JP2016101855A - In-wave resistance increment alleviation bow shape and vessel having in-wave resistance increment alleviation bow shape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an in-wave resistance increment alleviation bow shape that can alleviate an in-wave resistance increment even when a vessel remains ballasted by focusing on a wave or a static water-level elevated position and a vessel having an in-wave resistance increment alleviation bow shape.SOLUTION: A bow shape having a bow valve 20 at a bow part 10 of a vessel comprises the formation of stem lines 11 of the bow valve 20 in two upper and lower steps to project a lower stage valve 21 forward of an upper stage valve 22, and to keep a top face 21a of the lower stage valve 21 positioned above a ballast state static water-level elevated position Athat is a water-level swelling position generated when a vessel travels under flat water in a wave-free state at a navigation speed set when designed as a representative speed for every vessel on sailing in a vessel ballast state, and positioned such that the wave overcomes the top face 21a of the lower stage valve 21 when the vessel sails at the navigation speed.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a wave resistance increasing / reducing bow shape that reduces an increase in wave resistance of a ship and a ship having a wave resistance increasing / reducing bow shape.

A bow valve provided on a ship such as a large-sized ship is exposed from the sea surface in a ballast state, which causes an increase in resistance in waves during traveling in the ballast state.
Here, in Patent Document 1, in the swelled hull form, the bow perpendicular line is located behind the intersection of the inflated surface of the ballast state and the fore material front edge formed substantially perpendicular to the inundated surface, and in the ballast state It is disclosed that a spherical valve having a diameter substantially equal to that of a bow flooding projects forward from the front edge of the bow material under a flooded line in a ballast state to improve propulsion performance.
Patent Document 2 discloses a full load valve having a top surface that does not immerse in water during ballast travel in a large ship, and a ballast valve that protrudes from the full load valve and is completely submerged during ballast travel. And the ballast flooded water line shape of the ballast valve is connected to the hull part almost linearly and sharpened at the tip to reduce hull resistance during ballasting. Yes.
Further, Patent Document 3 discloses a first bow valve for reducing wave resistance during navigation in a full flooded state, and a wave making during navigation in a ballast flooded state disposed below the first bow valve. There is disclosed a hull form with a bow valve with a second bow valve that reduces resistance.

Japanese Utility Model Publication No. 49-31352 JP 61-291286 A Microfilm of Japanese Utility Model No. 58-25430 (Japanese Utility Model Publication No. 59-131394)

By the way, when traveling in a ballast state, if the ship speed or wave height changes, the way the wave is applied to the bow valve changes. FIG. 12 is a side view of the bow portion of a ship having a conventional shape bow valve. For example, as shown in this figure, the bow 10, it takes the top of the bow valves when the boat speed height is large waves X _L comes at a high speed, slightly larger waves X height is at the medium speed is the boat speed relates to a central portion of the bow bulb when _M comes, according to the lower part of the bow valves when the boat speed comes a wave X _S wave height is small when the low speed. Conventionally, it has been considered that the resistance in waves increases monotonously with ship speed.
On the other hand, as a result of experiments on a ship having a bow valve, the inventors have shown that the wave resistance increases monotonously up to a certain ship speed, as shown in the relationship between ship speed and wave resistance increase in FIG. However, it has been found that when it exceeds the certain ship speed, it decreases monotonously. In FIG. 13, the horizontal axis represents the ship speed indicated by the Froude number (Fn), and the vertical axis represents the wave resistance increase coefficient (K _AW ). It can be seen that the wave resistance increase coefficient (K _AW ) monotonically increases until Fn = 0.13, and monotonically decreases when Fn = 0.13.
When the boat speed exceeds a certain value, the wave resistance decreases monotonically because the waves cannot get over the bow valve when the boat speed is slow, but when the boat speed is high, the wave height increases and the bow valve is overcome. It is considered that the increase in resistance in waves can be mitigated by adopting a valve shape that takes into account the wave and the static water level rising position.
However, the inventions described in Patent Document 1 to Patent Document 3 do not alleviate the increase in resistance in waves due to the valve shape focusing on the waves and the static water level rising position.

  Therefore, the present invention pays attention to the wave and the static water level rising position, and can reduce the increase in wave resistance even if the ship is in a ballast state. It aims at providing the ship which has.

  In the bow shape corresponding to claim 1, the bow shape having a bow valve at the bow portion of the ship, the stem line of the bow valve is formed in two upper and lower stages, and the lower valve is the upper valve. The upper surface of the lower valve travels in plain water where there is no wave at the nautical speed set at the time of design as a typical speed for each ship when traveling in the ballast state of the ship. It is formed so that the wave is over the upper surface of the lower valve when traveling at nautical speed and above the ballast state / static water level rising position that is the rising position of the water surface that occurs when . According to the first aspect of the present invention, when traveling in a ballast state, the wave can get over the lower valve even when the wave applied to the bow valve is small at the voyage speed (high speed). If the wave applied to the bow valve is large even at medium speed, the wave can get over the lower valve. Therefore, waves are lower valves for small waves to large waves, which are factors that increase resistance in waves during navigation speed (high speed) in ballast conditions, and for large waves at low to medium speeds. Since the upper surface of the can be overcome, an increase in resistance in waves can be reduced.

  The present invention according to claim 2 is characterized in that the inflection region at the upper end of the lower valve of the stem line is formed so as to be located above the still water surface position when the vessel is in a ballast state. . According to the second aspect of the present invention, it is possible to reliably obtain an effect of reducing the increase in resistance in waves by traveling over the bow valve during traveling in the waves in a ballast state.

  The present invention according to claim 3 is characterized in that a gooseneck shape is formed in which the upper surface of the lower valve once rises from the upper end of the tip toward the rear and then descends and rises again to connect to the upper valve. According to the third aspect of the present invention, it is possible to make the upper surface of the lower valve, which is the wave climbing portion, wider.

  The present invention according to claim 4 is a full load state that is a raised position of the water surface that occurs when the upper surface of the upper valve travels in flat water where there is no wave at the voyage speed when traveling in the full load state of the ship. It is formed so as to be positioned below the static water level rising position. According to the fourth aspect of the present invention, the effect of reducing the wave resistance by the bow valve can be obtained with certainty during traveling in the full load state.

  The present invention according to claim 5 is characterized in that the upper valve is partially re-projected forward. According to the fifth aspect of the present invention, it is possible to widen the portion where the wave of the upper valve rides, and in the state where a large wave is generated over the upper valve, the effect of reducing the wave resistance by the bow valve is enhanced. Can do. In addition, when traveling in a full load state, the effect of reducing the wave resistance due to the bow valve can be maintained equivalent to that of the conventional bow valve.

  7. A bow shape corresponding to claim 6, wherein the bow shape has a bow valve at the bow portion of the ship, the bow valve frame line is formed in two upper and lower stages, and the lower valve is the upper valve. The water is projected in the width direction and the upper surface of the lower valve is in the flat water where there is no wave at the nautical speed set at the time of design as a typical speed for each ship when traveling in the ballast state of the ship. It is formed so that the wave gets over the upper surface of the lower valve when traveling at nautical speed, and above the ballast state / static water level rising position, which is the rising position of the water surface generated when traveling And According to the sixth aspect of the present invention, when traveling in a ballast state, at the time of navigation speed (high speed), even if the wave applied to the bow valve is small, the wave can get over the lower valve, and If the wave applied to the bow valve is large even at medium speed, the wave can get over the lower valve. Therefore, waves are lower valves for small waves to large waves, which are factors that increase resistance in waves during navigation speed (high speed) in ballast conditions, and for large waves at low to medium speeds. Since the upper surface of the can be overcome, an increase in resistance in waves can be reduced.

  The present invention according to claim 7 is characterized in that the inflection portions at the upper ends of both sides of the lower valve of the frame line are formed so as to be located above the still water surface position when the ship is in a ballast state. To do. According to the present invention as set forth in claim 7, it is possible to reliably obtain an effect of reducing the increase in resistance in waves by traveling over waves at the bow valve during traveling in the waves in a ballast state.

  The present invention according to claim 8 is characterized in that it has a gooseneck shape in which the upper surface of the lower valve once rises from the upper end of the tip toward the rear and then descends and rises again to connect to the upper valve. According to the eighth aspect of the present invention, it is possible to make the upper surface of the lower valve, which is the wave climbing portion, wider.

  The present invention according to claim 9 is a full load state where the upper surface of the upper valve is a raised position of the water surface that occurs when traveling in flat water where there is no wave at sea speed when traveling in a full load state of the ship. It is formed so as to be positioned below the static water level rising position. According to the ninth aspect of the present invention, the effect of reducing the wave resistance by the bow valve can be obtained with certainty during traveling in the full load state.

  The present invention according to claim 10 is characterized in that an upper angle is set larger than a lower angle as an angle formed by a tangent line when the lower valve is viewed in plan. According to the tenth aspect of the present invention, the portion of the lower valve where the wave rides can be widened, and the increase in resistance in the waves can be further reduced.

  The present invention according to claim 11 is characterized in that the upper valve is partially re-extended in the width direction. According to the present invention as set forth in claim 11, it is possible to widen the portion where the wave of the upper valve rides, and in the state where a large wave is generated over the upper valve, the effect of reducing the resistance in waves by the bow valve is enhanced. Can do. In addition, when traveling in a full load state, the effect of reducing the wave resistance due to the bow valve can be maintained equivalent to that of the conventional bow valve.

  The present invention according to claim 12 is characterized in that a projection for inducing wave making is formed on the bow valve. According to the twelfth aspect of the present invention, the wave applied to the bow valve is induced by the protrusion, and the wave can easily get over the bow valve even at medium speed and low speed. can do.

  The present invention according to claim 13 is characterized in that the projection can be accommodated and extended in the width direction of the ship. According to the thirteenth aspect of the present invention, for example, when the protrusion is below the water surface, it is accommodated, and an increase in frictional resistance due to the protrusion can be reduced.

  In a ship having a bow shape that increases and reduces resistance in waves corresponding to claim 14, the bow shape that increases and reduces resistance in waves is adopted. According to the fourteenth aspect of the present invention, it is possible to reduce an increase in resistance in waves in a ship.

  The present invention according to claim 15 is characterized in that the ship is an enlarged ship. According to the fifteenth aspect of the present invention, it is possible to reduce an increase in resistance in waves in an enlarged ship.

  The present invention described in claim 16 is characterized in that the speed setting means of the ship is configured to be able to set a speed corresponding to a reduction in resistance in waves including a voyage speed (high speed). According to the sixteenth aspect of the present invention, it is possible to easily set the speed of the ship so that the waves are positioned over the upper surface of the lower valve. Therefore, the effect of reducing the increase in resistance in waves by the bow valve can be obtained with certainty.

  According to the present invention, when traveling in a ballast state, when sailing speed is high (high speed), even if the wave applied to the bow valve is small, the wave can get over the lower valve, and even at low speed to medium speed, the bow When the wave applied to the valve is large, the wave can get over the lower valve. Therefore, waves are lower valves for small waves to large waves, which are factors that increase resistance in waves during navigation speed (high speed) in ballast conditions, and for large waves at low to medium speeds. Since the upper surface of the can be overcome, an increase in resistance in waves can be reduced.

  In addition, if the inflection part at the upper end of the lower valve of the stem line is formed so as to be positioned above the still water surface position when the ship is at rest in the ballast state, traveling in the waves in the ballast state At times, it is possible to reliably obtain the effect of reducing the increase in resistance in the waves due to the waves getting over the bow valve.

  In addition, when the upper surface of the lower valve has a gooseneck shape that once rises from the top of the tip toward the rear and then descends and rises again to connect to the upper valve, the upper surface of the lower valve that is the wave ride-up part Can be made wider.

  The upper surface of the upper valve is higher than the full load / static water level rise position, which is the rising position of the water surface that occurs when running in flat water where there is no wave at the voyage speed when the ship is running in the full load state. When it is formed so as to be positioned below, it is possible to reliably obtain the wave resistance reduction effect by the bow valve during traveling in the full load state.

  In addition, when the upper valve is partially re-projected forward, it is possible to widen the part where the wave of the upper valve rides, and in the state where a large wave is generated over the upper valve, Resistance reduction effect can be enhanced. In addition, when traveling in a full load state, the effect of reducing the wave resistance due to the bow valve can be maintained equivalent to that of the conventional bow valve.

  Also, it has a bow shape with a bow valve at the bow of the ship, the bow valve frame line is formed in two upper and lower stages, the lower valve is projected in the width direction from the upper valve, and the upper surface of the lower valve is The ballast state / static state that is the rising position of the water surface that occurs when traveling in plain water where there is no wave at the nautical speed set at the time of design as a typical speed for each ship when traveling in the ballast state of the ship If it is formed so that the waves are over the upper surface of the lower valve when traveling at a voyage speed and above the target water level rise position, the voyage speed (high speed) will be Even if the wave applied to the bow valve is small, the wave can get over the lower valve, and if the wave applied to the bow valve is large even at low to medium speed, Valve can be waves overcome the. Therefore, waves are lower valves for small waves to large waves, which are factors that increase resistance in waves during navigation speed (high speed) in ballast conditions, and for large waves at low to medium speeds. Since the upper surface of the can be overcome, an increase in resistance in waves can be reduced.

  In addition, if the inflection part at the upper end on both sides of the lower valve of the frame line is formed so as to be located above the still water surface position when the ship is stationary in the ballast state, During traveling, it is possible to reliably obtain the effect of reducing the increase in resistance in waves due to the waves getting over the bow valve.

  In addition, when the upper surface of the lower valve has a gooseneck shape that once rises from the top of the tip toward the rear and then descends and rises again to connect to the upper valve, the upper surface of the lower valve that is the wave ride-up part Can be made wider.

  The upper surface of the upper valve is higher than the full load / static water level rise position, which is the rising position of the water surface that occurs when running in flat water where there is no wave at the voyage speed when the ship is running in the full load state. When it is formed so as to be positioned below, it is possible to reliably obtain the wave resistance reduction effect by the bow valve during traveling in the full load state.

  In addition, when the upper angle is set larger than the lower angle as the angle formed by the tangent line in a plan view of the lower valve, the wave rising portion of the lower valve can be widened. The increase in medium resistance can be further reduced.

  In addition, when the upper valve is partially re-extended in the width direction, the part where the wave of the upper valve rides can be widened, and a large wave that can overcome the upper valve, such as when driving at cruising speed in a ballast state. In a state where the occurrence of the wave, the effect of reducing the wave resistance by the bow valve can be enhanced. In addition, when traveling in a full load state, the effect of reducing the wave resistance due to the bow valve can be maintained equivalent to that of the conventional bow valve.

  In addition, if a projection that induces wave formation is formed on the bow valve, the wave is induced on the bow valve by the projection, making it easier for the wave to get over the bow valve even at medium and low speeds. The resistance increase reduction effect can be increased.

  Further, when the projection is configured to be housed and extended in the width direction of the ship, for example, when the projection is below the water surface, the projection can be accommodated to reduce an increase in frictional resistance due to the projection.

  In addition, when the bow shape is used to reduce the increase in wave resistance, the increase in wave resistance can be reduced in the ship.

  Further, when the ship is an enlarged ship, an increase in resistance in waves can be reduced in the enlarged ship.

  In addition, when the speed setting means of the ship is configured so that the speed corresponding to the increase in resistance in waves including the voyage speed (high speed) can be set, the wave will be over the upper surface of the lower valve. The speed of the ship can be set easily. Therefore, the effect of reducing the increase in resistance in waves by the bow valve can be obtained with certainty.

The figure which shows the bow shape reduction increase resistance in the wave by one Embodiment of this invention. Diagram explaining the relationship between ship speed and wave in the bow shape with reduced resistance increase in the same wave Diagram explaining the definition of wave height in the bow shape to reduce resistance increase in the same wave Figure showing the increase in resistance to waves in the wave due to the bow shape The figure which shows the bow shape reduction increase resistance in the wave by other embodiment of this invention. The figure which shows the bow shape reduction increase resistance in waves by other embodiment of this invention. The figure which shows the bow shape reduction increase resistance in waves by other embodiment of this invention. The figure which shows the bow shape reduction increase resistance in waves by other embodiment of this invention. The figure which shows the bow shape reduction increase resistance in waves by other embodiment of this invention. The figure which shows the bow shape reduction increase resistance in waves by other embodiment of this invention. The figure which shows the bow shape reduction increase resistance in waves by other embodiment of this invention. The figure which shows the state of the wave concerning the bow valve of the conventional shape The figure which shows the relationship of the ship speed-wave resistance increase in the bow valve of the conventional shape

Hereinafter, a ship having a bow shape having an increased resistance in waves and a bow shape having an increased resistance in waves according to an embodiment of the present invention will be described.
1A and 1B are diagrams showing a bow shape of an increase in resistance to waves according to an embodiment of the present invention, in which FIG. 1A is a side view and FIG. 1B is a front view. 2 is a diagram for explaining the relationship between the ship speed and the wave in the bow shape with increased resistance in the same wave, FIG. 3 is a diagram for explaining the definition of the wave height in the bow shape with increased resistance in the wave, and FIG. It is a figure which shows the resistance increase reduction in waves by the bow shape reduction increase in middle resistance.

As shown in FIG. 1, the bow shape in which the increase in resistance in waves according to the present embodiment is a bow shape having a bow valve 20 at the bow portion 10 of the ship. 1 (a) and 1 (b), B indicates a still water surface position at rest, which is a draft line in a ballast state, C indicates a full load draft line, and in FIG. 1 (b), a one-dot chain line Y indicates the center of the hull. A line is shown.
The stem line 11 of the bow valve 20 is formed in two upper and lower stages, the lower valve 21 protrudes forward from the upper valve 22, and the upper surface 21a of the lower valve 21 is different for each ship when traveling in the ballast state of the ship. water surface above the ballast condition, the static water level raised position a _S a climax position occurring when traveling flat water at cruise speed that has been set (high speed) is the absence of a wave at a design as a typical speed In addition, the waves (waves Xs having a small wave height to waves X _L having a large wave height) are traveled over the upper surface 21a of the lower valve 21 when traveling at nautical speed.

In FIG. 1, a broken line 210 virtually shows the shape of a conventional bow valve (one stage). As explained earlier, when the ship speed and wave height change when running in a ballast state, the way the wave is applied to the bow valve changes, the higher the ship speed and the higher the wave height, the higher the bow valve. It becomes easy to get a wave. However, the shape of the conventional bow valves, since the upper surface of the bow valve is in a high position, when even if the wave height is greater wave X _L occurs, a ship is running at low to medium speed, the wave bow Can't get over the valve. Further, even when the ship is traveling at a high speed (cruise speed), if the state in which the wave height is slightly larger wave X _M or height is smaller waves X _S occurs, the wave can not get over the bow valves .
In contrast, in the present embodiment, since the form bow valve 20 to the upper and lower stages in view of the ballast condition, the static water level raised position A _S and wave as described above, the wave height is greater wave X _L in state but occurring, ship fast big waves X _L when running at (cruise speed) can overcome the upper surface 22a of the upper valve 22 (FIG. 2 (a)), running at ship low to medium speed wave _{X L} height is large when the can overcome the upper surface 21a of the lower valve 21 (FIG. 2 (b), (c) ). Further, when the ship travels at a high speed (navigation speed) in a state where the wave X _M having a slightly large wave height is generated, the slightly large wave X _M can get over the upper surface 21a of the lower valve 21 (FIG. 2D). ), the ship is slightly larger waves _{X M} also when running at low to medium speed can get over the top surface 21a of the lower valve 21 (FIG. 2 (e), (f)). In a state where the wave height is smaller waves X _S occurs, but can not get over the top surface 21a of the lower valve 21 is height smaller waves X _S when the ship is running at a low to medium speed (FIG. 2 (h) , (i)), the ship is fast (may be overcome upper surface 21a of the lower valve 21 be a height smaller waves _{X S} when running at cruise speed) (FIG. 2 (g)).
Note that the wave height is greater wave-small waves, as shown in FIG. 3, when the height of the lower valve 21 and hB, a generally when wave height is greater than hB / 2 "height larger waves X _L", the case low is referred to as "wave X _S wave height is small." In addition, as “wave X _M having a slightly high wave height”, a wave height that is intermediate between “wave X _L having a large wave height” and “wave X _S having a small wave height” may be a wave around hB / 2.
Further, in a state where even greater than the wave height of the big waves X _L "very big waves" occurs, the wave even when the low speed to medium speed is sometimes overcome top 22a of the upper valve 22.
Thus, when traveling in a ballast condition, can even waves according to the bow valve 20 is smaller waves the lower valve 21 (the wave height is less X _S) is overcome when the cruise speed (high speed), and If the wave applied to the bow valve 20 is large even at low to medium speeds, the wave (wave X _L having a large wave height, wave X _M having a slightly high wave height) can get over the lower valve 21. Therefore, a small wave X _S , a wave X _L having a large wave height, and a wave having a large wave height at low to medium speeds are factors that increase resistance in waves during traveling at high velocities in the ballast state. against X _L, since waves can get over the top surface 21a of the lower valve 21, as shown in FIG. 4, not only when traveling at cruise speed (high speed), when traveling at low to medium speed As compared with the conventional bow valve, the increase in resistance in waves can be reduced.

Moreover, in this embodiment, the inflection part 30 of the front-end | tip upper part of the lower stage valve | bulb 21 of the stem line 11 is formed so that it may be located above the still water surface position B at the time of a stillness in the ballast state of a ship. . By forming in this way, it is possible to reliably obtain the effect of reducing the increase in resistance due to the waves getting over the bow valve 20 during traveling in the waves in the ballast state.
Further, since the bow valve 20 is formed in two upper and lower stages so as to cut off a part of the tip side of the conventional bow valve, the captain does not change compared to the case where the conventional bow valve is applied to a ship.

Furthermore, in the present embodiment, when the upper surface 22a of the upper valve 22 travels in a full load state of the ship, the rising position of the water surface that occurs when traveling in plain water that is in a state where there is no wave at nautical speed (high speed). are formed to be located below the full load condition, the static water level raised position a _L is. Loaded condition - than the static water level raised position A _L by forming the upper surface 22a of the upper valve 22 so as to be positioned downward, when running at full load condition, reliably wave drag reduction effect by the bow valve 20 Can be obtained.

  5A and 5B are diagrams showing a bow shape of an increase in resistance to waves according to another embodiment of the present invention. FIG. 5A is a side view and FIG. 5B is a front view. In addition, the same code | symbol is attached | subjected to the same functional member as the said embodiment, and description is abbreviate | omitted.

In this embodiment, the lower valve 21 protrudes forward from the upper valve 22 to form the stem line 11 of the bow valve 20 in two upper and lower stages, and the upper end of the upper valve 22 protrudes forward. Note that the upper end portion of the upper valve 22 that protrudes does not protrude forward from the front end of the lower valve 21.
In this way, by partially re-projecting the upper valve 22 forward, the upper surface 22a where the wave of the upper valve 22 rides can be widened, so that the upper valve 22 can be used during cruising speed in a ballast state. in the state where the wave height is greater wave X _L is generated to overcome, it is possible to increase the waves resistance reducing effect by the bow valve 20. Further, the effect of reducing the wave resistance by the bow valve 20 can be maintained at the same level as that of the conventional bow valve during traveling in a full state.

  FIG. 6 is a side view showing a bow shape in which the increase in resistance to waves is reduced according to still another embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the same functional member as the said embodiment, and description is abbreviate | omitted.

In the present embodiment, a gooseneck shape is formed in which the upper surface 21 a of the lower valve 21 once rises from the upper end of the tip toward the rear and then descends and rises again to connect to the upper valve 22. That is, the upper surface 21a of the lower valve 21 is raised at the front end side and settled at the rear end side.
By forming in this way, the upper surface 21a of the lower valve 21 that is the wave ride-up portion can be made wider, in other words, the area on which the wave rides can be increased.

  FIGS. 7A and 7B are diagrams showing a bow shape of an increase in resistance to waves according to still another embodiment of the present invention. FIG. 7A is a side view, FIG. 7B is a front view, and FIG. FIG. In addition, the same code | symbol is attached | subjected to the same functional member as the said embodiment, and description is abbreviate | omitted.

As shown in FIG. 7, the bow shape in which the increase in resistance to waves in this embodiment is reduced is a bow shape having a bow valve 120 on the bow portion 10 of the ship.
The frame line 111 of the bow valve 120 is formed in two upper and lower stages, and the lower valve 121 protrudes in the width direction from the upper valve 122, and the upper surface 121a of the lower valve 121 is more representative ballast condition, the static water level raised position a _S voyage speed which is set at design time (high speed) is a water surface raised position which occurs when traveling flat water present in the absence of the wave as the speed of each Further, the waves (waves Xs having a small wave height to waves X _L having a large wave height) are traveled over the upper surface 121a of the lower valve 121 when traveling at a voyage speed.

7 (b) and 7 (c), a broken line 210 virtually shows the shape of the conventional bow valve (one stage).
During running of the ballast condition, in the shape of a conventional bow valve shown by the dashed line 210, since the upper surface of the bow valve is in a high position, even if the wave height is greater wave X _L occurs, ship low to When driving at medium speed, waves cannot get over the bow valve. Further, even when the ship is traveling at a high speed (cruise speed), if the state in which the wave height is slightly larger wave X _M or less wave X _S occurs, the wave can not get over the bow valves.
In contrast, in the present embodiment, since the form bow valve 120 in upper and lower stages in view of the ballast condition, the static water level raised position A _S and wave as described above, to FIGS. 1 to 4 a stem line 11 of bow valve 20 described with reference as if formed on the upper and lower stages, in a state where the wave height wave height big waves X _L occurs, when the ship travels at a high speed (cruise speed) wave height the large wave X _L can overcome the upper surface 122a of the upper valve 122, the upper surface 121a waves X _L height is large when the ship is running at a low to medium speed is riding portion of the wave which is formed in the lower valve 121 (Figure 7 (c) hatched portion) can be overcome. In addition, when the ship is traveling at a high speed (navigation speed) in a state where the wave X _M having a slightly large wave height is generated, the slightly large wave X _M can get over the upper surface 121a of the lower valve 121, and the ship is low to medium. slightly larger waves X _M also when traveling at speed can get over the top surface 121a of the lower valve 121. In a state where the wave height is smaller waves X _S occurs, but can not get over the top surface 121a of the lower valve 121 is height smaller waves X _S when the ship is running at a low to medium speed, the ship is fast (voyage when traveling at speed) can overcome the upper surface 121a of the lower valve 121 even height is smaller waves X _S.
In the state in which the wave height may exceed "very big waves" the height of big waves X _L occurs, the wave even when the low speed to medium speed is sometimes overcome top 122a of the upper valve 122.
Thus, when traveling in a ballast condition, can wave a lower valve 121 even when the waves according to the bow valve 120 is small (the wave height is less X _S) is overcome when the cruise speed (high speed), and If the wave applied to the bow valve 120 is large even at low to medium speed, the wave (wave X _L having a large wave height, wave X _M having a slightly high wave height) can get over the lower valve 121. Therefore, the wave X _S having a small wave height, the wave X _L having a large wave height, and the wave height at a low to medium speed force are factors that cause a large increase in resistance in waves during traveling at high velocities. for large waves X _L, since waves can get over the top surface 121a of the lower valve 121, not only when traveling at cruise speed (high speed), conventional bow bulb even when running at low to medium speed Compared with, the increase in resistance in waves can be reduced.
Moreover, since the upper valve | bulb 122 can be formed in a triangle shape, the resistance received from a wave can be reduced further.

Further, in the present embodiment, the inflection portions 130 at the upper ends on both sides of the lower valve 121 of the frame line 111 are formed so as to be positioned above the still water surface position B when the ship is in a ballast state. ing. By forming in this way, it is possible to reliably obtain the effect of reducing the resistance in waves by traveling over the bow valve 120 during traveling in the waves in a ballast state.
Further, since the bow valve 120 is formed in two upper and lower stages so as to cut off a part of the side end side of the conventional bow valve, the width of the ship does not change compared to the case where the conventional bow valve is applied to a ship. .

Furthermore, in the present embodiment, the upper surface 122a of the upper valve 122 is at a raised position on the water surface that occurs when traveling in plain water that is in a state of no waves at sea speed (high speed) during traveling in a full state of the ship. It is formed so as to be positioned lower than a certain loaded condition, the static water level raised position a _L. Than full load condition, the static water level raised position A _L by forming the upper surface 122a of the upper valve 122 so as to be positioned downward, when running at full load condition, reliably wave drag reduction effect by the bow valves 120 Can be obtained.

  FIGS. 8A and 8B are diagrams showing a bow shape of a wave resistance increase / reduction according to still another embodiment of the present invention. FIG. 8A is a top view and FIG. 8B is a front view. In addition, the same code | symbol is attached | subjected to the same functional member as the said embodiment, and description is abbreviate | omitted.

  In the present embodiment, the upper angle is set to be larger than the lower angle as the angle formed by the tangent line when the lower valve 121 is viewed in plan. By setting in this way, it is possible to widen the upper surface 121a of the lower valve 121, where the wave rides, and to further reduce the increase in resistance in waves when traveling at low to medium speed.

  FIGS. 9A and 9B are diagrams showing a bow shape of a wave resistance increase / reduction according to still another embodiment of the present invention. FIG. 9A is a top view and FIG. 9B is a front view. In addition, the same code | symbol is attached | subjected to the same functional member as the said embodiment, and description is abbreviate | omitted.

In the present embodiment, the lower valve 121 is projected in the width direction from the upper valve 122 to form the frame line 111 of the bow valve 120 in two upper and lower stages, and the upper side end of the upper valve 122 is projected in the width direction. Thus, the frame line 111 is formed in two upper and lower stages. Note that the portion of the upper side end of the upper valve 122 that protrudes does not protrude outward from the side end of the lower valve 121.
Thus, by partially extending the upper valve 122 in the width direction, it is possible to widen the upper surface 122a where the wave of the upper valve 122 rides, and the wave X having a large wave height over the upper valve 122 is large. _In the state where _L occurs, the effect of reducing resistance in waves by the bow valve 120 can be enhanced. In addition, the effect of reducing the wave resistance by the bow valve 120 can be maintained at the same level as that of the conventional bow valve when traveling in a full state.
Moreover, since the upper valve | bulb 122 can be formed in a triangle shape, the resistance received from a wave can be reduced further.

  FIGS. 10A and 10B are diagrams showing a bow shape in which the increase in resistance to waves is reduced according to still another embodiment of the present invention. FIG. 10A is a side view, FIG. 10B is a front view, and FIG. FIG. In addition, the same code | symbol is attached | subjected to the same functional member as the said embodiment, and description is abbreviate | omitted.

In this embodiment, the bow valve 120 has a frame line 111 formed in two upper and lower stages, and the lower valve 121 protrudes in the width direction from the upper valve 122, and the upper surface 121a of the lower valve 121 is in a ballast state of the ship. The ballast state and static water level that is the rising position of the water surface that occurs when traveling in plain water where there is no wave at the sailing speed (high speed) set at the time of design as a typical speed for each ship upwardly than the raised position a _S, and wave (wave X _L wave Xs~ crest height is small is _large) are formed such that the position to overcome a top 121a of the lower valve 121 when running at cruise speed, Further, a protrusion 40 that induces wave formation is formed near the lower surface of the upper surface 121 a of the lower valve 121.
When the projection 40 is not present, the ballast state / static water level rising position is _AS , but by forming the projection 40 on the bow valve 120, a wave applied to the bow valve 120 is induced and becomes large, and the ballast state / static The target water level rise position is _ASL . Therefore, even when the boat speed is medium or low, it is easy for waves to get over the bow valve 120, and the effect of reducing the increase in wave resistance can be increased.
In addition, as shown in FIG. 10A, the protrusion 40 is preferably formed on the bow valve 120 so as to be lowered forward. By forming in this way, waves are easily induced.

  Further, the protrusion 40 is configured to be housed and extended in the width direction of the ship. With this configuration, the protrusions 40 can be overhanged and stored as necessary. Therefore, when the protrusion 40 is below the water surface, such as when it is fully loaded, it can be stored, and the increase in frictional resistance due to the protrusion 40 can be reduced.

  FIG. 11 is a front view showing a bow shape in which the increase in resistance to waves is reduced according to still another embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the same functional member as the said embodiment, and description is abbreviate | omitted.

In the present embodiment, a gooseneck shape is formed in which the upper surface 121a of the lower valve 121 once rises from the upper end of the tip toward the rear and then descends and rises again to be connected to the upper valve 122. In other words, the upper surface 121a of the lower valve 121 is raised at the front end side and settled at the rear end side.
By forming in this way, the upper surface 121a of the lower valve 121, which is the wave climbing portion, can be made wider, in other words, the area on which the wave rides can be increased.

  It should be noted that the wave resistance increase / reduction bow shape according to the present invention described in each of the above embodiments can be employed in a ship. Therefore, it is possible to reduce an increase in marine resistance of the ship during traveling in the ballast state.

  Further, the bow shape of the wave resistance increase / reduction head according to the present invention can be adopted for a large ship. Therefore, in the enlargement ship, it is possible to reduce an increase in resistance in waves during traveling in a ballast state.

  In addition, you can set the speed of the ship's speed setting means to reduce the increase in resistance in waves, including the speed of navigation, such as marking the speed setting device of the ship's engine or setting the speed stepwise. In such a case, the speed of the ship can be easily set so that the waves are positioned over the upper surface 21a (121a) of the lower valve 21 (121). Therefore, it is possible to reliably obtain the effect of reducing the increase in wave resistance by the bow valve 20 (120).

  ADVANTAGE OF THE INVENTION According to this invention, even if a ship is a ballast state, the ship which has the ship shape which can reduce the increase in resistance in waves, and the bow shape which increased resistance in waves, and the bow shape which increased resistance in waves can be provided.

10 bow 11 the stem line 20, 120 bow valve 21, 121 lower valve 22, 122 upper valve 30,130 inflection portion 111 frame line A _L full state-static water level raised position A _S ballast condition, the static water level raised position B still water position C load line X _L wave (wave height is large waves)
X _S waves (wave height is small)

Claims (16)

  A bow shape having a bow valve at the bow of the ship, the stem line of the bow valve is formed in two upper and lower stages, the lower valve protrudes forward from the upper valve, and the upper surface of the lower valve is When running in the ballast state of a ship, the ballast state / static state is the rising position of the water surface that occurs when traveling in flat water where there is no wave at the nautical speed set at the time of design as a typical speed for each ship. A bow shape for reducing the increase in resistance in waves, characterized in that it is formed so that the waves are positioned above the upper surface of the lower valve when traveling at the voyage speed and above the target water level rising position.   2. The inflection portion at the upper end of the lower valve of the stem line is formed so as to be positioned above a stationary water surface position when the ship is stationary in a ballast state. A bow shape that reduces resistance in waves.   3. The wave according to claim 2, wherein the upper surface of the lower valve has a gooseneck shape that once rises from the upper end of the tip toward the rear and then descends and rises again to connect to the upper valve. A bow shape that reduces medium resistance.   From the full load state / static water level rising position, which is the rising position of the water surface that occurs when traveling in the flat water where there is no wave at the voyage speed when the upper surface of the upper valve is traveling in the full load state of the ship 4. The wave-shaped resistance increase reducing bow shape according to claim 1, wherein the bow shape is formed so as to be positioned below.   5. The bow-shaped resistance-reducing bow shape according to claim 1, wherein the upper valve is partially re-projected forward. 6.   A bow shape having a bow valve at the bow portion of the ship, wherein the bow valve frame line is formed in two upper and lower stages, the lower valve protrudes in the width direction from the upper valve, and the upper surface of the lower valve is The ballast state that is the rising position of the water surface that occurs when the ship travels in plain water where there is no wave at the nautical speed set at the time of design as a typical speed for each ship when traveling in the ballast state -A bow shape with reduced resistance increase in waves, characterized in that the waves are positioned above the static water level rising position and when traveling at the nautical speed, so that the waves are positioned over the upper surface of the lower valve.   The inflection site | part of the both-sides upper end part of the said lower stage valve | bulb of the said frame line was formed so that it might be located above the still water surface position at the time of the said ballast state of the ship at the time of stillness. Increased resistance in the waves to reduce the bow shape.   8. The wave according to claim 7, wherein the upper surface of the lower valve has a gooseneck shape that once rises from the upper end of the tip toward the rear and then descends and rises again to connect to the upper valve. Increased resistance reduction bow shape.   From the full load state / static water level rising position, which is the rising position of the water surface that occurs when traveling in the flat water where there is no wave at the voyage speed when the upper surface of the upper valve is traveling in the full load state of the ship 9. The wave-shaped resistance increase reducing bow shape according to claim 6, wherein the bow shape is formed so as to be positioned below.   10. The wave according to claim 6, wherein an upper angle is set larger than a lower angle as an angle formed by a tangent line when the lower valve is viewed in plan. 10. Increased resistance reduction bow shape.   11. The bow-shaped resistance-increasing bow shape according to claim 6, wherein the upper valve is partially re-extended in the width direction.   The bow shape according to any one of claims 6 to 11, wherein a projection for inducing wave formation is formed on the bow valve.   The bow shape of the wave resistance increase-reducing head according to claim 12, wherein the projection is configured to be housed and extended in a width direction of the ship.   A ship having a bow shape with an increased resistance to wave resistance, wherein the bow shape with an increased resistance to wave resistance according to any one of claims 1 to 13 is adopted.   15. A ship having a bow shape with increased resistance in waves according to claim 14, wherein the ship is an enlarged ship.   16. The increase in wave resistance increase according to claim 14 or 15, wherein the speed setting means of the ship is configured to be able to set a speed corresponding to the increase in wave resistance including the voyage speed. A ship with a bow shape.