Water cooling motor and controller integrated water channel structure

Abstract

The invention discloses a water-cooled motor and controller integrated water channel structure, and relates to the technical field of motor water cooling, the water-cooled motor and controller integrated water channel structure comprises parallel double-helix water channels wound around a motor inner shell and a cooling water channel laid at the bottom of a controller shell, and the double-helix water channels are communicated with the cooling water channel; the water outlets and the water inlets of the two parallel double-helix water channels are arranged in a staggered mode, and the temperature gradient of water temperature in the water channels is reduced. The structure is provided with the two parallel spiral water channels, the same ends are respectively provided with the water inlet and the water outlet of the two parallel spiral water channels, and the overhigh temperature gradient at the two ends of the water-cooled motor can be compensated, so that the heat dissipation of the motor is more uniform, and the efficient and reliable operation of the motor is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of motor water cooling, and in particular to a water channel structure integrating a water-cooled motor and a controller. Background Art

[0002] A water-cooled motor is a device that uses a cooling water circulation system to cool the motor. It is mainly used for motors working in high-power, high-speed and high-temperature environments to reduce the temperature of the motor and improve its working efficiency and service life.

[0003] For water cooling of motors with a large axial length, the traditional water-cooled motor water channel will have a high temperature gradient between the water outlet and the water inlet (at both ends of the motor), which will damage the motor and reduce the service life of the motor. At present, with the miniaturization of motors, after the motor and the controller housing are integrated, the power semiconductor devices used in the controller (inverter) that controls the motor will also generate a lot of heat when the motor is running. If it is not dissipated in time, it may cause damage to the device. Therefore, it is particularly important to dissipate the heat of the controller; at the same time, the inlet and outlet of the traditional water-cooled motor water channel usually need to be arranged at both ends of the motor's axial direction, and the position on the radial section is also subject to certain restrictions. This is because the structural characteristics of the spiral water channel determine the flow direction and path of the fluid. If the position of the inlet and outlet is unreasonable, it may affect the circulation effect of the fluid and the heat dissipation performance of the motor. In some application scenarios with special requirements for the installation space and layout of the motor, the restricted arrangement of the inlet and outlet may bring certain difficulties to the design and installation of the motor.

[0004] For example: the invention application with application number 202010046924.0 discloses an electric water pump with an efficient heat dissipation and vibration reduction structure. The application scheme suppresses the heat load of the electric water pump through the coordination between the internal water cooling system, the structure on the motor stator that improves the heat dissipation of the coil, and the breathing system that exhales the hot air in the inner cavity and inhales the external cold air, greatly enhancing the heat dissipation efficiency and improving the high reliability of the operation of the electric water pump. Another example: the invention application with application number 202410704831.0 discloses a hybrid cooling structure of an outer rotor radial permanent magnet synchronous motor. The application scheme sends the fluid into each branch through the outer ring structure connecting the branches of the cooling pipe, flows through the inner diameter of the stator and gathers to the inner ring and is discharged through the water outlet, solving the problem that the outer rotor motor housing cannot be installed with a water cooling system and the motor cannot directly dissipate heat. The flow of the fluid is used to take away the heat and reduce the layer-by-layer transfer of heat.

[0005] Although the above scheme has made innovative improvements to the motor water cooling, there are also problems: 1. The temperature gradient between the outlet and the inlet of the cooling pipe is too high; 2. The motor controller is not cooled; 3. The layout of the inlet and outlet of the water channel is unreasonable; 4. The selection of the water channel cross section is not sufficiently considered. Summary of the invention

[0006] In view of the above-mentioned problems, the purpose of the present invention is to provide an integrated water channel structure of a water-cooled motor and a controller, reduce the temperature gradient between the water outlet and the water inlet, reasonably select the water channel cross-section, reasonably layout the water channel, and improve the heat dissipation performance of the water-cooled motor.

[0007] The object of the present invention can be achieved by the following technical solution: A water channel structure integrating a water-cooled motor and a controller, comprising:

[0008] A parallel double helix water channel wound around the inner shell of the motor, and a cooling water channel laid on the bottom of the controller shell, wherein the double helix water channel is connected to the cooling water channel;

[0009] Among them, the two water outlets and water inlets in the parallel double-helix water channel are staggered to reduce the temperature gradient of the water temperature in the water channel.

[0010] As a further solution of the present invention, the water-cooled motor housing is integrated with the controller housing.

[0011] As a further solution of the present invention, the cooling water channel is formed by a hollow groove in a cooling plate, and the cooling plate is closely attached to the bottom of the shell to take away the heat of the controller.

[0012] As a further solution of the present invention, the total water outlet pipe and the total water inlet pipe of the double helix water channel and the cooling water channel are connected to the inner groove of the cooling plate, and the openings of the total water outlet pipe and the total water inlet pipe are located on the side of the motor housing, perpendicular to the motor axis, and connected to the external pipeline.

[0013] As a further solution of the present invention, the empty groove structure in the cooling plate includes: a multi-S-bending groove and a U-shaped groove, the middle part of the multi-S-bending groove is connected to the main water inlet pipe, and the two ends of the multi-S-bending groove are respectively connected to the two water inlets of the double helix water channel; the two ends of the U-shaped groove are respectively connected to the two water outlets of the double helix water channel.

[0014] As a further solution of the present invention, the cross-sectional shape of the double helix water channel is circular, triangular or rectangular.

[0015] As a further solution of the present invention, the cross-sectional shape of the double helix water channel is selected according to the comprehensive heat exchange performance of the pipeline; the evaluation formula of the comprehensive heat exchange performance of the double helix water channel is:

[0016]

[0017] Wherein, Nu0 and f0 represent the Nusselt number and friction coefficient of circular pipes, respectively; Nu and f represent the Nusselt number and friction coefficient of pipes of other shapes, respectively;

[0018] The friction coefficient formula is expressed as:

[0019]

[0020] Among them, ΔP is the pressure drop, L is the length of the double helix water channel, and D h is the hydraulic diameter of the pipe, ρ is the density, and v0 is the flow velocity;

[0021] The Nusselt number formula is expressed as:

[0022]

[0023] Among them, S is the heat transfer area of ​​the contact surface, A is the total heat transfer surface area, q is the fluid heat flux density; λ is the thermal conductivity of the fluid.

[0024] As a further solution of the present invention, based on comprehensive heat exchange performance calculations, the cross-sectional shape of the double-helix water channel is preferably a rectangle.

[0025] As a further solution of the present invention, when the cross-sectional shape of the double helix water channel is a rectangle, the specific size of the rectangle is determined by a comprehensive analysis of the heat dissipation effect and the water resistance effect, wherein:

[0026] The heat dissipation effect analysis formula is:

[0027] Q=h×A×ΔT1

[0028] Where ΔT1 is the temperature difference between the liquid and the pipe wall, h is the convection heat transfer coefficient, and A is the total heat transfer surface area;

[0029] The water resistance effect analysis formula is:

[0030] ∑h f =h f +h′ f

[0031] Among them, h f is the resistance along the spiral waterway, h′ f is the local resistance of the spiral structure waterway;

[0032]

[0033] λ1 is the resistance coefficient along the way, L is the total length of the waterway, v is the flow velocity, g is the acceleration of gravity, and n is the number of turns of the waterway. The width of the water channel is a, the interval width between the water channels is m, and ζ is the local resistance coefficient.

[0034] Beneficial effects of the present invention:

[0035] 1. The structure of the present invention has two parallel spiral water channels, and two parallel spiral water channel inlets and outlets are arranged at the same end, which can compensate for the excessively high temperature gradient at both ends of the water-cooled motor, making the heat dissipation of the motor more uniform and ensuring efficient and reliable operation of the motor.

[0036] 2. The present invention also utilizes the water cooling system of the motor for the controller. The cooling water channel is laid on the bottom of the controller shell. The motor and the controller use the same water cooling system to dissipate heat, thereby improving heat dissipation efficiency and reducing occupied space.

[0037] 3. After the cooling water flows into the main water inlet of the present invention, it is divided to both ends through the multi-S bending grooves, and can fully contact the cooling plate to take away the heat absorbed by the cooling plate, thereby protecting the controller and increasing the service life of the controller.

[0038] 4. The water inlet and outlet of the present invention are led to one side of the integrated housing, which is convenient for connection with external pipelines and reduces the difficulty of layout of external pipelines.

[0039] 5. The present invention measures the comprehensive heat exchange performance of the pipeline and selects the cross-sectional shape of the double-helix water channel based on the comprehensive heat exchange performance of the pipeline, thereby making full use of the limited heat dissipation space inside the motor, improving the heat dissipation efficiency, and ensuring the smooth operation of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a schematic diagram of the integrated structure of the water-cooled motor and the controller of the present invention;

[0041] Figure 2 This is a schematic diagram of the horizontal double helix waterway structure of the present invention;

[0042] Figure 3 This is a schematic diagram of the double helix water channel and cooling plate structure of the present invention;

[0043] Figure 4 It is a schematic diagram of the double helix water channel and cooling water channel structure of the present invention;

[0044] Figure 5 This is a schematic diagram of the cooling water channel structure of the present invention;

[0045] Figure 6 It is a schematic diagram of the cross-sectional shape of the waterway of the present invention.

[0046] 110. Inner shell; 120. Double helix water channel; 121. Water channel space; 130. Cooling plate; 131. Multi-S bending groove; 132. U-shaped groove; 134. Plate cover; 135. Plate space; 140. Outer shell; 150. Controller; 160. Main water outlet pipe; 170. Main water inlet pipe. DETAILED DESCRIPTION

[0047] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar symbols throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0048] Existing water-cooled motors have problems such as too high temperature gradient between the water outlet and the water inlet of the cooling pipe, the motor controller 150 is not cooled, unreasonable layout of the water inlet and outlet of the water channel, and insufficient consideration in the selection of the water channel cross section.

[0049] In response to the above problems, Figure 1 As shown, the present invention discloses a water channel structure of an integrated water-cooled motor and controller, including a parallel double helix water channel 120 wound around the motor inner shell 110, the double helix water channel 120 is located in the water channel space 121 between the motor inner shell 110 and the motor outer shell; and a cooling water channel laid on the bottom of the controller 150 shell, the double helix water channel 120 is connected to the cooling water channel; wherein, the two water channel outlets and water inlets in the parallel double helix water channel 120 are staggered to reduce the temperature gradient of the water temperature in the water channel.

[0050] Through the above structure, such as Figure 2 As shown, the structure consists of two parallel spiral water channels, with two parallel spiral water channel inlets and outlets arranged at the same end. The excessive temperature gradient at both ends of the water-cooled motor can be compensated, making the heat dissipation of the motor more uniform and ensuring efficient and reliable operation of the motor.

[0051] Furthermore, with the demand for miniaturization of motors, the motor needs to be integrated with the controller 150 housing 140. The power semiconductor devices used in the motor controller 150 (inverter) will also generate a large amount of heat when the motor is running. If it is not dissipated in time, the device may be damaged.

[0052] Therefore, it is particularly important to dissipate heat for the controller 150. In view of this situation, the present invention also uses the water cooling system of the motor for the controller 150, such as Figure 3 As shown, the parallel double helix water channel 120 is wound between the motor inner shell 110 and the outer shell 140, and the heat exchange surface of the double helix water channel 120 is closely attached to the motor inner shell 110. The cooling water channel is laid on the bottom of the controller 150 shell, and the double helix water channel 120 is connected to the cooling water channel; the motor and the controller 150 use the same water cooling system to dissipate heat, improve heat dissipation efficiency, and reduce space occupation.

[0053] The cooling water channel is formed by the hollow groove in the cooling plate 130, and the hollow groove in the cooling plate 130 is sealed with the plate cover 134 to form the cooling water channel. The cooling plate 130 is located in the plate space 135 at the bottom of the controller 150 shell. The plate cover 134 of the cooling plate 130 is tightly attached to the bottom of the shell. The plate cover 134 and the bottom of the shell can be fixed by thermal conductive glue. The cooling plate 130 can be made of aluminum plate, which has low cost and good thermal conductivity. The heat of the controller 150 can be taken away through the cooling plate 130.

[0054] like Figure 4 and Figure 5 As shown, the empty groove structure in the cooling plate 130 includes a multi-S bending groove 131 and a U-shaped groove 132. The middle part of the multi-S bending groove 131 is connected to the main water inlet pipe 170, and the two ends of the multi-S bending groove 131 are respectively connected to the two water inlets of the double helix water channel 120, and the two ends of the U-shaped groove 132 are respectively connected to the two water outlets of the double helix water channel 120.

[0055] With the above structure, after the cooling water flows into the main water inlet, it is diverted to both ends through the multi-S bending groove 131, and can fully contact the cooling plate 130 to take away the heat absorbed by the cooling plate 130, thereby protecting the controller 150 and increasing the service life of the controller 150.

[0056] Furthermore, the water inlet and outlet of the water channel of the traditional water-cooled motor usually need to be arranged at both ends of the motor's axis, which will affect the circulation effect of the fluid and the heat dissipation performance of the motor. It also affects the motor installation space and layout, which is not conducive to the design and installation of the motor.

[0057] In view of the above situation, the double helix water channel 120 and the total water outlet pipe 160 and the total water inlet pipe 170 of the cooling water channel of the present invention are connected to the inner groove of the cooling plate 130, and the openings of the total water outlet pipe 160 and the total water inlet pipe 170 are located on the side of the motor housing 140, perpendicular to the motor axis, and connected to the external pipeline.

[0058] By adopting the above structure, the inlet and outlet water on both sides of the motor are introduced into one side of the motor integrated housing 140 through the heat dissipation water channel of the controller 150, which is convenient for connection with external pipelines and reduces the difficulty of layout of external pipelines.

[0059] Further, such as Figure 6 As shown, the cross-sectional shape of the double helix water channel 120 may be circular, triangular or rectangular; the cross-sectional shape of the double helix water channel 120 may be selected by measuring the comprehensive heat exchange performance of the pipeline and utilizing the comprehensive heat exchange performance of the pipeline.

[0060] Specifically, a pressure sensor and a temperature sensor are provided at the main water outlet pipe and the main water inlet pipe, and the pressure sensor and the temperature sensor are used to collect the total water inlet pressure P in , total water outlet P out , total inlet water temperature T in, average water temperature T out , and calculate the Nusselt number and friction coefficient of double helix water channels of various shapes, then measure the comprehensive heat transfer performance of the pipeline, and use the comprehensive heat transfer performance of the pipeline to select the cross-sectional shape of the double helix water channel.

[0061] The comprehensive heat transfer performance of the pipeline is as follows:

[0062]

[0063] Among them, Nu0 and f0 represent the Nusselt number and friction coefficient of the circular pipe respectively; Nu and f represent the Nusselt number and friction coefficient of pipes of other shapes respectively.

[0064] The friction coefficient formula is expressed as:

[0065]

[0066] Where ΔP is the pressure drop ΔP=P in -P out , L is the length of the double helix water channel, D h is the hydraulic diameter of the pipe; (S c is the cross-sectional area of ​​the flow channel; C is the circumference of the flow channel), ρ is the density, and v0 is the flow velocity.

[0067] The Nusselt number formula is expressed as:

[0068]

[0069] Where: S is the heat transfer area of ​​the contact surface, A is the total heat transfer surface area, q is the fluid heat flux density; λ is the thermal conductivity of the fluid.

[0070] After three measurements of various waterway cross-sectional shapes, the results are shown in Table 1:

[0071] Table 1 Comparison of comprehensive heat transfer performance of double helix water channel with different cross-sectional shapes

[0072]

[0073] It can be seen from Table 1 that in the case of limited space between the inner and outer shells of the motor, taking the circular pipe as the benchmark, comparing the triangular and rectangular shapes of the double helix water channel cross-section, the rectangular pipe has a higher comprehensive heat transfer performance index. Designing the water channel cross-section into a rectangular shape is the best choice, which can effectively utilize the space and improve the heat transfer performance.

[0074] Furthermore, when the cross-sectional shape of the double helix water channel is a rectangle, the specific length and width of the rectangle can be determined by comprehensive analysis of the heat dissipation effect and the water resistance effect:

[0075] For heat dissipation effect analysis, the formula is expressed as:

[0076] Q=h×A×ΔT1

[0077] Among them, ΔT1 is the temperature difference between the liquid and the pipe wall, h is the convection heat transfer coefficient, and A is the total heat transfer surface area.

[0078] Taking the rectangular water channel as an example, let the water channel width be a, the water channel height be b, the interval width between water channels be m, and L be the axial length of the motor. Then the total heat exchange surface area A is expressed as:

[0079]

[0080] In engineering, b = m is generally taken, that is,

[0081] A=2πDL

[0082] The convective heat transfer coefficient h is expressed as:

[0083]

[0084] Where Nu is the Nusselt number, de is the equivalent diameter of the pipe, that is, λ is the thermal conductivity of the fluid, and the Nusselt number Nu can be expressed as

[0085]

[0086] Re is the Reynolds number, Pr is the Blount number of the fluid, Prf is the Blount constant at the water temperature, and Prw is the Blount constant at the wall temperature. Prw and Prf are close to being equal. The Reynolds number Re can be expressed as:

[0087]

[0088] v is the liquid flow velocity, q is the liquid flow rate, and τ is the liquid kinematic viscosity coefficient:

[0089]

[0090] μ is the dynamic viscosity, ρ is the liquid density, and the fluid Bronte number Pr can be expressed as:

[0091]

[0092] Where c is the specific heat capacity of the liquid.

[0093] In summary, the convective heat transfer coefficient can be expressed as

[0094]

[0095] For the same motor size, when the fluid and flow rate are determined, the convection heat transfer coefficient is related to the water channel width a and the water channel height b.

[0096] According to the heat dissipation effect analysis formula:

[0097] Q=h×A×ΔT1

[0098] At this time, the temperature difference between the liquid and the pipe wall is ΔT1, the total heat exchange surface area A is constant, and the heat dissipation effect depends on the convection heat transfer coefficient h. It can be seen that for the same circumference, the smaller a and b are, the better.

[0099] a and b are not equal. The rectangular water channel has better heat dissipation effect than the square water channel. Considering the equivalent diameter de, for the same cross-sectional area, the larger the perimeter, the smaller de, and theoretically the better the heat dissipation effect. The square water channel has the worst heat dissipation.

[0100] The water resistance effect is analyzed and the formula is expressed as:

[0101] ∑h f =h f +h′ f

[0102] The waterway of the spiral structure is divided into the resistance along the way h f , local resistance h′ f .

[0103]

[0104] Among them, λ1 is the resistance coefficient along the way, λ1 is related to the Reynolds number Re, L is the total length of the waterway, v is the flow velocity, g is the gravitational acceleration, and n is the number of turns of the waterway. ζ is the local resistance coefficient; the Re values ​​are shown in Table 2:

[0105] Table 2 Comparison of Re values ​​and cross-sectional dimensions:

[0106] Re 2320 3160 <![CDATA[10 5 ]]> <![CDATA[10 6 ]]> a+b / mm 190 139.5 4.4 0.44

[0107] At 3160 <Re<10 5 Reasonable, at this time

[0108]

[0109] The resistance along the way can be expressed as:

[0110]

[0111] The local drag coefficient can be expressed as:

[0112]

[0113] R is the radius of the circle, and θ is 2π around one circle:

[0114]

[0115] Therefore, ∑hf It can be calculated. It can be seen that for the same perimeter, the larger a and b are, the better. If a and b are not equal, the water resistance of a rectangular waterway is larger than that of a square. Considering the equivalent diameter de, for the same cross-sectional area, the larger the perimeter, the smaller de, and theoretically the larger the water resistance, the square waterway has the smallest water resistance.

[0116] The pump power can be expressed as:

[0117]

[0118] q is the pump flow rate, h1 is the pump head, and η is the pump efficiency, which is taken as 70%.

[0119] For example: the motor diameter D = 316mm; the motor axial length L = 150mm; the fluid is a 50% ethylene glycol mixture, at 70°C, the parameter values ​​are shown in Table 3.

[0120] Table 3 Fluid parameter values

[0121] Dynamic viscosity μ / Pa·s <![CDATA[Density ρ / kg / m 3 > Specific heat capacity ρ / J (kg·℃) <![CDATA[Thermal conductivity λ / W / (m 2 ·°C)]]> <![CDATA[1.17×10 -3 ]]> 1045.49 3474 0.408

[0122] Cooling water flow rate q = 15L / min

[0123] Kinematic viscosity coefficient

[0124] Blount number

[0125] Calculate four groups of water channels, the values ​​are shown in Table 1:

[0126] Table 4 Comparison of parameters and dimensions of rectangular cross-sections of waterways

[0127]

[0128] It can be seen that the heat dissipation effect and the water resistance effect (i.e. the required water pump power) cannot be achieved at the same time. The appropriate rectangular cross-section water channel can be selected according to the actual heat dissipation and water resistance requirements.

[0129] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

[0130] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

Claims

1. A water channel structure integrating a water-cooled motor and a controller, characterized in that: include: A parallel double helix water channel (120) wound around the motor inner shell (110), and a cooling water channel laid on the bottom of the controller (150) shell, wherein the double helix water channel (120) is connected to the cooling water channel; The water outlets and water inlets of the two water channels in the parallel double-helix water channel (120) are arranged alternately, thereby reducing the temperature gradient of the water temperature in the water channel.

2. The waterway structure according to claim 1, characterized in that: The water-cooled motor housing (140) and the controller (150) housing (140) are integrated into one body.

3. The waterway structure according to claim 2, characterized in that: The cooling water channel is formed by a hollow groove in a cooling plate (130), and the cooling plate (130) is closely attached to the bottom of the shell to take away the heat of the controller (150).

4. The waterway structure according to claim 2, characterized in that: The total water outlet pipe (160) and the total water inlet pipe (170) of the double helix water channel (120) and the cooling water channel are connected to the inner groove of the cooling plate (130); the openings of the total water outlet pipe (160) and the total water inlet pipe (170) are located on the side of the motor housing (140), perpendicular to the motor axis, and connected to external pipelines.

5. The waterway structure according to claim 4, characterized in that: The hollow groove structure inside the cooling plate (130) comprises: a multi-S bending groove (131) and a U-shaped groove (132); the middle of the multi-S bending groove (131) is connected to the main water inlet pipe (170); the two ends of the multi-S bending groove (131) are respectively connected to the two water inlets of the double helix water channel (120); and the two ends of the U-shaped groove (132) are respectively connected to the two water outlets of the double helix water channel (120).

6. The water channel structure according to claim 5, characterized in that: The cross-sectional shape of the double helix water channel (120) is circular, triangular or rectangular.

7. The waterway structure according to claim 6, characterized in that: The cross-sectional shape of the double helix water channel is selected according to the comprehensive heat transfer performance of the pipeline; the evaluation formula for the comprehensive heat transfer performance of the double helix water channel is: Wherein, Nu0 and f0 represent the Nusselt number and friction coefficient of circular pipes, respectively; Nu and f represent the Nusselt number and friction coefficient of pipes of other shapes, respectively; The friction coefficient formula is expressed as: Among them, ΔP is the pressure drop, L is the length of the double helix water channel, and D h is the hydraulic diameter of the pipe, ρ is the density, and v0 is the flow velocity; The Nusselt number formula is expressed as: Among them, S is the heat transfer area of ​​the contact surface, A is the total heat transfer surface area, q is the fluid heat flux density; λ is the thermal conductivity of the fluid.

8. The waterway structure according to claim 7, characterized in that: According to comprehensive heat exchange performance calculations, the cross-sectional shape of the double-helix water channel is preferably a rectangle.

9. The water channel structure according to claim 8, characterized in that: When the cross-sectional shape of the double helix water channel is a rectangle, the specific size of the rectangle is determined by comprehensive analysis of the heat dissipation effect and the water resistance effect, wherein: The heat dissipation effect analysis formula is: Q=h×A×ΔT1 Where ΔT1 is the temperature difference between the liquid and the pipe wall, h is the convection heat transfer coefficient, and A is the total heat transfer surface area; The water resistance effect analysis formula is: ∑h f =h f +h′ f Among them, h f is the resistance along the spiral waterway, h′ f is the local resistance of the spiral structure waterway; λ1 is the resistance coefficient along the way, L is the total length of the waterway, v is the flow velocity, g is the acceleration of gravity, and n is the number of turns of the waterway. The width of the water channel is a, the interval width between the water channels is m, and ζ is the local resistance coefficient.

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