Dewar for superconducting magnetic levitation

Abstract

The invention discloses a Dewar for superconducting magnetic levitation which comprises a shell, a plurality of layers of heat insulators and an inner container which are sequentially arranged from outside to inside, a superconducting magnet is further fixed between the shell and the inner container, the space between the shell and the inner container is vacuumized, and a liquid conveying pipe extending into the inner container is installed on the shell. The liquid conveying pipe is provided with a two-section structure of a stainless steel tube and a glass steel tube, so that heat leakage isreduced, vaporization of low-temperature liquid is reduced, liquid nitrogen is prevented from being blown away during liquid supplementation, and liquid supplementation loss is reduced; supporting columns abutting against the superconducting magnet are arranged at the bottom of the shell, first reinforcing ribs are welded to the outer side wall of the shell, second reinforcing ribs are welded to the inner side wall of the inner container, the first reinforcing ribs, the second reinforcing ribs and the supporting columns improve the rigidity of the bottom of the Dewar, rigidity is enhanced under the condition that it is guaranteed that the thickness of the bottom face of the inner container and the bottom face of the shell does not exceed 3 mm, and deformation is avoided. Therefore, the heat insulation performance of the Dewar is fundamentally improved; meanwhile, the design can also reduce the weight, shorten the spacing distance between the magnets and improve the equipment performance.

Description

technical field [0001] The invention relates to the field of superconducting technology, in particular to a Dewar used for superconducting magnetic levitation. Background technique [0002] The superconducting maglev train is a train that uses superconducting magnets to float the car body, and obtains propulsion power by periodically changing the direction of the magnetic poles. It is a high-speed train developed by Tokai Railway Co., Ltd. in Japan. During the test, the maximum speed reached 590 km, the fastest train ever built. In addition, superconducting maglev trains are not only fast, but also have no noise, no vibration, energy saving, and reduce the increase in operating costs caused by maintenance of track wear due to high-speed trains running at a speed of 350km / h. The characteristics of reduced safety, all these characteristics indicate that the superconducting maglev train is expected to become the main force of transportation in the 21st century. [0003] Human...

AI Technical Summary

Problems solved by technology

[0005] At present, the Dewar used for superconducting magnetic levitation generally adopts a conventional multi-layer thermal insulation structure, which is generally composed of a shell, a multi-layer thermal insulation structure and an inner tank from the outside to the inside, and a superconducting magnet block is fixed between the outer shell and the inner tank. The vacuum setting between the outer shell and the inner tank will cause the following problems under working conditions: (1) The surface of the outer shell and the inner tank is flat, and there is no support column, so it is easy to deform under the action of the internal and external pressure difference, which will destroy the vacuum ;(2) Since the distance between the inner tank and the outer shell is very small, the deformation of the inner tank and the outer shell will cause the multi-layer heat insulation structure to be compacted, thereby increasing the heat conduction through the heat insulating material itself and reducing the heat insulation efficiency; (3) The superconducting magnet block has not been pretreated, and the amount of outgassing is large, which will cause the vacuum in the adiabatic space to deteriorate; (4) There is no getter in the adiabatic space, and the vacuum is not up to standard

Therefore, the overall heat insulation effect is poor, and the equipment performance is not ideal; (5) using a single tube for rehydration, the heat leakage is large, the loss of rehydration is also large, and the economy of long-term operation is poor

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