RU2535346C1 - Method to break ice cover and semi-submersible icebreaker ship - Google Patents

Abstract

FIELD: transportation.

SUBSTANCE: method is proposed to break ice cover, in which a pushing buoyant force is developed during motion of a semi-submersible ship, which presses at the lower surface of ice in vertical direction, and ice is broken with a ram brought under it with an ice-breaking rib connected to the ship body. The vertical pushing force is developed by all positive buoyancy of the semi-submersible ship and lifting force of its horizontal hydrodynamic rudders, at the same time the ram acts at ice in horizontal direction both by its inclined breaking rib and its entire surface. Also a semi-submersible icebreaking ship is proposed.

EFFECT: increased efficiency of ice cover breaking and icebreaking capability for transportation of loads.

8 cl, 9 dwg

Description

The invention relates to a method for breaking the ice sheet by sea icebreaking vessels for transporting goods - liquid (oil products, liquefied gas), bulk and containers, based on the use of Archimedean force and lift on horizontal rudders. The invention also relates to shipbuilding and can be used to create large-tonnage vessels year-round (including ice) all-weather navigation.

There are many different methods and devices for destroying the ice cover: from explosions on the surface of the ice or under it, melting ice with hot steam, electric heating, a laser beam, cutting ice with cutters, etc. However, all of them are feasible in thick ice only when the ship stops or at a low speed of the ship 2-3 knots.

A known method of destroying the ice cover [1] by increasing the buoyancy force exerting pressure on the ice with an ice-breaking ice-breaking device. However, this method does not allow to destroy ice with a thickness of 2-3 meters.

A known method of destroying the ice cover [2] by crushing ice with the cutting surface of the cutters located on the mast connecting the underwater and surface parts of the vessel. With this method, movement in ice with a thickness of 2-3 meters is possible only with an insignificant speed and at high energy costs.

The closest is the method of destruction of the ice cover [3] by creating a buoyant Archimedean force that presses the ice from the bottom upward with a cutting edge ramming under the ice, but since the buoyant Archimedean force is created only by a small volume of the submersible raft (since the raft itself is transported on a ship), the destructive forces cannot be significant. In addition, with this method, the destruction of ice is possible only when the ship stops.

In the device part, a semi-submersible icebreaking vessel [4] is known, consisting of an underwater cargo hull with engines and propulsors and a surface part with a superstructure, the underwater hull containing an ice-breaking device and ballast chambers. The disadvantage of this device is the inability to function in thick ice.

A semi-submersible icebreaking vessel [5] is known, consisting of an underwater cargo hull with engines and propulsors connected to an ice-breaking device and a surface part with a superstructure. The disadvantage of this device is that the destruction of ice occurs on the principle of an icebreaker, i.e. part of the hull runs into ice, which under the weight of the bow is destroyed, while only part of the mass of the vessel is used.

Known submarine ice swimming [6], including a wedge-shaped body having a profiled cone-shaped bow designed to break the ice. The disadvantage of this device is that this technical solution produces the destruction of ice only by the bow and does not provide an energy advantage in comparison with classical icebreaking vessels [7].

The closest is a semi-submersible icebreaking vessel [8], consisting of an underwater cargo hull with engines and propulsors, connected to an ice-breaking device and a surface part with a superstructure, the underwater hull containing ballast chambers. The disadvantage of this device is that the ice-breaking device is made in the form of mills, because of which such a vessel will have an insignificant speed of movement in ice with a thickness of 2-3 m with a large energy consumption for crushing ice. In addition, the narrow aisle remains behind the vessel, which is why there is a high probability of ice rubbing it, and the vessel does not have the opportunity to free itself, because it does not have the ability to turn 180 °, and when it moves, the swivel superstructure will experience large overloads on the swivel mechanism.

The present invention is directed to solving the problem of destroying ice fields with a thickness of 3 m or more with the lowest energy costs (reducing engine power consumption and increasing efficiency) and creating a large-tonnage vessel capable of transporting goods in thick ice conditions, moving independently with high cruising speed with good seaworthiness of the vessel in open water, and capable of navigating other surface ships without an icebreaker under comfortable conditions for the crew and passengers.

The main technical result achieved during the implementation of the claimed invention consists in a multiple reduction of the screw stop necessary for breaking the ice, increasing the average speed of the vessel, reducing the engine power available to the vessel and increasing its ice permeability at low energy costs (increasing efficiency) while ensuring comfortable crew conditions (vibration and shock inherent in the icebreaker fleet are excluded).

When using the same engine power, the claimed technical solution allows to increase throughput in ice and increase the ability to overcome thicker ice.

The problem is solved as follows.

In terms of the method, the ice cover is destroyed by creating a buoyant archimedean force that presses the bottom surface of the ice in a vertical direction by ramming an ice with an ice-breaking rib connected to the ship’s hull, according to the invention, the ram acts on the ice in the horizontal direction with its ice-breaking rib, and its entire surface, and the vertical buoyancy is created by the entire positive buoyancy of the semi-submersible vessel and the lifting force of the horizontal hydrodynamics iCal rudders and ram fracture occurs throughout its length, the vessel is formed of a moving lane width sufficient for the passage of surface vessels.

Moreover, to destroy ice, the vessel makes vertical wave-like movements along the way, which increases the efficiency of ice destruction and saves energy spent.

Moreover, to destroy ice, the vessel moves along the course at any angle, up to 180 °, which makes it possible to rescue the vessels following the ice and bypass impassable hummocks.

Moreover, when reversing, the ice collapses in the stern of the ram, which increases the maneuverability of the vessel.

In the device part, a semi-submersible icebreaking vessel with bow and stern parts is declared, consisting of an underwater cargo hull with engines, propulsors and horizontal hydrodynamic rudders connected to an ice-breaking device and a surface part with a superstructure, the underwater hull containing ballast chambers, according to the invention, the ice-breaking device is a ram with a sharp inclined destructive rib, starting from the bow of the vessel and located along its entire hull.

Moreover, the ice-destroying rib of the ram is located at an angle of 3 ° to 7 ° to the longitudinal axis of the hull, which reduces the ice load on the ram and allows the ice to be destroyed with minimal energy.

Moreover, the surface part with the superstructure is located at the stern of the vessel, which allows to increase the length of the front part of the ram, which saves energy on the destruction of ice.

Moreover, ballast chambers are located in the bow and stern of the vessel, which allows to increase and adjust its trim and stability. This arrangement of ballast chambers allows you to affect the thickness of the ice along the entire length of the vessel, which reduces energy costs.

Moreover, the tilt angle of the ice-breaking ram of the ram located in the stern of the vessel is from 3 ° to 7 °, which increases the maneuverability of the vessel.

Moreover, horizontal hydrodynamic rudders have a large surface, which allows to increase vertical lifting force at low energy costs.

The invention is illustrated by drawings:

Figure 1 - semi-submersible icebreaking vessel (side view);

Figure 2 - semi-submersible icebreaking vessel (top view);

Figure 3 - semi-submersible icebreaking vessel (view in front);

Figure 4 - semi-submersible icebreaking vessel, a perspective view;

Figure 5 shows a parallelogram of the forces applied to the ram during passage of the ice cover, while the letter U indicates the stop of the screws, and the letter P destructs the ice force;

6 is a view of an experimental setup;

7 is an experimental study using the proposed technical solution;

Fig - experimental study using the classic icebreaking scheme;

Fig.9 is a comparative table of the dependence of ice resistance on the thickness of the ice for the icebreaker and the proposed method.

The semi-submersible icebreaking vessel (Fig. 1 - Fig. 4) consists of an underwater cargo hull 1, on the upper outer surface of which, starting from the bow, along the entire hull of the vessel, a special strong ram is longitudinally formed, which is a single unit with the ship's hull, consisting of a bow part 2 and aft part 3, in the housing 1 there are engines and propulsors, including those ending with shunting screws 4, in the bow and aft parts of the housing 1 there are axisymmetrically located ballast chambers 5, a horizontal is installed along the housing s hydrodynamic handlebars 6, the stern hull is narrow above-water superstructure 7 15-20 m tall, ending at the top chassis wheelhouse 8 with a helipad, ledorazruschayuschee ram has an acute inclined edge 9, starting from the bow of the vessel and extending along its entire body. In this case, the ice-breaking rib 9 is located at an angle from 1: 8 to 1:15 (from 3 ° to 7 °) to the longitudinal axis of the hull 1 of the vessel. To reduce ice resistance during movement, the hull 1 of the vessel is located under the ice. On the surface is only part of the ram and the superstructure 7 with the wheelhouse 8.

The method consists in the fact that the destruction of ice occurs when the vessel is moving with a special strong ram located on top of the hull along its entire length. Structurally, the ram is a narrow, no more than 3 m, and high, at least 15 m, fin with an inclined ice-breaking rib. When the destruction of ice by the claimed method, the hull is deepened to a depth of not less than 10 m and has a conventional, not reinforced structure.

The implementation of the method and the operation of the device is as follows. In the process of moving the hull of the vessel 1 is under water. When the vessel moves, the bow of the battering ram 2 comes under the ice, raises and destroys it with a sharp edge 9, while behind the vessel, wormwood is formed, sufficient for the passage of other vessels. When the ship moves in reverse, the ice is destroyed by the stern of 3 rams.

The vertical destructive force P (Fig. 5) is created by the positive buoyancy of the vessel and the horizontal hydrodynamic rudders-wings 6. Archimedean lifting force is provided by four ballast chambers 5 located in the bow and stern parts (Fig. 3). They carry out longitudinal and transverse stability. For example, the vertical lift force produced by the horizontal hydrodynamic control surfaces at their area of 2500 m ² and the speed of the vessel 20 km / h can be about 9 tons, and the positive buoyancy when displacement 200 tons vessel (by taking 10% of the displacement of the vessel) would create vertical the destructive force of 20 thousand tons (displacement of modern icebreakers), and in total (Archimedean force plus the force of the rudders) will be almost equal to the displacement of the designed modern icebreakers (33 thousand tons) (10), and with an increase in tonnage trolled ship - and even more. In especially powerful ice, the movement becomes undulating, i.e. the vessel reduces buoyancy and hull 1 with a ram, with small screw stops, enters two-thirds of its length under ice. Positive buoyancy increases to the limit, destroying the ice with a rib of a ram when it emerges, then the destruction cycle is repeated. At the same time, the vessel does not back up, which increases cruising speed. Wave motion can also be carried out by changing the vertical force on the horizontal rudder-wings of a large area.

An example of a specific application. Comparative experimental studies have shown the advantage of the proposed method of movement in heavy ice, in comparison with classical icebreakers. The experiments were carried out on models manufactured on a scale of 1: 100. The model of the prospective designed icebreaker [9], the pitch angle of which was 21 ° to the ice plane, and not 29 °, as with the existing icebreakers, was taken as the classical scheme. This form of the bow (as shown by experiments) allows one and a half times to reduce ice resistance. The width along the waterline is 0.33 m, which corresponds to 33 m for a natural icebreaker. The maximum height of a ram with an ice-breaking edge of a semi-submersible icebreaking vessel in the model version was 0.03 m (3 m from nature). The angle of inclination of the sharp rib of the ram to the longitudinal axis of the hull was 1:10 (5 °), which increased ten times the destructive force in comparison with the stop of the screws. Such an inclination angle of the ram with its length of 200 m makes it possible to have a surface height of 20 m, which allows the hull of the vessel to be deepened by 10 m or more and, accordingly, leads to a decrease in hydrodynamic wave resistance. Studies have shown a seven-fold decrease in the horizontal force of ice resistance during the implementation of the proposed method using the inventive vessel. The comparison was carried out according to the maximum amplitude values of the ice resistance (for the classical scheme). Moreover, when applying the proposed method provides a smooth process of destruction (in contrast to the classical scheme), the destructive load is almost constant. The width of the resulting wormwood in terms of nature was 30-40 meters. This allows the vessel to freely maneuver, turning 180 ° on the spot, and prevents the vessel from overwriting with ice, while at the same time the width of the wormwood allows for ordinary, non-icebreaking vessels. In addition, it was found that an increase in the angle of more than 1: 8 (7 °) to the longitudinal axis of the body with a fixed stop of the screws leads to a significant reduction in the destructive vertical force, and at angles less than 1:15 (3 °), the ram height with an edge it becomes insufficient even if the vessel is longer than 200 m (in terms of nature). With insufficient height of the ram with the rib during the movement of the vessel, the ice plates abut the superstructure 7 and create additional resistance, therefore, the smallest angle should provide a smooth flow around the destroyed part of the ice in the icy part of the ram without touching the superstructure 7.

The experimental setup (Fig.6) consists of a guide along which a special carriage runs. The carriage is driven by an electric winch. The model under study is attached to the carriage and a force measuring device is located on it, which measures the horizontal breaking force of the models. All experiments were carried out on models manufactured on a scale of 1: 100 in full-scale winter conditions. The studies were carried out as follows. First, a ram model of the proposed design (Fig. 7) was run at a length of 4 meters, and then a classic icebreaker model (Fig. 8) was run at the same length. This ensured equality of conditions for comparative tests. The research results are shown in the table (Fig.9).

The novelty and advantage of the claimed technical solution in terms of the method also consists in the fact that with the horizontal movement of the vessel due to the destructive force created by the sharp edge of the ram, lifting the ice from bottom to top, wormwood is created, comparable to the width of the vessel (confirmed experimentally), which allows formed wormwood other vessels. Moreover, this requires 7-10 times less effort from the power plants of the vessel compared to the classical scheme, in addition, with an increase in the displacement of the vessel, the efficiency of icebreaking properties increases with the same power of the power plant. The proposed method allows you to combine the seaworthiness of the vessel in clean water with good icebreaking. In addition, due to the smooth movement during the destruction of ice, the crew of the vessel is in comfortable conditions compared to the icebreaker. This allows the vessel to cross any Arctic ice at an acceptable commercial speed. A semi-submerged driving mode in clean water is also beneficial, as significantly reduces hydrodynamic wave resistance and reduces shock waves during storms.

Thus, the combination of known and new features of the proposed technical solution allows to obtain such technical results as increasing the efficiency of the vessel in ice fields with a thickness of 3 m or more, namely increasing the average speed, reducing the engine power available to the vessel, and increasing it ice penetration at low energy costs (increased efficiency) while ensuring comfortable crew conditions, and at the same time allows creating wormwood sufficient to provide during passage of other vessels.

Literature:

1. USSR copyright certificate No. 1758976. A device for breaking ice.

2. US patent No. 3868920. Semi-submerged cargo transport system.

3. RF patent No. 2360825. The device for the destruction of the ice cover.

4. Application of the Netherlands NL 2011/050494. Semi-submersible vessel and operating method.

5. RF patent No. 2389640. Arctic ice-breaking transport large-capacity vessel with an ice-resistant pylon.

6. RF patent No. 95101443.

7. Icebreakers. IN AND. Kashtelyan et al. Shipbuilding, 1972

8. US patent No. 4350114. Semi-submersible tanker with directional ice cutters.

9. L.G. Sing it. Two-draft icebreaker for the Arctic // Atomic Strategy XXI, 2008, No. 36, p. 20.

Claims (8)

1. A method of destroying ice cover, in which, when a semi-submersible vessel is moving, a buoyant Archimedean force is generated that presses on the bottom surface of the ice in the vertical direction, and ice is destroyed by a ramming beneath it with an ice-breaking rib connected with the hull of the ship, characterized in that the vertical buoyancy force create all the positive buoyancy of a semi-submersible vessel and the lifting force of its horizontal hydrodynamic rudders, while the ram acts on the ice in the horizontal direction as its with a pubic destructive rib and its entire surface. 2. The method according to claim 1, characterized in that the destruction of the ice cover is carried out when the semi-submersible vessel is reversed. 3. The method according to claim 1, characterized in that for the destruction of ice the vessel along the course makes vertical wave-like movements. 4. Semi-submersible icebreaking vessel with bow and stern, consisting of an underwater cargo hull with engines, propulsors, ballast chambers, horizontal hydrodynamic rudders and an ice-breaking device and a surface part with a superstructure, characterized in that the ice-breaking device is longitudinally formed on the outer upper surface of the cargo body the vessel, starting from the bow, along the entire hull and made in the form of a ram with an inclined ice-breaking rib. 5. Semi-submersible icebreaking vessel according to claim 4, characterized in that the angle of inclination of the ice-breaking rib of the ram is from 3 ° to 7 ° to the longitudinal axis of the hull. 6. Semi-submersible icebreaking vessel according to claim 4, characterized in that in the stern of the vessel, the angle of inclination of the ice-breaking rib of the ram is from 3 ° to 7 ° to the longitudinal axis of the hull. 7. Semi-submersible icebreaking vessel according to claim 4, characterized in that the surface part with the superstructure is located in the stern of the vessel. 8. Semi-submersible icebreaking vessel according to claim 4, characterized in that the ballast chambers are located in the fore and aft parts of the vessel.

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