CN114221491B

CN114221491B - Superconductive motor rotor heat exchanger structure

Info

Publication number: CN114221491B
Application number: CN202111474776.3A
Authority: CN
Inventors: 李妍; 何大瑞; 韩笑; 王琼
Original assignee: Economic and Technological Research Institute of State Grid Jiangsu Electric Power Co Ltd
Current assignee: Economic and Technological Research Institute of State Grid Jiangsu Electric Power Co Ltd
Priority date: 2021-12-02
Filing date: 2021-12-02
Publication date: 2023-07-14
Anticipated expiration: 2041-12-02
Also published as: CN114221491A

Abstract

The invention relates to a heat exchanger structure of a superconducting motor rotor, wherein a through hole is formed in the center of the rotor, the heat exchanger structure is arranged in the through hole, the heat exchanger structure comprises a plurality of heat exchanger units and a baffle plate, the heat exchanger units are sequentially arranged along the axial direction of the through hole, the baffle plate is arranged between every two adjacent heat exchanger units, and each heat exchanger unit comprises a fin heat exchanger and gaskets arranged on two sides of the fin heat exchanger; the outer diameters of the fin heat exchanger, the gasket and the partition plate are matched with the diameters of the through holes, and a plurality of heat exchange holes which are uniformly distributed along the circumferential direction of the fin heat exchanger are formed in the fin heat exchanger; the gasket is annular, and the inner space forms a disc-shaped air cavity; an air hole is arranged in the center of the partition board; both ends of the heat exchange hole and the air hole are respectively communicated with the air cavities of the corresponding gaskets; end flanges are arranged at the two ends of the rotor corresponding to the through holes, a cooling pipe is arranged at the center of each end flange, and the cooling pipes are communicated with an air cavity of an end gasket of the heat exchanger structure; the heat exchanger structure of the invention has uniform flow distribution and high heat transfer efficiency.

Description

Superconductive motor rotor heat exchanger structure

Technical Field

The invention relates to a heat exchanger structure of a superconducting motor rotor, and belongs to the technical field of heat exchange of superconducting motors.

Background

Motors and generators based on high temperature superconducting technology have a series of advantages of small volume, light weight, low loss, high efficiency and the like, so that great benefits of the superconducting motor in terms of cost, volume, weight and the like will cause great transformation of the whole motor manufacturing industry in the near future.

The cooling system of the high-temperature superconducting motor comprises a cooling system of a rotor and a cooling system of a stator. The cooling system of the rotor is used for timely taking away the loss generated by the superconducting coils and other magnetic materials when the motor works and the heat transmitted to the rotor by the external environment, keeping the superconducting state of the coils and ensuring the continuous normal operation of the motor, and is one of the main differences of the superconducting motor and the common motor.

The main part of the cooling system of the rotor is a cooling loop in the rotor, and the basic arrangement mode is that a plurality of pipelines are processed on a basic and rotating framework of the superconducting coil, and the pipelines are connected with a low-temperature air inlet/liquid inlet pipe and cool the superconducting coil through a low-temperature medium in the pipelines. This structure has the following problems: the difficulty of processing grooves for placing pipelines from a thin coil substrate is high, and the thin substrate is extremely easy to deform; the pipeline and the substrate groove always have a certain gap, and epoxy resin is generally adopted for filling at present, and the thermal conductivity of the epoxy resin is lower, so that the heat transfer efficiency is greatly influenced; the pipelines need to be connected in series and in parallel, wherein the series connection leads to increased flow resistance and larger temperature difference between the head and the tail, and the parallel connection leads to uneven gas/liquid flow distribution, thereby affecting the heat transfer effect and the uniformity of the temperature distribution of the whole structure; the structure processing amount is large, and the processing precision is high; the pipelines are more, the connecting joints are more, and the problem of vacuum leakage is easy to occur.

Disclosure of Invention

The invention provides a superconductive motor rotor heat exchanger structure with uniform flow distribution and high heat transfer efficiency, which aims to solve the problems in the prior art.

In order to achieve the above purpose, the technical scheme provided by the invention is as follows: the heat exchanger structure of the superconducting motor rotor is characterized in that a through hole is formed in the center of the rotor, the heat exchanger structure is arranged in the through hole, the heat exchanger structure comprises a plurality of heat exchanger units and a partition plate, the heat exchanger units are sequentially arranged along the axial direction of the through hole, the partition plate is arranged between every two adjacent heat exchanger units, and each heat exchanger unit comprises a fin heat exchanger and gaskets arranged on two sides of the fin heat exchanger; the outer diameters of the fin heat exchanger, the gasket and the partition plate are matched with the diameters of the through holes, and a plurality of heat exchange holes which are uniformly distributed along the circumferential direction of the fin heat exchanger are formed in the fin heat exchanger; the gasket is annular, and a disc-shaped air cavity is formed in the inner side space of the gasket; an air hole is formed in the center of the partition plate; both ends of the heat exchange hole and the air hole are respectively communicated with the air cavities of the corresponding gaskets; the two ends of the rotor are provided with end flanges corresponding to the through holes, the centers of the end flanges are provided with cooling pipes, and the cooling pipes are communicated with the air cavities of the washers at the ends of the heat exchanger structure.

The technical scheme is further designed as follows: the heat exchangers Kong Jie are strip-shaped and are radially arranged along the fin heat exchanger.

The part between the outer surface of the fin heat exchanger and one end, close to the outer diameter, of the heat exchange holes is an outer ring, and the part between the center of the fin heat exchanger and one end, close to the center, of the heat exchange holes is an inner core; the inner diameter of the gasket is matched with the inner diameter of the outer ring of the fin heat exchanger, and the diameter of the air hole is smaller than the diameter of the inner core of the fin heat exchanger.

The thickness of the fin heat exchanger is larger than that of the gasket, and the thickness of the gasket is larger than that of the partition plate.

And a sealing ring is arranged between the end flange and the end of the rotor.

Compared with the prior art, the invention has the following beneficial effects:

the heat exchange holes in the heat exchanger structure are uniformly distributed along the circumference, so that the flow resistance among all transmission channels is balanced, the parallel gas/liquid branches are uniformly distributed, and the heat transfer efficiency is high; meanwhile, the flow resistance of the heat exchange structure is small, so that the pressure drop of the low-temperature medium along the transmission direction can be reduced, the friction heat generation and the working pressure of the low-temperature pump are reduced; the heat exchanger has large overall heat capacity and short transmission path, so that the temperature difference between the head and the tail of the heat exchanger is lower, and the overall temperature distribution is uniform.

The heat exchanger has the advantages of simple structure, small processing amount, no complex assembly precision requirement and simple assembly; the heat exchange area can be flexibly adjusted according to the heat exchange power; and only 2 sealing structures are provided, so that the reliability is high.

Drawings

FIG. 1 is a schematic diagram of a rotor structure in an embodiment of the present invention;

FIG. 2 is a schematic view of the heat exchanger of FIG. 1;

FIG. 3 is a schematic view of the fin heat exchanger of FIG. 2;

fig. 4 is a schematic view of the rotor end element of fig. 1.

In the figure: 1-heat exchanger, 11-fin heat exchanger, 111-outer ring, 112-fin, 113-inner core, 114-outer surface, 115-heat exchange hole, 12-gasket, 13-separator, 131-air hole, 14-air cavity, 2-superconducting motor rotor, 3-end member, 31-end flange, 32-cooling tube, 33-sealing ring.

Detailed Description

The invention will now be described in detail with reference to the accompanying drawings and specific examples.

Examples

As shown in fig. 1, in a heat exchanger structure of a superconducting motor rotor of the present embodiment, the heat exchanger structure is disposed at a central position of the superconducting motor rotor 2, a through hole is disposed at the center of the superconducting motor rotor 2, and the heat exchanger structure 1 is disposed in the through hole and is used for conducting cold energy of a low-temperature medium to the superconducting motor rotor 2, and conducting external heat generated and absorbed by the superconducting motor rotor 2 to a circulating low-temperature medium, so as to maintain the superconducting motor rotor 2 to work in a target temperature zone.

As shown in fig. 2, the heat exchanger structure 1 includes a plurality of heat exchanger units sequentially arranged in the axial direction of the through hole and a separator 13 arranged between adjacent heat exchanger units, each heat exchanger unit includes a fin heat exchanger 11 and gaskets 12 arranged on both sides of the fin heat exchanger 11; the superconducting motor rotor 2 is provided with end members 3 at both ends, the end members 3 being used for fixing the heat exchanger structure 1 together with the superconducting motor rotor 2 and providing a gas-cooled heat exchanging space for the heat exchanger structure 1.

As shown in fig. 2, the outer diameters of the fin heat exchanger 11, the gasket 12 and the partition 13 are all matched with the diameters of the through holes, and in combination with fig. 3, a plurality of heat exchange holes 115 are uniformly distributed on the fin heat exchanger 11 along the circumferential direction of the fin heat exchanger 11, the cross sections of the plurality of heat exchange holes 115 are in a strip shape, the heat exchange holes are radially arranged along the fin heat exchanger 11, an annular part between the outer surface 114 of the fin heat exchanger 11 and one end, close to the outer diameter, of the plurality of heat exchange holes 115 is an outer ring 111, a cylindrical part between the center of the fin heat exchanger 11 and one end, close to the center, of the plurality of heat exchange holes 115 is an inner core 113, and a part between the inner core 113 and the outer ring 111 is divided into a plurality of fins 112 by the plurality of heat exchange holes 115; the gasket 12 is annular, and the inner space forms a disc-shaped air cavity 14; the center of the baffle 13 is provided with an air hole 131; both ends of the heat exchange hole 115 and the air hole 131 are respectively communicated with the air cavity 14 of the adjacent gasket 12; the inner diameter of the gasket 12 is matched with the inner diameter of the outer ring 111 of the fin heat exchanger, and the diameter of the air hole 131 is smaller than the diameter of the inner core 113 of the fin heat exchanger.

The fin heat exchanger 11 is made of copper, aluminum and other materials with high heat conductivity; the fin heat exchanger 11 is cylindrical and has the thickness of 100-200mm, and because the fin heat exchanger 11 needs to rotate at a high speed when in use, in order to ensure that the fins 112 do not deform under the high-speed rotation, the fins 112 are positioned in the outer ring 111 of the cylindrical fin heat exchanger 11, all the fins 112 form a whole through the inner core 113 and the outer ring 111, and all the fins 112 are uniformly distributed along the circumference, so that the dynamic balance and the structural strength of the whole structure are ensured; the outer surface 114 of the fin heat exchanger 11 is a surface layer which is smooth and clean, so that the fin heat exchanger 11 can be just coaxially sleeved in the central through hole of the superconducting motor rotor 2; during assembly, the outer surface 114 of the fin heat exchanger 11 needs to be coated with a low-temperature heat conducting material, and silicone grease with high heat conducting property at low temperature, such as a Pi Songzhi, can be generally adopted to ensure better heat conducting contact between the outer surface 114 and the central through hole of the superconducting motor rotor 2, so that the heat conducting property is improved.

The gasket 12 is a circular ring structure and is made of the same material as the fin heat exchanger 11, and the inner diameter of the gasket is equal to or slightly smaller than that of the outer ring 111; the gasket 12 is mainly used for forming an air cavity 14 for the fin heat exchanger 11, so that the thickness of the gasket is not too small, and the selected size is 10-20mm in the embodiment so as to provide a buffer area for the low-temperature medium and ensure that the low-temperature medium can uniformly flow through the fin heat exchanger 11.

The baffle 13 is of a circular ring structure and is made of the same material as the fin heat exchanger 11; the diameter of the central air hole 131 is 20-30mm, and is mainly used for providing a flow channel for a low-temperature medium; the thickness of the partition 13 is 5-10mm.

In the embodiment, through 2

gaskets

12, 1

fin heat exchanger

11 and 2 partition plates, an air cavity 14 can be formed on two sides of the fin heat exchanger 11 respectively; the low-temperature medium is diffused to the first air cavity 14 after passing through the air hole 131 of one partition board, and the gas is uniformly distributed in the air cavity 14; the gas then uniformly flows through the heat exchange holes 115 of the fin heat exchanger 11 and exchanges heat with the fins 112; the low-temperature gas flows out of the fin heat exchanger 11 and then is collected in the second air cavity 14; the collected gas passes through the air holes 131 of the second separator and then enters the next group of heat exchange units.

The baffle 13 has the function of avoiding the formation of a local uneven area after the gas passes through the fin heat exchanger 11; the air holes 131 passing through the partition plate 13 are recombined, and the air can flow more disturbed by the throttling effect of the air holes, so that the heat transfer effect is improved.

As shown in fig. 4, the end members 3 at both ends of the superconducting motor rotor 2 comprise end flanges 31, the center of each end flange 31 is provided with a cooling pipe 32, each cooling pipe 32 is communicated with the air cavity 14 of the end gasket 12 of the heat exchanger structure 2, a sealing ring 33 is arranged between each end flange 31 and the end of the rotor, and a sealing cavity is formed by the through holes of each end flange 31 and each sealing ring 33; the heat exchanger structure 1 is assembled in the sealed cavity; the cooling pipe 32 is used for being connected with a low-temperature medium pipeline of an external low-temperature refrigeration system and is coaxially fixed on a central hole of the end flange 31 in a welding mode; the other end of the cooling tube 32 may be connected to an external cryogenic refrigeration system by welding, and the cryogenic medium is transferred to the sealed cavity, thereby cooling the heat exchanger structure 1.

The end flange 31 is made of stainless steel material and is of an annular structure; the superconducting motor rotor 2 is not connected with the superconducting motor rotor through bolts, and is sealed through the sealing ring 33, so that the central through hole in the superconducting motor rotor 2 is an independent cavity, namely, the low-temperature medium is prevented from leaking from the superconducting motor rotor 2; because the superconducting motor rotor 2 exists in a low-temperature environment, the sealing ring 33 is made of a low-temperature-resistant material, and in the embodiment, a metal sealing ring or a polytetrafluoroethylene sealing ring is selected; the end flange 31 can simultaneously fix the heat exchanger structure 1 axially in the central through-hole of the superconducting motor rotor 2.

The technical scheme of the invention is not limited to the embodiments, and all technical schemes obtained by adopting equivalent substitution modes fall within the scope of the invention.

Claims

1. The utility model provides a superconductive motor rotor heat exchanger structure, the rotor center is equipped with the through-hole, and heat exchanger structure sets up in the through-hole, its characterized in that: the heat exchanger structure comprises a plurality of heat exchanger units and a baffle plate, wherein the heat exchanger units are sequentially arranged along the axial direction of the through hole, the baffle plate is arranged between the adjacent heat exchanger units, and each heat exchanger unit comprises a fin heat exchanger and gaskets arranged on two sides of the fin heat exchanger; the outer diameters of the fin heat exchanger, the gasket and the partition plate are matched with the diameters of the through holes, a plurality of heat exchange holes which are uniformly distributed along the circumferential direction of the fin heat exchanger are formed in the fin heat exchanger, and the heat exchange Kong Jie is strip-shaped and is radially arranged along the fin heat exchanger; the gasket is annular, and a disc-shaped air cavity is formed in the inner side space of the gasket; an air hole is formed in the center of the partition plate; both ends of the heat exchange hole and the air hole are respectively communicated with the air cavities of the corresponding gaskets; end flanges are arranged at the two ends of the rotor, corresponding to the through holes, of the rotor, a cooling pipe is arranged in the center of each end flange, and the cooling pipe is communicated with an air cavity of an end gasket of the heat exchanger structure;

the part between the outer circumferential surface of the fin heat exchanger and one end, close to the outer diameter, of the plurality of heat exchange holes is an outer ring, the part between the center of the fin heat exchanger and one end, close to the center, of the plurality of heat exchange holes is an inner core, and the part between the inner core and the outer ring is divided into a plurality of fins by the plurality of heat exchange holes; the inner diameter of the gasket is matched with the inner diameter of the outer ring of the fin heat exchanger, and the diameter of the air hole is smaller than the diameter of the inner core of the fin heat exchanger;

the low-temperature medium is diffused to an adjacent air cavity after passing through the air hole of the partition plate, and the low-temperature medium is uniformly distributed in the air cavity, then uniformly flows through each heat exchange hole of the adjacent fin heat exchanger and exchanges heat with each fin; the low-temperature medium flows out of the fin heat exchanger and then is collected in the next air cavity, and the collected low-temperature medium enters the next heat exchanger unit after passing through the air holes of the next partition plate.

2. The superconducting motor rotor heat exchanger structure according to claim 1, wherein: the thickness of the fin heat exchanger is larger than that of the gasket, and the thickness of the gasket is larger than that of the partition plate.

3. The superconducting motor rotor heat exchanger structure according to claim 1, wherein: and a sealing ring is arranged between the end flange and the end of the rotor.