RU2303550C1 - Facility for reducing ship hydrodynamic resistance - Google Patents

Abstract

FIELD: shipbuilding; facilities for reducing ship hydrodynamic resistance through introduction of various agents into boundary layer.

SUBSTANCE: proposed facility has holes or slots with flexible fairing over perimeter of underwater hull which are connected with mixer outlet by means of pipe line fitted with metering device through manifold. Used as mixer is transonic jet apparatus - pump-mixer which generates working medium in form of homogeneous two-phase gas-and-water or vapor-and-water mixture where fraction of gas (air, vapor) ranges from 20 to 90%. Holes or slots are combined in autonomous sections (bottom sections, side sections, deck sections, appendages); each section is provided with its own manifold and sectionalized pipe line fitted with metering device. Sectionalized pipe lines are connected with common pipe line which is connected in its turn with mixer outlet. First inlet of mixer is connected via metering device with water source (outside water, for example) and its second inlet is connected with gas, air or vapor source by means of pipe line fitted with metering device.

EFFECT: reduced resistance to motion; reduced fuel consumption.

5 cl, 3 dwg

Description

The invention relates to shipbuilding, in particular to devices for reducing the resistance of ships by introducing into the boundary layer of the hull of the vessel a working medium in the form of various kinds of substances (polymers, gases, air, water-repellent grease, etc.). Allows you to simplify the device, increase its efficiency.

A device for supplying a working medium in the form of a polymer solution to the boundary layer of a ship’s hull, containing a mixer, holes or slots with a cowl around the hull perimeter, is connected through a manifold to a pipeline that is connected to the mixer (USSR copyright certificate No. 1068325, 1984). Taken as a prototype.

The disadvantages of the device are the need to carry a consumable polymer, while the design of the device is quite complicated, the efficiency of the supply of the solution of the substance is relatively low, since there is no adjustment of the parameters of the solution depending on the feed place in the hull (side, bottom, upper part of the hull).

There is a method of reducing the hydrodynamic resistance to the movement of bodies, which consists in creating an electromagnetic field in the boundary layer that generates complexes of molecules (instead of polymers) (USSR copyright certificate No. 364483, 1972).

The disadvantage of this method is the need for consumable iron and / or aluminum electrodes on the outer body.

A device is known for reducing the friction resistance of an object moving in water, containing a shell with cells covering the body of the object, with holes for releasing water-repellent lubricant on the outer surface of the shell (USSR author's certificate No. 1726308, 1992).

The disadvantages of the device are the need to carry consumable water-repellent grease or lubricant ingredients for manufacturing it on board the vessel, the bulkiness of the structure, low reliability and survivability, difficulties in repair.

The technical result of the invention is to simplify the design of the device, increase the efficiency of the device, namely: increasing the degree of use of the working environment and reducing the hydrodynamic resistance of the vessel, no need to carry consumables, materials.

The technical result is achieved by the fact that in the known device having a mixer, holes or slots with a cowl around the perimeter of the housing, connected through a collector to the mixer, a transonic jet apparatus — a Fisenko mixer-pump — is used as a mixer, and produced as a working medium in the mixer homogeneous (homogeneous) gas-water or steam-water two-phase mixture (hereinafter - the two-phase mixture). In this case, the proportion of gas (air, steam) is from 0.2 to 0.9, which ensures a two-phase mixture flow rate at the apparatus outlet of 20-100 m / s. Holes or slots around the perimeter of the underwater hull in the plane of the ship’s frame are combined into autonomous sections (bottom, side, deck, protruding parts of the hull), each section having its own manifold and piping with a metering device. Sectional pipelines are connected to a common pipeline or to the outlet of a sectional mixer. The first input of the mixer is connected by a pipeline equipped with a metering device to a source of water (for example, from an outboard), the second input of the mixer is connected by a pipe (with a metering device) to a source of gas or air (steam). The source of steam may be, for example, a steam boiler of a ship.

Figure 1 shows the structural and hydraulic diagrams of the proposed device, figure 2 - the location of the sectional collectors around the perimeter of the underwater part of the vessel with pipelines, figure 3 - placement of the device on the surface vessel and underwater vehicle.

The device for supplying a two-phase mixture to the surface of the ship’s hull contains a mixer 1, holes or slots 2 with a cowl 3, located in the bow of the vessel along the perimeter of the immersed part of the hull 4 and connected through a manifold 5 to a pipeline 6, which is connected to the output 7 of the mixer 1. The first input 8 mixer 1 is connected by a pipe 9 (with a metering device 10). The second input 11 of the mixer 1 is connected by a pipe 12 (with a metering device 13) to a source of gas or air (steam) 14.

On figa collector 5 at the surface vessel is divided for example into 3 autonomous sections (two side and one bottom). Each section has a sectional pipe 15 (15a, 15b) with metering devices 16 (16a, 16b). Sectional pipelines 15 are connected to a common pipeline 6. The device has one common mixer with equipment 17, shown in figure 1.

In option 2 of the layout of the device, each section has its own mixer with all the necessary equipment 17.

With option 3, the side sections can have a common mixer, and the bottom section has its own mixer, with the necessary equipment 17.

For the underwater vehicle (fig.2b) there are 4 possible layout of the device. In option 1, the collector may consist of 4 sections: two airborne 5a, bottom 5b and upper section 5c. In this case, one set of equipment 17 and four sectional pipelines with metering devices are used.

In option 2, each of the sections has its own mixer with the corresponding equipment 17.

In option 3, the collectors of the airborne sections have one common pipeline with a metering device. The pipelines of the side sections, bottom and top sections are connected to the pipeline 6.

In option 4, the side sections with a common pipeline with a metering device, the bottom and top sections have an independent mixer.

The device operates as follows.

To start the device, water (for example, outboard) is supplied to the mixer 1 through the first inlet 8 through a pipeline 9. The water flow rate is adjusted by a metering device 10. Through the second inlet 11 of the mixer gas or air (steam) is supplied from a gas or air source 14 through a pipeline 12 The adjustment of the flow rate and pressure of gas or air is carried out by the metering device 13. In the case of using steam, its source 14 may be a steam boiler of the vessel. As a mixer, the Fisenko transonic inkjet apparatus is used (ed. St. No. 966326, publ. 1982; ed. St. No. 1699564, publ. 1991; RF patent No. 2016261, publ. 1994; RF patent No. 2155280 , publ. 2000), which is both a mixer and a pump. In mixer 1, water and gas enter the mixing chamber, where a two-phase mixture flows, which is then inhibited with increasing pressure in the stream to a certain value, which, while maintaining a two-phase state, provides a predetermined flow rate at the mixer output.

In the mixer 1, a homogeneous (homogeneous) gas-water (steam-water) two-phase mixture with microscopic gas (steam, air) inclusions is formed, which is transported through pipeline 6 to the collector 5 and from it through openings (slots) 3 to the boundary layer on the ship's hull 4. Properties two-phase mixtures are determined by volumetric ratios of its components. If the volumes of water and gas (steam) and the speed of the two-phase mixture at the mixer exit are higher than the speed of sound propagation in the two-phase mixture, there is a minimum (almost zero) friction resistance of this mixture on the surface of the body and in pipelines (V. Fisenko “ The compressibility of the coolant and the efficiency of the circulation circuits of nuclear power plants ". M: Energoatomizdat, 1987).

The presence of several independent sections of the collectors can improve the efficiency of using the flow of a two-phase mixture, especially for a surface vessel. When the vessel is pitching and there is one collector, the two-phase mixture, having a lower density than sea water, will tend to float, while bare (without flowing around the two-phase mixture) sections of the ship's hull will appear, and the effectiveness of reducing the resistance of the vessel as a whole will decrease. An increase in the feed rate of the two-phase mixture through the side sections, leaving the feed through the bottom section the same, will compensate for the indicated influence of pitching.

A single collector is completely unsuitable for vessels (for example, tankers), which have a large difference in draft when they are loaded and empty when crossing the sea.

The proposed device will significantly reduce the resistance to movement of surface ships, underwater vehicles, thereby reducing fuel consumption and the time of delivery of goods and passengers to ports of destination.

Claims (5)

1. A device for reducing the hydrodynamic resistance of a vessel, comprising a mixer for generating a working medium, openings or slots with a cowl around the perimeter of the hull, connected by a pipe through a collector to a mixer, characterized in that a transonic jet apparatus - a Fisenko mixer-pump is used as a mixer, and a working one medium - in the form of a homogeneous two-phase gas-water or steam-water mixture generated in the mixer, in which the proportion of gas (air, steam) is from 20 to 90%, holes or slots with a fairing around the perimeter along water body parts are combined into autonomous sections (bottom, side, deck, protruding body parts), each section has its own sectional collector and sectional pipeline with a metering device, and sectional pipelines are connected to a common pipeline connected to the mixer outlet, with the first input of the mixer through a metering device connected to a source of water (for example, with an outboard), the second inlet of the mixer is connected by a pipe through a metering device to a source of gas, air or steam. 2. The device according to claim 1, characterized in that the fairing is made of flexible materials more tenacious during operation than solid materials. 3. The device according to claim 1, characterized in that the collector of the surface vessel is made of two side sections and a bottom section connected by a pipeline, while the side and bottom sections have common or separate mixers. 4. The device according to claim 1, characterized in that the collector of the submarine vessel (apparatus) is made of two side sections connected by a pipeline, the bottom and deck sections, while all or separate sections have their own mixers. 5. The device according to claim 1, characterized in that the holes or slots with a collector are located in the bow of the protruding part of the submarine vessel (apparatus) and are connected to a common pipeline or have their own mixer.

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