KR20220070137A - Ship applied with air lubircation system and supply method for compressed air thereof - Google Patents

Abstract

The present invention relates to a ship to which an air lubrication system is applied, and which stores liquefied gas cargo inside a plurality of cargo tanks disposed in the longitudinal direction of a hull, and produces air bubbles on the surface of the bottom area of the hull to reduce frictional resistance of the hull. To this end, the ship of the present invention may comprise: a compressed air spray line which connects an ALS compression unit installed at the inner space of the bow of the hull to a plurality of nozzles formed on the surface of the bottom area of the hull, in order to spray compressed air to the surface of the bottom area of the hull; an ALS air chamber which is installed on the compressed air spray line to store compressed air; a nitrogen booster unit which is installed in an electric motor room disposed at the upper portion of a cargo tank of the stern among the plurality of cargo tanks, and generates nitrogen gas pressurized for a leakage test of various pipes disposed at the hull; and a second compressed air supply line which connects the nitrogen booster unit to the ALS air chamber to supply the compressed air generated in the nitrogen booster unit to the ALS air chamber for supplying the same. Therefore, electricity consumption may be minimized.

Description

A vessel to which an air lubrication system is applied and a method for supplying compressed air to the vessel

The present invention relates to an air lubrication system for a ship, and more particularly, to a ship to which an air lubrication system capable of reducing the frictional resistance of a ship by forming air bubbles on the surface of the bottom of a ship's hull, and compressed air supply of the ship it's about how

In general, frictional resistance acts between the hull and seawater during the operation of a ship, and the larger the ship, the greater the area in contact with the seawater, so the propulsion force may be greatly reduced, resulting in an increase in fuel cost. do.

Therefore, various efforts are being made to reduce the fuel cost required for the operation of a ship. By spraying compressed air on the surface of the bottom of the ship, air bubbles are spread between the hull and seawater like a carpet. It is known that reducing the frictional resistance of a ship is very effective.

As described above, a system for reducing the frictional resistance of a hull by forming an air layer through air bubbles on the surface of the ship's bottom is called an air lubrication system (ALS).

Figure 1 is a view schematically showing an air lubrication system of a ship according to the prior art, Figure 2 is a view showing the stern of the ship in the prior art.

Referring to FIG. 1 , in the prior art, a separate compression part 11 for an air lubrication system is installed on the bow side of a ship, and the compression part 11 is a plurality of It is connected to a nozzle (not shown) and is provided to spray compressed air on the surface of the ship bottom.

The air lubrication system of a ship according to the prior art sprays compressed air on the lower surface of the bow of the ship and the air bubbles spread to the stern side along the flow of seawater according to the operation of the ship, thereby reducing the frictional resistance of the hull and the propulsion of the ship may have the effect of improving

However, in the air lubrication system of a ship according to the prior art, the compression unit 11 additionally installed in the inner space of the bow side of the hull in order to supply compressed air to the surface of the bottom of the hull, specifically, compressed air of about 5,500 ㎥ per hour Only two compressors consuming 420 kW of power were used to generate a It can be inefficient in terms of savings.

On the other hand, a ship such as a liquefied natural gas carrier (LNGC; LNG Carrier) or an LNG RV (Regasification Vessel) is provided with a seawater cooling system for cooling various equipment installed in the hull, as shown in FIG. As shown, a seawater pump 24 is installed on the cooling line 23 connecting the sea chest 21 and the cooler 22 provided on the stern side, and the cooler ( The seawater is supplied to 22), and the cooler 22 cools the fresh water by using the seawater as a refrigerant to supply the cooled fresh water to various equipment requiring cooling.

However, when the air lubrication system is applied to such a vessel, air bubbles may be introduced into the sea chest 21 provided on the stern side of the hull, and the cavitation effect due to the air bubbles serves as the backbone of the vessel. It may adversely affect the cooling system, which is one of the systems.

Specifically, when air bubbles are introduced into the seawater pump 24 together with seawater, the flow rate and pressure of the seawater pump 24 may drop, which may cause malfunction or damage of the seawater pump 24, thereby causing the cooler It may be difficult to provide a smooth seawater supply to (22).

To solve this, in the prior art, a separate discharge line 25 extending from the sea chest 21 provided on the stern side to the upper deck of the hull is installed to discharge the air inside the sea chest However, as for the discharge line 25, a large pipe should be applied, and the additional installation of the discharge line 25 is required due to the same problem even after the ship is built according to the fluctuation of air bubbles sprayed on the surface of the ship's bottom. Not only does it increase the quantity, but it is also uncertain in terms of its effectiveness, so improvement is required.

The above-described technical configuration is a background for helping understanding of the present invention, and does not mean a conventional technique widely known in the technical field to which the present invention pertains.

Republic of Korea Patent Publication No. 10-2015-0111429 "A device for reducing resistance of a ship" Republic of Korea Patent Publication No. 10-1679491 “Air lubrication system”

In such a vessel, in addition to the air lubrication system and cooling system described above, when a fire occurs inside the engine room (ER), foam is generated and supplied to the engine room, thereby blocking the oxygen supply to the engine room. (ER) A high expansion foam extinguishing system capable of suppressing, or preventing (Total fire fighting), various fires that may be generated inside may be further provided.

In the ship according to the prior art, seawater is supplied to the fire extinguishing system using a fire pump (not shown) installed in the forward side, specifically, in the forward side hull, in the pump room (FWD Pump room). A large-capacity fire pump is required to generate the foam of can always follow.

In addition, in order to connect the fire pump installed on the bow side and the fire extinguishing system disposed on the stern side, a pipe of about 300 to 400 m from the fire pump to the fire extinguishing system should be installed extending from the bow side to the stern side, which is installed in the approximate center of the hull. Due to the plurality of cargo tanks and cofferdams disposed on the bow and stern sides of each of the plurality of cargo tanks, many restrictions may occur in connecting the fire pump and the fire extinguishing system.

To solve this, in the prior art, as shown in FIG. 2, a separate seawater storage unit 31 for supplying seawater to the fire extinguishing system from the lower portion of the steering gear room (SG) provided on the stern side And the seawater supply pump 33 is installed, and accordingly, it can have the effect of reducing the amount of piping through optimization of the pump capacity and the seawater supply line 32 .

On the other hand, the draft in the loaded state (laden draft) is generally 11.5m, and the draft in the ballast condition in which the ballast water is poured after unloading the cargo (Ballast draft) ) is about 9.4 m, whereas in the prior art, the seawater supply pump 33 could only be lowered to about 11 m from the bottom of the ship due to the nature of the ship's hull structure. can

To elaborate, the fire-fighting equipment-related standards of ships or the fire-fighting system in the classification should supply seawater to the fire-extinguishing system for 1 minute, extinguish fires in the engine room for 10 minutes, and extinguish five consecutive fires. (Fire fighting) is required.

The present invention relates to a ship to which an air lubrication system capable of reducing the frictional resistance of a ship is applied by spraying compressed air to the surface of the ship's bottom, a ship to which an air lubrication system capable of minimizing power consumption is applied, and compressed air of the ship An object of the present invention is to provide a supply control method.

Furthermore, in ships to which an air lubrication system is applied, air that can satisfy the classification requirements by preventing failure or damage of the seawater cooling pump due to air bubbles and solving the problem of delay in the supply of seawater in the fire extinguishing system for fire suppression Another object of the present invention is to provide a ship to which a lubrication system is applied and a method for supplying compressed air to the ship.

According to one aspect of the present invention, liquefied gas cargo is stored in a cargo tank provided in plurality along the longitudinal direction of the hull, and an air bubble is formed on the surface of the bottom of the hull to reduce the frictional resistance of the hull. As a ship to which an air lubrication system is applied, the ALS compression unit installed in the inner space of the bow side of the hull is connected to a plurality of nozzles formed on the surface of the bottom of the hull, and compressed air is applied to the surface of the bottom of the hull. ) compressed air injection line for spraying; an ALS air chamber installed on the compressed air injection line to store compressed air; A nitrogen booster unit (N2 booster) that is installed inside the electric motor room provided on the upper part of the stern side cargo tank among the plurality of cargo tanks, and generates pressurized nitrogen gas for leak test of various pipes provided in the hull. unit); and a second compressed air supply line connecting the nitrogen booster unit and the ALS air chamber to supply the compressed air generated in the nitrogen booster unit to the ALS air chamber. can

It is provided in the cargo compressor room partitioned from the electric motor room, and may further include a gas valve train (GVT) connected to the nitrogen booster unit by a nitrogen supply line.

In addition, the second compressed air supply line may be branched from the nitrogen supply line and connected to the ALS air chamber.

In addition, it may further include a third control valve for controlling the compressed air supply to the ALS air chamber on the second compressed air supply line.

In addition, an eductor installed at the rear end of the ALS air chamber on the compressed air injection line to suck the air inside the bow side hull (Eductor); and a regulator installed at a front end of the eductor on the compressed air injection line to adjust the pressure of compressed air supplied to the eductor.

In addition, a bypass line installed on the compressed air injection line, branched from the front end of the regulator and installed to bypass the regulator; and an on/off valve respectively installed on the front end of the regulator and the bypass line on the compressed air injection line.

In addition, an auxiliary injection line branched from the compressed air injection line between the ALS air chamber and the ALS compression unit, bypassing the eductor, and rejoining the compressed air injection line; and a control valve installed between a point where the eductor and the auxiliary injection line join on the compressed air injection line.

In addition, the compressed air generating unit is installed inside the engine room provided on the stern side of the hull to generate compressed air for combustion of the engine; and a first compressed air supply line for supplying the compressed air generated by the compressed air generator to the ALS air chamber.

In addition, the first compressed air supply line may be connected to the second compressed air supply line in the bow-side region of the hull.

In addition, it may further include a non-return valve installed on the first compressed air supply line to prevent a reverse flow of the compressed air supplied from the compressed air generator to the ALS air chamber.

In addition, the compressed air generator may include: a first compressor installed in the engine room and used to control compressed air supply to the engine while the engine is driven; and a first compressed air reservoir connected to the first compressor by a first storage line to store compressed air generated by the first compressor.

In addition, the first compressed air supply line may be branched from the first storage line and connected to the ALS air chamber.

In addition, the compressed air generator may include: a second compressor provided separately from the first compressor in the engine room and used when the engine is initially driven; a second compressed air reservoir connected to the second compressor by a second storage line to store compressed air generated by the second compressor; and an auxiliary supply line branched from the second storage line and connected to the first compressed air supply line.

In addition, the compressed air generating unit is installed adjacent to the first compressor on the compressed air supply line to supply the compressed air generated by the first compressor only to the first compressed air reservoir or the first compressed air reservoir a first control valve controlled to be supplied to the ALS air chamber together with; and a second installed on the auxiliary supply line and controlled to supply the compressed air generated by the second compressor only to the second compressed air reservoir or to the ALS air chamber together with the second compressed air reservoir It may further include a control valve.

In addition, it may further include a pressure measuring sensor for measuring the pressure inside the ALS air chamber.

In addition, the stern sea chest (Sea chest) provided on the stern side of the hull; a vent line (Vent line) for discharging the air bubbles introduced into the stern sea chest to the outside of the hull; and an ejector installed on the vent line and generating a negative pressure by using the compressed air generated from the compressed air generator.

In addition, the seawater storage unit provided under the steering gear room of the hull separately from the stern sea chest; a seawater supply pump installed on a seawater supply line connected to the seawater storage unit and mixing foam with the seawater stored in the seawater storage unit to extinguish a fire in a residence or the engine room; and a suction line branched from the seawater supply line between the seawater storage unit and the seawater supply pump and connected to the ejector to suck air in the seawater supply line.

In addition, it may further include a control unit for controlling the compressed air supply using the compressed air generating unit and the nitrogen booster unit.

According to another aspect of the present invention, there is provided a method for supplying compressed air to a ship to which an air lubrication system is applied, wherein at least one of the nitrogen booster unit and a compressed air generator for generating compressed air for combustion of an engine is used to produce the ALS air chamber. supplying compressed air to the furnace; and spraying the compressed air stored in the ALS air chamber to the surface of the bottom of the hull through the compressed air injection line.

In the step of spraying compressed air on the surface of the bottom of the hull, if all the compressed air stored in the ALS air chamber is used or insufficient, the ALS compression unit is operated and a separate auxiliary injection line bypassing the ALS air chamber is installed. Through this, the compressed air generated by the ALS compression unit may be supplied to the compressed air injection line.

In addition, in the step of spraying the compressed air on the surface of the bottom of the hull, when the pressure inside the ALS air chamber decreases, the compressed air stored in the ALS air chamber bypasses the regulator provided at the rear end of the ALS air chamber. It may include the step of supplying to the bottom surface of the hull.

In addition, in the step of supplying compressed air to the ALS air chamber, the compressed air generating unit discharges and removes air bubbles flowing into the stern sea chest provided on the stern side of the hull through a separate control unit to the outside of the hull. The mode and the mode for sucking air in the seawater supply line connecting the seawater storage unit provided under the steering gear room of the hull and the seawater supply pump may be controlled so that selective or simultaneous use is possible.

In addition, in the mode of removing the air bubble flowing into the stern sea chest by discharging it to the outside of the hull, the compression to provide negative pressure on the vent line through the ejector installed on the vent line of the stern sea chest Compressed air generated from the air generator may be used.

In addition, in the mode of sucking air in the seawater supply line, a negative pressure is applied to the front end of the seawater supply pump through a suction line branched from the seawater supply line between the seawater storage unit and the seawater supply pump and connected to the ejector. can provide

The present invention installs an ALS air chamber on a compressed air injection line and supplies compressed air to the ALS air chamber using idle equipment installed on the hull, thereby forming an air layer through air bubbles on the surface of the ship's bottom to form an air layer of the ship. It is possible to effectively reduce frictional resistance and also to minimize power consumption due to the operation of the air lubrication system.

Furthermore, in ships to which the air lubrication system is applied, it is possible to prevent failure or damage of the seawater cooling pump due to air bubbles, and to solve the problem of delay in supply of seawater in the fire extinguishing system for fire suppression, thereby satisfying the classification requirements.

1 is a view schematically showing a bow portion of a ship according to the prior art.
Figure 2 is a view schematically showing the stern portion of the ship according to the prior art.
3 is a diagram schematically illustrating a ship to which an air lubrication system according to an embodiment of the present invention is applied.
Figure 4 is an enlarged view of the bow of the ship shown in Figure 3;
5 is an enlarged view of the stern of FIG. 4 .
FIG. 6 is a view showing the area 'A' of FIG. 5 separated.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First of all, it should be noted that in adding reference numerals to the components of each drawing, the same components are given the same reference numerals as much as possible even though they are indicated on different drawings.

In describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

In addition, preferred embodiments of the present invention will be described below, but the technical spirit of the present invention is not limited thereto and may be variously implemented by those skilled in the art without being limited thereto.

Figure 3 is a view schematically showing a ship to which an air lubrication system according to an embodiment of the present invention is applied, Figure 4 is an enlarged view of the bow of the ship shown in Figure 3, Figure 5 is the stern of Figure 4 It is an enlarged view of the part, and FIG. 6 is a view showing area 'A' of FIG. 5 separately.

In describing the present invention with reference to FIG. 3, the side (left) on which the propulsion device (unsigned) is provided is the stern direction of the ship, and the opposite side (right) refers to the bow direction.

The ship of this embodiment, as shown in FIG. 3, is surrounded by a barrier (not shown) inside the hull and stores liquefied gas cargo such as LNG (Liquefied Natural Gas) inside the cargo tank (Cargo tank) (CT) and , may include an engine room (ER) in which an engine (not shown) is provided.

The cargo tank (CT) is provided with an insulating material for storing the liquefied gas cargo in a cryogenic state, and depending on whether the load of the insulating liquefied gas cargo directly acts on the membrane type or independent tank type (Independent) tank type) can be applied.

In this embodiment, a plurality of cargo tanks (CT) may be provided along the longitudinal direction of the hull, and a cofferdam (CD) may be disposed in a space between the plurality of cargo tanks (CT).

The cofferdam (CD) is a space forming an independent bulkhead between the plurality of cargo tanks (CT), and not only between the plurality of cargo tanks (CT), but also among the plurality of cargo tanks (CT) of the first cargo tank (CT). It can also be provided in the front (stern direction) and the rear (stern direction) of the stern cargo tank (CT).

In other words, the cofferdam (CD) may be provided on the bow side and the stern side of each of the plurality of cargo tanks (CT), and although not shown in the figure, the inside of the cofferdam (CD) includes a plurality of cargo tanks (CT) A plurality of gas supply lines for supplying an inert gas such as nitrogen to the inside of each barrier may be installed.

In the present embodiment, the engine provided in the engine room ER may be a MAN Electronic-Gas Injection engine (ME-GI engine) using gas of a high pressure of 300 bar or more as fuel oil.

In addition, the vessel of this embodiment may be additionally provided with a facility for processing the boil-off gas generated due to the vaporization of the liquefied gas cargo stored in the cargo tank CT or for supplying the liquefied gas cargo as a fuel of the engine.

Specifically, or a cargo compressor room (CCR) in which a boil-off gas compressor (not shown) for compressing boil-off gas is disposed on the upper portion of the stern-side cargo tank (CT) among the plurality of cargo tanks (CT) and evaporation An electric motor room (EMR) may be provided in which a motor (not shown) for driving the gas compressor is disposed.

Here, the cargo compressor room (CCR) and the electric motor room (EMR) are provided adjacent to each other in the upper part of the stern side cargo tank (CT), and are arranged in the cargo compressor room (CCR) classified as a hazardous zone There may be a risk of explosion due to sparks when the BOG compressor is driven.

In this embodiment, in order to protect the electric motor room (EMR) classified as a safety zone from the risk of explosion, the cargo compressor room (CCR) and the electric motor room (EMR) are partitioned into separate rooms. may be desirable.

Referring to FIG. 3 , the cargo compressor room (CCR) and the electric motor room (EMR) are shown to be provided on the stern side cargo tank (CT), but the present invention is not limited thereto, and the cargo compressor room (CCR) ) and the electric motor room (EMR) may be provided in the upper part of the engine room (ER) provided on the stern side.

On the other hand, in the ship having the above configuration, as described above, frictional resistance is applied by seawater to the hull submerged in water while the ship is operating, and the larger the ship, the greater the propulsion force due to an increase in the area in contact with the seawater. may be lowered, which may result in an increase in fuel costs.

The ship of this embodiment is equipped with an air lubrication system (ALS; Air Lubrication System) for reducing the frictional resistance of the hull by forming an air bubble (or more precisely, a micro air bubble) on the surface of the ship bottom of the hull (or , can be applied).

3 to 5 , the ship to which the air lubrication system according to an embodiment of the present invention is applied includes an ALS compression unit 110 installed in the internal space of the bow side of the hull and a plurality of formed on the bottom surface of the hull. It may include a compressed air injection line 120 connecting a nozzle (not shown), and an ALS air chamber 130 installed on the compressed air injection line 120 to store compressed air.

ALS compression unit 110 may be installed in the inner space of the bow side of the hull to generate compressed air.

In this embodiment, the ALS compression unit 110, unlike the prior art, is not continuously operated to spray compressed air on the surface of the ship bottom of the hull, but rather the ALS air chamber 130 to be described later. It can play a role of intermittent replenishment.

In addition, since the ship of this embodiment can store compressed air through the ALS air chamber 130, it is possible to supply a sufficient amount of compressed air to the surface of the bottom of the hull even if a compressor with a lower compressed air flow rate is used than in the prior art. may have an effect.

The ALS compression unit 110 in this embodiment is installed in the inner space of the bow side of the hull, has a compressed air flow rate of about 3,700 m 3 per hour, and may consist of three compressors consuming 160 kW of power.

The ALS air chamber 130 may be installed on the compressed air injection line 120 to receive compressed air from a compressed air generator 160 to be described later and store compressed air having a predetermined pressure (maximum 30 bar).

The ship to which the air lubrication system according to an embodiment of the present invention is applied has an air eductor 140 installed at the rear end of the ALS air chamber 130 on the compressed air injection line 120, and the ALS air chamber ( 130) and the eductor 140, that is, on the compressed air injection line 120, a regulator installed at the front end of the eductor 140 to control the pressure of compressed air supplied to the eductor 140 (Air regulator) (150) may be further included.

The eductor 140 can suck in the air inside the hull by using the compressed air of high pressure in the compressed air injection line 120, and use compressed air of a pressure (about 1 to 2 bar) suitable for the air lubrication system of the hull. It can be supplied on the bottom surface.

A ship to which the air lubrication system according to an embodiment of the present invention is applied is provided with an eductor 140 on the compressed air injection line 120 to spray compressed air on the surface of the bottom of the hull to the ALS air chamber 130 . Together with the stored compressed air, a greater volume of air can be provided to the bottom surface of the hull.

The regulator 150 may serve to regulate the pressure of the compressed air supplied from the ALS air chamber 130 at the front end of the eductor 140 according to the efficiency of the eductor 140 .

In this embodiment, when the pressure of the ALS air chamber 130 is reduced, the efficiency of the eductor 140 also decreases. In particular, when the pressure in the ALS air chamber 130 is reduced, it is installed at the front end of the eductor 140 . There is a fear that a pressure drop may occur in the regulator 150 .

The ship to which the air lubrication system according to an embodiment of the present invention is applied is installed on the compressed air injection line 120 , branched from the front end of the regulator 150 and bypass installed to bypass the regulator 150 . A line 121 is provided, and an on/off valve 123 is installed on the compressed air injection line 120 , specifically, on the front end and the bypass line 121 of the regulator 150 , respectively, and the pressure in the ALS air chamber 130 . When this is reduced, the pressure drop of the regulator 150 can be prevented in advance by supplying compressed air to the surface of the ship bottom of the hull without going through the regulator 150 .

Here, it may be preferable that a pressure transmitter 131 for measuring the pressure of compressed air in the ALS air chamber 130 is installed on one side of the ALS air chamber 130 .

In addition, when the ship of this embodiment uses all of the compressed air stored in the ALS air chamber 130 or insufficient, the above-described ALS compression unit 110 may be operated to supply compressed air to the surface of the ship bottom of the hull.

In the case of supplying compressed air to the surface of the ship bottom of the hull by operating the ALS compression unit 110, it is branched from the compressed air supply line 120 between the ALS air chamber 130 and the ALS compression unit 110, and the eductor Compressed air may be supplied through the auxiliary injection line 125 that joins the compressed air injection line 120 again at the rear end of the 140 .

Here, it may be preferable to additionally install a control valve 127 between the point where the eductor 140 and the auxiliary injection line 125 join on the compressed air injection line 120 , through which the compressed air It may prevent backflow and provide smooth compressed air supply.

A ship to which the air lubrication system according to an embodiment of the present invention is applied, the compressed air generating unit 160, the compressed air generating unit 160 and the ALS air installed inside the engine room (ER) provided on the stern side of the hull A nitrogen booster unit ( N2 booster unit) 180 and a second compressed air supply line 190 connecting the nitrogen booster unit 180 and the ALS air chamber 130 may be further included.

A ship to which the air lubrication system according to an embodiment of the present invention is applied, installs an ALS air chamber 130 capable of storing compressed air on the compressed air injection line 120, but compressed air from idle equipment provided inside the hull By generating and supplying to the ALS air chamber 130, the power consumption due to the operation of the air lubrication system of the ship to which the air lubrication system is applied is to be minimized.

Compressed air generating unit 160 is pre-installed inside the engine room (ER) provided on the stern side of the hull to generate compressed air for combustion of the engine (not shown), the compressed air generating unit 160 of this embodiment ) may be connected to the ALS air chamber 130 by the first compressed air supply line 170 to supply the compressed air generated by the compressed air generating unit 160 to the ALS air chamber 130 .

Here, on the first compressed air supply line 170, it may be preferable that a non-return valve 171 for preventing the reverse flow of the compressed air supplied from the compressed air generating unit 160 to the ALS air chamber 130 is installed. have.

As shown in FIG. 5 , the compressed air generating unit 160 includes a first compressor 161 installed inside the engine room ER and a first compressor 161 and a first storage line 162 by a first storage line 162 . It may include a first compressed air reservoir (Air reservoir) 163 that is connected to store the compressed air generated by the first compressor (161).

The first compressor 161 generates compressed air of about 8 bar to serve as a buffer to control pulsation due to a pressure change in the engine during operation of the engine, and to supply compressed air from the first compressor 161 The number of operation and operation time of the first compressor 161 can be reduced by the first compressed air reservoir 163 that is supplied and stored.

The compressed air generating unit 160 of this embodiment includes a second compressor 164 provided separately from the first compressor 161 in the engine room ER, and a second compressor ( 164) may further include a second compressed air reservoir 166 for storing the compressed air generated by the second compressor (164).

The second compressor 164 is used when the engine is initially started, and can generate compressed air of about 30 bar, and the compressed air generated by the second compressor 164 is stored in the second compressed air reservoir ( 166) can be stored.

This second compressor 164 is rarely used except for the purpose of initial driving of the engine, and serves to supplement the compressed air inside of the second compressed air reservoir 166 by the amount of compressed air used for initial driving of the engine. can do.

Here, the first compressed air supply line 170 is branched from the first storage line 162 connecting the first compressor 161 and the first compressed air reservoir 163 to be connected to the ALS air chamber 130 . The compressed air generating unit 160 is branched from the second storage line 165 connecting the second compressor 164 and the second compressed air reservoir 166 to the first compressed air supply line 170 and It may further include an auxiliary supply line 167 to be connected.

As described above, the first compressor 161 and the second compressor 164 constituting the compressed air generating unit 160 are idle equipment that are not operated except for the initial driving or buffering role of the engine. It can be advantageous to utilize idle equipment to operate the air lubrication system.

On the other hand, in the case of a ME-GI engine (not shown) that uses a high-pressure gas of 300 bar or more as fuel oil inside the engine room (ER), leakage of various pipes such as a fuel supply pipe (not shown) is tested. A nitrogen booster unit 180 for doing so may be provided.

The nitrogen booster unit 180 is pre-installed inside the electric motor room (EMR) for the leak test, and generates nitrogen gas (N2) pressurized to about 300 bar in the same way as the fuel supplied to the ME-GI engine. can

The nitrogen booster unit 180 of this embodiment may be connected to a gas valve train (GVT) 183 by a nitrogen supply line 181 , and the second compressed air supply line 190 is branched from the nitrogen supply line 181 . to be connected to the ALS air chamber 130 .

In the present embodiment, the GVT 183 is provided in the cargo compressor room CCR separately partitioned from the electric motor room EMR, and may serve to control fuel supplied to the ME-GI engine. .

In addition, when the GVT 180 is tested for leakage using the nitrogen gas generated by the nitrogen booster unit 180, the nitrogen gas pressurized to 300 bar is supplied from the nitrogen booster unit 180 to leak various pipes. tests can be performed.

Nitrogen booster unit 180 of this embodiment, similar to the compressed air generating unit 160, as idle equipment that is not normally operated, the ship of this embodiment, by utilizing this nitrogen booster unit 180, idle equipment In addition to the effect of operating the air lubrication system by utilizing

The second compressed air supply line 190 may be connected to the ALS air chamber 130 separately from the first compressed air supply line 170 , but preferably, the first compressed air supply line 170 and the second compressed air supply line 170 . One of the air supply lines 190 is connected to the ALS air chamber 130, and the other is connected (or joined) from the bow side, and is connected to the ALS air chamber 130 through a single pipe for compression. It may be desirable to supply air.

In other words, the first compressed air supply line 170 connects the compressed air generating unit 160 and the ALS air chamber 130 and connects the second compressed air supply line 190 to the first compressed air in the bow side area of the hull. It is configured to be connected to the supply line 170, or the second compressed air supply line 190 connects the nitrogen booster unit 180 and the ALS air chamber 130, and the first compressed air supply line 170 is connected to the bow side area. It may be configured to be connected to the second compressed air supply line 190 in.

On the other hand, in the ship to which the air lubrication system according to an embodiment of the present invention is applied, a controller (not shown) for controlling the supply of compressed air generated by the compressed air generating unit 160 and the nitrogen booster unit 180 . may further include.

In this embodiment, the first control valve 173 is further provided on the first compressed air supply line 170 close to the first compressor 161 , and the second control valve 167a is provided on the auxiliary supply line 167 . may be provided, and it may be preferable that the third control valve 191 be installed on the second compressed air supply line 190 .

The control unit is connected to the first control valve 173 and supplies the compressed air generated by the first compressor 161 only to the first compressed air reservoir 163 or ALS together with the first compressed air reservoir 163 . It can be controlled so that it can be supplied to the air chamber (130).

In addition, the control unit is connected to the second control valve 167a to supply the compressed air generated by the second compressor 164 only to the second compressed air reservoir 166 or to the second compressed air reservoir 166 and It can also be controlled so that it can be supplied to the ALS air chamber 130 together.

In this embodiment, the ALS air chamber 130, as described above, can store compressed air up to 30 bar therein, and receives compressed air supplied from the first compressor 161 through the control unit up to 8 bar. , from 8 bar to 30 bar, compressed air is supplied from the second compressor 164, and from 30 bar or more, compressed air may be supplied from the nitrogen booster unit 180.

Here, the control unit is connected to the pressure sensor 131 for measuring the pressure of the compressed air in the ALS air chamber 130 , the first compressor 161 , the second compressor 164 , and the nitrogen booster unit 180 , respectively. The operating time can be adjusted.

In addition, the control unit, the pressure sensor 131 provided on one side of the ALS air chamber 130 and the on/off valve 123 installed at the front end of the regulator 150 and the bypass line 121 on the compressed air injection line 12, respectively. Thus, when the pressure inside the ALS air chamber 130 drops, the pressure drop of the regulator 150 can be prevented in advance by supplying compressed air to the eductor 140 by bypassing the regulator 150 .

On the other hand, the ship to which the air lubrication system according to an embodiment of the present invention is applied, a seawater cooling system for cooling various equipment such as an engine installed on a hull, and an engine room (ER) to be generated inside A high expansion foam fire extinguishing system (High Expansion foam system) that can suppress various fires that can be, or prevent (Total fire fighting) may be further provided.

A ship to which the air lubrication system according to an embodiment of the present invention is applied, the stern sea chest 210 provided on the bottom surface of the stern side of the hull, and the cooler installed inside the engine room (ER) to cool fresh water with seawater as a refrigerant 220, a seawater cooling line 230 connecting the stern sea chest 210 and the cooler 220, and a seawater cooling pump installed on the seawater cooling line 230 to supply seawater to the cooler 220 ( 240) may be further included.

In this embodiment, the cooler 220 receives seawater from the stern sea chest 210 through the seawater cooling pump 240 installed on the seawater cooling line 230, and cools the seawater with a refrigerant to cool the fresh water. Cooled fresh water can be supplied to various equipment needed.

The configuration of cooling various equipment provided on the hull by using such seawater is a well-known technology, and a detailed description thereof will be omitted.

On the other hand, the stern sea chest 210, air bubbles may be introduced into the inside due to the operation of the air lubrication system, and when the air bubbles are introduced into the seawater cooling pump 240 together with seawater, the seawater cooling pump 240 ), the flow rate and pressure are lowered, so that malfunction or damage of the seawater cooling pump 240 may occur.

The ship to which the air lubrication system according to an embodiment of the present invention is applied installs a vent line 250 for discharging air bubbles flowing into the stern sea chest 210 to the outside of the hull, but the vent It may further include an ejector (Air ejector) 260 installed on the line (250).

The ejector 26 is a device for generating negative pressure (or vacuum) by receiving high-pressure and high-speed air, and as it receives high-pressure and high-speed air, the degree of vacuum may increase.

In this embodiment, the ejector 260, the compressed air generating unit 160, specifically the first compressed air reservoir 163 and the second compressed air reservoir 166 through a separate connection line 270 and may be connected, and a negative pressure may be generated using the compressed air generated from the compressed air generating unit 160 .

The ship of this embodiment may fundamentally block the inflow of air bubbles into the seawater cooling system through the ejector 260 .

The ship to which the air lubrication system according to an embodiment of the present invention is applied has an advantage in utilizing the above-described idle equipment, as well as providing a negative pressure on the vent line 250 to the inside of the stern sea chest 210 It may be effective to remove the incoming air bubbles.

In addition, the ship to which the air lubrication system according to an embodiment of the present invention is applied is a seawater storage unit 310 provided under the steering gear room (SG) of the hull separately from the stern sea chest 210 and , may further include a seawater supply pump 330 installed on the seawater supply line 320 connected to the seawater storage unit 310 .

In this embodiment, the seawater storage unit 310 may be located in the lower portion of the steering gear room (SG), specifically, the stern tank (A.P Tank) (unsigned), and the seawater supply pump 330 is the seawater storage unit ( 310) can be used to extinguish a fire in a residence or engine room by mixing foam with the seawater.

Here, at least a part of the seawater supply line 320 , in particular, the line connecting the seawater storage unit 310 and the seawater supply pump 330 is insulated to survive even if a fire occurs and is configured as a single pipe or , Minimize the damage caused by welding through butt welding or double sleeve joint welding by forming grooves or sleeves on both sides when it is difficult to provide with a single pipe and it may be desirable to configure it as a single pipe.

On the other hand, as described above, the draft (laden draft) in the state in which the cargo is loaded is generally 11.5 m, and in the ballast condition in which the ballast water is poured after the cargo is unloaded. The draft (Ballast draft) is about 9.4m, and the seawater supply pump 330 can only be lowered to about 11m from the bottom of the ship due to the hull structure of the ship.

In accordance with the ship's fire-fighting equipment-related standards or the classification, seawater should be supplied to the fire extinguishing system for 1 minute, and the fire in the engine room (ER) should be extinguished for 10 minutes, and fire fighting five times in a row. However, due to the seawater supply pump 330 through the seawater supply process, a lot of time may be delayed.

In order to solve this problem, in a ship to which the air lubrication system according to an embodiment of the present invention is applied, it is branched from the seawater supply line 320 between the seawater storage unit 310 and the seawater supply pump 330 and the ejector 260 and It may further include a suction line (Suction line) 340 to be connected.

The suction line 340 of this embodiment is connected to the ejector 260 that provides negative pressure, so that the supply of seawater to the foam generating unit 350 in the event of a fire in the engine room (ER) is completed within 1 minute required by the classification. It may serve to suck the air in the seawater supply line 320 so as to

In addition, in this embodiment, the control unit can supply appropriate compressed air to the ejector 260 through the control of the compressed air generating unit 160, and the air bubble introduced into the stern sea chest 210 outside of the hull It may be possible to selectively or concurrently use a mode for removing and discharging to the seawater and a mode for sucking air in the seawater supply line 320 .

In this embodiment, when the air lubrication system is operated in order to reduce frictional resistance during operation of the ship, the amount of air bubbles introduced into the stern sea chest 210 according to the ship speed may be different.

A ship to which the air lubrication system according to an embodiment of the present invention is applied provides a separate pressure measuring means (ie, a pressure sensor) (not shown) connected to the control unit at the front end of the seawater cooling pump 240 , and the pressure fluctuates When (Fluctation) or pressure drop (Low pressure) is detected, the compressed air generated by the first compressor 161 of the compressed air generating unit 160 is supplied to the ejector 260 and the air in the stern sea chest 210 is Bubbles can be sucked in and discharged to the outside.

Even in this process, when the air bubbles inside the stern sea chest 210 are not discharged well, that is, when fluctuations in pressure are continuously detected, the control unit supplies the compressed air generated by the second compressor 164 to the ejector 260 . By doing so, a larger amount of air bubbles can be sucked and discharged.

On the other hand, in the seawater supply pump 330 provided for suppressing the fire in the vessel in the normal condition of the vessel, the compressed air generated in the first compressor 161 is supplied to the ejector 260 through the control unit to supply seawater It is possible to maintain a negative pressure state in the supply pump 330 .

Here, when an emergency condition such as the initial driving of the engine or a fire in the engine room occurs, the control unit supplies the compressed air generated by the second compressor 164 to the ejector 260, thereby supplying seawater within a short time. The front end of the pump 330 may be filled with seawater, and it may have an advantageous effect that the seawater supply time for the fire extinguishing system is shortened.

The ship to which the air lubrication system according to an embodiment of the present invention is applied installs the ALS air chamber 130 on the compressed air injection line 170 and is pre-installed in each of the engine room (ER) and the electric motor room (EMR). By supplying compressed air to the ALS air chamber 130 using at least one of the compressed air generating unit 160 and the nitrogen booster unit 180, an air layer through air bubbles is formed on the surface of the ship's bottom to form an air layer for friction of the ship. Not only can the resistance be effectively reduced, but it can also have the effect of minimizing the power consumption due to the operation of the air lubrication system.

Furthermore, in ships to which the air lubrication system is applied, it is possible to prevent failure or damage of the seawater cooling pump 240 due to air bubbles, and to satisfy the classification requirements by solving the problem of delay in the seawater supply of the fire extinguishing system for fire suppression. can

Hereinafter, a method for supplying compressed air to a vessel to which the air lubrication system according to an embodiment of the present invention configured as described above is applied will be described.

The compressed air supply method of a ship to which an air lubrication system according to an embodiment of the present invention is applied is a compressed air generating unit 160 that generates compressed air for combustion of idle equipment installed on a hull, specifically, an engine, and a hull. The step of supplying compressed air to the ALS air chamber 130 using at least one of the nitrogen booster units 180 for generating pressurized nitrogen gas for a leak test of various pipes provided, and the ALS air chamber ( 130) may include the step of spraying the compressed air stored in the compressed air injection line 120 to the surface of the ship bottom of the hull.

In the step of spraying compressed air on the surface of the ship bottom of the hull, if all of the compressed air stored in the ALS air chamber 130 is used or insufficient, the ALS compression unit 110 is operated and the ALS air chamber 130 is disturbed. The compressed air generated in the ALS compression unit 110 may be supplied to the compressed air injection line 120 through a separate auxiliary injection line 125 .

In addition, when the pressure inside the ALS air chamber 130 decreases in the step of spraying the compressed air on the surface of the ship bottom of the hull, the compressed air stored in the ALS air chamber 130 is transferred to the rear end of the ALS air chamber 130 . Bypassing the provided regulator 150 can be supplied to the bottom surface of the hull.

On the other hand, in the compressed air supply method of a ship to which the air lubrication system according to an embodiment of the present invention is applied, the compressed air generating unit 160 is controlled through a separate control unit, and the control unit supplies appropriate compressed air to the ejector 260 . It may be possible to selectively or simultaneously use a mode for removing air bubbles flowing into the stern sea chest 210 by supplying it to the outside of the hull and a mode for sucking air in the seawater supply line 320 . .

In the mode of removing the air bubble introduced into the stern sea chest 210 by discharging it to the outside of the hull, the compressed air generating unit 160 to provide negative pressure on the vent line 250 connected to the stern sea chest 210 ) can be used with compressed air generated from

In addition, in the mode of sucking air in the seawater supply line 320 , the suction line branched from the seawater supply line 320 between the seawater storage unit 310 and the seawater supply pump 330 and connected to the ejector 260 . A negative pressure may be provided to the front end of the seawater supply pump 330 through 340 .

A ship to which the air lubrication system according to an embodiment of the present invention is applied is a ship including an LNGC (LNG Carrier) and an LNG RV (LNG Regasification Vessel), and a special ship including an LNG FSRU (Floating Storage and Regasification Unit). can be one

The above description is merely illustrative of the technical idea of the present invention, and those of ordinary skill in the art to which the present invention pertains may make various modifications, changes and substitutions within the scope without departing from the essential characteristics of the present invention. will be.

Accordingly, the embodiments disclosed in the present invention and the accompanying drawings are for explaining, not limiting, the technical spirit of the present invention, and the scope of the technical spirit of the present invention is not limited by these embodiments and the accompanying drawings .

In addition, the protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the scope equivalent thereto should be interpreted as being included in the scope of the present invention.

110: ALS compression unit
120: compressed air injection line
121: Bypass line
123: on-off valve
125: auxiliary injection line
130: ALS air chamber
131: pressure sensor (Pressure transmitter)
140: eductor (Eductor)
150: Regulator
160: compressed air generating unit
161: first compressor
162: first storage line
163: first compressed air reservoir (Air reservoir)
164: second compressor
165: second storage line
166: second compressed air reservoir
167: auxiliary supply line
167a: second control valve
170: first compressed air supply line
171: non-return valve
173: first control valve
180: nitrogen booster unit (N2 booster unit)
181: nitrogen supply line
183: Gas Vavle Train (GVT)
190: second compressed air supply line
191: third control valve
210: stern sea chest (Sea chest)
220: cooler
230: seawater cooling line
240: seawater cooling pump
250: vent line (Vent line)
260: ejector (Ejector)
310: seawater storage unit
320: seawater supply line
330: sea water supply pump
340: suction line (Suction line)
350: foam generating unit
CT: Cargo Tank
CD: Cofferdam
ER: Engine Room
CCR: Cargo Compressor Room
EMR: Electric Motor Room

Claims (19)

A ship to which an air lubrication system is applied to store liquefied gas cargo in a cargo tank provided in plurality along the longitudinal direction of the hull, and to reduce the frictional resistance of the hull by forming an air bubble on the surface of the bottom of the hull As,
A compressed air injection line for spraying compressed air on the surface of the bottom of the hull by connecting the ALS compression unit installed in the inner space of the bow side of the hull and a plurality of nozzles formed on the surface of the bottom of the hull;
an ALS air chamber installed on the compressed air injection line to store compressed air;
A nitrogen booster unit (N2 booster) that is installed inside the electric motor room provided on the upper part of the stern side cargo tank among the plurality of cargo tanks, and generates pressurized nitrogen gas for leak test of various pipes provided in the hull. unit); and
and a second compressed air supply line connecting the nitrogen booster unit and the ALS air chamber to supply the compressed air generated by the nitrogen booster unit to the ALS air chamber. The method of claim 1,
It is provided in the cargo compressor room partitioned from the electric motor room, and further comprises a GVT (Gas Valve Train) connected to the nitrogen booster unit by a nitrogen supply line,
The second compressed air supply line is branched from the nitrogen supply line and connected to the ALS air chamber. The method of claim 1,
A ship to which an air lubrication system is applied, further comprising a third control valve for controlling the supply of compressed air to the ALS air chamber on the second compressed air supply line. The method of claim 1,
an eductor installed at the rear end of the ALS air chamber on the compressed air injection line to suck the air inside the bow side hull; and
A vessel to which an air lubrication system is applied, further comprising a regulator installed at the front end of the eductor on the compressed air injection line to control the pressure of compressed air supplied to the eductor. 5. The method of claim 4,
a bypass line installed on the compressed air injection line, branched from the front end of the regulator, and installed to bypass the regulator; and
A vessel to which an air lubrication system is applied further comprising an on/off valve installed on the front end of the regulator and on the bypass line on the compressed air injection line, respectively. 5. The method of claim 4,
an auxiliary injection line branching from the compressed air injection line between the ALS air chamber and the ALS compression unit and rejoining the compressed air injection line by bypassing the eductor; and
A vessel to which an air lubrication system is applied further comprising a control valve installed between a point where the eductor and the auxiliary injection line join on the compressed air injection line. The method of claim 1,
a compressed air generating unit installed inside the engine room provided on the stern side of the hull to generate compressed air for combustion of the engine; and
Further comprising a first compressed air supply line for supplying the compressed air generated by the compressed air generator to the ALS air chamber,
The first compressed air supply line is a vessel to which an air lubrication system is applied, including being connected to the second compressed air supply line in the bow-side region of the hull. 8. The method of claim 7,
The compressed air generating unit,
a first compressor installed in the engine room and used to control compressed air supply to the engine while the engine is running; and
and a first compressed air reservoir connected to the first compressor by a first storage line to store compressed air generated by the first compressor,
The first compressed air supply line is branched from the first storage line and connected to the ALS air chamber. 9. The method of claim 8,
The compressed air generating unit,
a second compressor provided separately from the first compressor in the engine room and used when the engine is initially driven;
a second compressed air reservoir connected to the second compressor by a second storage line to store compressed air generated by the second compressor; and
A ship to which an air lubrication system is applied further comprising an auxiliary supply line branched from the second storage line and connected to the first compressed air supply line. 10. The method of claim 9,
The compressed air generating unit,
It is installed close to the first compressor on the compressed air supply line to supply the compressed air generated by the first compressor only to the first compressed air reservoir or to the ALS air chamber together with the first compressed air reservoir. a first control valve controlled to be able to; and
A second control installed on the auxiliary supply line and controlled to supply the compressed air generated by the second compressor only to the second compressed air reservoir or to the ALS air chamber together with the second compressed air reservoir Vessels with an air lubrication system further comprising a valve. The method of claim 1,
A vessel to which an air lubrication system is applied further comprising a pressure measuring sensor for measuring the pressure inside the ALS air chamber. 8. The method of claim 7,
A stern sea chest provided on the stern side of the hull (Sea chest);
a vent line (Vent line) for discharging the air bubbles introduced into the stern sea chest to the outside of the hull; and
A vessel to which an air lubrication system is applied further comprising an ejector installed on the vent line and generating a negative pressure using the compressed air generated from the compressed air generator. 13. The method of claim 12,
a seawater storage unit provided under the steering gear room of the hull separately from the stern sea chest;
a seawater supply pump installed on a seawater supply line connected to the seawater storage unit and mixing foam with the seawater stored in the seawater storage unit to extinguish a fire in a residence or the engine room; and
The ship to which the air lubrication system is applied further includes a suction line branched from the seawater supply line between the seawater storage unit and the seawater supply pump and connected to the ejector to suck air in the seawater supply line. 14. The method of claim 12 or 13,
Air lubrication system applied vessel further comprising a control unit for controlling the compressed air supply using the compressed air generator and the nitrogen booster unit. As a method of supplying compressed air to a ship to which the air lubrication system according to claim 1 is applied,
supplying compressed air to the ALS air chamber using at least one of the nitrogen booster unit and a compressed air generator that generates compressed air for combustion of an engine; and
Including the step of spraying the compressed air stored in the ALS air chamber to the surface of the bottom of the hull through the compressed air injection line,
In the step of spraying compressed air to the bottom surface of the hull,
When all of the compressed air stored in the ALS air chamber is used or insufficient, the ALS compression unit operates and the compressed air generated in the ALS compression unit is injected through a separate auxiliary injection line bypassing the ALS air chamber. A method of supplying compressed air for ships to which the air lubrication system supplied through the line is applied. 16. The method of claim 15,
In the step of spraying compressed air to the bottom surface of the hull,
When the pressure inside the ALS air chamber decreases, the compressed air stored in the ALS air chamber bypasses a regulator provided at the rear end of the ALS air chamber and supplies the surface of the bottom of the hull to the surface of the ship's hull. Applied compressed air supply method for ships. 16. The method of claim 15,
In the step of supplying compressed air to the ALS air chamber,
The compressed air generating unit has a mode for discharging and removing air bubbles flowing into the stern sea chest provided on the stern side of the hull to the outside of the hull through a separate control unit, and a seawater storage unit provided under the steering gear room of the hull and A method of supplying compressed air for a ship with an air lubrication system that is controlled so that selective or simultaneous use of the mode for sucking air in the seawater supply line connecting the seawater supply pump is possible. 18. The method of claim 17,
In a mode to remove the air bubble flowing into the stern sea chest by discharging it to the outside of the hull,
Compressed air supply method of a ship to which an air lubrication system using compressed air generated from the compressed air generator is applied to provide negative pressure on the vent line through an ejector installed on the vent line of the stern sea chest. 19. The method of claim 18,
In the mode of sucking air in the seawater supply line,
Compressed air supply method of a ship to which an air lubrication system is applied to provide negative pressure to the front end of the seawater supply pump through a suction line branched from the seawater supply line between the seawater storage unit and the seawater supply pump and connected to the ejector.

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