RU2217349C2 - Method of capsizing ship - Google Patents

Abstract

FIELD: emergency repair of ships below waterline; rescue of ships, cargo and crew; arresting aggressor- ship, neutralization of combat capabilities of enemy ship. SUBSTANCE: proposed method includes creating capsizing moment by displacement of water under section of ship's hull whose width extends from CL to WL of side through which ship is capsized and length of this section extends from bow to stern by foam fed from submarine continued till complete capsizing of ship with her keel up. Foam may be formed by foaming water fed from submarine by compressed gas. EFFECT: extended capabilities. 2 cl, 6 dwg

Description

 The proposed method can be used in the fleet for emergency repairs of the ship’s hull below the waterline, rescue of the crew, cargo and the ship that received the leak, detention of the intruder, neutralization of the enemy’s warship, while preserving the life of the crew members.

 To repair the hull of a vessel that has received a leak below the waterline, it is removed from the water by a crane, winches or a ship-lifting structure (see Big Soviet Encyclopedia, 3rd ed., 1973, v.25, p.52). However, such operations are carried out in ports having the necessary equipment. Untimely elimination of the leak leads to the loss of the vessel, cargo and the death of the crew.

 There is a known method of saving a vessel, which includes maintaining positive buoyancy after an accident, characterized in that they create a tipping moment and turn the vessel upside down with the keel, hold it in this position, and then transport it by the rescue vessel to the port (see the description of patent RU 2127691, B 63 C 7/00). The overturning moment turning the ship is proposed to create an engine of missiles mounted on one side. The disadvantage of this method is the absence of missiles on ships.

 Numerous cases are known of turning vessels upside down by keel due to side wind, side rolling, displacement of the center of gravity of the transported cargo, not symmetrical with respect to the diametrical plane, flooding of the compartments of the vessel, etc. The inverted vessel retains positive buoyancy for a certain time. The crew, cargo and the ship itself can be saved by turning the ship to its original position - keel down. The lack of a method of turning the vessel to its original position leads to the death of the crew, loss of cargo and vessel.

 The proposed method allows the vessel to turn over from the keel down to the keel up position or vice versa.

 The transverse stability of the vessel is much less than the longitudinal stability. The transverse stability of the vessel is ensured by the restoring moment that occurs when the vessel is tilted at a certain angle of heel under the influence of the overturning moment (see Big Soviet Encyclopedia, 3rd ed., 1973, v. 18, p. 584). The vessel can be turned over by creating conditions under the vessel in the aquatic environment for the appearance of a tipping moment exceeding the recovery moment in magnitude.

 The technical task of turning the vessel over is achieved by replacing the water with foam under the section of the vessel in width from the diametrical plane to the waterline of the side through which the turning is planned, and in length from the bow to the stern. Under the hull of the vessel, in the area from the diametrical plane to the waterline of the side through which they plan to turn over, the water is replaced with foam, whose density is less than the density of water. According to Archimedes' law, this reduces the buoyant force acting on the part of the hull, immersed in the foam and, relative to the diametrical plane of the ship, creates an imbalance of buoyant forces acting on its right and left halves and the overturning moment causing the side roll of the ship. During the roll, the side of the vessel is immersed not in water but in foam, which reduces the value of the restoring moment. When the value of the tipping moment is less than the value of the restoring moment, the vessel will turn over.

 The effectiveness of a ship’s upheaval, for example, maintaining positive buoyancy of the vessel, preserving the life of the crew, cargo, neutralizing the combat capabilities of the enemy’s ship, etc., is regulated by the density of the foam, the depth with which it is fed, the foam consumption per unit time and the time it was delivered.

 When a vessel is in a water medium of uniform density, on its left, relatively diametrical plane, and right half of the hull surface below the waterline in the vertical direction, two buoyant forces act, which are equal to each other in magnitude. Each of them is equal in size to half the weight of the vessel, which is concentrated in the center of gravity and is located in its diametrical plane. The points of application of buoyant forces to the hull of the vessel are displaced relative to its diametrical plane by equal distances, respectively, left and right. The buoyant forces create two equal in magnitude, but oppositely directed moments acting on the vessel, which makes their sum equal to zero, and the vessel is stable.

 With a lateral roll, the vessel rises above the water on one side of the hull and plunges into the other with it. The buoyant force acting on the part of the body that has risen from the water will decrease, and the buoyant force acting on the part of the body immersed in water will increase. An imbalance of buoyancy forces creates a restoring moment, which returns the vessel to a vertical position. The buoyant forces acting on the left and right halves of the hull are equal in total to the weight of the vessel, which ensures its positive buoyancy.

 Example 1. To supply foam under the overturned vessel, for example, a submarine with a hydrogen-oxygen type electrochemical generator is used to decompose water into oxygen and hydrogen. Using the technical means of the submarine, the vessel is detected and brought to it. The vessel is being prepared for turning over: stopping the course, closing the hatches of the compartments, portholes, removing the crew, etc. The submarine is submerged under the vessel to the required depth and placed parallel to it.

 The boat is placed taking into account the hydrographic situation (underwater current, its speed, depth, etc.), the direction and speed of the vessel so that the foam, rising up, reaches the hull of the vessel in the section in width from the diametrical plane to the side waterline through which plan overturning, and in length from the bow to the stern, and replaced the water. Compressed gas (air, hydrogen and / or oxygen) is released from the submarine’s tanks, foamed with water or mixed with an aqueous solution of surface-active substances and a foam of the required density and multiplicity is obtained. Gas for foaming water or the finished foam is released through special openings located along the length of the submarine in its upper part from side to side.

 The density of the foam is less than the density of water, therefore, according to the law of Archimedes, it rises. A decrease in the pressure of the water column leads to an increase in the volume of its bubbles, an increase in its multiplicity, and a decrease in density. The multiplicity of the foam can be adjusted from several units to several tens and even hundreds (see Technical means and methods of extinguishing fires / Ed. By B. P. Ivanov. - M.: Energoizdat, 1981, p. 8, 9). Therefore, the density of the foam can be less than the density of water tens and hundreds of times. It is directed under a section of the surface of the ship’s hull in width from the diametrical plane to the side waterline through which it is planned to turn the ship, and in length from the bow to the stern, and replace the volume of water located there.

 Under the vessel, with respect to its diametrical plane, an inhomogeneous density medium is created. Concerning the ship’s diametrical plane, one half of it - from the diametrical plane to the waterline of one side will be immersed in water, and the other half - from the diametrical plane to the waterline of the other side through which they plan to turn over, will be immersed in foam. Since the density of the foam is less than the density of water, the magnitude of the buoyant force acting on the area immersed in it, according to the law of Archimedes, will decrease by so many times, how many times the density of water is greater than the density of the foam. Therefore, the magnitude of the moment of the buoyant force acting on the body from the side of the water will be as many times higher than the moment of the buoyant force acting on the body from the side of the foam.

 This creates a tipping moment, under the influence of which the ship will get a roll on board. During the roll, the side of the vessel through which they plan to turn over will be immersed in foam whose density is less than the density of water. The amount of buoyant force exerted by the foam on this side of the vessel, according to the Archimedes law, will decrease as many times as many times as the density of water is greater than the density of the foam, which will lead to a proportional decrease in the restoring moment and loss of lateral stability of the vessel. When the value of the overturning moment exceeds the value of the restoring moment, the ship will lie on board, and then will roll over and assume a stable position - keel up. Then the ship is towed to the port for repair.

 Example 2. To turn the ship from keel up to keel down, use, for example, a submarine, which is immersed to a predetermined depth. The boat is placed under the keel, turned upside down, parallel to it so that, taking into account the hydrographic situation, the direction and speed of its movement, the foam reaches the vessel and replaces the water on the surface of its hull in width from its diametrical plane to the side through which it is planned to turn over, and in length from bow to stern. The efficiency of the coup is regulated by the density of the foam, the depth with which it is fed, the consumption of foam per unit time and the time it is delivered. The density of the foam should provide a decrease in the buoyancy of the vessel within a positive value. The consumption of foam should ensure its maintenance in the required amount under the hull.

 Foaming is carried out for the time necessary to turn the vessel over. Foam is directed under a section of the surface of the vessel turned upside down with a keel in width from its diametrical plane to the side through which it is planned to turn over, and in length from the bow to the stern and replace it with water. Relative to the ship’s diametrical plane, a medium of inhomogeneous density is created and maintained for the time necessary to turn it over. This creates a tipping moment, causing the side roll of the vessel, and reduce the recovery moment. When the value of the overturning moment exceeds the restoring moment, the ship will lie on board, and then turn over to a stable position - keel down.

 Example 3. Turning over the enemy’s ship, in order to detain it or neutralize its combat capabilities while preserving the life of crew members, is carried out in the following sequence. Using the technical means of the submarine, they find the enemy’s ship, submerge the submarine to the required depth and set it at the rate of its movement in front, taking into account the hydrographic situation, the speed of its movement and the time of foam rising to its hull. They set the speed of the boat, foam the water and direct the foam so that by the time of its rise to the vessel, it will replace the water under the section of its hull in width from the diametrical plane to the side waterline through which it is planned to turn over, and in length from bow to stern, the course of time required to turn the vessel over. When the vessel moves, one half of it, relative to the diametrical plane, is in the water, and the other, during the time necessary for turning over, will be in foam. The buoyant force acting on the hull from the side of the foam is less than the buoyant force acting on the hull of the vessel from the side of the water, so many times how many times the density of water is greater than the density of the foam.

 This creates a tipping moment, causing the side roll of the vessel and reduce the recovery moment. When the value of the overturning moment exceeds the value of the restoring moment, the vessel will lose lateral stability, lie on board, turn upside down, which will neutralize its combat capabilities, preserve its positive buoyancy, and crew members - life. The efficiency of the ship’s revolution is regulated by the density of the foam, the depth with which it is fed, the consumption of foam per unit time and the time it was delivered.

 The method of turning the vessel is illustrated in figure 1 ... 6.

 Figure 1 - forces acting on a ship located in a homogeneous environment.

 Figure 2 - restoring moment, acting when the roll of the vessel in the water.

 Figure 3 - supply of foam under the vessel and the creation of a tipping moment.

 FIG. 4 - turning the ship from the keel down to the keel up position.

 FIG. 5 - the creation of a tipping moment for the vessel, turned upside down keel.

 6 - turning the ship from the position of the keel up to the position of the keel down.

 Where: 1 - the vessel to be turned over; 2 - submarine; 3 - foam; DK - the diametrical plane of the vessel; K - keel of the vessel; About - the center of gravity of the vessel; P is the weight of the vessel; Rv - total buoyancy force; Rl - buoyancy force acting on the left half of the vessel; RP - buoyant force acting on the right half of the vessel; LL - shoulder strength RL; L - the shoulder of the total buoyancy force RV relative to the center of gravity of the vessel; Mv - restoring moment; Mo is the overturning moment; M - metacenter.

 The force P of the weight of the vessel 1 passes through its diametrical plane DK, through the point O of the center of gravity and is directed vertically downward (figure 1). When the vessel is in a water medium of uniform density, then the left and right halves of its hull below the waterline, relative to the diametrical plane, are affected by two equally large buoyancy forces Рл and Рп. Each of them is equal in magnitude to half the weight P of the vessel and half to the total buoyancy force Rv, which ensures its positive buoyancy. The force Pn is shifted relative to the diametrical plane of the DC and the center of gravity of the vessel to the right by a distance Lp, and the force Pl is shifted by the same distance Ll to the left. The forces Рл and Рп are in total equal to the weight Р of the vessel, therefore they provide it with positive buoyancy and create, with respect to the point О of the ship’s center of gravity, two equal in magnitude but opposite directions momentum, which makes them resulting equal to zero, and the vessel is stable.

 When the roll of the ship in water under the action of external forces on the starboard side (figure 2), the buoyancy force Rl decreases, since the left half of the ship leaves the water. The magnitude of the buoyancy force Pn increases, since the vessel with the right half is immersed in water. However, the sum of the forces Pn and Rl remains equal to the total buoyancy force Pb and the weight P of the vessel, which ensures its positive buoyancy. Relative to the center of gravity, the magnitude of the moment of buoyancy force Рп is greater than the value of the moment of buoyancy force Рл, which creates a restoring moment Мв, which returns the vessel to the vertical position. The total buoyancy force Рв intersects the diametrical plane of the vessel at the point M - metacentre, which is located above the point O - center of gravity, which ensures the stability of the vessel.

 To turn vessel 1, for example, from a submarine 2, water is foamed under the gas under it or foam 3 is supplied under it so that it replaces the water under the section of its hull, immersed in water, in width from the diametrical plane of the recreation center to the waterline of the starboard side through which plan to roll over the vessel, and in length from the bow to the stern. The efficiency of the ship’s revolution is regulated by the density of the foam, the depth with which it is fed, the consumption of foam per unit time and the time it was delivered. The density of the foam 3 should provide a decrease in the buoyancy of the vessel 1 within a positive value. The foam consumption should ensure that it is maintained in the required amount under the hull of the vessel 1. The water is replaced with foam, a medium non-uniform in density is created under the vessel relative to its diametrical plane, and it is maintained for the time required for turning over (Fig. 3).

 The left, relative to the diametrical plane, half of the vessel 1 is immersed in water, and the right half is immersed in foam. Since the left half of the vessel is immersed in water, the magnitude of the buoyancy force Rl will remain equal to half the force of the weight of the vessel 1. The moment of force Rl, relative to the point O - the center of gravity of the vessel, will also not change. The density of the foam is less than the density of water. Therefore, the magnitude of the buoyancy force Pn acting on the right half of the ship’s hull will decrease so many times, how many times the density of water is greater than the density of the foam (Fig. 3). This, relative to the point O of the center of gravity of the vessel, proportionally reduces the magnitude of the moment of buoyancy force Pn. When the magnitude of the moment from the force Rl exceeds the magnitude of the moment from the force Pn, a tilting moment Mo will occur.

 The overturning moment Mo will cause the side roll of the vessel 1 to the starboard side (Fig. 4). A lower foam density than water will reduce the buoyancy force Pn, the total buoyancy force Pb and the buoyancy of the vessel within a positive value. As a result, the vessel 1 will receive a roll and begin to sink until the weight of the water and foam displaced by it again reaches its weight. In connection with the substitution of water for a foam whose density is less than the density of water, the metacentre M of the vessel 1 will move below the point O of the center of gravity, and it will lose stability.

 With a lateral roll, the right half of the vessel 1 will sink into the foam. This will cause a reducing moment Мв, however, its value, in comparison with the reducing moment when this half is immersed in water (Fig. 2), will decrease so many times, how many times the density of water is greater than the density of the foam. Under the influence of the overturning moment, the vessel 1 will lie on the starboard side, and then will roll over and assume a stable position with the keel up (figure 5). By the end of the roll, all the foam will rise to the surface of the water and collapse. The vessel will again be in a homogeneous aquatic environment, which will restore its positive buoyancy and stability.

 To turn the vessel 1 from the keel up to the keel down position, use, for example, a submarine 2 (Fig. 5). The boat in the underwater position is installed parallel to the vessel 1, taking into account the hydrographic situation, the direction and speed of its movement so that the foam replaces the water under the section of the vessel in width from its diametrical plane to the port side through which it is planned to turn over, and in length from bow to stern. Foam 3 is directed under the section of the vessel 1 in width from the diametrical plane to the port side, through which they plan to turn over, and in length from the bow to the stern. When the foam reaches the vessel 1, which is turned upside down, the water is replaced with foam in the section from the diametrical plane to the waterline of the port side through which they plan to turn over. They create an inhomogeneous density medium under it, maintain it for the time necessary for turning over. Asymmetric, with respect to the diametrical plane of the vessel and its center of gravity, the substitution of water for foam will create a tipping moment Mo.

 Under the influence of the tipping moment Mo the vessel 1 will receive a roll to the port side (Fig. 6). Since the magnitude of the buoyancy force Rl will decrease, in comparison, if the left half were immersed in water, then the total buoyancy force Rb will decrease. The density of the foam is set less than the density of water so as to reduce its buoyancy, but within the limits of positive buoyancy. Therefore, the vessel 1 will receive a roll and begin to sink until the weight of the water and foam displaced by it again reaches its weight.

 Immersion of the left half of the hull in the foam during the roll of the vessel will cause the appearance of a restoring moment Мв. However, its value, in comparison, if the left half would be immersed in water, will decrease so many times, how many times the density of water is greater than the density of the foam. The metacentre M will move below the center of gravity O, and vessel 1 will lose lateral stability. Under the influence of the overturning moment Mo, the vessel 1 will lie on the port side and roll over to the stable position with the keel down (Fig. 1). At this point in time, all the foam will rise from the depths to the surface of the water and collapse, which will restore an aquatic environment of uniform density under the vessel. The vessel will retain its positive buoyancy, restore lateral stability and float to the water surface keel down. The efficiency of the ship’s revolution is regulated by the density of the foam, the depth with which it is fed, the consumption of foam per unit time and the time it was delivered.

Claims (2)

1. The method of turning the vessel, including the creation of a tipping moment acting on this vessel, characterized in that the tipping moment is created by replacing water under a section of the hull, the width from the diametrical plane to the waterline of the side through which the vessel is turned over and the length from the bow to the stern, with foam supplied from a submarine located at a depth below the vessel or formed by foaming water with compressed gas supplied from this boat and directed under the ship's hull for a time sufficient for coup from keel down to keel up or vice versa. 2. The method according to claim 1, characterized in that the efficiency of the coup is controlled by the density of the foam, the depth with which it is supplied, the consumption of foam per unit time and the time of its supply.

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