Cooling flow channel structure and motor

Abstract

The invention discloses a cooling flow channel and a motor, the cooling flow channel structure comprises a shell and a plurality of pairs of supporting sheets, the shell is provided with an inlet, an outlet and a cooling flow channel communicating the inlet and the outlet, and the cooling flow channel extends along the length direction of the shell; the supporting pieces are arranged in the cooling flow channel and connected with the lower bottom face and the upper top face of the cooling flow channel, the multiple pairs of supporting pieces are arranged in the length direction of the shell at equal intervals, each pair of supporting pieces are arranged in a splayed shape and form a near end and a far end, the distance between the two supporting pieces at the near ends is smaller than the distance between the two supporting pieces at the far ends, and the near ends face the inlet. The motor comprises a cooling flow channel structure and a stator winding, and the cooling flow channel structure is attached to the stator winding. Compared with the prior art, the cooling flow channel structure provided by the invention can enhance the heat exchange coefficient by 15%-20% under the working condition of low flow velocity (Reynolds number is less than 4000) of cooling oil compared with a conventional structure without a supporting sheet, so that the heat exchange performance of the motor is enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of motor heat dissipation, and in particular to a cooling channel structure and a motor. Background Art

[0002] In some motors, such as high-temperature superconducting motors, due to the magnetic saturation of iron teeth caused by excessively high magnetic fields, the stator adopts an air-gap armature structure with composite teeth. However, this structure will affect the original conventional cooling methods, such as air cooling, water jacket cooling, etc., so the existing motors use transformer oil cooling.

[0003] The existing cooling channel design scheme consists of a composite sealing cylinder and its components that structurally form a closed annular area that surrounds the entire stator coil. The transformer oil enters from one side of the closed annular area, flows through the axially arranged air gap armature stator cooling channel in the core segment coil, and flows out from the other side of the closed annular area, taking away the stator heat loss, and then enters the closed area again after being cooled in an external oil-water heat exchanger to form a cooling cycle.

[0004] Most of the heat of the stator coil is conducted out through the wall of the cooling channel and then taken away by the cooling oil. The designed flow rate of the cooling oil distributed to the cooling channel is low. The cooling channel originally used for the oil-cooled air-gap armature stator is a simple pipe structure. According to the Reynolds number formula Re=ρvd / υ, the Reynolds number is in the range of 200 to 1000. Under this Reynolds number (laminar flow), the heat transfer coefficient is low and the heat transfer effect is poor. Summary of the invention

[0005] The purpose of the present invention is to overcome the above technical deficiencies, propose a cooling channel structure and a motor, and solve the technical problem in the prior art that the cooling channel has poor heat exchange effect at low Reynolds numbers.

[0006] In order to achieve the above technical objectives, the present invention adopts the following technical solutions: In a first aspect, the present invention provides a cooling channel structure, comprising: an outer shell, the outer shell being formed with an inlet and an outlet and a cooling channel connecting the inlet and the outlet, the cooling channel extending along the length direction of the outer shell; and a plurality of pairs of support plates, the support plates being arranged in the cooling channel and connected to the lower bottom surface and the upper top surface of the cooling channel, the plurality of pairs of support plates being arranged at equal intervals along the length direction of the outer shell, each pair of support plates being arranged in an "eight" shape and forming a proximal end and a distal end, the spacing between the two support plates at the proximal end being smaller than the spacing at the distal end, and the proximal end facing the inlet.

[0007] In some embodiments, the housing includes a cover plate and a bottom plate portion, the cover plate is welded to the bottom plate portion, the bottom plate portion and the support piece are integrally formed, and the support piece abuts against the cover plate.

[0008] In some embodiments, the cross-section of the support sheet is rectangular or trapezoidal, and the thickness of the support sheet is less than 1 mm.

[0009] In some embodiments, the included angle between the support plate and the extension direction of the cooling channel is 45°.

[0010] In some embodiments, the support piece height is H and the support piece length is 4H.

[0011] In some embodiments, the distance between two adjacent groups of support plates is less than 6H, and the width of the cooling channel is 10-15H.

[0012] In some embodiments, the distance between two support sheets in the same group at the proximal end is 3H.

[0013] In a second aspect, the present invention further provides a motor, comprising a cooling channel structure and a stator winding, wherein the cooling channel structure is arranged close to the stator winding.

[0014] In some embodiments, an iron core is further included, and the cooling channel structure is located within the extension range of the iron core.

[0015] In some embodiments, a sealing cylinder is also included, in which the cooling channel structure, the stator winding and the iron core are arranged. The sealing cylinder has an oil inlet formed at one end facing the inlet and an oil inlet formed at one end facing the outlet.

[0016] Compared with the prior art, the cooling channel structure provided by the present invention can enhance the heat transfer coefficient by 15% to 20% under the condition of low cooling oil flow rate (Reynolds number less than 4000) compared with the conventional structure without support plates, thereby enhancing the heat transfer performance of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic structural diagram of a cooling channel structure provided by an embodiment of the present invention; Figure 2 is a schematic diagram of the internal structure of the cooling channel structure provided by an embodiment of the present invention; Figure 3 is an internal front view of a cooling channel structure provided by an embodiment of the present invention; Figure 4 A schematic diagram of the internal structure of a motor provided by an embodiment of the invention; Figure 5 A cross-sectional view of a motor provided according to an embodiment of the invention. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0019] In order to solve the technical problem that the conventional flow channel has poor heat exchange effect under low Reynolds number, the present invention provides a cooling flow channel structure that can achieve more efficient heat exchange.

[0020] It should be noted that the cooling channel structure described in the present invention is used for but not limited to motors. For the sake of convenience, in the present invention, only the cooling channel structure applied to motors is used as an example for explanation. The principles of applying the cooling channel structure to other types of equipment are essentially the same as those applied to motors, and will not be repeated here.

[0021] See also Figures 1 to 3 The cooling channel structure includes: a shell 1 and a plurality of pairs of support sheets 2.

[0022] The housing 1 is formed with an inlet and an outlet and a cooling channel connecting the inlet and the outlet, and the cooling channel extends along the length direction of the housing. The support sheet 2 is arranged in the cooling channel and connected to the lower bottom surface and the upper top surface of the cooling channel, and is used to divide and disturb the cooling oil when the cooling oil flows through the cooling channel. Multiple pairs of support sheets 2 are arranged at equal intervals along the length direction of the housing 1, and each pair of support sheets 2 is arranged in an "eight" shape and forms a proximal end and a distal end. The spacing between the two support sheets 2 at the proximal end is smaller than the spacing at the distal end, and the proximal end faces the inlet.

[0023] Under low Reynolds number conditions, the cooling oil in the existing cooling channel flows mainly in laminar flow, and only the momentum exchange caused by the molecular thermal motion occurs between adjacent fluid layers. This forms a temperature gradient where the temperature gradually decreases from the near side to the far side of the heat dissipated object, i.e., the stator winding. This results in the highest temperature of the cooling oil closest to the stator winding, which reduces the heat exchange efficiency.

[0024] The cooling channel mechanism is based on the vortex generator principle to set the support plate 2. When the cooling oil flows through the support plate 2, the longitudinal vortex destroys the growth of the boundary layer, increases the turbulence intensity, and generates a secondary fluid flow on the heat transfer surface, thereby improving the heat exchange performance.

[0025] In some embodiments, the housing 1 includes a cover plate 11 and a bottom plate 12, the cover plate 11 and the bottom plate 12 are welded and connected, and the bottom plate 12 and the support sheet 2 are integrally formed, such as by using 3D printing technology. When the cover plate 11 is welded to the bottom plate 12, the support sheet 2 abuts against the cover plate 11.

[0026] In this embodiment, the applicant obtains the dimensionless index R reflecting the heat exchange effect through theoretical calculation as follows: (1) (2) (3) (4) (5) (6) In formula (1), the larger the dimensionless index R is, the better the heat transfer effect is. h is the convective heat transfer coefficient, D is the hydraulic diameter, λ is the thermal conductivity, ρ is the density, U represents the flow rate, μ represents the dynamic viscosity, and c is p represents the specific heat at constant pressure, and Δp represents the pressure drop.

[0027] Compared with the conventional flow channel, the pressure drop Δp of the present cooling flow channel is larger, and the f0 calculated according to formula (3) is larger, which makes f / f0 smaller, thereby increasing the dimensionless index R. That is, the heat exchange effect of the present cooling flow channel is better than that of the conventional flow channel.

[0028] The applicant also calculated through simulation that: under the actual working condition of low Reynolds number (200-1000), the cross section of the support plate 2 is rectangular or trapezoidal, the thickness of the support plate 2 is less than 1mm, and the angle α between the support plate 2 and the extension direction of the cooling channel is 45°. The height of the support plate 2 is H, and the length of the support plate 2 c is 4H. The distance d between two adjacent groups of support plates 2 is less than 6H, and the width L of the cooling channel is 10-15H. The spacing b between the two support plates 2 in the same group at the proximal end is 3H. When this design is adopted, the cooling channel structure can obtain the highest heat exchange efficiency.

[0029] In one embodiment, see Figure 4 and Figure 5 The motor includes a cooling channel structure 3 and a stator winding 4. The cooling channel structure 3 is arranged close to the stator winding 4 to absorb the heat generated when the stator winding 4 is working. The stator winding 4 adopts an air gap armature stator structure.

[0030] In some embodiments, the motor also includes an iron core 5, and the cooling channel structure 3 is located within the extension range of the iron core 5, that is, the cooling channel mechanism 3 is arranged parallel to the iron core 5, and the two ends of the cooling channel mechanism are located on the inner side of the two ends of the iron core 5 and do not extend outside the iron core 5.

[0031] In some embodiments, the motor further comprises a sealing cylinder 6, and the cooling channel structure 3, the stator winding 4 and the iron core 5 are arranged in the sealing cylinder 6. The sealing cylinder 6 is formed with an oil inlet at one end facing the inlet, and the sealing cylinder 6 is formed with an oil inlet at one end facing the outlet. The cooling oil flows in from the oil inlet, flows out from the oil outlet, and then is cooled by an external heat dissipation device. The cooling channel structure 3, the stator winding 4 and the iron core 5 are immersed in the cooling oil. While the cooling oil performs basic heat dissipation on the cooling channel structure 3, the stator winding 4 and the iron core 5, it also flows into the cooling channel structure to dissipate heat for the stator winding 4 in a targeted manner, so as to avoid the stator winding 4 located inside from being overheated due to poor heat dissipation.

[0032] The specific implementation of the present invention described above does not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A cooling channel structure, characterized in that: include: A shell, wherein the shell is formed with an inlet and an outlet and a cooling channel connecting the inlet and the outlet, and the cooling channel extends along the length direction of the shell; as well as A plurality of pairs of support plates are provided in the cooling channel and connected to the lower bottom surface and the upper top surface of the cooling channel. The plurality of pairs of support plates are arranged at equal intervals along the length direction of the shell. Each pair of support plates is arranged in an "eight" shape and forms a proximal end and a distal end. The distance between two support plates at the proximal end is smaller than the distance at the distal end, and the proximal end faces the inlet.

2. The cooling channel structure according to claim 1, characterized in that: The housing comprises a cover plate and a bottom plate portion, the cover plate is welded to the bottom plate portion, the bottom plate portion is integrally formed with the support piece, and the support piece abuts against the cover plate.

3. The cooling channel structure according to claim 1, characterized in that: The cross section of the support sheet is rectangular or trapezoidal, and the thickness of the support sheet is less than 1 mm.

4. The cooling channel structure according to claim 1, characterized in that: The included angle between the support plate and the extending direction of the cooling channel is 45°.

5. The cooling channel structure according to claim 1, characterized in that: The support piece has a height of H and a length of 4H.

6. The cooling channel structure according to claim 5, characterized in that: The distance between two adjacent groups of the support plates is less than 6H, and the width of the cooling channel is 10-15H.

7. The cooling channel structure according to claim 5, characterized in that: The distance between the two supporting plates in the same group at the proximal end is 3H.

8. A motor, characterized in that: It comprises a cooling channel structure as described in any one of claims 1 to 7 and a stator winding, wherein the cooling channel structure is arranged close to the stator winding.

9. The motor according to claim 8, characterized in that It also includes an iron core, and the cooling channel structure is located within the extension range of the iron core.

10. The motor according to claim 8, characterized in that It also includes a sealing cylinder, in which the cooling channel structure, the stator winding and the iron core are arranged. The sealing cylinder is formed with an oil inlet at one end facing the inlet, and the sealing cylinder is formed with an oil inlet at one end facing the outlet.

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