JP7740684B2 - Workboat barge - Google Patents

Description

This invention relates to a barge for a work boat.

Conventionally, a work boat barge has been known to have a structure equipped with a tunnel that runs along the bottom of the vessel from bow to stern.

Technology has been proposed for such barges to reduce sailing resistance and further improve propulsion efficiency by efficiently forming an air layer between the ceiling surface of the concave water flow channel and the water (see, for example, Patent Document 1).

JP 2020-168988 A

However, with the above-mentioned conventional technology, the ceiling surface of the concave water flow groove is tapered, widening toward the front near the bow, and the left and right edges extend parallel from the base of the taper to the stern. As a result, as the length of the concave water flow groove increases, resistance increases, reducing propulsion efficiency.

This invention was made in consideration of the above-mentioned problems, and aims to provide a barge for a work vessel that further improves propulsion efficiency by forming the main body width of the concave water flow channel to taper toward the stern, efficiently forming an air layer between the ceiling surface and the water.

This invention relates to a workboat barge configured to be operated by attaching a push boat to the aft end of a non-self-propelled hull (operated by external power without a propulsion unit). The barge has a downward-opening concave water flow groove formed in the bottom from the aft end of the hull to the bow member, the front end of the concave water flow groove opens above the waterline, and the front end of the concave water flow groove is tapered so that it widens toward the front. From the base of the tapered groove, the left and right edges are tapered so that they widen toward the rear. The bow position of the bottom of the concave water flow groove rises at a steep angle, and the ceiling surface of the concave water flow groove aft of the raised bow rises at a steeper angle than the bottom, forming a slope that rises entirely from the aft end of the bow to the rear of the bottom. Furthermore, the sloped bottom surface of the concave water flow groove that rises to its end is positioned in the water below the waterline when in operation.

According to the invention of claim 1, a work boat barge is configured to be operated by attaching a push boat to the aft end of a non-self-propelled hull that is operated by external power without a propulsion unit. A downward-opening concave water flow groove is formed in the bottom of the hull from the aft end of the hull to the bow member. The front end of the concave water flow groove opens above the waterline and is tapered, widening toward the front. From the base of the taper, the left and right edges are tapered, widening toward the rear. The bow position of the bottom of the concave water flow groove rises at a steep angle, and the ceiling surface of the concave water flow groove aft of the raised bow rises at a steeper angle than the bottom, forming a slope that rises entirely from the aft end of the bow to the rear of the bottom. Furthermore, the sloped bottom surface of the concave water flow groove, which rises to its end, is positioned below the waterline during operation, resulting in the following effects.

In other words, when the barge is in operation, air can be efficiently taken in along with water from the opening at the front end of the concave water flow groove. The air bubbles that are taken in accelerate along the inclined surface of the concave water flow groove as they exit the rear end of the hull, allowing the accelerated water flow to be used to power the push barge's propulsion device. This reduces the barge's running resistance, requiring less power or allowing it to move at higher speeds, resulting in energy savings and increased speed.

In addition, the inclined bottom of the vessel is designed to be located below the waterline during operation, ensuring energy savings and increased speed even when the water surface is rough.

In particular, the front end of the concave water flow groove is tapered, diverging toward the front, and the left and right edges from the tapered base are tapered toward the rear. The bow portion of the bottom of the concave water flow groove rises at a steep angle, and the ceiling of the concave water flow groove behind the raised bow rises at a steeper angle than the bottom, forming a slope that rises all the way from the rear end of the bow to the rear of the bottom. This makes it possible to send the water flow taken in from the front end of the concave water flow groove to the power of the push barge's propulsion device without slowing it down, even if the distance from the rear end of the hull to the bow member is long. Moreover, because the main body of the concave water flow groove is diverged toward the stern, the water flow caused by propulsion sent to the power of the push barge's propulsion device spreads out in a diverging shape before flowing into the push barge's propulsion device. This, combined with the rearward diffusion of the water flow caused by the upward slope of the bottom of the concave water flow groove from the bow to the rear, assists the push barge's propulsion function. This will ensure that even large barges can achieve energy savings and higher speeds.

Furthermore, when stopping the hull, the pusher's propeller, a well-known technology, is rotated in the reverse direction to neutralize the previous propulsive force and stop the hull. When the propeller rotates in the reverse direction, the water flows toward the tip of the bottom of the hull, providing rearward thrust for the hull. However, the ceiling surface of the concave water flow channel behind the raised bow is angled at a steeper angle than the bottom, forming an entirely upward slope from the rear end of the bow to the rear of the bottom. As a result, the water flow from the reverse-rotating propeller hits the slope, slides smoothly along it, and flows toward the front end of the hull, providing rearward thrust for the hull.

Furthermore, because the concave water flow groove is configured with a tapered shape that widens all the way to the stern, the concave water flow groove quickly and reliably takes in the water flow from the counter-rotating propeller through the expanding part of the tapered shape, allowing the barge to generate rearward propulsion with little power. Furthermore, the water flow taken in by the concave water flow groove increases in flow speed as it passes through the gradually narrowing groove, thereby further strengthening the rearward propulsion force.

In this way, the barge of the present invention has a concave water flow channel with a tapered, diverging edge extending from the rear end of the bow to the rear of the bottom, and an inclined surface that rises all the way up, allowing the bottom stopping mechanism to function smoothly despite the small amount of power required.

FIG. 2 is a bottom view showing an example of the configuration of a barge according to an embodiment of the present invention. 2 is a cross-sectional view taken along line AA in FIG. 1. 2 is a cross-sectional view taken along line BB in FIG. 1. FIG. 10 is a plan view showing an example of the configuration of a barge in another embodiment.

The gist of this invention is to provide a workboat barge configured to be operated by attaching a push boat to the aft end of a non-self-propelled hull that is operated by external power without a propulsion unit. The barge has a downward-opening concave water flow groove formed in the bottom of the hull from the aft end of the hull to the bow member, the front end of the concave water flow groove opens above the waterline, and the front end of the concave water flow groove is tapered so that it widens toward the front, and from the base of the taper, the left and right edges are tapered so that they widen toward the rear. The bow position of the bottom of the concave water flow groove rises at a steep angle, and the ceiling surface of the concave water flow groove aft of the raised bow rises at a steeper angle than the bottom, forming a slope that rises all the way from the aft end of the bow to the rear of the bottom. Furthermore, the sloped bottom surface of the concave water flow groove that rises to its end is positioned in the water below the waterline when in operation.

An embodiment of the present invention will be described in detail with reference to the drawings. Figure 1 is a bottom view of a barge for a work vessel according to this embodiment. Figure 2 is a cross-sectional view taken along line A-A in Figure 1. Figure 3 is a cross-sectional view taken along line B-B in Figure 1.

The workboat barge 10 according to this embodiment is a non-self-propelled hull 20 that is operated by external force without a propulsion device, and is configured to operate by attaching a push boat T to the aft end 21. A downward-opening concave water flow groove 30 is formed in the bottom 23 from the aft end 21 of the hull 20 to the bow member 22. The front end 31 of the concave water flow groove 30 opens above the waterline WL, and the front end 31 of the concave water flow groove 30 is formed in a tapered shape that widens at the front end, and the tapered base 32 extends from the left and right edges The recessed water flow groove 30 is formed in a tapered shape that widens toward the rear, the bow 24 position of the ship's bottom 25 is raised at a steep angle, and the ceiling surface 33 of the recessed water flow groove 30 behind the raised bow 24 is raised at a steeper angle than the bottom, forming an inclined surface 34 that rises entirely from the rear end of the bow 24 to the rear of the ship's bottom 25, and the inclined surface 34 of the ship's bottom 25 of the recessed water flow groove 30 that rises to its end is configured to be located in the water below the waterline WL during operation.

As shown in Figures 1 and 2, the work barge 10 in this embodiment is a non-self-propelled type that does not have a propulsion device and is propelled by external power. Note that there are also self-propelled barges that have a propulsion device and are configured to move under their own power, and the present invention can also be applied to self-propelled barges.

Pushers T1 and T2 are installed at the rear end 21 of the hull 20, allowing it to be operated. In this embodiment, two pushers T1 and T2 are arranged side-by-side in parallel, but the number can be increased to three or more as long as it does not affect the navigation of the barge 10, or reduced to one, as in the hull 100 of another embodiment shown in Figure 4.

As shown in Figures 1 and 2, the barge 10 is provided with a concave water flow groove 30 that runs from the aft end 21 of the hull 20 to the bow member 22.

The front end 31 of the concave water flow groove 30 opens above the waterline WL and is tapered to widen toward the front. Furthermore, the concave water flow groove 30 is configured to rise at a steep angle at the bow 24 position of the ship's bottom 25.

From the tapered base 32 of the concave water flow groove 30, which widens toward the front, to the rear, the left and right edges of the concave water flow groove 30 are tapered and widened toward the rear. Furthermore, the bottom 25 of the concave water flow groove 30 rises at a steep angle from the base 32, forming an inclined surface 34 that rises all the way from the rear end of the bow 24 to the rear of the bottom 25.

Furthermore, the end of the concave water flow groove 30 that forms the rising inclined surface 34 is configured to be located in the water below the waterline WL when the barge 10 is in operation.

As shown in Figures 2 and 3, the barge 10 has a deck 26 on the top, with ship side members 27, 27 attached to both ends. The forward area of the deck 26 has a roughly arc-shaped planar shape, and a bow member 22 is attached to its front end.

Furthermore, a stern member 28 with a linear, planar shape is provided in the width direction at the rear end 21 of the deck 26.

As shown in Figure 2, the bottom 23 of the hull 20 of the barge 10 varies from front to back. The bottom material 25c extends from the stern material 28 to approximately 30% of the forward area of the hull 20, and the bottom material 25b extends from the front end of the bottom material 25c to approximately 30% of the forward area of the hull 20, forming a substantially horizontal bottom material. The bottom material 25a extends from the front end of the bottom material 25b to the front end of the hull 20, forming a curved upward curve. Furthermore, the tip 25d, which is the front end of the hull 20, rises vertically.

The bow member 22, deck 26, side members 27, 27, bottom members 25a, 25b, 25c, tip 25d, and bow member 22 are connected in a watertight manner. Furthermore, notched pusher recesses 29, 29 are provided in the deck 26 and stern member 28 at the stern, into which pusher boats T1, T2 are inserted so that they are parallel to the centerline connecting the bow member 22 and stern member 28 of the hull 20. As shown in Figure 2, the pusher recesses 29, 29 have open lower ends.

In addition, push boats T1 and T2 are configured so that a screw S, which generates propulsive force when rotated, is located at the lower rear.

As shown in Figures 1 to 3, the barge 10 is provided with a downward-opening concave water flow groove 30 that runs from the front of the pusher recesses 29, 29 to the bow member 22 area and along the bottom members 25a, 25b, and 25c.

The ceiling surface 33 of the concave water flow groove 30 changes heightwise as it faces the ship's bottom materials 25a, 25b, and 25c, and the front end 31 is tapered and flared toward the front. The concave water flow groove 30 is arranged symmetrically across the center line C, with the front end 31 opening above the waterline WL and rising at a steep angle at the bow 24.

In other words, the front end 31 of the concave water flow groove 30 opens into the air above the waterline WL, and forms a tapered front taper section 36 that widens toward the tip of the front end 31, which is in the direction of travel of the hull 20 of the barge 10.

Aft tapered section 37 extends from base 32, located aft of forward tapered section 36, to the aft end 21 of the hull 20. The ceiling surface 33 of the aft tapered section 37 rises at a steep angle, forming a sloped surface 34 that rises entirely from the aft end of bow 24 to the rear of bottom 25.

Specifically, a forward tapered section 36 that widens toward the front end extends from the forward end 31 of the concave water flow groove 30 to approximately 20% of the rear of the hull 20, and a rear tapered section 37 that widens toward the front extends from the base 32 of the forward tapered section 36 to the rear end of the concave water flow groove 30.

In particular, by forming the rear tapered section 37 so that it gradually widens from the base 32 of the front tapered section 36 and by making the entire surface an upwardly sloping surface, the resistance to sending the water and air taken in from the front tapered section 36 rearward is kept as low as possible, making it possible to send the water and air to the aft end 21 of the hull 20 without reducing their flow velocity.

This allows a powerful current of water to be sent to the propeller S of the push barge T installed at the rear end 21 of the hull 20, reducing the running resistance of the barge 10 and enabling it to travel at higher speeds or with less power, contributing to energy savings and increased speed.

When the hull 20 is stopped, the pusher T's screw S is rotated in the reverse direction, neutralizing the existing propulsive force and stopping the hull. When the screw S is rotated in the reverse direction, the water flows toward the tip of the bottom 23 of the vessel, providing a rearward propulsive force for the hull 20. However, the ceiling surface 33 of the concave water flow groove 30 behind the raised bow 24 is raised at a steeper angle than the bottom, forming an entirely upward inclined surface 34 from the rear end of the bow 24 to the rear of the bottom 25 of the vessel. As a result, the water flow from the reverse-rotating screw S hits the inclined surface 34, slides smoothly along it, and flows toward the front end of the hull 20, providing a rearward propulsive force to the hull 20.

Moreover, the concave water flow groove 30 is configured with a tapered shape that widens all the way to the stern, located at the rear end 21 of the hull 20. This allows the concave water flow groove 30 to reliably take in the water flow from the reverse-rotating screw S, enabling the barge 10 to generate rearward propulsion with little power. Furthermore, the water flow taken in by the concave water flow groove 30 increases in flow velocity as it passes through the gradually narrowing groove, thereby further strengthening the rearward propulsion force.

Therefore, by providing the barge 10 with the concave water flow groove 30 configured as described above, the left and right edges are formed into a tapered shape that widens from the rear end of the bow to the rear of the bottom of the vessel, and the entire surface is formed into an upward-sloping inclined surface, which, combined with the above, enables the vessel to stop smoothly even with a particularly small amount of power.

In the barge 10 configured as described above, two push boats T1 and T2 are fitted into the push boat recesses 29 and 29 of the barge 10, respectively. When the propellers S of the push boats T1 and T2 are driven to rotate by power, the barge 10 is propelled forward by the propulsion force. Note that the waterline WL shown in Figure 2 represents the waterline during operation.

When the barge 10 is in operation, wave resistance is generated on the barge 10, but the concave water flow grooves 30 reduce this resistance and improve the propulsion efficiency of the push boats T1 and T2. This allows the barge 10 to operate with reduced power output from the push boats T1 and T2 compared to when the barge 10 does not have the concave water flow grooves 30.

The front end 31 of the concave water flow groove 30 opens above the waterline WL, and is tapered to widen toward the front. The left and right edges extending from the tapered base 32 continue to taper to widen toward the rear. The bottom 25 of the concave water flow groove 30 rises at a steep angle toward the bow 24, and the ceiling 33 of the concave water flow groove 30 aft of the raised bow 24 rises at a steeper angle than the bottom, forming a sloped surface 34 that rises entirely from the aft end of the bow 24 to the rear of the bottom 25. Furthermore, the bottom sloped surface 34 of the concave water flow groove 30, which rises to its end, is positioned below the waterline WL during operation, resulting in the following effects.

In other words, when the barge 10 moves forward at a certain speed, the water flow and air hit the hull 20 relative to this forward movement and effectively flow in through the opening at the front end 31 of the concave water flow channel 30.

In addition, air flowing in from the front end 31 of the concave water flow groove 30 forms bubbles on the ceiling surface 33. As the bubbles flow from the front to the rear of the concave water flow groove 30, they are accelerated by the fully upward-sloping inclined surface 34 from the rear end of the bow 24 to the rear of the bottom 25, thereby reducing running resistance.

The forward end 31 of the downward-opening concave water flow groove 30 is located above the waterline WL on the bottom 23 of the ship, from the aft end 21 of the hull 20 to the bow member 22. This allows air to be effectively drawn in through this opening due to wind pressure while sailing, and is introduced into the ceiling surface 33 of the concave water flow groove 30, forming air bubbles, which reduce sailing resistance, save fuel, and increase ship speed.

Furthermore, as the air bubbles flow from the base 32 of the concave water flow groove 30 to the rear of the vessel bottom 25, the left and right edges of the concave water flow groove 30 are tapered and formed with an entirely upward-sloping inclined surface 34, which accelerates the air bubbles toward the rear and sends the accelerated water flow to the propeller S of the push barge T. This reduces the barge's running resistance and requires less power or allows for faster speeds, contributing to energy savings and increased speed.

As shown in Figures 1 and 2, tow boats T1 and T2 are stored and installed by fitting into tow boat recesses 29, 29 drilled to face the rear end 35 of the concave water flow channel 30. The tow boat recesses 29, 29 are drilled to penetrate from the deck 26 to the bottom 23 of the ship, and tow boats T1 and T2 are fitted into the tow boat recesses 29, 29 in a floating state.

The tow boats T1 and T2 have arc-shaped tips, and their entire widths abut linearly against the arc-shaped pushed portion 29a formed in the tow boat recess 29 on the hull 20 to correspond to this, and both sides of the tow boats T1 and T2 are sandwiched between the side walls 29b and 29b of the tow boat recess 29.

This allows the push boats T1 and T2 to generate forward hydraulic force while sandwiched between the side walls 29b, 29b of the push boat recess 29 without touching each other sideways. The tips of the push boats T1 and T2 contact the arc-shaped pushed portion 29a in a linear fashion over the entire length, allowing thrust to be transmitted smoothly to the hull 20 without being concentrated at a point. Furthermore, by varying the thrust of the push boats T1 and T2, the direction of the hull 20 can be changed.

10 Barge 20 Hull 21 Aft end 22 Bow member 23 Bottom 24 Bow portion 25 Bottom portion 26 Deck 27 Side member 28 Stern member 29 Push boat recess 30 Concave water flow groove 31 Forward end 32 Base 33 Ceiling surface 34 Inclined surface 35 Aft end 36 Forward tapered portion 37 Aft tapered portion T1, T2 Push boat WL Waterline S Screw

Claims (1)

A barge for a work boat configured to be operated by installing a push boat at the rear end of a non-self-propelled hull that is operated by external power without having a propulsion device,
A downwardly opening concave water flow groove is formed on the bottom of the hull from the rear end to the bow material,
The concave flow channel is
The front end of the hull is open above the waterline , and the front end is a tapered portion that tapers toward the front , and the rear end is a tapered portion that tapers toward the rear from the base of the taper of the front end to the left and right edges of the rear ,
A barge for a work vessel configured such that the length of the front tapered section in the longitudinal direction is shorter than the length of the rear tapered section in the longitudinal direction, while the taper angle of the rear tapered section is gentler than that of the front tapered section, so that the bow position of the bottom of the vessel of the concave water flow groove rises at a steep angle, and the ceiling surface of the concave water flow groove behind the raised bow rises at a steeper angle than the bottom, forming an inclined surface that rises all the way from the rear end of the bow to the rear of the bottom of the vessel, and further, the inclined surface of the vessel bottom of the concave water flow groove that rises to the end of the concave water flow groove is positioned in the water below the waterline during operation.