A water-cooling plate structure for high-power-density power electronic device cooling and a design method thereof based on simp topology optimization

Abstract

A water-cooled plate structure for cooling high-power-density power electronic devices and its design method based on SIMP topology optimization are disclosed. The structure includes a water-cooled plate body with an inlet, an outlet, and a flow channel region. The flow channel region includes an inlet guiding region and a parallel flow channel region. The inlet guiding region contains several double-elliptical guiding structures arranged in a needle-fin array. The parallel flow channel region consists of several dispersed independent flow channels, each corresponding to a heat source region of a chip. This invention, through the coordinated design of the inlet guiding region and the parallel flow channel region, achieves efficient heat dissipation and good temperature uniformity while ensuring low flow resistance, meeting the heat dissipation requirements of high-power electronic devices.

Description

Technical Field

[0001] This invention relates to the field of heat dissipation technology for electronic devices, specifically to a water-cooled plate structure for cooling high-power-density power electronic devices and its design method based on SIMP topology optimization. Background Technology

[0002] As power electronics technology advances towards higher power density and higher frequency, the heat flux density of semiconductor power electronic devices is increasing dramatically. Heat dissipation and cooling have become a significant bottleneck restricting system performance, reliability, and lifespan. Particularly in fields such as new energy vehicles, high-end servers, and aerospace, SiC MOSFETs, as core switching devices, while possessing excellent high-temperature and high-frequency characteristics, can suffer from concentrated high heat loads if these loads are not dissipated promptly and effectively. This can cause the chip junction temperature to rapidly exceed the safety threshold, leading to performance degradation and even permanent failure.

[0003] Among numerous heat dissipation technologies, liquid cooling has become the preferred solution for handling high heat loads due to its high specific heat capacity and excellent heat transfer efficiency. The core of a liquid-cooled radiator lies in its internal flow channel structure design, which directly determines two key indicators: heat exchange performance and flow performance. Traditional water-cooled plates for cooling power devices often employ cylindrical needle-fin arrays or parallel flow channel structures, which suffer from problems such as high flow resistance, uneven temperature distribution, and low heat dissipation efficiency.

[0004] Topology optimization methods automatically allocate material density through mathematical optimization, finding structural shapes with minimum flow resistance and optimal heat transfer performance under certain constraints, without relying on human experience. Domestic and international scholars have applied it to various scenarios such as battery thermal management and chip cooling channel structure design, demonstrating its significant advantages in reducing temperature, improving temperature uniformity, and reducing pump power. However, applying topology optimization to the design of SiC MOSFET power module liquid coolers still faces specific challenges: it requires constructing an accurate thermal-fluid-solid multiphysics coupling model, while simultaneously addressing the heat dissipation requirements of high heat flux density dispersing multiple chip heat sources and the energy-saving requirements of low flow resistance.

[0005] Therefore, this invention proposes a technical solution to address the shortcomings of existing water-cooled plate structures for cooling high-power-density power devices in terms of heat exchange efficiency, flow resistance, and temperature uniformity. Summary of the Invention

[0006] In view of the shortcomings of the existing technology, one of the objectives of this invention is to provide a water-cooled plate for cooling high power density power electronic devices. The aim is to achieve the technical effect of efficient heat dissipation and good temperature uniformity while ensuring low flow resistance through the coordinated design of the inlet guide area and the parallel flow channel area, so as to meet the heat dissipation requirements of high power electronic devices.

[0007] The second objective of this invention is to provide a design method based on SIMP topology optimization, which is intended for designing this water-cooled plate structure.

[0008] One of the objectives of this invention is achieved through the following technical solution: A water-cooled plate for cooling high-power-density power electronic devices includes a water-cooled plate structure body, on which a liquid inlet, a liquid outlet, and a flow channel region are provided. The liquid inlet and outlet are used for the inflow and outflow of coolant, respectively. The flow channel region includes an inlet guiding area and a parallel flow channel region. The inlet guiding area has several double-elliptical guiding structures arranged in a needle-fin array, which are used to reduce flow resistance at the inlet and promote uniform distribution of downstream fluid. The parallel flow channel region consists of several dispersed independent flow channels, each corresponding to a heat source region of a chip, for achieving parallel fluid flow.

[0009] Preferably, the parameters of the double elliptical guiding structure are: the length of the minor axis is 0.7-0.9 mm, the length of the major axis is 1.3-1.4 mm, the translation distance between the two ellipses is 2.23-2.27 mm, and the length of the chamfer radius at the intersection of the two ellipses is 1 mm.

[0010] Preferably, the wall of the independent flow channel is designed with a micro-fold structure to enhance flow disturbance and heat exchange effect.

[0011] The second objective of this invention is achieved by the following technical solution: A design method based on SIMP topology optimization, used to design the water-cooled plate structure body as described in any one of claims 1-3, characterized by comprising the following steps: Step 1: Determine the design parameters of the topology optimization region based on the heat source size and heat dissipation area, and establish the geometric model of the water-cooled plate in conjunction with the double elliptical guiding structure; Step two: Set the physical properties of the working fluid and solid within the water-cooled plate, as well as the unique thermal conductivity of the interpolation material; Step 3: Establish a calculation model of the flow field and temperature field within the water-cooled plate, set relevant boundary conditions and initial values, and add multiphysics fields for non-isothermal flow; Step 4: Establish grid cell division; Step 5: Based on the variable density model of topology optimization, set up five specific steps: filtering, projection, interpolation, discretization, and initial values. Step 6: Establish the topology optimization solver, and set the optimization solution method, optimization tolerance, optimization objective function, and solver constraints. Step 7: Filter to obtain the topology.

[0012] Preferably, in step three, when establishing the temperature field calculation model, the applied heat source boundary condition is a non-uniform temperature field based on the actual application scenario of SiCMOSFET.

[0013] Preferably, the thermal conductivity of the interpolation material in step two is denoted as k. θ ,k θ The expression is: Where, k s k is the thermal conductivity of a solid. f θ is the thermal conductivity of the fluid, θ is the density variable, and p1 is the interpolation coefficient.

[0014] Preferably, the solver for topology optimization in step six is ​​Snopt, and the optimization tolerance is set to 1×10. -8 The objective function is obj; the constraint is that the fluid domain accounts for 45%-50%.

[0015] Preferably, obj is a weighted sum of the two objectives of flow and heat transfer, and its expression is: Where w1 is the weighting coefficient for heat transfer, w2 is the weighting coefficient for flow, and j th0 Let j be the normalized objective function for heat transfer. f0 The normalized objective function for the flow; j th0 The expression is: Where, j th The objective function for heat transfer is expressed as follows: j f0 The expression is: Where, j f The objective function for flow is expressed as follows: .

[0016] Compared with the prior art, the significant advantages of this invention are: 1. High-efficiency heat dissipation performance: Through the flow channel structure generated by topology optimization, the temperature of each heat source can be reduced by up to about 10.3 ℃ compared with the traditional circular needle fin array structure under the same pump power.

[0017] 2. Low flow resistance: The optimized flow channel layout significantly reduces pressure drop, with a pressure drop of only 7.3 kPa at a flow velocity of 0.6 m / s, which is about 45% lower than that of the traditional circular needle fin array structure.

[0018] 3. Excellent temperature uniformity: The parallel flow channel design can significantly reduce local heat accumulation, and the maximum temperature difference between heat sources #1 and #3 can be as low as 1.6 ℃.

[0019] 4. Process feasibility: The flow channel width is not less than 0.6 mm, and there are no fins on the edge, which meets the processing and manufacturing requirements.

[0020] 5. High adaptability: The proposed design method can be adapted to different heat dissipation scenarios for power electronic devices by adjusting the heat source layout and power. Attached Figure Description

[0021] Figure 1 This is a two-dimensional vector graphic of Comparison Example 1; Figure 2 This is a schematic diagram of the structure in Comparative Example 1; Figure 3 This is a two-dimensional vector image of Example 1; Figure 4 This is a schematic diagram of the structure of Embodiment 1.

[0022] Reference numerals: 1. Liquid inlet; 2. Liquid outlet; 3. Double elliptical guide structure. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Example 1: A water-cooled plate for cooling high-power-density power electronic devices includes a water-cooled plate structure body. The water-cooled plate structure body has a liquid inlet, a liquid outlet, and a flow channel region. The flow channel region includes an inlet guide area and a parallel flow channel region. The inlet guide area has several double-elliptical guide structures arranged in a needle-fin array. The parallel flow channel region consists of several dispersed independent flow channels. Each of the dispersed independent flow channels corresponds to a heat source region of a chip. The walls of the independent flow channels are designed with a micro-folded structure. The design parameters of the double-elliptical guide structure are: the minor axis of the ellipse is 0.8 mm, the major axis of the ellipse is 1.35 mm, the translational distance between the two ellipses is 2.25 mm, and a chamfer with a radius of 1 mm is taken at the intersection of the two ellipses.

[0025] A design method based on SIMP topology optimization, the specific operation steps of which are as follows: Step one: Determine the design parameters of the topology optimization design region based on the heat source size and heat dissipation area. Then, establish the geometric model of the water-cooled plate by combining the double elliptical guiding structure.

[0026] Step 2: Set the physical properties of the working fluid and solid within the water-cooled plate, as well as the thermal conductivity of the interpolation material. The thermal conductivity of the interpolation material is denoted as k. θ ,k θ The expression is: Where, k s k is the thermal conductivity of a solid. f θ is the thermal conductivity of the fluid, θ is the density variable, and p1 is the interpolation coefficient.

[0027] Step 3: Establish the flow field calculation model of the water-cooled plate, set the relevant boundary conditions and initial values, and its governing equations are expressed as: Where ρ is the fluid density, u is the velocity vector, I is the impulse vector, K is the viscosity dissipation term of the flow field, and F is the volume force term affected by the design density.

[0028] When setting the volume force F, it is expressed as: Where α is the flow resistance coefficient.

[0029] Simultaneously, a temperature field calculation model for the water-cooled plate is established, and relevant boundary conditions and initial values ​​are set. Its governing equation is expressed as: Where dz is the model thickness and q is the thermal conductivity term, its expression is: In equation (10), Q is the heat source term, and its expression is: Where Te represents a more realistic non-uniform temperature field, its expression is: The expression for T_Qi_j is shown in Table 2.

[0030] Table 2. Expressions for the temperature of non-uniform heat sources Subsequently, a multiphysics field for non-isothermal flow was added.

[0031] Step 4: Establish a detailed mesh cell division, with a mesh cell size of 0.2 mm, a maximum cell growth rate of 1.13, a curvature factor of 0.3, and a narrow region resolution of 1 for a free triangular mesh, with a total number of cells of 24 W.

[0032] Step 5: Establish a variable density model for topology optimization, setting up five specific steps: filtering, projection, interpolation, discretization, and initial values. Specifically, the filter type is Helmholtz, with a filter radius of 0.3 mm; the projection type is hyperbolic tangent projection, with a projection slope of 84 and a projection point of 0.5; the interpolation type is Darcy interpolation, with the Darcy penalty function being a constant of 0.05; linear discretization is used for the control unit; and the initial value of the control variable is set to 0.5.

[0033] Step 6: Establish the topology optimization solver, setting the optimization method and tolerance, as well as the objective function and constraints. The topology optimization solver uses SNOPT (SparseNonlinear OPTimizer), with an optimization tolerance of 1×10⁻⁸; the objective function is obj; and the constraint is that the fluid domain occupies 45%-50%. Here, obj is the weighted sum of the flow and heat transfer objectives, expressed as: Where w1 is the weighting coefficient for heat transfer, w2 is the weighting coefficient for flow, and j th0 Let j be the normalized objective function for heat transfer. f0 The normalized objective function for the flow; j th0 The expression is: Where, j th The objective function for heat transfer is expressed as follows: j f0 The expression is: Where, j f The objective function for flow is expressed as follows: Step 7: Set the topology optimization threshold θ=0.5, filter the topology configuration, and create mesh parts and geometric models based on the filtering results, finally generating a 2D vector diagram, as shown below. Figure 3 As shown.

[0034] Step 8: Extrude the 2D drawing into a 3D geometric model to obtain the final water-cooled plate structure, as shown below. Figure 4 As shown.

[0035] Example 2: The difference from Embodiment 1 is that the design parameters of the double elliptical guide structure are different. In Embodiment 2, the design parameters of the double elliptical guide structure are: the minor axis of the ellipse is 0.7 mm, the major axis of the ellipse is 1.3 mm, the translation distance between the two ellipses is 2.23 mm, and a chamfer with a radius of 1 mm is taken at the intersection of the two ellipses.

[0036] Example 3: The difference from Embodiment 1 is that the design parameters of the double elliptical guide structure are different. In Embodiment 3, the design parameters of the double elliptical guide structure are: the minor axis of the ellipse is 0.9 mm, the major axis of the ellipse is 1.4 mm, the translation distance between the two ellipses is 2.27 mm, and a chamfer with a radius of 1 mm is taken at the intersection of the two ellipses.

[0037] Comparative Example 1: The difference from Example 1 is that, as Figure 1 and Figure 2 As shown, no double-elliptical guide structure is provided in the inlet guide area of ​​the water-cooled plate structure. When establishing the geometric model of the water-cooled plate, the design parameters of the topology optimization design area are determined only based on the heat source size and heat dissipation area, without incorporating the double-elliptical guide structure.

[0038] Comparative Example 2: The conventional water-cooled plate with a cylindrical needle-fin array structure is a well-known existing technology in the art. Therefore, the specific structure and design method of Comparative Example 2 will not be described in detail.

[0039] Performance testing: 1. Under a pressure drop of 14.27 kPa, the highest temperature distributions of Examples 1, 2, 3, Comparative Example 1, and Comparative Example 2 under the same heat load were compared, and the results are shown in the bar chart. Figure 1 As shown.

[0040] columnar Figure 1 The highest temperatures of Comparative Example 1, Example 1, Example 2, and Example 3 were all significantly lower than those of Comparative Example 2, demonstrating superior heat dissipation performance. Among them, Comparative Example 1 exhibited the most uniform temperature distribution among the heat sources, with a maximum temperature difference of only 1.6 ℃, and its #3 heat source temperature was 10.3 ℃ lower than that of Comparative Example 2; while Example 1 showed the most significant cooling effect at heat source #1, which was 7.9 ℃ lower than that of Comparative Example 2; the cooling effects of Examples 2 and 3 at each heat source were not as good as those of Example 1.

[0041] 2. Under the condition of a fixed inlet flow velocity of 0.6 m / s, the pressure drop values ​​of Comparative Example 1, Comparative Example 2, Example 1, Example 2, and Example 3 were compared. The comparison results are shown in the bar chart. Figure 2 As shown.

[0042] columnar Figure 2 The pressure drop in Comparative Example 2 was 12.98 kPa, while the pressure drops in Comparative Example 1 and Example 1 were only 10.19 kPa and 7.30 kPa, respectively. This indicates that the two proposed structures significantly improve flow resistance and greatly enhance fluid throughput. The pressure drop effects in Examples 2 and 3 were not as good as those in Example 1.

[0043] The water-cooled plate structure generated by the topology optimization method in this invention achieves a reasonable balance between efficient heat dissipation and low flow resistance, with good temperature uniformity and process feasibility, and can be widely used in the field of thermal management of power electronic devices.

[0044] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "top / bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. In addition, the terms "second" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0045] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "sleeved / connected," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0046] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0047] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A water-cooled plate for cooling high-power-density power electronic devices, comprising a water-cooled plate structure body, characterized in that... The water-cooled plate structure body is provided with a liquid inlet, a liquid outlet and a flow channel area. The flow channel area includes an inlet guide area and a parallel flow channel area. The inlet guide area is provided with a number of double elliptical guide structures in the form of a needle fin array. The parallel flow channel area is composed of a number of dispersed independent flow channels, and the number of dispersed independent flow channels respectively correspond to a number of chip heat source areas.

2. The water-cooled plate for cooling high-power-density power electronic devices as described in claim 1, characterized in that... The parameters of the double elliptical guiding structure are as follows: the length of the minor axis is 0.7-0.9 mm, the length of the major axis is 1.3-1.4 mm, the translation distance between the two ellipses is 2.23-2.27 mm, and the length of the chamfer radius at the intersection of the two ellipses is 1 mm.

3. The water-cooled plate for cooling high-power-density power electronic devices as described in claim 1, characterized in that... The walls of the independent flow channel are designed with a micro-fold structure.

4. A design method based on SIMP topology optimization, used to design the water-cooled plate structure body as described in any one of claims 1-3, characterized in that... This includes the following steps: Step 1: Determine the design parameters of the topology optimization region based on the heat source size and heat dissipation area, and establish the geometric model of the water-cooled plate in conjunction with the double elliptical guiding structure; Step two: Set the physical properties of the working fluid and solid within the water-cooled plate, as well as the unique thermal conductivity of the interpolation material; Step 3: Establish a calculation model of the flow field and temperature field within the water-cooled plate, set relevant boundary conditions and initial values, and add multiphysics fields for non-isothermal flow; Step 4: Establish grid cell division; Step 5: Based on the variable density model of topology optimization, set up five specific steps: filtering, projection, interpolation, discretization, and initial values. Step 6: Establish the topology optimization solver, and set the optimization solution method, optimization tolerance, optimization objective function, and solver constraints. Step 7: Filter to obtain the topology.

5. The design method based on SIMP topology optimization according to claim 4, characterized in that... In step three, when establishing the temperature field calculation model, the applied heat source boundary condition is a non-uniform temperature field based on the actual application scenario of SiC MOSFET.

6. The design method based on SIMP topology optimization according to claim 4, characterized in that... The thermal conductivity of the interpolation material in step two is denoted as k. θ ,k θ The expression is: Where, k s k is the thermal conductivity of a solid. f θ is the thermal conductivity of the fluid, θ is the density variable, and p1 is the interpolation coefficient.

7. The design method based on SIMP topology optimization according to claim 1, characterized in that... In step six, the topology optimization solver uses SNOPT, with an optimization tolerance set to 1×10⁻⁶. -8 The objective function is obj; the constraint is that the fluid domain accounts for 45%-50%.

8. The design method based on SIMP topology optimization according to claim 4, characterized in that... ,obj is the weighted sum of the two objectives of flow and heat transfer, and its expression is: Where w1 is the weighting coefficient for heat transfer, w2 is the weighting coefficient for flow, and j th0 Let j be the normalized objective function for heat transfer. f0 The normalized objective function for the flow; j th0 The expression is: Where, j th The objective function for heat transfer is expressed as follows: j f0 The expression is: Where, j f The objective function for flow is expressed as follows: 。

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