An EGR cooler cooling structure arrangement design method and an EGR cooler

Abstract

The application discloses a kind of EGR cooler cooling structure arrangement design method and its EGR cooler, including the design of matrix type pipeline arrangement structure and the design of heat dissipation pattern, the design of matrix type pipeline arrangement structure includes overall arrangement area comprehensive heat exchange area calculation, the required single pipe quantity is calculated, the shell inner diameter D is calculated and the tube distance is determined, the design of heat dissipation pattern includes the arrangement rule of determining pattern type and outer surface and inner surface, and pattern type is any one in pit array, wave pattern or diamond pattern structure.The pipeline design of square section is adopted in the application, has greater surface area, helps to improve heat exchange efficiency, and compared with traditional finned cooler, has lower gas side pressure loss, pits are opened in the inner wall of pipeline, increase the turbulence degree of fluid, break the fluid boundary layer, improve heat transfer effect, can effectively improve the engine EGR rate, so as to improve the engine thermal efficiency, while to a certain extent reduce the risk of cooler carbon deposition, guarantee the continuous operation of engine.

Description

Technical Field

[0001] This invention belongs to the field of EGR cooler technology, specifically relating to an EGR cooler cooling structure layout design method and an EGR cooler thereof. Background Technology

[0002] In the current field of hybrid passenger vehicle engines, EGR systems have become standard equipment. Most existing EGR systems use finned coolers, which effectively reduce combustion temperature and nitrogen oxide emissions by introducing some exhaust gas into the intake system. At the same time, they optimize the engine combustion process, improve fuel economy and power performance, and play a key role in engine emissions and performance.

[0003] With increasingly stringent environmental regulations and stricter requirements for engine emissions, coupled with rising consumer expectations for engine performance, EGR cooler performance has become a key factor determining overall engine efficiency. Currently, the redevelopment and application of EGR coolers face numerous challenges, requiring compliance with factors such as high heat transfer performance, low pressure loss, resistance to carbon buildup, corrosion resistance, compact design and lightweight construction, structural reliability, and cost control. The current mainstream finned flat-tube EGR coolers are insufficient for all application scenarios, necessitating the introduction of more advanced solutions. Summary of the Invention

[0004] This invention addresses the problems of high gas-side pressure loss, small liquid contact area, insufficient compactness, and poor reliability in existing finned EGR coolers. It adopts a square cross-section pipe design, which has a larger surface area than a circular pipe, thus improving heat exchange efficiency. Recesses are created on the inner wall of the pipe to increase fluid turbulence, break the fluid boundary layer, and enhance heat transfer, effectively increasing the engine's EGR rate and thus improving engine thermal efficiency. Compared to traditional finned coolers, it has lower gas-side pressure loss and reduces the risk of carbon buildup in the cooler. It also eliminates the need for frequent cleaning, effectively reducing maintenance costs and downtime, and ensuring continuous engine operation.

[0005] The technical problem solved by this invention can be achieved by the following technical solution: a cooling structure layout design method for an EGR cooler, including the design of a matrix pipe layout structure and the design of a heat dissipation pattern, characterized in that:

[0006] The design of a matrix-style piping layout includes the following steps:

[0007] A1. Calculation of the overall heat transfer area based on the heat transfer rate equation. Calculate the required heat exchange area A, where Q is the heat transfer volume, K is the overall heat transfer coefficient, and ΔT is the total heat transfer area. lm The logarithmic mean temperature difference;

[0008] A2. Calculate the required number of single tubes N. Where A0 is the heat exchange area of ​​a single tube;

[0009] A3. Calculate the inner diameter D of the shell when using a single-pass tube. When using multi-pass, Where t is the tube center distance, n c The number of tubes crossing the centerline of the tube bundle, k is a coefficient, and d o Where η is the outer diameter of the tube and η is the tube sheet utilization rate.

[0010] A4. Determine the pipe spacing;

[0011] The design of the heat dissipation pattern includes the following steps:

[0012] S1. Determine the pattern type, which can be any one of the following: pit array, wave pattern, or diamond pattern structure;

[0013] S2. Determine the arrangement rules for the inner and outer surfaces;

[0014] The design device for implementing the matrix-style pipeline layout structure design and heat dissipation pattern design includes:

[0015] EGR cooler model drawing module: used to create the model of the EGR cooler and determine the layout range of the matrix piping based on the size of the EGR cooler;

[0016] The parameter setting module for the EGR cooler is used to set parameters such as inlet air temperature, inlet air flow rate, inlet air pressure, inlet liquid temperature, and inlet liquid flow rate.

[0017] The parameter calculation module for the matrix piping is used to calculate various parameters of the matrix piping and heat dissipation pattern based on the parameters set in the parameter setting module of the EGR cooler mentioned above.

[0018] The matrix piping synthesis module is used to synthesize the various parameters of the matrix piping obtained from the above matrix piping parameter calculation module with the EGR cooler model drawn in the EGR cooler model drawing module to obtain an EGR cooler containing matrix piping.

[0019] The parameter testing module for EGR coolers is used to obtain various performance indicators of the EGR cooler based on the matrix piping synthesis module obtained above, through three-dimensional simulation or actual testing.

[0020] In step A4, the pipe spacing is 1-2 mm.

[0021] In step S1, the pit array has a depth of 0.1-0.3 mm and a diameter of 1-2 mm; the wave pattern has an amplitude of 0.15-0.25 mm and a wavelength of 3-5 mm; the diamond pattern has a height of 0.5-1 mm and a spacing of 2-3 mm.

[0022] In step S2, the inner surface adopts a 35-55° oblique cross pattern, and the outer surface adopts a radial protrusion array.

[0023] The bottom length of the matrix-type pipeline is L1, and the distance from the bottom of the matrix-type pipeline to the protrusion in the outer surface protrusion array is L2. .

[0024] The porosity factor F of the matrix-type pipeline ranges from 0.6 to F < 0.9, where... Where A1 is the surface area of ​​the outer surface of all heat exchange tubes in the matrix pipeline, and A2 is the surface area of ​​the protrusions in the protrusion array of the outer surface of all heat exchange tubes in the matrix pipeline.

[0025] The matrix-type pipeline layout can adopt a regular or irregular structure. When a regular structure is adopted, it includes a first regular area with a rectangular cross-section, and several heat exchange tubes fill the first regular area.

[0026] When the matrix-type pipeline layout adopts an irregular structure, it also includes an irregular region, which includes a second regular region and an irregular region. The cross-section of the second regular region is the rectangle with the largest area in the irregular region, and several heat exchange tubes fill the second regular region.

[0027] The first and second rule areas adopt a matrix-style pipeline layout and a heat dissipation pattern design.

[0028] An EGR cooler employs the aforementioned EGR cooler cooling structure layout design method.

[0029] Compared with existing technologies, this invention has the following advantages: Addressing the problems of high gas-side pressure loss, small liquid contact area, insufficient compactness, and poor reliability in existing finned EGR coolers, this invention adopts a square cross-section pipe design. Compared to circular pipes, square pipes have a larger surface area, which helps improve heat exchange efficiency. Compared to traditional finned coolers, it has lower gas-side pressure loss. The recessed pits on the inner wall of the pipe increase fluid turbulence, break the fluid boundary layer, and improve heat transfer, effectively increasing the engine's EGR rate and thus improving engine thermal efficiency. Simultaneously, it reduces the risk of carbon buildup in the cooler to some extent, eliminating the need for frequent cleaning, effectively reducing maintenance costs and downtime, and ensuring continuous engine operation. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of the present invention;

[0031] Figure 2 This is a cross-sectional view of the present invention;

[0032] Figure 3 This is a schematic diagram of a matrix-style pipeline layout using a regular structure.

[0033] Figure 4 This is a schematic diagram of a matrix-style pipeline layout using an irregular structure.

[0034] Figure 5 This is a side view of a matrix-style piping system;

[0035] Figure 6 This is the equivalent plastic strain diagram of the present invention;

[0036] Figure 7 yes Figure 6 The equivalent plastic strain value parameter diagram in the figure;

[0037] Figure 8 This is the thermal strain diagram when the output variable of this invention is NT11;

[0038] Figure 9 yes Figure 8 The thermal strain diagram parameter diagram;

[0039] Figure 10 This is the equivalent plastic strain diagram of a finned EGR cooler;

[0040] Figure 11 yes Figure 10 The equivalent plastic strain value parameter diagram in the figure;

[0041] Figure 12 This is a thermal strain diagram of a finned EGR cooler with an output variable of NT11.

[0042] Figure 13 yes Figure 12 The thermal strain diagram parameter diagram;

[0043] Figure 14 This is the gas-side velocity contour plot of the heat exchanger tube in Example 1;

[0044] Figure 15 This is the gas-side pipeline mass flow diagram of Analysis Example 1;

[0045] Figure 16 This is the gas-side mass flow rate deviation diagram of Analysis Example 1;

[0046] Figure 17 This is the airside streamline distribution diagram of Analysis Example 1;

[0047] Figure 18 This is the air-side pressure distribution diagram of Analysis Example 1;

[0048] Figure 19 This is the heat exchanger tube temperature contour plot of Analysis Example 1;

[0049] Figure 20 This is the velocity contour plot of the heat exchanger tube in Example 2;

[0050] Figure 21 This is the pipeline mass flow diagram from Example 2;

[0051] Figure 22 This is the mass flow rate deviation diagram for Example 2;

[0052] Figure 23 This is the air-side streamline distribution diagram of Example 2;

[0053] Figure 24 This is the air-side pressure distribution diagram of Example 2;

[0054] Figure 25 This is the heat exchanger tube temperature contour plot of Example 2;

[0055] In the diagram: 1-Air inlet, 2-Exhaust outlet, 3-Coolant inlet, 4-Coolant outlet, 5-First regular zone, 6-Second regular zone, 7-Irregular zone. Detailed Implementation

[0056] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below with reference to specific illustrations.

[0057] In the description of this invention, it should be understood that the terms "one end", "the other end", "outer side", "upper", "inner side", "horizontal", "coaxial", "center", "end", "length", "outer end", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0058] Example 1

[0059] Combined with appendix Figures 1 to 25 As shown, this embodiment discloses a cooling structure layout design method for an EGR cooler, including the design of a matrix pipe layout structure and the design of a heat dissipation pattern, wherein:

[0060] The design of a matrix-style piping layout includes the following steps:

[0061] A1. Calculation of the overall heat transfer area based on the heat transfer rate equation. Calculate the required heat exchange area A (unit: m²) 2Where Q is the amount of heat transferred (in W), and K is the overall heat transfer coefficient (in W). ), ΔT lm The logarithmic mean temperature difference (unit: K);

[0062] A2. Calculate the required number of single tubes N. Where A0 is the heat exchange area of ​​a single tube (unit: m²) 2 The specifications are determined by the heat exchange tubes.

[0063] A3. Calculate the inner diameter D of the shell (unit: mm) when using a single-pass tube. When using multi-pass, Where t is the tube center distance (unit: mm), n c The number of tubes crossing the centerline of the tube bundle, k is a coefficient (dimensionless, 2~3), d o Where η is the outer diameter of the tube (unit: mm), and η is the tube sheet utilization rate (dimensionless).

[0064] A4. Determine the pipe spacing, using 1-2mm based on empirical values;

[0065] The design of the heat dissipation pattern includes the following steps:

[0066] S1. Determine the pattern type, which can be any one of the following: pit array, wave pattern, or diamond pattern structure;

[0067] S2. Determine the arrangement rules for the inner and outer surfaces.

[0068] The design device for implementing the matrix-style pipeline layout structure design and heat dissipation pattern design includes:

[0069] EGR cooler model drawing module: used to create the model of the EGR cooler and determine the layout range of the matrix piping based on the size of the EGR cooler;

[0070] The parameter setting module for the EGR cooler is used to set parameters such as inlet air temperature, inlet air flow rate, inlet air pressure, inlet liquid temperature, and inlet liquid flow rate.

[0071] The parameter calculation module for the matrix piping is used to calculate various parameters of the matrix piping and heat dissipation pattern based on the parameters set in the parameter setting module of the EGR cooler mentioned above.

[0072] The matrix piping synthesis module is used to synthesize the various parameters of the matrix piping obtained from the above matrix piping parameter calculation module with the EGR cooler model drawn in the EGR cooler model drawing module to obtain an EGR cooler containing matrix piping.

[0073] The parameter testing module for EGR coolers is used to obtain various performance indicators of the EGR cooler based on the matrix piping synthesis module obtained above, through three-dimensional simulation or actual testing.

[0074] In combination with the above, in step S1, the pit array has a depth of 0.1-0.3 mm and a diameter of 1-2 mm, which is used to disrupt the boundary layer and induce eddies; the wave pattern has an amplitude of 0.15-0.25 mm and a wavelength of 3-5 mm, which is used to extend the flow path and enhance turbulence; the diamond pattern structure has a height of 0.5-1 mm and a spacing of 2-3 mm, which is used to expand the heat exchange area by more than 30%.

[0075] In combination with the above, in step S2, the inner surface uses a 35-55° oblique cross pattern to reduce flow resistance, and the outer surface uses a radial array of protrusions to enhance the gas-side heat exchange effect.

[0076] Based on the above, the bottom length of the matrix-type pipeline is L1, and the distance from the bottom of the matrix-type pipeline to the protrusion in the outer surface protrusion array is L2. The porosity factor F of the matrix-type pipeline ranges from 0.6 to F < 0.9, where... Where A1 is the surface area of ​​the outer surface of all heat exchange tubes in the matrix pipeline, and A2 is the surface area of ​​the protrusions in the protrusion array of the outer surface of all heat exchange tubes in the matrix pipeline.

[0077] In summary, the matrix piping layout can adopt either a regular or irregular structure. When a regular structure is adopted, it includes a first regular area 5, which has a rectangular cross-section and is filled with several heat exchange tubes. When the matrix piping layout adopts an irregular structure, it also includes an irregular area, which includes a second regular area 6 and an irregular area 7. The second regular area 6 has a rectangular cross-section with the largest area among the irregular areas and is filled with several heat exchange tubes. The cooling structure arrangement of the first regular area 5 and the second regular area 6 adopts the design method of steps A1-A4, S1 and S2 described above, making the overall design more compact.

[0078] Based on the above, pressure loss along the friction path (Unit: Pa), where λ is the friction pressure loss coefficient (dimensionless, depends on Reynolds number and pipe wall roughness), L is the length of the straight pipe section (unit: m), and ρ is the fluid density inside the pipe (unit: kg / m³). 3 v is the average flow velocity of the fluid in the pipe (unit: m / s).

[0079] In conjunction with the above, to further illustrate the comparative technical effects of this invention with existing technologies of the same type, existing technical software such as Abaqus or ANSYS was used for structural analysis and thermal stress analysis; existing technical software such as Unigraphics NX or Creo was used for three-dimensional structural design and surface area calculation; and existing technical software such as Ansys Fluent was used for CFD analysis, heat transfer performance analysis, and pressure loss analysis, with the same boundary conditions set. Specifically, the ambient temperature was set to 31.1℃, the inlet temperature to 435℃, the inlet flow rate to 28.5 kg / h, the absolute inlet pressure to 103.2 kPa, the liquid inlet temperature to 100℃, and the liquid inlet flow rate to 12 L / min. The performance comparison results of this embodiment with existing finned EGR coolers are as follows: the gas pressure loss in this embodiment is 1.4 kPa, while that of the finned EGR cooler is 1.6 kPa, representing a 12.5% ​​reduction in gas pressure loss; when using 15 heat exchange tubes on the liquid side, the surface area is 70948.05 mm². 2 When 18 heat exchange tubes are used, the liquid side surface area is 85137.66 mm². 2 Compared to finned EGR coolers, which are 52853mm², 2 The liquid-side surface area increased by 34% and 61% respectively; combined with the attached Figure 6-13 As shown, the maximum thermal stress strain in this embodiment is 5576µε, while that of the finned EGR cooler is 16510µε, a reduction of 66%; the overall heat transfer coefficient K in this embodiment is 210. The finned EGR cooler is 120. The improvement is 75%; the anti-carbon deposition cycle in this embodiment is 800h, and the finned EGR cooler is 300h, which is 167% improvement.

[0080] In light of the above, to further illustrate the computational effectiveness of the present invention under different influent flow rates, sub-analysis examples with an influent pressure of 130 kPa and influent flow rates of 12 L / min and 25 L / min were used as Analysis Example 1 and Analysis Example 2, respectively. The analysis results and performance test data are as follows:

[0081] Table 1. Heat transfer performance test results

[0082] Analysis example one Analysis of Example 2 Inlet temperature / °C 435 435 Exhaust port temperature / °C 116.9 115.0 Coolant inlet temperature / °C 100 100 Coolant outlet temperature / °C 103.45 101.7 Heat exchange / kW 2.6 2.6 Heat exchange efficiency / % 95.0 95.5

[0083] As shown in Table 1, the exhaust port 2 temperatures of Analytical Example 1 and Analytical Example 2 were 116.9℃ and 115℃, respectively, both less than 120℃, and the heat exchange efficiencies were 95.0% and 95.5%, respectively. They have the characteristics of strong heat exchange performance and high heat exchange efficiency, which can significantly improve the ability to resist carbon deposits.

[0084] Combined with appendix Figure 14-17 As shown in Figures 20-23, the appendix is... Figure 14 and attached Figure 20 The figures show the gas-side velocity contour maps of the heat exchanger tubes in Examples 1 and 2, respectively. The color distribution of the gas velocity in the figures represents the magnitude of the gas-side velocity (unit: m / s) along the heat exchanger tube profile. (Attached) Figure 15 and attached Figure 21 The figures show the gas-side pipeline mass flow rates for Analysis Examples 1 and 2, respectively. The horizontal axis represents the heat exchange tube number, and the vertical axis represents the gas-side pipeline mass flow rate (unit: kg / s). (See attached figures.) Figure 16 and attached Figure 22 The graphs show the gas-side mass flow rate deviations for Analysis Examples 1 and 2, respectively. The horizontal axis represents the heat exchanger tube number, and the vertical axis represents the gas-side mass flow rate deviation (unit: %). (See attached graph.) Figure 17 and attached Figure 23 The images show the air-side streamline diagrams for Analysis Example 1 and Analysis Example 2, respectively. The colored streamline diagrams in the figures represent the velocity magnitude (unit: m / s) of the airflow path. Based on the maximum deviation... Total deviation M i For individual values, M avg M is the average value. total Given the sum, analyze the maximum flow deviation D between Example 1 and Example 2. max Both were 5.9%, with a total deviation of D. total All are 3.1%, all are less than 10%, which shows that they have high uniformity of air-side flow and strong stability, thus improving reliability.

[0085] Combined with appendix Figure 18 and 24 The figures show the gas-side pressure distribution diagrams for Analysis Example 1 and Analysis Example 2, respectively. The pressure distribution diagrams in the figures represent the gas-side pressure magnitude of the heat exchanger tube profile (unit: Pa). The gas-side flow resistance of Analysis Example 1 and Analysis Example 2 is 1.26 kPa, which is less than 1.9 kPa. They have the characteristic of low gas-side pressure loss, which can effectively improve the engine's EGR rate, thereby improving the engine's thermal efficiency, and at the same time reduce the risk of carbon buildup in the cooler to a certain extent.

[0086] Under a given inlet water pressure of 130 kPa, the pipe wall temperature needs to reach 186.8℃ for the internal coolant to boil. (This is in conjunction with the attached...) Figure 19 and 25 The figures show the heat exchanger tube temperature cloud maps for Analytical Example 1 and Analytical Example 2, respectively. The temperature distribution map in the figure represents the temperature of the heat exchanger tube wall (unit: °C). The highest tube wall temperatures in Analytical Example 1 and Analytical Example 2 are 162 °C and 146 °C, respectively, and the actual boiling region area and boiling ratio are both 0.

[0087] Example 2

[0088] Based on Example 1, this example discloses an EGR cooler that adopts the EGR cooler cooling structure layout design method described in Example 1.

[0089] This invention addresses the problems of high gas-side pressure loss, small liquid contact area, insufficient compactness, and poor reliability in existing finned EGR coolers. It adopts a square cross-section pipe design, which has a larger surface area than a circular pipe, thus improving heat exchange efficiency. Recesses are created on the inner wall of the pipe to increase fluid turbulence, break the fluid boundary layer, and enhance heat transfer, effectively increasing the engine's EGR rate and thus improving engine thermal efficiency. Compared to traditional finned coolers, it has lower gas-side pressure loss and reduces the risk of carbon buildup in the cooler. It also eliminates the need for frequent cleaning, effectively reducing maintenance costs and downtime, and ensuring continuous engine operation.

[0090] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any way. Any simple modifications, equivalent changes, or alterations made to the above embodiments based on the technical principles of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A method for designing the cooling structure layout of an EGR cooler, comprising the design of a matrix pipe layout structure and the design of a heat dissipation pattern, characterized in that: The design of a matrix-style piping layout includes the following steps: A1. Calculation of the overall heat transfer area based on the heat transfer rate equation. Calculate the required heat exchange area A, where Q is the heat transfer volume, K is the overall heat transfer coefficient, and ΔT is the total heat transfer area. lm The logarithmic mean temperature difference; A2. Calculate the required number of single tubes N. Where A0 is the heat exchange area of ​​a single tube; A3. Calculate the inner diameter D of the shell when using a single-pass tube. When using multi-pass, Where t is the tube center distance, n c The number of tubes crossing the centerline of the tube bundle, k is a coefficient, and d o Where η is the outer diameter of the tube and η is the tube sheet utilization rate. A4. Determine the pipe spacing; The design of the heat dissipation pattern includes the following steps: S1. Determine the pattern type, which can be any one of the following: pit array, wave pattern, or diamond pattern structure; S2. Determine the arrangement rules for the inner and outer surfaces; The design device for implementing the matrix-style pipeline layout structure design and heat dissipation pattern design includes: EGR cooler model drawing module: used to create the model of the EGR cooler and determine the layout range of the matrix piping based on the size of the EGR cooler; The parameter setting module for the EGR cooler is used to set the intake air temperature, intake air flow rate, intake air pressure, liquid inlet temperature, and liquid inlet flow rate. The parameter calculation module for the matrix piping is used to calculate various parameters of the matrix piping layout and heat dissipation pattern based on the parameters set in the parameter setting module of the EGR cooler mentioned above. The matrix piping synthesis module is used to synthesize the various parameters of the matrix piping obtained from the above matrix piping parameter calculation module with the EGR cooler model drawn in the EGR cooler model drawing module to obtain an EGR cooler containing matrix piping. The parameter testing module for EGR coolers is used to obtain various performance indicators of the EGR cooler based on the matrix piping synthesis module obtained above, through three-dimensional simulation or actual testing.

2. The EGR cooler cooling structure layout design method according to claim 1, characterized in that: In step A4, the pipe spacing is 1-2 mm.

3. The EGR cooler cooling structure layout design method according to claim 1, characterized in that: In step S1, the pit array has a depth of 0.1-0.3 mm and a diameter of 1-2 mm; the wave pattern has an amplitude of 0.15-0.25 mm and a wavelength of 3-5 mm; the diamond pattern has a height of 0.5-1 mm and a spacing of 2-3 mm.

4. The EGR cooler cooling structure layout design method according to claim 3, characterized in that: In step S2, the inner surface adopts a 35-55° oblique cross pattern, and the outer surface adopts a radial protrusion array.

5. The EGR cooler cooling structure layout design method according to claim 4, characterized in that: The bottom length of the matrix-type pipeline is L1, and the distance from the bottom of the matrix-type pipeline to the protrusion in the outer surface protrusion array is L2. .

6. The EGR cooler cooling structure layout design method according to claim 5, characterized in that: The porosity factor F of the matrix-type pipeline ranges from 0.6 to F < 0.9, where... Where A1 is the surface area of ​​the outer surface of all heat exchange tubes in the matrix pipeline, and A2 is the surface area of ​​the protrusions in the protrusion array of the outer surface of all heat exchange tubes in the matrix pipeline.

7. A cooling structure layout design method for an EGR cooler according to any one of claims 1 to 6, characterized in that: The matrix-type pipeline layout can adopt a regular or irregular structure. When a regular structure is adopted, it includes a first regular area with a rectangular cross-section, and several heat exchange tubes fill the first regular area.

8. The EGR cooler cooling structure layout design method according to claim 7, characterized in that: When the matrix pipeline layout adopts an irregular structure, it also includes an irregular region. The irregular region includes a second regular region and an irregular region. The cross-section of the second regular region is the rectangle with the largest area in the irregular region, and several heat exchange tubes fill the second regular region.

9. The EGR cooler cooling structure layout design method according to claim 8, characterized in that: The first and second rule areas adopt a matrix-style pipeline layout and a heat dissipation pattern design.

10. An EGR cooler, characterized in that: The EGR cooler cooling structure layout design method described in any one of claims 7 to 9 is adopted.

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