RU2149794C1 - Method of breaking ice cover - Google Patents

Abstract

FIELD: shipbuilding; submersible vessels breaking ice cover by resonance flexural gravitational waves. SUBSTANCE: method consists is directing mass of water thrown by ship's propeller under wave crest. EFFECT: enhanced efficiency of ice breaking. 2 cl, 1 dwg

Description

 The invention relates to the field of shipbuilding, in particular to submarines, destroying the ice cover by the resonant method (1. Kozin V.M. Resonance method of ice cover destruction. Thesis for the degree of Doctor of Technical Sciences in the form of a scientific report. - Vladivostok, IAPA FEB RAS , 1993, 44 pp.).

A technical solution is known (2. Kozin VM, Onishchuk AV Model studies of wave formation in continuous ice cover from the movement of a submarine / ПМТФ, Novosibirsk: Nauka, 1994. N 2. P. 78-81), which proposes to destroy the ice cover by an underwater vessel by excitation of flexural-gravitational waves in ice when it moves with a resonant speed v _p , i.e., at a speed at which the amplitude of the excited flexural-gravitational waves (IGW) is maximum.

The disadvantage of this method is the impossibility of increasing the amplitude of IGV, i.e. its ice-breaking ability when the vessel is moving at a speed of v _p .

 The essence of the invention lies in the development of a method for increasing the amplitude of IGW excited during the translational motion of an underwater vessel.

 The technical result obtained by carrying out the invention is to increase the efficiency of ice destruction by an underwater vessel in a resonant manner.

 The essential features characterizing the invention.

 Restrictive: the ice cover is destroyed by an underwater vessel by excitation of resonant IGW in ice.

 Distinctive: under the first crest of the vessel, the waves increase the pressure by directing under the crest the masses of water discarded by the ship's propeller.

 The method is as follows.

 Under the ice cover at a given depth, a submarine begins to move at a resonant speed. If the amplitude of the IGW excited in this case is insufficient to destroy the ice cover, then under the first behind the stern of the wave, the wave crest, whose height is maximum in comparison with other ridges [2], direct the masses of water discarded by the ship’s propeller. To do this, the vessel trim on the bow. The jet of water thrown by the propeller, striking the lower surface of the ice, will lose its speed. At the same time, its kinetic energy will partially turn into potential energy of increased pressure. An increase in pressure under the crest of the wave will cause an increase in its height, i.e., the amplitude of the IGW behind the stern of the vessel will increase. In turn, this will lead to an increase in bending stresses and an increase in the efficiency of ice destruction by an underwater vessel in a resonant manner.

 The invention is illustrated in the drawing, which shows a diagram of its implementation.

Under the ice cover 1 at a given depth H begins the movement of the submarine 2 with a resonant speed v _p . If the amplitude of the IGV-3 excited in this case is insufficient to break the ice, then during the movement under the first stern of the vessel the wave crest is guided by a stream of water 4 thrown by the propeller 5. For this, the vessel is trimmed onto the bow (position 6). A jet of water 4, hitting the lower surface of the ice, will decrease its speed, which will cause an increase in the amplitude of IGV-7 and a corresponding increase in the efficiency of ice destruction.

Claims (1)

 A method of destroying ice cover by an underwater vessel by exciting resonant bending-gravitational waves in ice, characterized in that under the first crest of the vessel, the waves increase pressure by directing under the crest the masses of water discarded by the ship's propeller.