Cooling channel structure and motor

Abstract

The application discloses a cooling flow channel and a motor. The cooling flow channel structure comprises a shell and multiple pairs of supporting plates. The shell is formed with an inlet, an outlet and a cooling flow channel connecting the inlet and the outlet. The cooling flow channel extends along the length direction of the shell. The supporting plates are arranged in the cooling flow channel and connected with the lower bottom surface and the upper top surface of the cooling flow channel. The multiple pairs of supporting plates are arranged at equal intervals along the length direction of the shell. Each pair of supporting plates is arranged in an "eight" shape and forms a proximal end and a distal end. The interval of the two supporting plates at the proximal end is smaller than that at the distal end. The proximal end faces the inlet. The motor comprises the cooling flow channel structure and a stator winding. The cooling flow channel structure is arranged close to the stator winding. Compared with the prior art, the cooling flow channel structure provided by the application can enhance the heat exchange coefficient by 15%-20% under the working condition of low flow rate (Reynolds number less than 4000) of cooling oil compared with the conventional structure without the supporting plates, thereby enhancing the heat exchange performance of the motor.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of motor heat dissipation, in particular to a cooling flow channel structure and motor. BACKGROUND

[0002] In some motors, such as high-temperature superconducting motors, due to the magnetic saturation of the iron teeth caused by the excessively high magnetic field, the stator adopts an air gap armature structure with a tooth part made of a composite material. However, this structure will affect the original conventional cooling methods, such as air cooling and water jacket cooling. Therefore, the existing motor adopts a transformer oil cooling scheme.

[0003] The existing cooling flow channel design scheme forms a closed annular area from the structure of the composite material sealing cylinder and its components, which surrounds the entire stator coil. The transformer oil enters from one side of the closed annular area, flows through the axial air gap armature stator cooling flow channel in the core section coil to the other side of the closed annular area, and then flows out, thereby taking away the heat loss of the stator. Subsequently, after being cooled in an external oil-water heat exchanger, the transformer oil reenters the closed area to form a cooling cycle.

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

[0005] The present application aims to overcome the above technical deficiencies and provides a cooling flow channel structure and motor to solve the technical problem of poor heat exchange effect of the cooling flow channel under low Reynolds number in the prior art.

[0006] To achieve the above technical purpose, the present application adopts the following technical scheme:

[0007] In a first aspect, the present application provides a cooling flow channel structure, comprising: an outer shell, the outer shell being formed with an inlet and an outlet and a cooling flow channel communicating the inlet and the outlet, the cooling flow channel extending along the length direction of the outer shell; and a plurality of pairs of supporting sheets, the supporting sheets being arranged in the cooling flow channel and connected with the lower bottom surface and the upper top surface of the cooling flow channel, the plurality of pairs of supporting sheets being arranged at equal intervals along the length direction of the outer shell, each pair of supporting sheets being arranged in an "eight" shape and forming a proximal end and a distal end, the distance between the two supporting sheets at the proximal end being smaller than the distance between the two supporting sheets at the distal end, and the proximal end facing the inlet.

[0008] In some embodiments, the outer shell includes a cover plate and a bottom plate portion, the cover plate being weldedly connected with the bottom plate portion, the bottom plate portion being integrally formed with the supporting sheets, and the supporting sheets abutting against the cover plate.

[0009] In some embodiments, the cross section of the strut is rectangular or trapezoidal, and the thickness of the strut is less than 1mm.

[0010] In some embodiments, the angle between the strut and the extension direction of the cooling flow channel is 45°.

[0011] In some embodiments, the height of the strut is H, and the length of the strut is 4H.

[0012] In some embodiments, the distance between two adjacent groups of struts is less than 6H, and the width of the cooling flow channel is 10-15H.

[0013] In some embodiments, the distance between two struts in the same group at the proximal end is 3H.

[0014] In the second aspect, the application further provides an electric machine, comprising a cooling flow channel structure and a stator winding, wherein the cooling flow channel structure is arranged against the stator winding.

[0015] In some embodiments, the application further comprises an iron core, and the cooling flow channel structure is located within the extension range of the iron core.

[0016] In some embodiments, the application further comprises a sealing cylinder, and the cooling flow channel structure, the stator winding and the iron core are arranged in the sealing cylinder, wherein an oil inlet is formed at one end of the sealing cylinder facing the inlet, and an oil outlet is formed at one end of the sealing cylinder facing the outlet.

[0017] Compared with the prior art, the cooling flow channel structure provided by the application can enhance the heat exchange coefficient by 15%-20% under the working condition of low flow rate of cooling oil (Reynolds number less than 4000) compared with the conventional structure without struts, thereby enhancing the heat exchange performance of the electric machine. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a structural schematic diagram of the cooling flow channel structure provided by the embodiment of the application;

[0019] Figure 2 is a structural schematic diagram of the cooling flow channel structure provided by the embodiment of the application;

[0020] Figure 3 is an internal front view of the cooling flow channel structure provided by the embodiment of the application;

[0021] Figure 4 is an internal structural schematic diagram of the electric machine provided by the embodiment of the application;

[0022] Figure 5 is a sectional view of the electric machine provided by the embodiment of the application. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below with reference to the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application and not to limit the present application.

[0024] In order to solve the technical problem that the conventional flow channel has poor heat exchange effect at low Reynolds number, the present application provides a cooling flow channel structure which can realize more efficient heat exchange.

[0025] It should be noted that the cooling flow channel structure described in the present application is used for but not limited to a motor. In order to facilitate the description, in the present application, only the cooling flow channel structure applied to the motor is taken as an example for description, and the principle of the cooling flow channel structure applied to other types of equipment is substantially the same as that applied to the motor, which is not described here.

[0026] Please refer to Figures 1 to 3 , the cooling flow channel structure comprises an outer shell 1 and a plurality of pairs of supporting plates 2.

[0027] The outer shell 1 is formed with an inlet and 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 outer shell. The supporting plate 2 is arranged in the cooling flow channel and connected with the lower bottom surface and the upper top surface of the cooling flow channel, and is used for dividing and disturbing the cooling oil when the cooling oil flows through the cooling flow channel. The plurality of pairs of supporting plates 2 are arranged at equal intervals along the length direction of the outer shell 1, each pair of supporting plates 2 is arranged in an "eight" shape, and forms a proximal end and a distal end, and the interval of the two supporting plates 2 at the proximal end is smaller than that at the distal end, and the proximal end faces the inlet.

[0028] In the case of low Reynolds number, the cooling oil in the existing cooling flow channel mainly flows in the form of laminar flow when flowing, and only the momentum exchange caused by molecular thermal motion exists between adjacent fluid layers. A temperature gradient is formed from the stator winding, i.e. the heat dissipation object, to the distal end, and the temperature gradually decreases. The temperature of the cooling oil closest to the stator winding is the highest, which reduces the heat exchange efficiency.

[0029] And the cooling flow channel mechanism sets the supporting plate 2 based on the principle of vortex generator. When the cooling oil flows through the supporting plate 2, the heat exchange performance is improved based on the mechanism of destroying the boundary layer growth, increasing the turbulence intensity and generating secondary fluid flow on the heat transfer surface.

[0030] In some embodiments, the outer shell 1 comprises a cover plate 11 and a bottom plate part 12, the cover plate 11 is welded to the bottom plate part 12, and the bottom plate part 12 is integrally formed with the supporting plate 2, which can be produced by using 3D printing technology. When the cover plate 11 is welded to the bottom plate part 12, the supporting plate 2 abuts against the cover plate 11.

[0031] In the present embodiment, the applicant obtains the formula of the dimensionless index R reflecting the heat exchange effect through theoretical calculation as follows:

[0032] (1)

[0033] (2)

[0034] (3)

[0035] (4)

[0036] (5)

[0037] (6)

[0038] In formula (1), the larger the dimensionless index R is, the better the heat exchange 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 velocity, μ represents the dynamic viscosity, c p represents the specific heat at constant pressure, and Δp represents the pressure drop.

[0039] The pressure drop Δp of the cooling flow channel is larger than that of the conventional flow channel, f0 calculated according to formula (3) is larger, so that f / f0 is smaller, thereby increasing the dimensionless index R. That is, the heat exchange effect of the cooling flow channel is better than that of the conventional flow channel.

[0040] The applicant also obtains through simulation calculation that, in the actual working condition of low Reynolds number (200-1000), the cross section of the support piece 2 is rectangular or trapezoidal, the thickness of the support piece 2 is less than 1 mm, and the angle α between the support piece 2 and the extension direction of the cooling flow channel is 45°. The height of the support piece 2 is H, and the length c of the support piece 2 is 4H. The distance d between the two adjacent groups of support pieces 2 is less than 6H, and the width L of the cooling flow channel is 10-15H. The spacing b between the two support pieces 2 in the same group at the proximal end is 3H. When this design is adopted, the cooling flow channel structure can obtain the highest heat exchange efficiency.

[0041] In one of the embodiments, referring to Figure 4 and Figure 5 , the motor includes the cooling flow channel structure 3 and the stator winding 4, the cooling flow channel structure 3 is arranged close to the stator winding 4 to absorb the heat generated by the stator winding 4 during operation. The stator winding 4 adopts an air gap armature stator structure.

[0042] In some embodiments, the motor also includes the iron core 5, the cooling flow channel structure 3 is located within the extension range of the iron core 5, that is, the cooling flow channel structure 3 is arranged parallel to the iron core 5, and both ends of the cooling flow channel structure are located inside both ends of the iron core 5 and do not extend outside the iron core 5.

[0043] In some embodiments, the motor further comprises a sealed cylinder 6, the cooling flow channel structure 3, the stator winding 4 and the iron core 5 are arranged in the sealed cylinder 6, the sealed cylinder 6 is formed with an oil inlet at one end towards the inlet, and the sealed cylinder 6 is formed with an oil outlet at one end towards the outlet. Cooling oil flows into the oil inlet and then flows out of the oil outlet, and then is cooled by an externally connected heat dissipation device. The cooling flow channel structure 3, the stator winding 4 and the iron core 5 are immersed in the cooling oil, and the cooling oil not only conducts basic heat dissipation to the cooling flow channel structure 3, the stator winding 4 and the iron core 5, but also flows into the cooling flow channel structure to conduct targeted heat dissipation to the stator winding 4, so as to avoid the temperature of the stator winding 4 inside being too high due to poor heat dissipation.

[0044] The above description of the specific embodiments of the present application does not constitute a limitation on the scope of protection of the present application. Any other corresponding changes and modifications made according to the technical concept of the present application shall be included in the scope of protection of the claims of the present application.

Claims

1. A cooling runner structure, characterized by, The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding.

2. The cooling runner structure according to claim 1, characterized by The application relates to a cooling flow channel structure of a stator winding.

3. The cooling runner structure according to claim 1, characterized by The application relates to a cooling flow channel structure of a stator winding.

4. The cooling runner structure according to claim 1, characterized by The application relates to a cooling flow channel structure of a stator winding.

5. The cooling runner structure according to claim 1, characterized by The application relates to a cooling flow channel structure of a stator winding.

6. The cooling runner structure according to claim 5, characterized by The application relates to a cooling flow channel structure of a stator winding.

7. The cooling runner structure according to claim 5, wherein The application relates to a cooling flow channel structure of a stator winding.

8. An electric machine characterized by The application relates to a cooling flow channel structure of a stator winding.

9. The electric machine of claim 8, wherein, The application relates to a cooling flow channel structure of a stator winding.

10. The electric machine of claim 8, wherein, The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator winding. The application relates to a cooling flow channel structure of a stator

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