KR102099523B1 - Hull friction resistance reduction device and ship - Google Patents

Abstract

Provided is a hull friction resistance reduction device and a ship capable of effectively reducing the frictional resistance of a hull while suppressing the risk of air bubbles entering the propeller. A bubble blowing unit (36C, 36R, 36L) provided in a plurality in the width direction in front of the propeller (16), an adjusting mechanism (35) for adjusting the bubble blowing amount of the bubble blowing units (36C, 36R, 36L), and a control device (50) and inflow information acquisition means for acquiring information regarding the inflow of air bubbles (100) into the propeller (16). The control device 50 has an adjustment mechanism control section 52, and the adjustment mechanism control section 52 is disposed at least in front of the front of the propeller 16 when the bubble inflow information is acquired from the inflow information acquisition means. With respect to the bubble blowing unit 36C, the operation of the adjustment mechanism 35 is controlled to reduce the blowing amount of the bubble 100.

Description

Hull friction resistance reduction device and ship

The present invention relates to a hull friction resistance reduction device for reducing hull friction resistance by covering a ship bottom with air bubbles, and a vessel provided with the hull friction resistance.

At the time of navigation, a technique is known in which air bubbles are generated from the bow side toward the stern side, and the hull friction resistance is reduced by covering the ship bottom with the air bubbles.

As such a technique, there is the technique disclosed in Patent Document 1, for example. In the technology disclosed in Patent Literature 1, the navigation status determination unit 100 and the maritime determination unit 120 are provided, and control is made for ejection of air bubbles to the ship bottom 3 based on the current state of the ship or the sea. , E.g., when the wave height is greater than or equal to a predetermined value, the blowing of air bubbles is stopped (see paragraphs [0079]-[0083], [0097], etc. The signs in parentheses are used in Patent Document 1). Sign).

Patent Document 1: Japanese Patent Application Publication No. 2009-248611

However, in the technique of reducing the frictional resistance of the hull by air bubbles, a part of the air bubbles may flow into the stern propeller, especially during high-speed sailing. When air bubbles are introduced into the propeller, the propulsion force of the propeller is decreased, the hull vibration caused by the propeller vibration force caused by the propeller fluctuation pressure is increased, and the propeller erosion risk is increased.

In the technique disclosed in Patent Literature 1, various sensors are provided, and judgment of navigation conditions and resolution is made based on the detection results of these sensors, and control of ejection of air bubbles is performed based on this judgment. Since the inflow of air bubbles is not recognized as a problem, the problem cannot be solved.

The present invention has been devised in view of the above problems, and provides a hull friction resistance reduction device and a ship capable of effectively reducing the frictional resistance of the hull while suppressing the risk of air bubbles entering the propeller. It is aimed at.

(1) In order to achieve the above object, the hull friction resistance reducing apparatus of the present invention is provided in plural along the hull width direction in front of the propeller at the bottom of the ship, and the bubble ejecting unit for ejecting bubbles and the bubble ejecting unit Air bubble inflow information indicating that the air bubbles are introduced into the propeller or the air bubbles may be introduced into the propeller as a hull friction resistance reduction device having an adjustment mechanism for adjusting the air bubble ejection amount and a control device. And an inflow information acquiring means for acquiring, wherein the control device has an adjustment mechanism control unit that controls the operation of the adjustment mechanism, and the adjustment mechanism control unit does not acquire the bubble inflow information from the inflow information acquisition means. In this case, the adjustment is performed so that a predetermined amount of bubbles are ejected from each of the plurality of bubble ejecting units. When controlling the operation of the sphere while acquiring the bubble inflow information from the inflow information acquisition means, among the plurality of bubble ejection units, at least with respect to the bubble ejection unit disposed in front of the propeller, the ejection of the bubbles It is characterized in that the operation of the adjustment mechanism is controlled to reduce the amount more than the predetermined amount.

Here, when there are a plurality of bubble blowing units disposed in front of the front of the propeller, if at least one bubble blowing unit in front of the propeller is reduced with respect to the bubble blowing unit, the amount of bubble blowing is reduced to "at least. For the bubble blowing unit disposed in front of the front, it corresponds to "reducing the blowing amount of the bubble from a predetermined amount".

(2) The inflow information acquisition means is preferably inflow detection means for detecting the inflow of the bubbles into the propeller.

(3) When the bubble inflow information is acquired from the inflow information acquiring means, the adjustment mechanism control unit, among the plurality of bubble ejection units, at least with respect to the bubble ejection unit disposed in front of the propeller, the bubble It is desirable to stop the eruption.

(4) When the bubble inflow information is acquired from the inflow information acquiring means, the adjustment mechanism control unit, in the bubble ejection unit of the front of the propeller, only the bubble ejection unit in front of the propeller determines the amount of ejection of the bubbles. It is desirable to reduce it than a predetermined amount.

(5) The inflow detection means is provided in the imaging device for imaging the propeller and the control device, and determines whether or not the bubbles are flowing into the propeller based on the image information captured by the imaging device. It is preferable to include a judging section for performing.

(6) It is preferable that the imaging device is mounted on the ship bottom directly in front of the propeller.

(7) The imaging device is preferably arranged right next to the propeller.

(8) It is preferable that the said imaging device is arrange | positioned as a pair so that the propellers may be pinched from both sides in the width direction of the said ship.

(9) The inflow detection means is provided with the vibration detection means for detecting a vibration or a parameter correlated with the vibration of the propeller, and is provided in the control device, based on the detection information of the vibration detection means, the air bubbles with the propeller It is preferable to have a determination unit for determining whether or not is flowing.

(10) It is preferable that a plurality of the vibration detection means are provided along the width direction of the hull, and the determination unit performs the determination based on each detection information of the plurality of vibration detection means.

(11) When, among the plurality of vibration detecting means, there has been the vibration detecting means judged by the determination unit to be based on the detection information and the air bubbles are flowing into the propeller, the adjustment mechanism control unit is at least , It is preferable to reduce the blowing amount of the bubble from the predetermined amount with respect to the bubble blowing unit in front of the vibration detecting means that is determined that the bubble is flowing.

(12) It is preferable that the vibration detection means is a pressure sensor that exposes at least a detection end outside the ship above the propeller.

(13) It is preferable that the vibration detection means is an acceleration sensor disposed in a ship above the propeller.

(14) The propeller is provided at the center in the width direction of the hull, and it is preferable that the bubble ejection unit in front of the front is disposed at the center in the width direction of the hull.

(15) In the propeller, a plurality of juxtapositions are arranged along the width direction of the hull, the bubble ejection units are respectively disposed in front of the front of the plurality of propellers, and each of the plurality of propellers is provided with the inflow information acquisition means It is preferred.

(16) In order to achieve the above object, the ship of the present invention is characterized by comprising the hull frictional resistance reducing device according to any one of (1) to (15).

According to the present invention, when air bubbles inflow information indicating that air bubbles are introduced into the propeller or air bubbles may be introduced into the propeller is not acquired, a predetermined amount is obtained from each of the plurality of air bubble ejection units provided along the width direction of the hull. When the bubble inflow information is obtained while spraying the bubbles, the amount of bubbles ejected is reduced, at least with respect to the bubble ejection unit disposed in front of the propeller, thereby suppressing the risk of bubbles flowing into the propeller. , It is possible to reduce the frictional resistance of the hull.

In Fig. 1, Figs. 1A and 1B are schematic views showing the overall configuration of a ship as a first embodiment of the present invention, Fig. 1A is a side view, and Fig. 1B is a bottom view.
2 is a schematic view showing the configuration of a hull frictional resistance reducing device according to a first embodiment of the present invention.
In Fig. 3, Figs. 3A and 3B are schematic diagrams for explaining the determination method by the determination unit according to the first embodiment of the present invention, and are diagrams showing examples of images of propellers captured by a surveillance camera.
In Fig. 4, Figs. 4A and 4B are schematic views showing the main parts of the ship as the second embodiment of the present invention, Fig. 4A is a side view of the rear of the ship, and Fig. 4B is a rear view (the key is omitted).
In Fig. 5, Figs. 5A and 5B are schematic views for explaining a determination method by the determination unit according to the second embodiment of the present invention, and are diagrams showing examples of propeller images captured from the side by a surveillance camera. to be.
In Fig. 6, Figs. 6A and 6B are schematic views showing the main parts of the ship as the third embodiment of the present invention, Fig. 6A is a side view of the rear of the ship, and Fig. 6B is a rear view (the key is omitted).
7 is a schematic view showing a configuration of a hull frictional resistance reducing device according to a third embodiment of the present invention.
In Fig. 8, Figs. 8A, 8B, 8C, and 8D are schematic views for explaining the determination method by the determination unit according to the third embodiment of the present invention, and Fig. 8A is an example of the pressure fluctuation above the propeller. 8B, 8C, and 8D are diagrams showing an example of the frequency spectrum of the variable pressure above the propeller.
Fig. 9 is a schematic rear view showing the configuration of a main part of a ship as a fourth embodiment of the present invention (key is omitted).
10 is a schematic view showing the configuration of a hull frictional resistance reducing device according to a fourth embodiment of the present invention.
In Fig. 11, Figs. 11A and 11B are schematic diagrams for explaining the determination method by the judging section according to the fourth embodiment of the present invention, and the propellers on coordinates with the horizontal axis as the line width direction and the vertical axis as the variable pressure. It is a figure which shows an example of the upward variable pressure distribution.
In Fig. 12, Figs. 12A and 12B are schematic bottom views showing the configuration of a ship in a modified example of the present invention.
In Fig. 13, Figs. 13A and 13B are schematic bottom views showing the configuration of the stern side which is the main part of the ship in a modified example of the present invention.

Hereinafter, each embodiment of this invention is described with reference to drawings. In addition, each embodiment shown below is only an example and it is not intended to exclude the application of various modifications and techniques not specified in each embodiment below. The configuration of each of the following embodiments can be implemented in various modifications without departing from their gist.

In addition, in the following description, the bow 11 side (progression direction) of the ship 1 is set to the front, the stern 12 side is set to the rear, and the left and right sides are determined based on the front side, and the direction of gravity is downward. Then, the opposite will be described above. In addition, the direction perpendicular to the ship's front-rear direction (hereinafter also referred to as the "front-rear direction") X is set to the hull width direction Y (hereinafter also referred to as the "width direction" or "line-width direction"), and the center line about the width direction Y (CL ), The side closer to the inside, and vice versa, the side away from the center line CL will be described.

In addition, in the description of the devices and components mounted on the ship 1, the up and down directions, the left and right directions, and the front and rear directions are determined based on the state in which these devices and components are mounted on the ship 1.

[One. First embodiment]

[1-1. Ship's overall composition]

The entire structure of the ship as the first embodiment of the present invention will be described with reference to Figs. 1A and 1B.

1A and 1B are schematic views showing the overall configuration of a ship as a first embodiment of the present invention, FIG. 1A is a side view, FIG. 1B is a bottom view, and is a diagram showing an air system diagram for a hull frictional resistance reduction device.

1A and 1B, the ship 1 includes a hull 10, which is the main body of the ship 1, a control room 20 in which various control of the ship 1 is performed, and a hull friction resistance reduction. A device 30 is provided. The ship 1 is, but is not limited to, a flat bottom on which the bottom 13 is flat.

The hull 10 is provided with one or a plurality of propellers 16 (one in this embodiment) propelling the hull 10 at its rear portion (near the stern 12), and also at the rear of the propeller 16. , A key 17 for determining the direction of travel of the hull 10 is provided. The center of rotation C0 and the key 17 of the propeller 16 are both positioned on the center line CL in plan view.

The hull friction resistance reducing device 30 blows air from the ship bottom 13 to generate bubbles (hereinafter, also referred to as bubbles) 100 at the boundary between the ship bottom 13 and water, and the bubbles 100 By forming a bubble layer covering the ship bottom 13, the frictional resistance of the sailing ship 1 is reduced.

[1-2. Hull friction resistance reduction device]

[1-2-1. Overall configuration of hull friction resistance reduction device]

1A, 1B, and 2, the overall configuration of the hull frictional resistance reducing device 30 will be further described.

2 is a schematic diagram showing the configuration of the hull frictional resistance reducing device 30, and includes a block diagram showing the control configuration of the control device 50.

The hull friction resistance reducing device 30, as shown in Figs. 1B and 2, for example, is an air supply passage 31 configured by a blower or a compressor, and an air supply passage having one end connected to the air supply 31 (32), a flow adjustment valve 33 provided in the air supply passage 32, a plurality of (here six) branch supply pipes 34 branching from the other end side of the air supply passage 32, and each branch A shut-off valve (adjustment mechanism) 35 provided in the supply pipe 34, air bubble ejecting portions 36C, 36L, and 36R connected to the branch ends of each branch supply pipe 34, and a surveillance camera monitoring the propeller 16 A (imaging device) 40 and a control device 50 disposed in the control room 20 are provided.

Hereinafter, when the bubble blowing parts 36C, 36L, and 36R are not distinguished, the bubble blowing parts 36 are referred to.

Each bubble blowing part 36 is arrange | positioned at the front part of the ship bottom 13. Regarding the line width direction Y, the bubble blowing section 36C is on the center line CL, the bubble blowing section 36L is on the port side 14, and the bubble blowing section 36R is on the starboard side 15. , Respectively, and the bubble blowing portions 36C, 36L, and 36R are disposed over the substantially entire width of the ship bottom 13. With respect to the front-rear direction X, the bubble blowing portions 36C are disposed at the frontmost side, and the bubble blowing portions 36L and 36R are disposed at the same position behind the bubble blowing portions 36C. You may arrange the bubble blowing parts 36C, 36L, 36R side by side.

When the position of the bubble blowing part 36C is further described, the bubble blowing part 36C is located in front of the front of the propeller 16. Being located in front of the front of the propeller 16, the bubble 100 ejected from the bubble ejection portion 36C moves relatively to the rear of the hull 1 according to the hang of the ship 1, and the propeller 16 Refers to the location of the bubble ejection portion 36 flowing into the. Therefore, in this embodiment, when viewed from the plane, each center line of the bubble ejection portion 36C and the line width direction Y of the propeller 16 coincides with the center line CL of the hull 1 (i.e. , The center line of the line width direction Y of the bubble blowing section 36C and the center line of the line width direction Y of the propeller 16 coincide), and the center line of the line width direction Y of the bubble blowing section 36C , It is not essential to match the center line of the line width direction Y of the propeller 16.

For example, if the bubble blowing section 36C is located in front of the front of the propeller 16, the bubble blowing section 36C is such that at least a portion is included in the region A upstream of the propeller 16 shown in FIG. 1B. ) May be defined as being positioned, or the bubble ejection portion 36C is positioned such that at least a portion exists on the center line of the propeller 16, but is not limited thereto.

The bubble blowing section 36C is constituted by a plurality of (here two) bubble blowing units 36C-1 and 36C-2 juxtaposed along the line width direction Y. Similarly, the bubble blowing section 36L is constituted by a plurality of (here two) bubble blowing units 36L-1 and 36L-2 juxtaposed along the line width direction Y, and the bubble blowing section 36R Is composed of a plurality of (here, two) bubble ejection units 36R-1 and 36R-2 juxtaposed along the line width direction Y. Hereinafter, when the bubble ejecting units 36C-1 to 36R-2 are not distinguished, they are referred to as bubble ejecting units 36-u.

Each bubble blowing unit 36-u is composed of an air chamber 36a disposed inside the ship bottom 13 and a plurality of blowout holes 36b drilled through the ship bottom 13. The air chamber 36a has a rectangular parallelepiped box shape with an open bottom surface, and is disposed inside the ship bottom 13 in a posture toward the line width direction Y. The ejection hole 36b is surrounded by the air chamber 36a in front, rear, left, and right directions.

The opening degree of the flow adjustment valve 33 is controlled by the control device 50. By controlling the opening degree of the flow adjustment valve 33, the amount of bubble ejection from each of the bubble ejection portions 36C, 36L, and 36R is simultaneously controlled.

A branch supply pipe 34 is connected to each bubble ejecting unit 36-u, and a shut valve 35 is provided to each branch supply pipe 34, respectively. The shut valve 35 is an on-off valve, and is controlled by the control device 50 to be either fully open or fully closed. That is, when the shut valve 35 is controlled to be fully opened by the control device 50, air bubbles are ejected from the corresponding bubble ejecting unit 36-u, and the shut valve 35 is controlled by the control device 50. When it is controlled to be completely closed by, the blowing of air bubbles from the corresponding bubble blowing unit 36-u is stopped. Moreover, the shut valve 35 also functions as a backflow prevention valve which prevents seawater from flowing back from the stationary bubble ejection unit 36-u and entering the branch supply pipe 34.

The surveillance camera 40 is installed at the rear of the ship bottom 13, and is in a water-repellent state during hangover, thereby monitoring the inflow of air bubbles into the propeller 16. The surveillance cameras 40 are arranged in pairs on the oblique front of the propellers 16 so that the propellers 16 are pinched from both sides, and are paired to image the entirety of the propellers 16.

In addition, as long as the surveillance camera 40 can image the whole propeller 16, the installation location and number are not limited to the above.

[1-2-2. Control configuration of hull friction resistance reduction device]

2, 3A and 3B, the control structure of the control device 50 of the hull frictional resistance reduction device 30 will be described.

3A and 3B are schematic diagrams for explaining the determination method by the determination unit 51 according to the first embodiment of the present invention, and examples of images of the propeller 16 captured by the surveillance camera 40 It is a diagram shown. In addition, since the surveillance camera 40 photographs the propeller 16 from an oblique front, in practice, the image captured by the surveillance camera 40 becomes a perspective image of the propeller 16, and further, the hull 1 Although part of) is shown, in Figs. 3A and 3B, for convenience, the hull 1 is omitted with the front image of the propeller 16 being used.

As shown in FIG. 2, the control device 50 determines whether or not air bubbles are flowing into the propeller 16, and the shut-off valve 35 based on the determination result of the determination unit 51 and the determination unit 51. ) Is provided with a shut valve control unit (adjustment mechanism control unit) 52 for controlling the operation.

The determination unit 51 acquires image information captured by each surveillance camera 40 as illustrated in FIGS. 3A and 3B, interprets the image information, and binarizes the image, for example, based on brightness. By doing so, the bubble 100 is identified, and it is determined whether the bubble 100 is flowing into the bubble detection area R. The bubble detection area R is an area defined as the mutual between the bubble detection lines L1 and L2 set up and down of the propeller 16. In this embodiment, the bubble detection lines L1 and L2 are defined as positions spaced up and down by the propeller radius r from the center of rotation C0 of the propeller 16.

As described above, the front images of the propellers 16 are conveniently described in FIGS. 3A and 3B, but in reality, the surveillance camera 40 captures the propellers 16 from both the left and right sides, so that only one is used. Can only sufficiently image on the left and right sides. For this reason, the determination unit 51 analyzes the image information of both surveillance cameras 40, and the image information of either surveillance camera 40 is also bubbled into the bubble detection area R as shown in Fig. 3A ( When it indicates that 100) is not flowing, it is determined that the air bubbles 100 are not flowing into the propeller 16, and the image information of either surveillance camera 40 is bubbled as shown in FIG. 3B. When it is indicated that bubbles are flowing into the detection region R, it is determined that the bubbles 100 are flowing into the propeller 16.

In addition, the bubble detection lines L1 and L2 are equal to r '(= r + Δr, Δr> 0) by adding a margin Δr to the propeller radius r from the rotation center C0 of the propeller 16. It may be defined as a position spaced up and down. In this case, when the air bubbles are not flowing into the air bubble detection area R, the determination unit 51 determines that the air bubbles 100 are not flowing into the propeller 16, and there is no concern about the air bubbles. When bubbles are introduced into the detection region R, it is determined that there is a possibility that the bubbles 100 are introduced into the propeller 16 or the bubbles 100 are introduced into the propeller 16.

As described above, since the air bubbles 100 are introduced into the propeller 16 by the determination unit 51 based on the image information of the surveillance camera 40, the monitoring camera 40 and the determination unit 51 enable the determination of the present invention. Inflow detection means are configured. In addition, since detecting the inflow of the bubble stream 100 is to acquire the bubble inflow information indicating that the bubble stream 100 has flowed, the monitoring camera 40 and the determination unit 51 allow the inflow of the present invention. An inflow information acquisition means is configured.

When the shut-off valve control part 52 acquires the information to which the air bubbles 100 are not flowing from the determination part 51 to the propeller 16 (hereinafter also called normal time), all shut-off valves ( 35) is to be completely open. That is, the bubble blowing parts 36C, 36L, and 36R are put into operation. On the other hand, the shut valve control part 52 is located in front of the front of the propeller 16 when the information (bubble inflow information) that the bubble flow 100 flows into the propeller 16 from the determination part 51 is obtained. The shutoff valve 35 of the branch supply pipe 34 leading to the bubble blowing section 36C (bubble blowing units 36C-1 and 36C-2) to be completely closed, and the bubbles from the bubble blowing section 36C ( 100) is stopped (in other words, the blowing amount of the bubble 100 from the bubble blowing portion 36C is reduced than usual). That is, the bubble blowing section 36C is brought into a stopped state.

[1-3. Action and effect]

According to the hull frictional resistance reduction device 30 and the ship 1 as the first embodiment of the present invention, air bubbles from the image information captured by the surveillance camera 40 to the propeller 16 by the determination unit 51 It is determined whether or not the flow 100 is flowing, and the result of the determination is output to the shut valve control unit 52.

When the result of this determination is the determination that the air bubbles 100 are not flowing into the propeller 16, the shut valve control unit 52 completely opens all the shut valves 35 as shown in Fig. 1B. Thus, all of the bubble blowing units 36C-1 to 36B-2 are operated. Thus, most of the area of the ship bottom 1 can be covered by the air bubbles 100.

On the other hand, when the determination result of the determination part 51 is the determination that the air bubbles 100 are flowing into the propeller 16, the shut valve control part 52 shows the propeller 16 as shown in FIG. The shut valves 35 provided for the bubble blowing units 36C-1 and 36C-2 located in front of the front are completely closed, and other bubble blowing units 36L-1, 36L-2, 36R-1, The shut valve 35 provided for 36R-2) is set to fully open.

All or most of the bubbles 100 flowing into the propeller 16 are bubbles ejected from the bubble ejecting units 36C-1 and 36C-2 disposed in front of the propeller 16. Accordingly, by stopping the bubble ejection units 36C-1 and 36C-2 with the shut valve 35 provided for the bubble ejection units 36C-1 and 36C-2 completely closed, air bubbles to the propeller 16 ( 100) can be suppressed. Thereby, it is possible to suppress a decrease in propulsive force due to the inflow of the bubble 100 into the propeller 16, an increase in hull vibration due to the propeller excitation force, and an increase in erosion risk. In addition, since the bubble ejection units 36L-1, 36L-2, 36R-1, and 36R-2 in which the bubble 100 is not introduced into the propeller 16 are operated, air bubbles in a large area of the ship bottom 1 are bubbled ( 100).

Therefore, in the case of high-speed sailing, in which the bubble 100 is easily introduced into the propeller 16, the frictional resistance of the hull 1 can be reduced while suppressing the risk of the bubble 100 flowing into the propeller 16. You can.

[2. Second embodiment]

The hull friction resistance reduction device and the ship as the second embodiment of the present invention will be described with reference to Figs. 4A, 4B, 5A, and 5B. In addition, the same code | symbol is attached | subjected about the component same as 1st Embodiment, and the description is abbreviate | omitted.

4A and 4B are schematic views showing the main part of the ship as the second embodiment of the present invention, FIG. 4A is a side view of the rear of the ship, and FIG. 4B is a rear view (the key 17 is omitted).

5A and 5B are schematic diagrams for explaining the determination method by the determination unit according to the second embodiment of the present invention, and are diagrams showing examples of propeller images captured from the side by a surveillance camera.

[2-1. Configuration]

In the hull friction resistance reducing device and the ship of the present embodiment, the arrangement of the surveillance cameras 40 is different from the first embodiment.

Specifically, as shown in Figs. 4A and 4B, a monitoring camera 40 is arranged in pairs on both outer sides of the propeller 16 in the line width direction Y. In the present embodiment, the surveillance camera 40 is arranged right next to the propeller 16 (that is, in the same position with respect to the front-rear direction X), but if it is outside the propeller 16 in the line width direction Y, the propeller ( 16) may be arranged on the front side or the rear side.

In addition, each surveillance camera 40 is supported by a pair of brackets (support members) 40a that are stretched downward from the outer edge of the lower surface of the stern 12, respectively. If the mounting location can be secured to the hull 1, each surveillance camera 40 may be directly mounted to the hull 1, respectively.

Since the surveillance camera 40 is disposed close to the propeller 16, in the sinking state in Hangzhou, the air bubbles 100 enter the propeller 16 in particular (i.e., the imaging by the surveillance camera 40 is not performed). When it is most needed), it is conceivable that the air bubbles 100 are also introduced into the surveillance camera 40. If so, the monitoring camera 40 itself enters into the bubble 100, and it is concerned that the propeller 16 cannot be imaged clearly enough to interpret the image by being obstructed by the bubble 100.

Therefore, by arranging the surveillance camera 40 outside with respect to the line width direction Y of the propeller 16, the surveillance camera 40 is excluded from the traveling path of the bubbles 100 flowing into the propeller 16. Doing.

In addition, the risk that the air bubbles 100 from the bubble ejection portion 36C installed on the center line CL is introduced is reduced only by arranging the surveillance camera 40 outside the propeller 16, There is a risk that the bubbles 100 from the bubble blowing portions 36L and 36R installed on both sides of the bubble blowing portion 36C are introduced. For this reason, the surveillance camera 40 is arranged at the outer edge of the hull 1 as in the present embodiment so as to deviate from the downstream region of all the bubble ejection portions 36 including the bubble ejection portions 36L and 36R. It is preferred.

The image information shown in FIGS. 5A and 5B captured from the side by the surveillance camera 40 is image analyzed by the determination unit 51 (see FIG. 2) as in the first embodiment. That is, the determination unit 51 analyzes the image information of both surveillance cameras 40, and the image information of any surveillance camera 40 is also bubbled into the bubble detection area R as shown in Fig. 5A. ) Is not flowing, it is determined that the air bubbles 100 are not flowing into the propeller 16, and the image information of either surveillance camera 40 is shown in FIG. 5B, as shown in FIG. 5B. When air bubbles are introduced into R), it is determined that the air bubbles 100 are flowing into the propeller 16.

This other configuration is the same as that of the first embodiment, and thus description is omitted.

[2-2. Action and effect]

According to the hull frictional resistance reduction device and the ship as the second embodiment of the present invention, since the surveillance camera 40 is suppressed from entering the air bubbles 100, the clear image information without the influence of the air bubbles 100 is monitored. It can be acquired by (40). Therefore, it is possible to improve the detection accuracy of the inflow of the air bubbles 100 into the propeller 16 based on the clear image information, and more effectively, while suppressing the risk of the inflow of the air bubbles 100 into the propeller 16 , The frictional resistance of the hull 1 can be reduced.

[3. Third embodiment]

The hull frictional resistance reducing device and the ship as a third embodiment of the present invention will be described with reference to Figs. 6A, 6B, 7, 8A and 8B. In addition, the same code | symbol is attached | subjected about the component same as each said embodiment, and the description is abbreviate | omitted.

6A and 6B are schematic views showing the main part of the ship as a third embodiment of the present invention, Fig. 6A is a side view of the rear of the ship, and Fig. 6B is a rear view (the key 17 is omitted).

7 is a schematic diagram showing the configuration of the hull frictional resistance reducing device 30A according to the third embodiment of the present invention, and includes a block diagram showing the control configuration of the control device 50A.

8A, 8B, 8C, and 8D are schematic views for explaining a determination method by the determination unit according to the third embodiment of the present invention, and FIG. 8A is a view showing an example of pressure fluctuations above the propeller. 8B, 8C and 8D are diagrams showing an example of the frequency spectrum of the variable pressure above the propeller.

[3-1. Configuration]

The hull frictional resistance reduction device 30A and the ship 1A of the present embodiment, with respect to the hull frictional resistance reduction device 30 and the ship 1 of the first embodiment, are provided with pressure sensors (instead of the monitoring camera 40). The inflow of air bubbles 100 into the propeller 16 is detected using the vibration detection means 41. That is, in the first embodiment, the inflow information acquisition means and inflow detection means of the present invention are configured by the monitoring camera 40 and the determination unit 51, whereas in the present embodiment, the pressure sensor 41 and the determination unit ( 51A) constitutes the inflow information acquisition means and the inflow detection means of the present invention.

Specifically, as shown in FIGS. 6A, 6B, and 7, in the ship 1A of the present embodiment, a pressure sensor 41 is provided vertically above the propeller 16. The pressure sensor 41 is inserted into and fixed to a mounting hole processed in the bottom wall of the stern 12, and the detection end 411 is exposed outside the vessel to face the propeller 16 upwards.

As shown in Fig. 7, the hull friction resistance reducing device 30A includes an air supply source 31, an air supply passage 32, a flow rate adjustment valve 33, a branch supply pipe 34, and a shut valve ( 35), bubble ejection parts 36C, 36L, 36R, the pressure sensor 41, and a control device 50A disposed in the control room 20 (see FIG. 1A).

The control device 50A is based on the determination result of the determination unit 51A and the determination unit 51A, which determines whether air bubbles are flowing into the propeller 16 based on the detection result of the pressure sensor 41. A shut valve control unit 52A for controlling the operation of the shut valve 35 is provided.

The determination unit 51A obtains the pressure P above the propeller 16 from the pressure sensor 41 at a predetermined cycle, and time series data relating pressure P and time t as shown in FIG. 8A. (Pp), that is, grasp the pressure fluctuation. Then, the determination unit 51A periodically acquires the frequency spectrum of the variable pressure ΔP shown in FIGS. 8B, 8C, and 8D by FFT analysis of the time series data. Since the variable pressure ΔP is correlated with the vibration, and the larger the variable pressure ΔP, the larger the vibration, the vertical axis of FIGS. 8B, 8C, and 8D can be considered by substituting the vibration.

Here, FIG. 8B is a case where the hull friction resistance reducing device 30A is stopped, FIG. 8C is when the hull friction resistance reducing device 30A is operating, but the air bubbles 100 are not flowing into the propeller 16 , FIG. 8D is an example of the frequency spectrum of the fluctuation pressure ΔP when the hull friction resistance reducing device 30A is in operation and the air bubbles 100 are flowing into the propeller 16.

In the example shown in FIG. 8B, since the hull frictional resistance reducing device 30A is stationary, no air bubbles 100 are present around the propeller. Then, the NZ frequency (F1) defined by the rotational frequency (N) and the number of blades (Z) of the propeller (16), and the higher order components (F2, F3, F4) of the NZ frequency (F1), The peak values ΔP1, ΔP2, ΔP3, and ΔP4 of the variable pressure ΔP are generated, respectively. Higher order component (F2) is twice the frequency of NZ frequency (F1), higher order component (F3) is three times the frequency of NZ frequency (F1), higher order component (F4) is four times the frequency of NZ frequency (F1) to be. In the example shown in FIG. 8B, the peak value ΔP1 at the NZ frequency F1 represents the highest fluctuation pressure.

In the example shown in Fig. 8C, only the peak value ΔP1 at the NZ frequency F1 is generated, but this is because the hull frictional resistance reducing device 30A is operating. That is, as shown in Figs. 6A and 6B, the air bubbles 100 are interposed between the propeller 16 and the ship bottom 13 immediately above and immediately above the propeller 16. 100), the higher order components F2, F3, F4 of the NZ frequency F1 shown in Fig. 8B are attenuated, and only the peak value ΔP1 is detected as the variable pressure ΔP.

That is, the air bubbles 100 between the propeller 16 and the ship bottom 13 immediately above and immediately above the propeller 16 function as a damper, so that higher order components F2, F3 of the NZ frequency F1 , F4), the peak values ΔP2, ΔP3, and P4 are attenuated, and only the peak value ΔP1 of the NZ frequency F1 remains at a level equivalent to the peak value ΔP1 in FIG. 8B.

In the example shown in FIG. 8D, the bubble value 100 flows into the propeller 16 and the cavitation on the wing surface of the propeller 16 increases, so the peak value ΔP1 at the NZ frequency F1 is , It is increasing from the peak value (DELTA) P1 of the example shown in FIG. 8C (the hull friction resistance reducing device 30A is operating, but the bubble 100 is not flowing into the propeller 16). In addition, the peak values (ΔP2, ΔP3, ΔP4) of the higher order components (F2, F3, F4) of the NZ frequency (F1) are shown in FIG. 8C (hull friction resistance reducing device 30A is operating, but air bubbles are present). (100) is damped by the damper function of the air bubbles 100, as in the case where the propeller 16 is not introduced).

In the determination unit 51A, a preset alarm line La is stored. The alarm line La is a level at which the air bubbles 100 are likely to flow into the propeller 16 when the fluctuation pressure ΔP exceeds this level. Accordingly, the determination unit 51A determines that the bubble flow 100 is not flowing into the propeller 16 when the fluctuation pressure ΔP is equal to or lower than the alarm line La as shown in FIG. 8C, and FIG. 8D As shown in the figure, when the fluctuation pressure ΔP exceeds the alarm line La, it is determined that the air bubbles 100 are introduced into the propeller 16.

The shut valve control unit (adjustment mechanism control unit) 52A is configured in the same manner as the shut valve control unit 52 of the first embodiment, and the air bubbles 100 flow into the propeller 16 from the determination unit 51A. When information indicating that there is no information is obtained, all shut valves 35 are controlled to be fully opened, and when information indicating that air bubbles 100 are flowing from the determination unit 51A to the propeller 16 is obtained, the propeller 16 ) The shut valve 35 of the branch supply pipe 34 leading to the bubble ejection portion 36C located in front of the front side is completely closed.

This other configuration is the same as that of the first embodiment, and thus description is omitted.

[3-2. Action and effect]

According to the hull frictional resistance reducing device 30A and the ship 1A as the third embodiment of the present invention, the vibration generated by the inflow of the air bubbles 100 into the propeller 16 is changed by the pressure sensor 41 Since it detects directly as the pressure (ΔP), the inflow of air bubbles 100 into the propeller 16 with better precision than when the surveillance camera 40 is used as in the first and second embodiments described above Can be detected. That is, in the detection using the surveillance camera 40, when the periphery of the propeller 16 is dark, such as at night, or when the transparency of water is low, the identification accuracy of the air bubbles 100 decreases and the air bubbles to the propeller 16 ( Although the detection accuracy of the inflow of 100 may also be lowered, it is possible to detect the inflow of the air bubbles 100 into the propeller 16 with good accuracy even if it is a detection based on the fluctuation pressure ΔP. .

[3-3. etc]

In the above, as the vibration detection means, the pressure sensor 41 provided vertically above the propeller 16 was used, but instead of the pressure sensor 41, the acceleration sensor provided vertically above the propeller 16 was vibrated. You may use it as a detection means. When an acceleration sensor is used for the vibration detection means, the vibration of the hull 1 is detected, so that the detection end need not be exposed outside the ship. Therefore, it becomes unnecessary to process the mounting hole in the hull as in the case of using the pressure sensor 41, and mounting becomes easy.

The installation position of the pressure sensor 41 does not need to be strictly vertically upward of the propeller 16, and the propeller 16 is provided in a range that can detect the inflow of air bubbles 100 into the propeller 16 as variable pressure. You may deviate from the upper side of the vertical to the left and right.

[4. 4th embodiment]

The hull friction resistance reduction device and the ship as a fourth embodiment of the present invention will be described with reference to Figs. 9, 10, 11A, and 11B. In addition, the same code | symbol is attached | subjected about the component same as each said embodiment, and the description is abbreviate | omitted.

Fig. 9 is a schematic rear view showing a configuration of a main part of a ship 1B as a fourth embodiment of the present invention (the key 17 is omitted).

10 is a schematic diagram showing the configuration of the hull frictional resistance reducing device 30B according to the fourth embodiment of the present invention, and includes a block diagram showing the control configuration of the control device 50B.

11A and 11B are schematic diagrams for explaining the determination method by the determination unit 51B according to the fourth embodiment of the present invention, with the horizontal axis as the line width direction (Y) and the vertical axis as the variable pressure (ΔP). It is a figure which shows an example of the variable pressure distribution above the propeller 16 on coordinates. On the coordinates, the propeller 16 and the bubble ejection portions 36C, 36R, and 36L are virtually indicated by aligning the position with respect to the line width direction Y along the horizontal axis.

[4-1. Configuration]

The hull friction resistance reduction device 30B and the ship 1B of the present embodiment are a plurality of pressure sensors (vibration detection means) for the hull friction resistance reduction device 30A and the ship 1A of the third embodiment ( 41a to 41g) to detect the inflow of air bubbles 100 into the propeller 16. That is, in the third embodiment, the inflow information acquisition means and the inflow detection means of the present invention are constituted by one pressure sensor 41 and the determination unit 51A, while in the present embodiment, a plurality of pressure sensors 41a to 41g) and the determination unit 51B constitute the inflow information acquisition means and the inflow detection means of the present invention.

Specifically, in the ship 1B of the present embodiment, similar to the pressure sensor 41 of the third embodiment shown in Fig. 6A, pressure sensors 41a to each installed vertically above the propeller 16 when viewed from the side, respectively As shown in FIGS. 9 and 10, 41 g) are provided in plural along the line width direction Y. In the present embodiment, the pressure sensors 41a to 41g are provided over the entire entire width of the hull 10 including immediately above (vertical upward) the propeller 16.

As shown in Fig. 10, the hull friction resistance reducing device 30B includes an air supply source 31, an air supply passage 32, a flow rate adjustment valve 33, a branch supply pipe 34, and a shut valve ( 35), bubble ejection portions 36C, 36L, 36R, a plurality of pressure sensors 41a to 41g, and a control device 50B disposed in the control room 20 (see FIG. 1A). .

The control device 50B judges the determination unit 51B and the determination unit 51B for determining whether air bubbles are flowing into the propeller 16 based on the detection results of the plurality of pressure sensors 41a to 41g. A shut valve control unit (adjustment mechanism control unit) 52B for controlling the operation of the shut valve 35 based on the results is provided.

The determination unit 51B acquires the pressure P from each pressure sensor 41a to 41g at a predetermined cycle, and for each of these pressure sensors 41a to 41g, the maximum peak value of the variable pressure ΔP ( ΔP7 to ΔP13) are obtained. The maximum peak value means the maximum peak value among the peak values in the frequency spectrum. For example, in the example shown in FIGS. 8B, 8C, and 8D used in the description of the third embodiment, the peak value ΔP1 is the maximum. It becomes the peak value. Then, the determination unit 51B is shown in FIGS. 11A and 11B from position information and maximum peak values ΔP7 to ΔP13 of the line width direction Y of each pressure sensor 41a to 41g stored in advance. , Compensate these maximum peak values (ΔP7 to ΔP13) to obtain a peak distribution (Wp) in the line width direction (Y). Then, the determination unit 51B bubbles the alarm region Ra (shown by the diagonal lines in FIGS. 11A and 11B) exceeding the alarm line La of this peak distribution Wp with the propeller 16. The area 100 is introduced into and output to the shut valve control unit 52B.

In the shut valve control unit 52B, the predetermined shut valve 35 is completely closed to stop the bubble blowing unit 36-u in front of the alarm area Ra, and other bubble blowing units 36- u) works. In the example shown in Fig. 11A, from the bubble ejection units 36C-1, 36C-2 in front of the front of the alarm area Ra (that is, in front of the front of the propeller 16 into which the bubble 100 flows). The blowing of the bubble 100 is stopped, and the bubble 100 is injected from the other bubble blowing units 36R-1, 36R-2, 36L-1, and 36L-2. In the example shown in Fig. 11B, the bubble blowing unit 36C-2 in front of the front of the alarm area Ra (that is, in front of the front of the propeller 16 into which the bubble 100 flows) is stopped, and other The bubble ejection units 36R-1, 36R-2, 36C-1, 36L-1, and 36L-2 are operated.

Further, without using the peak distribution Wp or the alarm area Ra, the determination unit 51B is a pressure sensor in which the maximum peak values ΔP7 to ΔP13 of the variable pressure ΔP exceed the alarm line La. (41a-41g) is output to the shut valve control part 52B, and the shut valve control part 52B is a bubble blowing unit 36- in front of the pressure sensors 41a-41g exceeding the alarm line La. u) may be stopped.

In addition, the bubble ejection unit 36-u in front of the alarm area Ra is, in detail, viewed differently from the bubble ejection unit 36-u in front of the alarm area Ra in plan view. If is, the bubble ejection unit 36-u at least partially overlaps the alarm area Ra with respect to the line width direction Y. Likewise, the bubble blowing unit 36-u in front of the front of the pressure sensors 41a to 41g exceeding the alarm line La is, in detail, a pressure sensor exceeding the alarm line La in plan view. The bubble ejection unit 36-u in front of the front of (41a-41g), in other words, at least partially with respect to the line width direction (Y) to the pressure sensors (41a-41g) exceeding the alarm line (La) Refers to the bubble ejection unit 36-u that overlaps.

Moreover, you may use an acceleration sensor instead of a pressure sensor like 3rd Embodiment.

This other configuration is the same as that of the third embodiment, and description thereof is omitted.

[4-2. Action and effect]

According to the hull frictional resistance reduction device 30B and the ship 1B as the fourth embodiment of the present invention, in addition to the same effects as in the third embodiment, air bubbles are generated according to the peak distribution Wp of the variable pressure ΔP. It is possible to set the bubble blowing unit 36-u to stop 100 more finely, and more effectively suppress the frictional resistance of the hull 1 while suppressing the risk of the bubble 100 flowing into the propeller 16. Can be reduced.

[4-3. etc]

(1) In the above, the operation of the bubble blowing unit in front of the alarm area Ra is stopped, or the bubble blowing unit in front of the pressure sensors 41a to 41g exceeding the alarm line La. (36-u) was stopped, but when the alarm area Ra occurs or when there is at least one pressure sensor exceeding the alarm line La, the bubble ejection portion in front of the propeller 16 (36C) (air bubble ejecting units 36C-1 and 36C-2) may be stopped.

(2) In the fourth embodiment, as shown in FIG. 9, in addition to the pressure sensors 41c, 41d, and 41e positioned vertically above the propeller 16, in the line width direction W than the propeller 16 Pressure sensors 41a, 41b, 41f, and 41g located outside were used. On the other hand, only the pressure sensors 41c, 41d, and 41e positioned vertically above the propeller 16 may be provided.

In this case, the determination unit 51B determines the inflow of the air bubbles 100 based on the maximum peak values obtained from the detection results of these pressure sensors 41c, 41d, and 41e, and determines the shut-off valve control unit ( 52B). Alternatively, the determination unit 51B outputs the pressure sensors 41c to 41e whose maximum peak value of the variable pressure ΔP exceeds the alarm line La to the shut valve control unit 52B.

[5. etc]

(1) Modification 1

In the above-described first and second embodiments, an operator may view an image captured by the surveillance camera 40 by a monitor provided in the control room 20, and the surveillance camera 40 ) May be adjusted by remote operation from the control room 20.

In addition, the operator monitored by the monitor, "bubble flow 100 is flowing into the propeller 16 or air flow 100 is determined to be introduced into the propeller 16" (hereinafter referred to as bubble inflow judgment) May be provided, a manual switch may be provided to stop the bubble blowing section 36 by operator's manual operation. In this case, the manual switch corresponds to the inflow information acquisition means of the present invention.

(2) Modification 2

In each of the above-described embodiments, when the determination units 51, 51A, and 51B determine the bubble inflow, as an aspect of reducing the ejection amount of the bubble 100 from the bubble ejection unit 36C as usual, shut Although the valve 35 was completely closed, the blowing of the bubble 100 by the bubble blowing portion 36C was stopped (in other words, the adjustment mechanism of the present invention was configured by the shut valve 35), but the bubble blowing portion ( The aspect in which the blow-off amount of the bubble 100 from 36C) is reduced more than usual is not limited to this. For example, when the adjustment mechanism of the present invention is constituted by a regulating valve capable of continuously or stepwisely adjusting the opening degree instead of the shut valve 35, and the determination units 51, 51A, and 51B determine the bubble inflow. In, the opening degree of the regulating valve may be made narrower than that in the normal case (when the determination portions 51, 51A, and 51B do not judge the bubble inflow). In this case, even after the opening degree of the regulating valve is narrowed, if the bubbles 51, 51A, 51B still judge the bubble inflow, the opening degree of the regulating valve may be further narrowed.

(3) Modification 3

In each of the above-described embodiments, when the determination units 51, 51A, and 51B judged the bubble inflow, the blowing of the bubble 100 was stopped only for the bubble blowing unit 36C, but the bubbles of the bubble blowing unit 36C ( In addition to the blowing stop (or reducing the blowing amount) of 100), blowing stop (or reducing the blowing amount) of the bubble 100 may be performed on at least one of the bubble blowing portion 36L and the bubble blowing portion 36R.

Alternatively, even if the blowing of the bubble 100 of the bubble blowing portion 36C is stopped or the blowing amount is reduced, the determination units 51, 51A, and 51B still determine the bubble inflow (bubble to the propeller 16 ( In the case where the inflow of 100) has not been eliminated, additionally, at least one of the bubble ejection portion 36L and the bubble ejection portion 36R may be stopped or the amount of ejection of the bubble 100 may be reduced. Alternatively, in the case where the determination units 51, 51A, and 51B continue to perform bubble inflow determination, the order of the bubble ejection portion 36C, the bubble ejection portion 36L, and the bubble ejection portion 36R (or the bubble ejection portion) In the order of (36C), the bubble blowing section 36R, and the bubble blowing section 36L), the blowing stop of the bubble 100 or the reduction of the blowing amount may be added sequentially.

(4) Modification 4

This modification will be described with reference to Figs. 12A and 12B.

12A and 12B are schematic bottom views showing the configuration of the ship in this modification. In addition, the same code | symbol is attached | subjected about the component same as each embodiment, and the description is abbreviate | omitted.

In each of the above embodiments, the ship 1 is provided with one propeller 16 provided on the center line CL, but the present invention is not limited to this, and for example, the center line shown in FIGS. 12A and 12B. It can also be used for ships (1C, 1D) provided with propellers (16L, 16R) on both sides of (CL), respectively.

In the ship 1C shown in Fig. 12A, the rear portion of the ship bottom 13 is divided into two of the rear portions 13L and 13R, and propellers 16L and 16R are respectively provided at these rear portions 13L and 13R. . On the other hand, in the ship 1D shown in Fig. 12B, propellers 16L and 16R are provided protruding rearward from both left and right sides (both in the width direction) of the rear of the single ship bottom 13.

In the example shown in Figs. 12A and 12B, detection of the inflow of air bubbles (here, detection by the inflow information acquisition means using the monitoring camera 40 is not limited to this, but may be a pressure sensor or an acceleration sensor), and Control of the bubble ejection portions 36C, 36L, 36R is performed for each of the propellers 16L, 16R individually, and, for example, when the inflow of air bubbles is detected with respect to the propeller 16L on the left, the left When the blowing of the air bubbles 100 by the air blowing unit 36L in front of the propeller 16L is stopped (or the blowing amount is reduced), and the inflow of air bubbles is detected to the right propeller 16R. , The blowing stop of the bubble 100 by the bubble blowing unit 36R in front of the front of the propeller 16R on the right (or reducing the blowing amount) is performed.

In addition, when three or more propellers 16 are installed along the line width direction Y in the hull, air inflow detection means are provided for each propeller 16, and the propeller 16 is provided by air inflow detection means. When the inflow of air bubbles into the furnace is detected, when the inflow of air bubbles is detected, the eruption of the air bubbles 100 by the air bubble ejecting unit 36 in front of the propeller 16 where the inflow of air bubbles is detected (or reduction of the amount of air blow) do.

(5) Modification 5

This modification will be described with reference to Figs. 13A and 13B.

13A and 13B are schematic bottom views showing the configuration of the stern side, which is the main part of the ship in this modified example. In addition, the same code | symbol is attached | subjected about the component same as each embodiment, and the description is abbreviate | omitted.

In each of the above embodiments, the ship 1 is provided with one propeller 16 provided on the center line CL, but the present invention is not limited to this, and for example, the center line shown in FIGS. 13A and 13B. (CL) (or each on a plurality of lines along the center line CL) and a plurality (two in this modified example) of propellers can also be used for ships 1E, 1F provided before and after.

In the ship 1E shown in Fig. 13A, a pod propeller 18 is provided behind the propeller 16. The ford propeller 18 is provided with a propeller 18a to face the front propeller 16, and drives the propeller 16 by means of a built-in electric motor to generate propulsive force. The propeller 18a of the ford propeller 18 is arrange | positioned on the center line CL with the propeller 16.

In the ship 1F shown in Fig. 13B, propellers 16A and 16B are provided on the center line CL before and after, and these propellers 16A and 16B are rotationally driven in opposite directions by drive shafts composed of inner and outer axes. do.

In the example shown in Figs. 13A and 13B, detection of the inflow of air bubbles (in this case, detection by the inflow information acquisition means using the monitoring camera 40 is not limited to this, but may be a pressure sensor or an acceleration sensor). Although it is performed with respect to the front propellers 16 and 16A, it may be performed with respect to at least one of the two propellers, and it may be made to detect the inflow of air bubbles to the rear propellers 16B and 18a.

(6) As illustrated in the above-described modified examples (4) and (5), the arrangement of the propellers 16 and the number of installations of the propellers 16 are not limited.

(7) In the first and second embodiments, the bubble ejection units 36C-1 and 36C-2 in front of the front of the propeller 16 are based on the image information acquired by the two surveillance cameras 40. ) Was integrally controlled, but the bubble ejection units 36C-1 and 36C-2 may be separately controlled for each image information acquired by each surveillance camera 40.

That is, when the inflow of the bubble 100 into the propeller 16 is detected based on the image information of the surveillance camera 40 on the starboard 15 side of the propeller 16, the bubble ejection unit on the starboard 15 side If (36C-1) is stopped and the inflow of air bubbles 100 into the propeller 16 is detected based on the image information of the surveillance camera 40 on the port 14 side of the propeller 16, porting ( 14) You may make it stop the bubble blowing unit 36C-2 of the side.

In this case, for example, the inflow of air bubbles 100 into the propeller 16 is detected based on the image information of the surveillance camera 40 on the starboard 15 side, while the surveillance camera 40 on the port side 14 side is detected. When the inflow of the air bubbles 100 into the propeller 16 is not detected based on the image information of, the air bubble blowing unit 36C-1 on the starboard 15 side is stopped, and the air bubble blowing on the port side 14 is stopped. Unit 36C-2 is operated.

1, 1A, 1B, 1C, 1D, 1E, 1F ship
10 hull
11 players
12 stern
13 ship bottom
16, 16A, 16B, 16L, 16R propeller
18 ford propeller
Propeller of 18a Ford Propeller 18
20 control rooms
30, 30A, 30B hull friction resistance reduction device
32 air supply passage
34th quarter supply pipe
35 Shut valve (adjustment mechanism)
36C, 36L, 36R bubble jet
36C-1 ~ 36R-2 air bubble ejection unit
40 surveillance cameras (imaging unit)
40a bracket (support member)
41, 41a to 41g pressure sensor (vibration detection means)
411 detection stage
50, 50A, 50B control unit
51, 51A, 51B judgment unit
52, 52A, 52B shut valve control unit (adjustment mechanism control unit)
100 bubbles
Center line of CL hull (1, 1A, 1B, 1C, 1D, 1E, 1F)

Claims (18)

The ship bottom is provided with a plurality of bubbles along the hull width direction in front of the propeller, and includes a bubble blowing unit for blowing bubbles, an adjustment mechanism for adjusting the bubble blowing amount of the bubble blowing unit, and a control device. As a device,
And inflow information acquiring means for acquiring bubble inflow information indicating that the air bubbles are introduced into the propeller or the air bubbles may be introduced into the propeller,
The control device has an adjustment mechanism control unit that controls the operation of the adjustment mechanism,
The adjustment mechanism control unit,
When the bubble inflow information is not acquired from the inflow information acquisition means, the operation of the adjustment mechanism is controlled so that a predetermined amount of bubbles are ejected from each of the plurality of bubble ejection units,
When the bubble inflow information is acquired from the inflow information acquisition means, among the plurality of bubble ejection units, at least with respect to the bubble ejection unit disposed in front of the propeller, the amount of foam ejection is reduced from the predetermined amount To control the operation of the adjustment mechanism,
The inflow information acquisition means is inflow detection means for detecting the inflow of the bubbles into the propeller,
The inflow detection means,
An imaging device for imaging the propeller,
It is provided in the said control device, and based on the image information imaged by the said imaging device, it has the determination part which determines whether the bubble is inflowing into the propeller or whether there is a possibility that it may flow in,
The determination unit identifies bubbles by image analysis of the image information, and determines whether a bubble detection region is defined by a bubble detection line set up and down of the propeller, and whether or not the bubbles are flowing into the bubble detection region. Make a judgment,
Said imaging device is arrange | positioned so that it may deviate from the downstream area of all bubble ejection units, The hull friction resistance reduction device. delete The method according to claim 1,
When the bubble inflow information is acquired from the inflow information acquisition means, the adjustment mechanism control unit discharges the bubbles, at least of the bubble ejection units disposed in front of the front of the propeller, among the plurality of bubble ejection units. An apparatus for reducing frictional resistance of a ship, characterized in that it is stopped. The method according to claim 1 or claim 3,
When the bubble inflow information is acquired from the inflow information acquiring means, the adjustment mechanism control unit, of the bubble ejection units in front of the propeller, among the plurality of bubble ejection units, sets the amount of foam ejection to be greater than the predetermined amount. Reduced hull friction resistance device, characterized in that to reduce. delete delete The method according to claim 1 or claim 3,
The imaging device, characterized in that disposed next to the propeller, the frictional resistance reduction device for the hull. The method according to claim 1 or claim 3,
The imaging device is characterized in that the propellers are arranged in pairs so as to interlock from both sides in the width direction of the hull, and hull friction resistance reduction device. delete delete The ship bottom is provided with a plurality of bubbles along the hull width direction in front of the propeller, and includes a bubble blowing unit for blowing bubbles, an adjustment mechanism for adjusting the bubble blowing amount of the bubble blowing unit, and a control device. As a device,
And inflow information acquiring means for acquiring bubble inflow information indicating that the air bubbles are introduced into the propeller or the air bubbles may be introduced into the propeller,
The control device has an adjustment mechanism control unit that controls the operation of the adjustment mechanism,
The adjustment mechanism control unit,
When the bubble inflow information is not acquired from the inflow information acquisition means, the operation of the adjustment mechanism is controlled so that a predetermined amount of bubbles are ejected from each of the plurality of bubble ejection units,
When the bubble inflow information is acquired from the inflow information acquisition means, among the plurality of bubble ejection units, at least with respect to the bubble ejection unit disposed in front of the propeller, the amount of foam ejection is reduced from the predetermined amount To control the operation of the adjustment mechanism,
The inflow information acquisition means is inflow detection means for detecting the inflow of the bubbles into the propeller,
The inflow detection means,
Vibration detection means for detecting a vibration or a parameter correlated to the vibration of the propeller;
It is provided in the said control device, and based on the detection information of the said vibration detection means, the determination part which judges whether the bubble flows into the propeller is provided,
A plurality of the vibration detection means are provided along the width direction of the hull,
The determination unit performs the determination based on each detection information of the plurality of vibration detection means,
If, among the plurality of vibration detection means, there is the vibration detection means that is determined by the determination unit based on the detection information to flow the air bubbles into the propeller, the adjustment mechanism control unit, at least, the air bubbles The hull friction resistance reducing apparatus, characterized in that for the bubble ejection unit in front of the vibration detecting means determined to be flowing in, the amount of ejection of the bubbles is reduced from the predetermined amount. The method according to claim 11,
The vibration detecting means is a pressure sensor that exposes at least a detection end outside the ship in the upper side of the propeller, wherein the hull friction resistance reduction device. The method according to claim 11,
The vibration detection means is an acceleration sensor disposed in the ship above the propeller, characterized in that the hull friction resistance reduction device. The method according to any one of claims 11, 12 and 13,
The propeller is provided at the center in the width direction of the hull, and the bubble ejection unit in front of the front is arranged in the center in the width direction of the hull, hull friction resistance reduction device. The method according to any one of claims 11, 12 and 13,
In the propeller, a plurality of juxtapositions are arranged along the width direction of the hull, the bubble ejection units are respectively disposed in front of the front of the plurality of propellers, and the inflow information acquisition means is provided in each of the plurality of propellers. Hull friction resistance reduction device. The ship provided with the hull frictional resistance reduction device in any one of Claims 11, 12, and 13. A ship comprising the hull friction resistance reducing device according to claim 14. A ship comprising the hull frictional resistance reducing device according to claim 15.

Images