RU2381948C1 - Method to produce channels in ice sheet - Google Patents

Abstract

FIELD: transport.

SUBSTANCE: proposed method consists in that two bars with electrodes are pulled out on ice breaker sides and heated by electric current generated aboard ice breaker. Ice breaker is moved the bars length. Two cuts are heated in ice depth for ice breaker to break up loose ice eased by said cuts, and ice breaking cycle is repeated. Electrodes representing plates, their front ends being sharpened upward, are forced into ice partially, and ice breaker speed is adjusted in compliance to power of current fed to electrodes.

EFFECT: reduced power consumption, ice breaker higher efficiency.

Description

The invention relates to icebreaking shipbuilding and, in particular, to icebreaking operations.

Known methods of ice cover destruction have not been developed due to the large discrepancy between the energy on board the icebreakers and the energy required for ice destruction.

So, there is a known method of ice destruction according to copyright certificate No. 1548978, according to which ice is blown up on the way of an icebreaker.

The known method according to RF patent No. 2081025, in which ice is destroyed by rocking the vessel and creating a wave in addition to the running wave.

There is also known a method according to RF patent No. 2086464, in which ice is hacked by the hull of a submarine.

Known underwater surface ice navigation vessel according to the patent of the Russian Federation No. 2172698, breaking ice with its wedge-shaped hull.

There is a method according to RF patent No. 2326785, according to which an apparatus is developed from an icebreaker under ice, developing an Archimedean force of up to 100 tons. With this force, applied to a sharp rib, ice is destroyed and the apparatus is moved further.

A known method of destroying ice cover according to the patent of the Russian Federation No. 2314963. In this way, air is pumped under the ice, causing ice to collapse.

There is a method according to the patent of the Russian Federation No. 212505, according to which cutters are cut on the bow of the icebreaker, cutting through the ice before breaking it by the icebreaker body.

There is also known a method according to RF patent No. 2213675, in which jets of water, a steam-water mixture or steam are supplied to the ice through the bow of a ship.

The known method according to the patent of the Russian Federation No. 2085432, according to which for the ascent of a submarine from under the ice, rods are brought to it and warm water is supplied. Water heats the slots around the perimeter of the boat and the hull of the boat breaks the ice and brings the boat to the surface.

A known method of breaking ice in front of a ship using an electric arc, see RF patent No. 2216477.

There is also known a method No. 2144454, according to which for surfacing a submarine extend the rods with electrodes and supply power. In the thickness of the ice, the cracks melt and, removing the electrodes, break the ice with the hull of the boat.

The latter method is adopted as a prototype of the invention.

The known method has serious disadvantages. When ice is destroyed by heating, a significant amount of energy is consumed, the bulk of which is the heat of melting of the ice. Therefore, the width of the slots should be minimal. In addition, the time of energy transfer directly depends on the magnitude of the heat flux or on the temperature difference between the hot and cold body. This difference is actually tens of degrees. When ice melts, the water flowing onto the electrodes is heated by their hot surfaces and carries away a significant part of the energy. Thus, the known method is too energy-consuming, uneconomical.

When creating channels in ice fields, especially with a large thickness of ice, energy costs and terms of work can become unacceptably large.

The aim of the present invention is to reduce energy consumption for the destruction of the ice cover and increase efficiency and productivity.

The goal is achieved when creating channels in the ice cover in a way by which two rods with electrodes that advance with current generated on board the icebreaker are advanced along the icebreaker, push the icebreaker to the length of the rods, melt two slots in the ice, break the ice weakened by the slots and repeat the ice breaking cycle.

The essence of the invention lies in the fact that the electrodes, made in the form of plates, in front of the pointed upwards, are buried in ice only to a part of the thickness of the ice, and the speed of the icebreaker is controlled by the power of the supplied current.

When laying a canal in an ice field, the size of the work should be extremely limited. So, the width of the slots made in ice and the thickness of the plates of the electrodes can be only a few millimeters. The height of the electrode plates can be much less than the thickness of the ice layer. When the ice melts, the water generated is heated from the electrode and, flowing down from the slot, heats a groove in the lower part of the ice, in which the heat carried away by it is taken from the water. To reduce the entrainment of heat, the electrode plate is made in the working part pointed up. The back of the electrode plate must be made of a material with low electrical conductivity or insulated. The departure of the rods carrying the electrodes should be designed to create a destructive bending moment under the influence of the weight of the front of the icebreaker, which is pushed onto the cut ice. After breaking off the ice, it falls into the water and is crushed by the mass of the icebreaker.

When the channel is drilled by this method, the penetration rate depends mainly on the flow rate of the melted ice, that is, on the power supply of the electrodes. Since the total amount of work is saved, it is advisable to increase this power to increase the penetration rate.

The technical result of the present invention is the possibility of economical and fairly fast laying of ice canals. The main equipment - icebreakers - can be used from among those operating and tested in the north or under construction. At the same time, the devices and equipment required for them remain simple and uncomplicated. The energy costs of the work are paid off many times by the opening opportunities for the transport of goods in the north.

The invention is illustrated by examples.

Example 1. An icebreaker with a displacement of 3000 tons paves a channel 10 m wide in the ice sheet of the river with an ice thickness of 1.2 m. The icebreaker is equipped with two rods with a reach of 12 m. An aluminum electrode 5 mm thick is fixed on each rod, immersed in ice by 0.8 m. The electrodes during operation are powered by a current with a total capacity of 5.0 MW.

During operation, the electrodes are heated to a temperature of 70 ° C at a temperature in the air and on the ice surface of -20 ° C. During ice penetration, the current power is spent on heating and melting the ice and heating the water. At a ship speed of 2 knots, each electrode heats and melts 4 kg / s of ice and heats water to 40 ° C, which melts another 2 kg / s of ice, cutting the ice to its full thickness. When loading the cut ice with a part of an icebreaker weighing 500 tons, the bending moment in the fixed section of the ice is 6,000 tons, which leads to cleavage of the ice.

To increase the channel penetration rate, it is necessary to increase the power supply of the electrodes accordingly.

Example 2. A marine icebreaker with a displacement of 15 thousand tons paves a canal with a width of 30 m in an ice sheet with an ice thickness of 3.0 m. The icebreaker is equipped with two rods with a reach of 15 m. An aluminum electrode 8 mm thick is fixed on each rod, buried in ice by 2 , 0 m. The electrodes during operation are powered by a current with a total capacity of 20 MW. During operation, the electrodes are heated to a temperature of 80 ° C at a temperature in the air and on the ice surface of -20 ° C.

At a ship speed of 2 knots, each electrode heats and melts 16 kg / s of ice and heats water to 40 ° C, which melts another 8 kg / s of ice, cutting the ice to its full thickness. When loading the cut ice with a part of the icebreaker weighing 3,000 tons, the bending moment in the fixed section of the ice is 45 thousand tons, which leads to ice cleavage.

Example 3. A sea icebreaker with a displacement of 40 thousand tons paves a canal 30 m wide in an ice sheet with an ice thickness of 6.0 m. The icebreaker is equipped with two rods with a reach of 18 m. An aluminum electrode 10 mm thick is fixed on each rod, buried in ice by 4 m. The electrodes during operation are powered by a current with a total capacity of 46 MW. During operation, the electrodes are heated to a temperature of 90 ° C at a temperature in the air and on the ice surface of -20 ° C.

At a vessel speed of 2 knots, each electrode heats and melts 40 kg / s of ice and heats water to 40 ° C, which melts another 20 kg / s of ice, cutting the ice to its full thickness. When loading the cut ice with a part of the icebreaker weighing 5 thousand tons, the bending moment in the fixed section of the ice is 90 thousand tons, which leads to ice cleavage.

The proposed method of ice penetration has a large area of civil and defense applications.

So, all the northern rivers of the country can become navigable throughout the year. Arctic areas can be accessed by the Northern Fleet without restrictions. The upcoming development of the Arctic shelf deposits will be provided with the delivery of equipment and products. On the other hand, the northern submarine fleet will have reliable supply bases at several different points in the ocean. Laying channels along ice fields also allows you to create and maintain airbases and airfields in the northern regions, difficult and dangerous for flights.

Claims (1)

The method of creating channels in the ice cover, along which two rods with electrodes are put forward along the icebreaker, which are heated by the current generated on board the icebreaker, advance the icebreaker to the length of the rods, melt two slots in the ice, break the ice weakened by the slots and repeat the destruction cycle ice, characterized in that the electrodes made in the form of plates, in the front part pointed upwards, are buried in ice only to a part of the ice thickness, and the speed of the icebreaker is controlled by the power of the supplied current.