the overall structure of the engine system 100 will be described. FIG. 1 is an overall view of the engine system 100. In FIG. 1, the thickly drawn broken line shows the flow of exhaust gas, and the thickly drawn solid line shows the flow of scavenging gas. As shown in FIG. 1, an engine system 100 according to the present embodiment is an engine system for a large ship, and includes an engine 10, an exhaust gas passage 20, a supercharger 30, a scavenging passage 40, and an EGR unit. And 50.

本実施形態のエンジン１０は、大型船舶の推進用主機であり、２サイクルディーゼルエンジンである。エンジン１０は、複数のシリンダ１１（図１では１つのシリンダ１１のみ図示している）を有しており、各シリンダ１１内で燃料が爆発燃焼することでピストン１２が駆動する。なお、エンジン１０は、２サイクルエンジンであればよく、２サイクルディーゼルエンジンの他、２サイクル二元燃料エンジン等であってもよい。   The engine 10 of this embodiment is a main engine for propulsion of a large ship, and is a two-cycle diesel engine. The engine 10 has a plurality of cylinders 11 (only one cylinder 11 is shown in FIG. 1), and the piston 12 is driven by explosive combustion of fuel in each cylinder 11. The engine 10 may be a two-cycle engine, and may be a two-cycle dual-fuel engine or the like in addition to the two-cycle diesel engine.

排ガス流路２０は、シリンダ１１内における燃料の爆発燃焼によって発生した排ガスを外部へ排出する流路である。排ガス流路２０は、図外の配管の他、エンジン１０の出口付近に位置する排気管２１等によって形成されている。つまり、排ガス流路２０は、排気管２１を有している。エンジン１０で発生した排ガスは、一時的に排気管２１に溜められた後、過給機３０に向かって排出される。   The exhaust gas passage 20 is a passage for discharging the exhaust gas generated by the explosive combustion of the fuel in the cylinder 11 to the outside. The exhaust gas passage 20 is formed by an exhaust pipe 21 and the like located near the outlet of the engine 10, in addition to piping not shown. That is, the exhaust gas passage 20 has the exhaust pipe 21. The exhaust gas generated by the engine 10 is temporarily stored in the exhaust pipe 21, and then discharged toward the supercharger 30.

過給機３０は、掃気を圧縮する装置である。過給機３０は、排ガス流路２０に設けられたタービン部３１と、掃気流路４０に設けられたコンプレッサ部３２と、タービン部３１とコンプレッサ部３２を連結する連結軸３３を有している。排ガスのエネルギによりタービン部３１が回転すると、これに伴ってコンプレッサ部３２も回転する。コンプレッサ部３２が回転することにより、外部から取り込んだ掃気（新気）が圧縮される。   The supercharger 30 is a device that compresses scavenging air. The supercharger 30 has a turbine section 31 provided in the exhaust gas flow path 20, a compressor section 32 provided in the scavenging flow path 40, and a connecting shaft 33 that connects the turbine section 31 and the compressor section 32. .. When the turbine section 31 rotates due to the energy of the exhaust gas, the compressor section 32 also rotates accordingly. As the compressor unit 32 rotates, the scavenging air (fresh air) taken in from the outside is compressed.

掃気流路４０は、エンジン１０に掃気を供給する流路である。過給機３０により圧縮された掃気は掃気流路４０を流れ、合流点４１において後述するＥＧＲ流路５１から供給された排ガスを取り込んだ後、エンジン１０へ供給される。掃気流路４０は、図外の配管の他、エンジン１０の入口付近に位置する掃気管４２等によって形成されている。つまり、掃気流路４０は、掃気管４２を有している。掃気管４２は掃気を一時的に溜めた後、エンジン１０へ供給する。   The scavenging flow passage 40 is a flow passage that supplies scavenging air to the engine 10. The scavenging air compressed by the supercharger 30 flows through the scavenging air passage 40, takes in the exhaust gas supplied from the EGR passage 51 described later at the confluence 41, and is then supplied to the engine 10. The scavenging flow passage 40 is formed by a scavenging pipe 42 and the like located near the inlet of the engine 10 in addition to piping not shown. That is, the scavenging flow passage 40 has the scavenging pipe 42. The scavenging pipe 42 temporarily stores the scavenging gas and then supplies it to the engine 10.

なお、上述した通り、本実施形態のエンジン１０は、２サイクルエンジンである。２サイクルエンジンは、ピストン１２が下死点近傍にあり掃気ポートが開いているとき、掃気がシリンダ１１内に流入してシリンダ１１内の排ガスを排出するように構成されている。そのため、掃気流路４０の圧力は、排ガス流路２０の圧力よりも常に高い。   Note that, as described above, the engine 10 of this embodiment is a two-cycle engine. The two-cycle engine is configured so that, when the piston 12 is near the bottom dead center and the scavenging port is open, the scavenging gas flows into the cylinder 11 and discharges the exhaust gas in the cylinder 11. Therefore, the pressure of the scavenging passage 40 is always higher than the pressure of the exhaust gas passage 20.

ＥＧＲユニット５０は、排ガス流路２０から排ガスを抽出して掃気流路４０に供給するユニットである。排ガスを掃気流路４０に供給することで、掃気の酸素濃度が下がり、シリンダ内での燃焼時間が長くなる結果、燃焼最高温度が低下し、掃気中の窒素と結合するサーマルＮＯｘの発生を抑え、結果として排ガスに含まれるＮＯｘの排出量を抑制することができる。ＥＧＲユニット５０の詳細については後述する。   The EGR unit 50 is a unit that extracts the exhaust gas from the exhaust gas passage 20 and supplies it to the scavenging passage 40. By supplying the exhaust gas to the scavenging flow passage 40, the oxygen concentration of the scavenging gas is lowered and the combustion time in the cylinder is lengthened. As a result, the maximum combustion temperature is lowered, and the generation of thermal NOx combined with nitrogen in the scavenging gas is suppressed. As a result, the amount of NOx contained in the exhaust gas can be suppressed. Details of the EGR unit 50 will be described later.

＜ＥＧＲユニット＞
次に、ＥＧＲユニット５０について詳しく説明する。図１に示すように、本実施形態のＥＧＲユニット５０は、ＥＧＲ流路５１と、スクラバ５２と、ＥＧＲブロワ５３と、入口弁５４と、を有している。 <EGR unit>
Next, the EGR unit 50 will be described in detail. As shown in FIG. 1, the EGR unit 50 of the present embodiment has an EGR passage 51, a scrubber 52, an EGR blower 53, and an inlet valve 54.

ＥＧＲ流路５１は、排ガス流路２０から排ガスを抽出し、抽出した排ガスを掃気流路４０へ供給する流路である。本実施形態のＥＧＲ流路５１は、図外の配管等により形成されており、排ガス流路２０の排気管２１と掃気流路４０の掃気管４２よりも上流側の部分とをつないでいる。ただし、ＥＧＲ流路５１は、排ガス流路２０と掃気流路４０をつないでいればよく、接続箇所は限定されない。例えば、ＥＧＲ流路５１は、排気管２１と掃気管４１をつないでいてもよい。   The EGR flow path 51 is a flow path that extracts the exhaust gas from the exhaust gas flow path 20 and supplies the extracted exhaust gas to the scavenging flow path 40. The EGR flow path 51 of the present embodiment is formed by a pipe or the like (not shown), and connects the exhaust pipe 21 of the exhaust gas flow path 20 and the upstream side of the scavenging pipe 42 of the scavenging flow path 40. However, the EGR passage 51 is not limited as long as it connects the exhaust gas passage 20 and the scavenging passage 40. For example, the EGR flow path 51 may connect the exhaust pipe 21 and the scavenging pipe 41.

スクラバ５２は、ＥＧＲ流路５１に取り込んだ排ガスを洗浄する装置である。本実施形態のエンジン１０は重油を燃料としており、排ガスにはＳＯｘ及び多量のすす等が含まれる。ＥＧＲ流路５１に取り込んだ排ガスをそのままエンジン１０に供給すると、排ガスに含まれるＳＯｘ及びすす等がエンジン１０に悪影響を及ぼす。そこで、本実施形態ではスクラバ５２を用いて排ガスからＳＯｘ及びすす等を取り除いている。   The scrubber 52 is a device for cleaning the exhaust gas taken into the EGR passage 51. The engine 10 of the present embodiment uses heavy oil as fuel, and the exhaust gas contains SOx and a large amount of soot. When the exhaust gas taken into the EGR passage 51 is supplied to the engine 10 as it is, SOx and soot contained in the exhaust gas adversely affect the engine 10. Therefore, in the present embodiment, the scrubber 52 is used to remove SOx and soot from the exhaust gas.

ＥＧＲブロワ５３は、ＥＧＲ流路５１のスクラバ５２よりも下流に設けられ、排ガスを掃気流路４０へ圧送する装置である。本実施形態のＥＧＲブロワ５３は、回転数と送風量が比例する容積式のブロワであり、より具体的にはルーツブロワである。図１に示すように、ＥＧＲブロワ５３は、第１ロータ６１と、第２ロータ６２と、第１ロータ６１及び第２ロータ６２を収容するケーシング６３と、を有している。   The EGR blower 53 is a device that is provided downstream of the scrubber 52 in the EGR flow path 51 and sends exhaust gas under pressure to the scavenging flow path 40. The EGR blower 53 of the present embodiment is a positive displacement blower in which the number of revolutions and the amount of blown air are proportional, and more specifically, a roots blower. As shown in FIG. 1, the EGR blower 53 has a first rotor 61, a second rotor 62, and a casing 63 that houses the first rotor 61 and the second rotor 62.

本実施形態のＥＧＲブロワ５３は、３葉式のルーツブロワであるため、第１ロータ６１は３つの第１羽根６５を有しており、第２ロータ６２は３つの第２羽根６６を有している。ＥＧＲブロワ５３が２葉式のルーツブロワであれば、第１ロータ６１は２つの第１羽根６５を有し、第２ロータ６２は２つの第２羽根６６を有することになる。ＥＧＲブロワ５３が駆動している間は、第１ロータ６１と第２ロータ６２は、ケーシング６３内で互いに噛み合うようにして回転する。そのため、第１羽根６５と第２羽根６６は相対移動し、第１羽根６５とケーシング６３は相対移動し、第２羽根６６とケーシング６３は相対移動する。   Since the EGR blower 53 of this embodiment is a three-leaf roots blower, the first rotor 61 has three first blades 65, and the second rotor 62 has three second blades 66. There is. If the EGR blower 53 is a two-leaf roots blower, the first rotor 61 has two first blades 65 and the second rotor 62 has two second blades 66. While the EGR blower 53 is driven, the first rotor 61 and the second rotor 62 rotate so as to mesh with each other inside the casing 63. Therefore, the first blade 65 and the second blade 66 relatively move, the first blade 65 and the casing 63 relatively move, and the second blade 66 and the casing 63 relatively move.

上述のとおり、ルーツブロワは容積式のブロワであるため、第１羽根６５と第２羽根６６との間、第１羽根６５とケーシング６３との間、及び、第２羽根６６とケーシング６３との間からは圧送する流体が極力漏れないことが望ましい。しかしながら、これらの部材の間に隙間がなければ第１ロータ６１及び第２ロータ６２は回転できない。そのため、実際にはこれらの部材の間にはわずかな隙間が形成されている。本実施形態では、これらの隙間はいずれも０.１ｍｍ以上１.５ｍｍ以下に設定されている。   As described above, since the roots blower is a positive displacement blower, it is between the first blade 65 and the second blade 66, between the first blade 65 and the casing 63, and between the second blade 66 and the casing 63. Therefore, it is desirable that the fluid to be pumped does not leak as much as possible. However, if there is no gap between these members, the first rotor 61 and the second rotor 62 cannot rotate. Therefore, a slight gap is actually formed between these members. In this embodiment, all of these gaps are set to 0.1 mm or more and 1.5 mm or less.

入口弁５４は、ＥＧＲ流路５１の入口側に設けられた弁である。本実施形態では、ＥＧＲ流路５１のスクラバ５２より上流側に設けられている。また、入口弁５４は、ＥＧＲブロワ５３が停止したときに閉じるように構成されている。なお、本実施形態の入口弁５４はバタフライ弁であるが、入口弁５４はバタフライ弁の他、ゲート弁など他のバルブであってもよい。   The inlet valve 54 is a valve provided on the inlet side of the EGR flow path 51. In this embodiment, the EGR passage 51 is provided on the upstream side of the scrubber 52. Further, the inlet valve 54 is configured to close when the EGR blower 53 stops. Although the inlet valve 54 of this embodiment is a butterfly valve, the inlet valve 54 may be a butterfly valve or another valve such as a gate valve.

入口弁５４は、高温の排ガスを閉止または通過させることができるように金属で形成された弁体７１と、同じく金属で形成された弁座７２を有している。そして、入口弁５４が閉じたときには、弁体７１と弁座７２はシール部材等を介さずに直接接触する。つまり、本実施形態の入口弁５４は、メタルタッチ構造が採用されている。そのため、入口弁５４が閉じた状態であっても、弁体７１と弁座７２との間にわずかな隙間が形成されている。   The inlet valve 54 has a valve body 71 made of metal so as to close or allow passage of high-temperature exhaust gas, and a valve seat 72 also made of metal. When the inlet valve 54 is closed, the valve body 71 and the valve seat 72 are in direct contact with each other without a seal member or the like. That is, the inlet valve 54 of this embodiment has a metal touch structure. Therefore, even when the inlet valve 54 is closed, a slight gap is formed between the valve body 71 and the valve seat 72.

以上のとおり、本実施形態のＥＧＲユニット５０には、エンジン１０の運転中にＥＧＲブロワ５３が停止したとき、ＥＧＲ流路５１内の流体を完全に止めるような弁又は部材は設けられていない。ＥＧＲブロワ５３は部材間にわずかな隙間が存在し、入口弁５４は閉じたときに弁体７１と弁座７２の間にはわずかな隙間が存在する。   As described above, the EGR unit 50 of the present embodiment is not provided with a valve or member that completely stops the fluid in the EGR flow path 51 when the EGR blower 53 stops during the operation of the engine 10. The EGR blower 53 has a slight gap between members, and the inlet valve 54 has a slight gap between the valve body 71 and the valve seat 72 when closed.

＜ＥＧＲユニットの動作＞
次に、ＥＧＲユニット５０の動作について説明する。エンジンシステム１００が駆動している間は常にＥＧＲが実施されているわけではなく、エンジンシステム１００が搭載されている船舶の航行海域やエンジンシステム１００の運転状況に応じてＥＧＲを停止する。エンジン１０の運転中にＥＧＲブロワ５３を停止することにより、排ガスが掃気流路４０に供給されなくなり、ＥＧＲが停止される。また、ＥＧＲブロワ５３の停止に伴って、入口弁５４は閉じられる。 <Operation of EGR unit>
Next, the operation of the EGR unit 50 will be described. While the engine system 100 is driven, the EGR is not always performed, and the EGR is stopped according to the navigation area of the ship in which the engine system 100 is mounted and the operating condition of the engine system 100. By stopping the EGR blower 53 during the operation of the engine 10, the exhaust gas is not supplied to the scavenging flow passage 40, and the EGR is stopped. Further, the inlet valve 54 is closed as the EGR blower 53 is stopped.

前述したとおり、掃気流路４０の圧力は、排ガス流路２０の圧力よりも高い。そして、本実施形態のＥＧＲユニット５０には、エンジン１０の運転中にＥＧＲブロワ５３が停止したとき、ＥＧＲ流路５１内の流体を完全に止めるような弁又は部材は設けられていない。そのため、ＥＧＲブロワ５３が停止したときには、排ガス流路２０と掃気流路４０の圧力差によって、ＥＧＲ流路５１の出口から掃気が流入する。これにより、ＥＧＲ流路５１に残った排ガスは流入した排ガスによって排ガス流路２０へ排出される。その結果、ＥＧＲ流路５１に残った排ガスによって、ＥＧＲ流路５１を構成する配管等の汚れや腐食が進行するのを抑制することができる。   As described above, the pressure in the scavenging passage 40 is higher than the pressure in the exhaust gas passage 20. Further, the EGR unit 50 of the present embodiment is not provided with a valve or member that completely stops the fluid in the EGR flow path 51 when the EGR blower 53 stops during the operation of the engine 10. Therefore, when the EGR blower 53 is stopped, the scavenging air flows from the outlet of the EGR passage 51 due to the pressure difference between the exhaust gas passage 20 and the scavenging passage 40. As a result, the exhaust gas remaining in the EGR flow channel 51 is discharged to the exhaust gas flow channel 20 by the inflowing exhaust gas. As a result, it is possible to suppress the progress of dirt and corrosion of the pipes and the like that form the EGR passage 51 due to the exhaust gas remaining in the EGR passage 51.

さらに、ＥＧＲブロワ５３を形成する部材間には隙間が存在し、入口弁５４の弁体７１と弁座７２の間には隙間が存在するものの、それらの隙間はわずかな隙間である。そのため、エンジン１０の運転中にＥＧＲブロワ５３が停止したとき、ＥＧＲブロワ５３及び入口弁５４はそれぞれオリフィスとして機能する。これにより、ＥＧＲ流路５１に流入する掃気の量は微小量となり、掃気の減少によるエンジン１０の燃費の悪化を抑制することができる。   Further, although a gap exists between the members forming the EGR blower 53 and a gap exists between the valve body 71 and the valve seat 72 of the inlet valve 54, those gaps are slight gaps. Therefore, when the EGR blower 53 stops during the operation of the engine 10, the EGR blower 53 and the inlet valve 54 each function as an orifice. As a result, the amount of scavenging air that flows into the EGR flow path 51 becomes a minute amount, and it is possible to suppress deterioration of fuel efficiency of the engine 10 due to a decrease in scavenging air.

１０ エンジン
２０ 排ガス流路
４０ 掃気流路
５０ ＥＧＲユニット
５１ ＥＧＲ流路
５３ ＥＧＲブロワ
５４ 入口弁
６１ 第１ロータ
６２ 第２ロータ
６３ ケーシング
６５ 第１羽根
６６ 第２羽根
７１ 弁体
７２ 弁座
１００ エンジンシステム 10 engine 20 exhaust gas flow path 40 scavenging flow path 50 EGR unit 51 EGR flow path 53 EGR blower 54 inlet valve 61 first rotor 62 second rotor 63 casing 65 first blade 66 second blade 71 valve body 72 valve seat 100 engine system

Claims (5)

舶用２サイクルエンジンを備えたエンジンシステムに設けられており、排ガス流路から排ガスを抽出し、抽出した排ガスを前記排ガス流路よりも圧力の高い掃気流路へ供給するＥＧＲユニットであって、
前記排ガス流路と前記掃気流路とをつなぐＥＧＲ流路と、
前記ＥＧＲ流路に設けられたＥＧＲブロワと、を備え、
前記ＥＧＲ流路は、前記ＥＧＲブロワが停止したとき、前記排ガス流路と前記掃気流路の圧力差を利用して、前記ＥＧＲ流路の出口から掃気を流入させ、流入した掃気によって当該ＥＧＲ流路内の排ガスを前記排ガス流路へ排出するように構成されており、
前記ＥＧＲブロワは、エンジンの運転中に当該ＥＧＲブロワが停止したとき、当該ＥＧＲブロワが有する複数の部材のうち相対移動する部材間の隙間を掃気が漏れ流れるように構成されている、ＥＧＲユニット。 An EGR unit provided in an engine system equipped with a two-cycle marine engine, which extracts exhaust gas from an exhaust gas passage and supplies the extracted exhaust gas to a scavenging passage having a higher pressure than the exhaust passage.
An EGR channel connecting the exhaust gas channel and the scavenging channel,
An EGR blower provided in the EGR flow path,
When the EGR blower is stopped, the EGR flow path uses the pressure difference between the exhaust gas flow path and the scavenging flow path to allow scavenging air to flow in from the outlet of the EGR flow path, and the EGR flow is caused by the inflowing scavenging gas. The exhaust gas in the passage is configured to be discharged to the exhaust gas passage,
The EGR blower is an EGR unit configured such that, when the EGR blower is stopped while the engine is operating, scavenging air leaks and flows through a gap between members that relatively move among a plurality of members included in the EGR blower. 前記ＥＧＲブロワは、
複数の第１羽根を有する第１ロータと、
複数の第２羽根を有する第２ロータと、
前記第１ロータ及び 前記第２ロータを収容するケーシングと、
を有するルーツブロワであって、
前記ＥＧＲブロワは、エンジンの運転中に当該ＥＧＲブロワが停止したとき、前記第１羽根と前記第２羽根の隙間、前記第１羽根と前記ケーシングの隙間、及び、前記第２羽根と前記ケーシングの隙間を掃気が漏れ流れるように構成されている、請求項１に記載のＥＧＲユニット。 The EGR blower is
A first rotor having a plurality of first blades;
A second rotor having a plurality of second blades;
A casing accommodating the first rotor and the second rotor;
A roots blower having
The EGR blower has a gap between the first blade and the second blade, a gap between the first blade and the casing, and a gap between the second blade and the casing when the EGR blower is stopped during operation of the engine. The EGR unit according to claim 1, wherein the scavenging air leaks through the gap. 前記第１羽根と前記第２羽根の隙間、前記第１羽根と前記ケーシングの隙間、及び、前記第２羽根と前記ケーシングの隙間は、いずれも０.１ｍｍ以上１.５ｍｍ以下である、請求項２に記載のＥＧＲユニット。   The clearance between the first blade and the second blade, the clearance between the first blade and the casing, and the clearance between the second blade and the casing are each 0.1 mm or more and 1.5 mm or less. The EGR unit described in 2. 前記ＥＧＲ流路の前記ＥＧＲブロワよりも排ガス流路側に設けられ、エンジンの運転中に前記ＥＧＲブロワが停止したときに閉じられる入口弁をさらに備え、
前記入口弁は、エンジンの運転中に前記ＥＧＲブロワが停止して当該入口弁が閉じたとき、前記入口弁が有する弁体と弁座の隙間を掃気が漏れ流れるように構成されている、請求項１乃至３のうちいずれか一の項に記載のＥＧＲユニット。 An inlet valve that is provided on the exhaust gas flow passage side of the EGR flow passage in the EGR flow passage and that is closed when the EGR blower stops during engine operation;
The inlet valve is configured such that when the EGR blower is stopped and the inlet valve is closed during engine operation, scavenging gas leaks and flows through a gap between the valve body and the valve seat of the inlet valve. The EGR unit according to any one of the items 1 to 3. 請求項１乃至４のうちいずれか一の項に記載のＥＧＲユニットを備えたエンジンシステム。   An engine system comprising the EGR unit according to any one of claims 1 to 4.
JP2018211689A 2018-11-09 2018-11-09 EGR unit and engine system Active JP6550520B1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
JP2018211689A JP6550520B1 (en) 2018-11-09 2018-11-09 EGR unit and engine system
KR1020190132953A KR102162893B1 (en) 2018-11-09 2019-10-24 Egr unit and engine system
CN201911077444.4A CN111173654B (en) 2018-11-09 2019-11-06 EGR unit and engine system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2018211689A JP6550520B1 (en) 2018-11-09 2018-11-09 EGR unit and engine system

Publications (2)

Publication Number Publication Date
JP6550520B1 JP6550520B1 (en) 2019-07-24
JP2020076392A true JP2020076392A (en) 2020-05-21

Family

ID=67390336

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2018211689A Active JP6550520B1 (en) 2018-11-09 2018-11-09 EGR unit and engine system

Country Status (3)

Country Link
JP (1) JP6550520B1 (en)
KR (1) KR102162893B1 (en)
CN (1) CN111173654B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115478945B (en) * 2022-08-16 2023-12-15 潍柴动力股份有限公司 Control method and device of exhaust gas recirculation system, electronic equipment and storage medium

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01203646A (en) * 1988-02-05 1989-08-16 Nippon Denso Co Ltd Egr control valve
JP2001003817A (en) * 1999-06-16 2001-01-09 Komatsu Ltd Exhaust circulating device and its control method
JP2011157959A (en) * 2010-01-29 2011-08-18 Man Diesel & Turbo Filial Af Man Diesel & Turbo Se Tyskland Large two-cycle diesel engine with exhaust gas recirculation system
WO2012026075A1 (en) * 2010-08-23 2012-03-01 株式会社コスメック Directional control valve device
JP2012198004A (en) * 2011-03-23 2012-10-18 Mitsutoshi Takebe Hot air generating apparatus
JP2014122575A (en) * 2012-12-20 2014-07-03 Kawasaki Heavy Ind Ltd EGR device and engine system
JP2016089689A (en) * 2014-11-04 2016-05-23 日野自動車株式会社 Egr device

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20140122575A (en) 2013-04-10 2014-10-20 정두보 Magnetic block toy
KR20150099926A (en) * 2014-02-24 2015-09-02 카와사키 주코교 카부시키 카이샤 EGR Device and Engine System
JP6633944B2 (en) * 2016-03-07 2020-01-22 川崎重工業株式会社 Engine system and control method

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01203646A (en) * 1988-02-05 1989-08-16 Nippon Denso Co Ltd Egr control valve
JP2001003817A (en) * 1999-06-16 2001-01-09 Komatsu Ltd Exhaust circulating device and its control method
JP2011157959A (en) * 2010-01-29 2011-08-18 Man Diesel & Turbo Filial Af Man Diesel & Turbo Se Tyskland Large two-cycle diesel engine with exhaust gas recirculation system
WO2012026075A1 (en) * 2010-08-23 2012-03-01 株式会社コスメック Directional control valve device
JP2012198004A (en) * 2011-03-23 2012-10-18 Mitsutoshi Takebe Hot air generating apparatus
JP2014122575A (en) * 2012-12-20 2014-07-03 Kawasaki Heavy Ind Ltd EGR device and engine system
JP2016089689A (en) * 2014-11-04 2016-05-23 日野自動車株式会社 Egr device

Also Published As

Publication number Publication date
CN111173654B (en) 2022-03-18
CN111173654A (en) 2020-05-19
KR20200054071A (en) 2020-05-19
JP6550520B1 (en) 2019-07-24
KR102162893B1 (en) 2020-10-07

Similar Documents

Publication Publication Date Title
JP4950082B2 (en) Marine diesel engine
RU2483220C2 (en) Method of operating large-size two-stroke diesel engine with cylinder longitudinal blow-out and large-size two-stroke diesel engine with cylinder longitudinal blow-out
KR101803445B1 (en) Marine exhaust gas purification device and ship engine system
JP2013002355A (en) Denitration device
KR20120088590A (en) Large turbocharged two-stroke diesel engine with exhaust gas recirculation
JP2012127205A (en) Exhaust gas recirculation system
BR112020018587A2 (en) SHIP PROPULSION SYSTEM AND RETROFIT METHOD FOR A SHIP PROPULSION SYSTEM
JP2020076392A (en) EGR unit and engine system
DK180131B1 (en) A large two-stroke uniflow scavenged gaseous fueled engine and method for reducing preignition/diesel-knock
JP2013238246A (en) Operating method for two-stroke and large-sized diesel engine scavenging air in longitudinal direction, and large-sized diesel engine scavenging air in longitudinal direction
JPH11247665A (en) Nitrogen oxides reducing structure of two cycle diesel engine
JP2011047393A (en) Marine diesel engine
JP5804756B2 (en) Supercharger system, internal combustion engine, and supercharger system control method
JP2011149329A (en) Marine internal combustion engine
JP6789793B2 (en) Internal combustion engine
JP6841645B2 (en) EGR system and diesel engine
JP2019039324A (en) Diesel engine for vessel
JP2007162530A (en) Exhaust emission control system for internal combustion engine
KR20130044803A (en) Engine performance enhancement at part load
CN204253220U (en) A kind of boats and ships two stroke diesel engine gas recirculation system
KR102663786B1 (en) Ship having air lubrication system using engine scavenge air
KR20200055517A (en) Ship having air lubrication system using engine scavenge air
KR20150099926A (en) EGR Device and Engine System
JP2012233471A (en) Internal combustion engine, and exhaust gas recirculation method for internal combustion engine
KR20170124335A (en) Pure oxygen gas engine

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20181109

A871 Explanation of circumstances concerning accelerated examination

Free format text: JAPANESE INTERMEDIATE CODE: A871

Effective date: 20181109

A975 Report on accelerated examination

Free format text: JAPANESE INTERMEDIATE CODE: A971005

Effective date: 20181121

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20181218

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20190305

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20190604

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20190701

R150 Certificate of patent or registration of utility model

Ref document number: 6550520

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250