Method for regulating and controlling transverse difference of cold conduction performance of permafrost pipeline ventilation roadbed

Abstract

The invention relates to the technical field of heat transfer design in a ventilation roadbed, in particular to a method for regulating and controlling transverse difference of cold conduction performance of a permafrost pipeline ventilation roadbed. According to the method, the ventilation pipeline is segmented, and comprehensive heat exchange factors needed for achieving a homogenization index at different pipeline segment positions are calculated according to the current convective heat exchange coefficient distribution condition of the pipeline; and then, according to the relation between the comprehensive heat exchange factors and the structural parameters of the enhanced heat exchange winglets, the enhanced heat exchange winglets with specific structural parameters are reasonably selected to be arranged at the fixed-point positions, and the existing convective heat exchange coefficients are compensated at different pipe section positions. Therefore, the purposes of regulating and controlling the transverse difference of the cold conduction performance of the pipeline ventilation roadbed and improving the uniformity of the embankment environment temperature are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of heat transfer design in ventilation pipeline foundation pipes, and in particular to a method for regulating lateral differences in cooling performance of ventilation foundation pipes in permafrost soil. Background Art

[0002] The ventilation pipe roadbed has a significant cooling effect compared to the roadbed without ventilation pipes. The temperature influence range of the ventilation pipe can reach 1.0-1.5 meters. The structural form of the ventilation pipe roadbed can effectively provide cold energy for the embankment soil, playing an important role in protecting frozen soil and maintaining the stability of frozen soil embankments.

[0003] At present, one of the main problems of the existing ventilation pipe subgrade is that the convective heat transfer intensity in the pipe is different, and it shows a general decreasing pattern from the air inlet to the air outlet (such as Figure 1 ), causing significant differences in the cooling performance in the lateral direction, which is manifested as a large lateral temperature gradient difference in the frozen soil after the pipeline heat is conducted to the underlying foundation. The wide roadbed and the yin-yang slope effect will aggravate this phenomenon, resulting in asymmetric temperature fields between the ventilation pipe roadbed and the underlying foundation, and uneven thermal energy in space, which can easily cause roadbed tilt, slope landslides and other diseases, affecting the safety and healthy operation of the project.

[0004] Therefore, when designing and applying ventilation pipe roadbed, the non-uniformity of the embankment ambient temperature should be fully considered, and relevant measures should be taken to reduce its impact on the project. Summary of the invention

[0005] The purpose of the present invention is to provide a method for regulating the lateral difference in cooling performance of permafrost pipeline ventilation roadbed in view of the problem that there is a large lateral difference in cooling performance in ventilation pipes of the prior art ventilation roadbed.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is: A method for regulating the lateral difference in cooling performance of a permafrost pipeline ventilation roadbed comprises the following steps: S1: Get different positions along the length of the ventilation pipe x 1. x 2. x 3. ……x n Convective heat transfer coefficient on the tube wall surface h 1. h 2. h 3. ……h n (Subscript n is a positive integer, only to distinguish different positions); determine the uniformity target of the convective heat transfer coefficient as h surf ; S2: Determine the different locations of the ventilation pipes x 1. x 2. x 3. ……x n The tube wall surface should achieve the uniformity target of the convective heat transfer coefficient. h surf The required comprehensive heat transfer factors are PEC1, PEC2, PEC3, ...PEC n (PEC stands for performance evaluation criterion); S3: Determine the structural parameters of the enhanced heat exchange winglet according to the comprehensive heat exchange factor PEC required at different positions of the ventilation pipe; S4: In different locations x 1. x 2. x 3. ……x n Small heat exchange enhancement wings with corresponding structural parameters are installed on the pipe wall to compensate for the convective heat exchange intensity of the pipe wall sections at different positions of the ventilation pipe.

[0007] The present invention divides the ventilation duct into sections, calculates the comprehensive heat transfer factor required to achieve the uniformity index at different pipe section positions according to the current distribution of the convective heat transfer coefficient of the duct, and then reasonably selects the enhanced heat transfer winglet with specific structural parameters for arrangement at the fixed point position according to the relationship between the comprehensive heat transfer factor and the structural parameters of the enhanced heat transfer winglet, so as to compensate for the existing convective heat transfer coefficient at different pipe section positions, thereby achieving the purpose of regulating the lateral difference of the cooling performance of the ventilation roadbed of the duct and leveling the convective heat transfer intensity in the duct. Among them, the above-mentioned comprehensive energy conversion factor is used to characterize the comprehensive heat transfer performance of the duct.

[0008] It should be noted that increasing the heat exchange area by setting enhanced heat exchange wings in the ventilation heat exchange structure is a common heat transfer enhancement measure. The specific structure of the enhanced heat exchange winglets can have a variety of structural forms. It is an existing mature technology and its heat exchange principle will not be elaborated in this article.

[0009] As a preferred embodiment of the present invention, h surf Pick h 1. h 2. h 3. ……h n The maximum value in h surf The corresponding position is x i , i 1- n If any one of the following is true, then in step S4, when installing the enhanced heat exchange winglet,x 1. x 2. x 3. ……x n Medium x i Installation of enhanced heat exchange winglets is carried out in locations other than the above.

[0010] As another possible implementation, h surf The value can also be preset according to actual needs.

[0011] As a preferred solution of the present invention, in step S1, the step of obtaining the heat transfer coefficient of the tube wall surface at different positions includes: S11: Modeling of ventilation pipe roadbed according to the climatic conditions of the area where the roadbed is located in the permafrost region; S12: Derivation of the convection heat transfer coefficient of the tube wall surface h The relationship change diagram along the length of the ventilation pipe; S13: On the relationship change diagram, discard the points where the convective heat transfer coefficients on both sides of the air inlet and the air outlet of the ventilation pipe are negative, and perform interpolation fitting on the remaining points to obtain h = P(x) , record the maximum convective heat transfer coefficient on the tube wall near the air inlet h max and its corresponding position x 1; S14: x 1 as the reference, record the position of each point deep inside the pipe at a preset interval a. x 2. x 3. ……x n , and according to the fitting formula h = P(x) Calculate the surface convection heat transfer coefficient of each corresponding point h 2. h 3. ……h n ,in h max > h 2> h 3> h n ; Accordingly, in step S4, x 2. x 3. ……x n Heat exchange enhancement wings with corresponding structural parameters are respectively installed at the pipe walls to compensate for the convective heat exchange intensity, thereby achieving the effect of basically leveling the convective heat exchange intensity at different axial positions of the ventilation pipe.

[0012] As a preferred solution of the present invention, the preset spacing is a, and the value range of a is 0.5m≤a≤2m.

[0013] As a preferred embodiment of the present invention, in step S2, x n The comprehensive heat transfer factor PEC required at the position is obtained by the following expression: , n Is a positive integer.

[0014] As a preferred embodiment of the present invention, in step S3, the heat exchange enhancement winglet adopts a rectangular structure, and according to the comprehensive heat exchange factor of the heat exchange enhancement winglet PEC Determine the aspect ratio of the heat transfer enhancement winglet l / D and angle of attack β .

[0015] This scheme preferably adopts rectangular enhanced heat transfer winglets, which have a simple structure and convenient structural parameter design. When calculating, the comprehensive heat transfer factor PEC and structural parameter of the existing enhanced heat transfer winglet - aspect ratio can be used. l / D and angle of attack β The functional relationship between them determines the heat transfer enhancement winglets to be installed at each position to achieve h surf The corresponding structural parameters required by x 1. x 2. x 3. ……x n Installing enhanced heat transfer wings with corresponding aspect ratio and angle of attack on the pipe wall can compensate for the convective heat transfer intensity at different fixed points, so that each position x 1. x 2. x 3. ……x n After installing the enhanced heat transfer winglet, the convective heat transfer intensity can reach h surf , thereby achieving uniform convective heat transfer intensity in the tube.

[0016] As other possible implementation methods, the heat exchange enhancement winglet may also adopt other structural forms such as a wedge with a triangular cross-section. Accordingly, the corresponding relationship between the comprehensive heat exchange factor PEC and the structural parameters should also change accordingly.

[0017] As a preferred embodiment of the present invention, in step S3, when determining the structural parameters of the enhanced heat exchange winglet, the comprehensive heat transfer factor of the ventilation duct with the rectangular enhanced heat exchange winglet is first calculated according to the wind speed conditions, and the influence of the structural parameters of the enhanced heat exchange winglet on the overall heat transfer performance is given in the form of a contour diagram, and finally, the corresponding PEC contour design aspect ratio and angle of attack are selected according to the comprehensive heat exchange factor PEC that needs to be compensated.

[0018] As a preferred embodiment of the present invention, in step S3, the comprehensive heat transfer factor PEC, aspect ratio l / D and angle of attack β Calculated by the following expression: ; ; ; ; ; In the formula, V m is the average wind speed in the pipe, in m / s; Nu 0 and f 0 represents the Nusselt number and friction coefficient of the ventilation duct without enhanced heat transfer winglets, Nu 0 and f 0 is a dimensionless quantity; Nu and f They represent the Nusselt number and friction coefficient of the ventilation duct with enhanced heat transfer wings, Nu and f All are dimensionless quantities; Re is the Reynolds number, a dimensionless quantity; D is the inner diameter of the ventilation pipe, in m; L is the length of the ventilation pipe, in meters; Pr is the Prandtl number, a dimensionless quantity; l The length of the winglet to enhance heat transfer, in meters; β The angle of attack of the winglet to enhance heat transfer, in degrees; express PEC It is about the average wind speed V m , Enhanced heat transfer winglet aspect ratio l / D and angle of attack β The ternary function of .

[0019] As a preferred embodiment of the present invention, in step S4, 4 to 12 heat exchange enhancement winglets are pasted on the inner wall of the ventilation pipe at equal intervals.

[0020] As a preferred solution of the present invention, the enhanced heat exchange winglet is made of flexible material, and the height of the enhanced heat exchange winglet is set within 3 mm and the thickness is set within 1 mm, which is conducive to reducing pressure loss.

[0021] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: The present invention achieves the purpose of regulating the lateral difference of the cooling performance of the pipeline ventilation roadbed and improving the uniformity of the ambient temperature of the embankment by performing a uniform leveling design on the convective heat exchange intensity in the ventilation pipeline roadbed, thereby improving the safety of the project and playing an important role in protecting frozen soil and maintaining the stability of frozen soil embankments. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a graph showing the variation of the convection heat transfer coefficient along the inner wall of a common ventilation duct; Figure 2 It is a structural arrangement diagram of the rectangular enhanced heat exchange winglet on the cross section of the ventilation pipe; Figure 3 It is a structural arrangement diagram of the rectangular enhanced heat exchange winglet in the axial direction of the ventilation pipe; Figure 4 is a schematic structural diagram of a rectangular enhanced heat exchange winglet in Example 1; Figure 5 It is a schematic diagram of the structure of the ventilation duct foundation with enhanced heat exchange wings; Figure 6 It is the contour diagram of the parameter design method of aspect ratio and angle of attack under the target PEC; Figure 7 It is a technical roadmap of the design process in Example 1; Figure 8 It is a schematic diagram of the structure of another structural form of the enhanced heat exchange winglet; Fig. 9 It is a schematic diagram of the structure of another structural form of enhanced heat exchange winglets.

[0023] Icons: 1-ventilation duct; 2-enhanced heat exchange winglet. DETAILED DESCRIPTION

[0024] The present invention will be described in detail below in conjunction with the accompanying drawings.

[0025] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0026] Example A method for regulating the lateral differences in cooling performance of permafrost pipe ventilation embankment, such as Figure 1-Figure 7As shown, the following steps are included: Step 1: Monitor the climatic conditions of the area where the roadbed is located in the permafrost region, summarize the local wind speed, temperature, surface and roadbed temperature in a year, and fully consider the yin and yang slope effects on both sides of the roadbed to model and perform numerical calculations on the ventilation pipe roadbed. On this basis, derive the convection heat transfer coefficient of the pipe wall surface h ,like Figure 1 .

[0027] Step 2: discard the points with negative convective heat transfer coefficients on both sides of the air inlet and outlet of ventilation pipe 1, and interpolate and fit the remaining points to obtain h = P(x) , record the maximum convective heat transfer coefficient on the tube wall h max and its corresponding position x 1 (near the air inlet). The maximum convective heat transfer coefficient on the tube wall h max As the target of the uniformity of the convective heat transfer coefficient in this embodiment, h surf ( h surf is a positive number).

[0028] Step three, x 1 is used as the reference, and the position of each point is recorded deep inside the pipe at a preset interval, such as 2m. x 2. x 3. ……x n , and according to the fitting formula h = P(x) Calculate the surface convection heat transfer coefficient of each corresponding point h 2. h 3. …… h n ,in h max > h 2> h 3> h n , subscript n It only indicates the number of different positions and is a positive integer.

[0029] Step 4: x 2. x 3. ……x n The pipe wall is equipped with an enhanced heat transfer wing 2 to compensate for the convective heat transfer intensity. The convective heat transfer intensity after compensation reaches h 2* PEC2, h 3* PEC3,…… h n*PEC n , making them equal to h surf (Right now h max ),Right now , ,…… , where PEC refers to the comprehensive heat transfer factor of the enhanced heat transfer winglet 2, which is a dimensionless quantity, and its full name is performance evaluation criterion.

[0030] After the heat transfer enhancement winglet 2 is installed in the pipeline, when the fluid passes through its surface, it will flow around and generate rotating vortices along the mainstream direction. Such vortices have been proven by the prior art to effectively increase the velocity gradient near the wall surface, thereby enhancing convective heat transfer. The heat transfer enhancement winglet 2 in this embodiment adopts a rectangular structure, which is simple in structure and easy to design structural parameters. According to the PEC required for each wall section and the local average wind speed V m Design of the required aspect ratio for the heat transfer enhancement winglet 2 l / D and angle of attack ;like Figure 2-Figure 4 As shown, in this embodiment, the length direction of the enhanced heat exchange winglet 2 is set at a certain inclination angle along the axial direction of the ventilation pipe 1. When ventilation is carried out along the axial wind direction of the ventilation pipe 1, the airflow will blow to the enhanced heat exchange winglet 2 at different angles and flow around the surface of the enhanced heat exchange winglet 2 at a certain angle, thereby producing different convective heat exchange effects. In this embodiment, the angle between the length direction of the enhanced heat exchange winglet 2 and the axial direction of the ventilation pipe is the angle of attack. β ,like Figure 3 , Figure 4 Specifically, the calculation method of the comprehensive heat transfer factor PEC of the enhanced heat transfer winglet 2 can be expressed as: ; in, express PEC It is about the average wind speed V m , Enhanced heat transfer winglet 2 aspect ratio l / D and angle of attack β The average wind speed V m can be regarded as a constant, so PEC can be degenerated into a factor including the aspect ratio l / D and angle of attack β A binary function of .

[0031] PEC is calculated as follows: ; in Nu 0 and f0 represents the Nusselt number and friction coefficient of the ventilation duct without the enhanced heat transfer winglet 2, Nu 0 and f 0 is a dimensionless quantity; Nu and f They represent the Nusselt number and friction coefficient of the ventilation duct 1 with the enhanced heat transfer winglet 2, Nu and f All are dimensionless quantities;.

[0032] Ventilation pipe 1 without enhanced heat exchange winglet 2 Nu 0 can be estimated by the Gnielinski formula, expressed as: ; in, Re is the Reynolds number, a dimensionless quantity, , V m is the average wind speed in the pipe (in m / s), with an annual average of 3.0-6.0 m / s on the Qinghai-Tibet Plateau, which is higher in winter than in summer; D is the inner diameter of the ventilation pipe (in meters), take 40cm; v is the kinematic viscosity, about 2.7310-5m 2 / s. So 10 4 < Re <10 5 , for fully developed turbulence.

[0033] Friction coefficient f 0 can be expressed using the Blasius correlation: ; Prandtl number , Prandtl number Pr It is a dimensionless quantity. At an altitude of more than 4,500 meters on the Qinghai-Tibet Plateau, the specific heat of air at constant pressure is c p =1.004 kJ / kg, dynamic viscosity μ =1.75kg / ms, thermal conductivity =0.02W / m, we get Pr =0.84. Inner diameter of a single ventilation pipe D =40cm, tube length L =2m.

[0034] In the ventilation duct with rectangular enhanced heat exchange winglet 2 Nu and f It can be expressed by the following experimental correlation: ; ; In the formula, V m is the average wind speed in the pipe (in m / s), Re is the Reynolds number (dimensionless quantity), D is the inner diameter of the ventilation pipe 1 (in m), L is the length of ventilation pipe 1 (in m), Pr is the Prandtl number (dimensionless quantity), l The length of the heat transfer winglet 2 (unit: m) is β is the angle of attack of the heat exchange enhanced winglet 2 (in degrees).

[0035] When determining the structural parameters of the enhanced heat exchange winglet 2, based on the above calculation method, the above relationship is edited by the subroutine, and the comprehensive heat exchange factor of the ventilation duct 1 with the rectangular enhanced heat exchange winglet 2 under different wind speed conditions is calculated in the main program, and the following is used: Figure 6 The influence of the structural parameters of the heat exchange enhancement winglet 2 on the overall heat exchange performance is given in the form of contour diagrams shown. Finally, the corresponding PEC contour line is selected according to the comprehensive heat exchange factor PEC required to be leveled to determine the appropriate aspect ratio and angle of attack.

[0036] Furthermore, the empirical formula corresponding to any isovalue line can be obtained through curve fitting: When PEC=1.05, the aspect ratio l / D and angle of attack β The relationship is: ; When PEC=1.10, the aspect ratio l / D and angle of attack β The relationship is: .

[0037] Step 5: In different locations x 1. x 2. x 3. ……x n A heat exchange enhancement winglet 2 with corresponding structural parameters is installed on the tube wall to compensate for the convective heat exchange intensity of the tube wall sections at different positions.

[0038] Specifically, exemplarily, Figure 2 , Figure 5 As shown, during installation, 4-12 enhanced heat exchange wings 2 are pasted at equal intervals on the inner wall of the ventilation pipe 1. The enhanced heat exchange wings 2 are made by 3D printing, and the material is a flexible material such as nylon or resin. The height of the enhanced heat exchange wings 2 is set within 3mm and the thickness is set within 1mm to reduce pressure loss.

[0039] This embodiment divides the ventilation duct into sections, calculates the comprehensive heat transfer factor required to achieve the uniformity index at different pipe section positions according to the current distribution of the convective heat transfer coefficient of the duct, and then reasonably selects the enhanced heat transfer winglet 2 with specific structural parameters for arrangement at a fixed point position according to the relationship between the comprehensive heat transfer factor and the structural parameters of the enhanced heat transfer winglet 2, so as to compensate for the existing convective heat transfer coefficient at different pipe section positions, thereby achieving the purpose of regulating the lateral difference in the cooling performance of the ventilation roadbed of the duct and leveling the convective heat transfer intensity in the duct. The comprehensive heat transfer factor in this article is used to characterize the comprehensive heat transfer performance of the duct.

[0040] The method provided in this embodiment achieves the purpose of regulating the lateral difference of the cooling performance of the pipeline ventilation roadbed and improving the uniformity of the ambient temperature of the embankment by performing a uniform leveling design on the convective heat transfer intensity in the ventilation pipeline roadbed, which is beneficial to improving the safety of the project and plays an important role in protecting frozen soil and maintaining the stability of frozen soil embankments.

[0041] As other possible implementation methods, the heat transfer enhancement winglets for enhancing convective heat transfer may also adopt a triangular prism, a fan-shaped cross-section, and other structural forms, such as Figure 8 , Fig. 9 As shown, during installation, the height direction of the triangular prism is arranged along the axis direction of the ventilation pipe, and the chord length direction of the fan-shaped cross-section structure is arranged along the axis direction of the ventilation pipe, so as to connect with the pipe wall with a larger contact surface area, which is not limited to the above examples. Accordingly, the enhanced heat exchange winglets based on different structural forms have different compensation capabilities for the comprehensive heat exchange performance, and there are different correlations between their structural parameters and comprehensive heat exchange factors, but they can still be applied to the leveling design ideas provided in this embodiment.

[0042] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for regulating the lateral difference in cooling performance of permafrost pipeline ventilation roadbed, characterized in that: The following steps are involved: S1: Get different positions along the length of the ventilation pipe x 1. x 2. x 3. ……x n Convective heat transfer coefficient on the tube wall surface h 1. h 2. h 3. ……h n , n is a positive integer; the uniformization target of the convective heat transfer coefficient is determined as h surf ; S2: Determine the different locations of the ventilation pipes x 1. x 2. x 3. ……x n The tube wall surface should achieve the uniformity target of the convective heat transfer coefficient. h surf The required comprehensive heat transfer factors are PEC1, PEC2, PEC3, ...PEC n ; S3: Determine the structural parameters of the enhanced heat exchange winglet according to the comprehensive heat exchange factor PEC required at different positions of the ventilation pipe; S4: In different locations x 1. x 2. x 3. ……x n Small heat exchange enhancement wings with corresponding structural parameters are installed on the pipe wall to compensate for the convective heat exchange intensity of the pipe wall sections at different positions of the ventilation pipe.

2. The method for regulating the lateral difference of cooling performance of permafrost pipeline ventilation roadbed according to claim 1, characterized in that: h surf Pick h 1. h 2. h 3. ……h n The maximum value in h surf The corresponding position is x i , i 1- n If any one of the following is true, then in step S4, when installing the enhanced heat exchange winglet, x 1. x 2. x 3. ……x n Medium x i Installation of enhanced heat exchange winglets is carried out in locations other than the above.

3. The method for regulating the lateral difference of cooling performance of permafrost pipeline ventilation roadbed according to claim 2, characterized in that: In step S1, the step of obtaining the heat transfer coefficient of the tube wall surface at different positions includes: S11: Modeling of ventilation pipe roadbed according to the climatic conditions of the area where the roadbed is located in the permafrost region; S12: Derivation of the convection heat transfer coefficient of the tube wall surface h The relationship change diagram along the length of the ventilation pipe; S13: On the relationship change diagram, discard the points where the convective heat transfer coefficients on both sides of the air inlet and the air outlet of the ventilation pipe are negative, and perform interpolation fitting on the remaining points to obtain h = P ( x ), record the maximum convective heat transfer coefficient on the tube wall near the air inlet h max and its corresponding position x 1; S14: x 1 as the reference, record the position of each point deep inside the pipe at a preset interval a. x 2. x 3. ……x n , and according to the fitting formula h = P(x) Calculate the surface convection heat transfer coefficient of each corresponding point h 2. h 3. ……h n ,in h max > h 2> h 3> h n ; In step S4, x 2. x 3. ……x n Heat transfer enhancement wings with corresponding structural parameters are respectively installed at the tube walls to compensate for the convective heat transfer intensity.

4. The method for regulating the lateral difference of cooling performance of permafrost pipeline ventilation roadbed according to claim 3, characterized in that: The preset spacing is a, and the value range of a is 0.5m≤a≤2m.

5. The method for regulating the lateral difference of cooling performance of permafrost pipeline ventilation roadbed according to claim 1, characterized in that: In step S2, x n The comprehensive heat transfer factor PEC required at the position is obtained by the following expression: , n Is a positive integer.

6. The method for regulating the lateral difference of cooling performance of permafrost pipeline ventilation roadbed according to claim 1, characterized in that: In step S3, the enhanced heat exchange winglet adopts a rectangular structure, and the aspect ratio of the enhanced heat exchange winglet is determined according to the comprehensive heat exchange factor PEC of the enhanced heat exchange winglet. l / D and angle of attack β .

7. The method for regulating the lateral difference of cooling performance of permafrost pipeline ventilation roadbed according to claim 6, characterized in that: In step S3, when determining the structural parameters of the enhanced heat exchange winglet, the comprehensive heat transfer factor of the ventilation duct with the rectangular enhanced heat exchange winglet is first calculated according to the wind speed conditions, and the influence of the structural parameters of the enhanced heat exchange winglet on the overall heat transfer performance is given in the form of a contour diagram. Finally, the corresponding PEC contour design aspect ratio and angle of attack are selected according to the comprehensive heat exchange factor PEC that needs to be compensated.

8. The method for regulating the lateral difference of cooling performance of permafrost pipeline ventilation roadbed according to claim 7, characterized in that: In step S3, the comprehensive heat transfer factor PEC and aspect ratio of the heat transfer winglet are enhanced. l / D and angle of attack β Calculated by the following expression: ； ； ； ； ； In the formula, V m is the average wind speed in the pipe, in m / s; Nu 0 and f 0 represents the Nusselt number and friction coefficient of the ventilation duct without enhanced heat transfer winglets, Nu 0 and f 0 is a dimensionless quantity; Nu and f They represent the Nusselt number and friction coefficient of the ventilation duct with enhanced heat transfer wings, Nu and f All are dimensionless quantities; Re is the Reynolds number, a dimensionless quantity; D is the inner diameter of the ventilation pipe, in m; L is the length of the ventilation pipe, in meters; Pr is the Prandtl number, a dimensionless quantity; l The length of the small wing to enhance heat transfer, in meters; β The angle of attack of the winglet to enhance heat transfer, in degrees; express PEC It is about the average wind speed V m , Enhanced heat transfer winglet aspect ratio l / D and angle of attack β The ternary function of .

9. The method for regulating the lateral difference of cooling performance of permafrost pipeline ventilation roadbed according to any one of claims 1 to 8, characterized in that: In step S4, 4 to 12 heat exchange enhancement winglets are pasted on the inner wall of the ventilation pipe at equal intervals.

10. The method for regulating the lateral difference of cooling performance of permafrost pipeline ventilation roadbed according to claim 9, characterized in that: The enhanced heat exchange winglet is made of flexible material, and the height of the enhanced heat exchange winglet is set within 3 mm, and the thickness is set within 1 mm.

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