Leeward end special-shaped combined arrangement louver fin and heat exchanger

Abstract

The application discloses a kind of leeward terminal special-shaped combination arrangement louver fin and heat exchanger, louver fin includes outer frame main body and multiple louver blades, and the leeward terminal of louver blade is provided with special-shaped terminal structure, and special-shaped terminal structure at least includes two different forms, and combination arrangement is carried out according to preset arrangement relationship.The application introduces multiple types of special-shaped structure in the leeward terminal of louver blade and combination arrangement locally, actively breaks the tail edge phase-locked effect of traditional full same straight terminal and the main peak concentration tendency, effectively weakens the tendency of wind side high frequency whistle or discrete pure tone formation under the premise of not changing main platform parameters, simultaneously enhances local disturbance and boundary layer renewal, makes that heat transfer-flow resistance comprehensive performance evaluation index PEC is greater than 1 under all working conditions, realizes the collaborative promotion of noise reduction and heat transfer enhancement, and is easy to mass production by progressive die stamping.

Description

Technical Field

[0001] This invention relates to the field of heat exchanger fin technology, and more particularly to a leeward end irregularly arranged louvered fin and heat exchanger. Background Technology

[0002] Louvered fins are widely used on the air side of heat exchangers. Their main functions are to guide airflow, disrupt the thermal boundary layer, promote near-wall fluid mixing, and improve heat transfer capacity. Existing louvered fin designs typically focus on optimizing louver angles, fin spacing, louver thickness, and overall opening ratio to improve heat transfer performance or enhance overall performance.

[0003] However, existing louver fins still have significant shortcomings in acoustic optimization. Traditional louver fins mostly employ identical, straight, and uniform leeward end structures. When air flows through the trailing edge or leeward free end of the louver fin, unsteady pressure pulsations with a certain degree of coherence and trailing edge vortex shedding are easily formed. When the trailing edge geometry of multiple blades is highly consistent, the unsteady responses generated by different blades are prone to superimpose within a specific frequency range, resulting in high-frequency whistling, sharp pure tones, or discrete pure-tone noise that is subjectively perceived by the user.

[0004] Existing solutions that improve noise by significantly altering the main flow channel parameters or adding silencing structures typically lead to problems such as increased pressure drop, decreased heat transfer performance, increased manufacturing costs, or difficulties in mass production adaptation. Therefore, there is an urgent need for a louver fin structure that modifies only a localized area at the leeward end while simultaneously achieving noise reduction and optimized thermal performance. Summary of the Invention

[0005] The purpose of this invention is to address the aforementioned problems by providing a leeward-end irregularly shaped louvered fin and heat exchanger. By setting at least two different types of irregularly shaped end structures at the leeward end of the louvers and adopting orderly, non-periodic, quasi-random, or mixed arrangement methods, this invention reduces the tendency of high-frequency whistling or discrete pure tone formation on the wind side and optimizes the overall heat transfer-flow resistance performance without changing the platform parameters of the fin body as much as possible.

[0006] To achieve the above-mentioned objectives, the technical solution adopted by this invention is as follows: According to one aspect of the present invention, a leeward-end irregularly shaped louvered fins and a heat exchanger are provided, comprising an outer frame body and a plurality of louvered fins disposed within the outer frame body. The plurality of louvered fins are arranged sequentially along the airflow direction. The leeward-end of each louvered fin is provided with an irregularly shaped end structure. The irregularly shaped end structure includes at least two different shaped ends, and the different shaped ends are combined and arranged according to a preset arrangement relationship. The irregularly shaped ends are fixedly disposed in a local area of ​​the leeward-end of the louvered fins.

[0007] Preferably, the spacing between the louver fins is 1~1.8mm, the thickness is 0.08~0.2mm, and the angle between the louver fins and the outer frame body is 20~35°.

[0008] Preferably, the spacing between the louver fins is 1.1~1.5mm, the thickness is 0.1~0.18mm, and the angle between the louver fins and the outer frame body is 24~32°.

[0009] Preferably, the irregular end structure includes two or three of the following: type A irregular end, type B irregular end, and type C irregular end.

[0010] Preferably, the A-shaped irregular end includes serrated protrusions, which are arranged along the edge of the A-shaped irregular end to form a serrated end edge; The angle of deviation of the A-shaped end relative to the louver fin is -8°, the horizontal projection length of the A-shaped end is 0.36mm, the cutting depth of the serrated protrusion of the A-shaped end is 0.09mm, and the tooth height is 0.18mm.

[0011] Preferably, the B-shaped end includes wavy protrusions, which are arranged along the edge of the B-shaped end to form a smooth wavy end edge; The B-shaped end has a deflection angle of 0° relative to the louver fin, the horizontal projection length of the B-shaped end is 0.46 mm, the cutting depth of the wavy protrusion of the B-shaped end is 0.12 mm, and the tooth height is 0.13 mm.

[0012] Preferably, the C-shaped end includes serrated and wavy protrusions, which are arranged repeatedly along the edge of the C-shaped end to form a mixed wavy and serrated end edge. The C-shaped end is offset at an angle of 8° relative to the louver fin, the horizontal projection length of the C-shaped end is 0.56 mm, the cutting depth of the serrated or wavy protrusion of the C-shaped end is 0.14 mm, and the tooth height is 0.27 mm.

[0013] Preferably, the preset arrangement relationship includes one or more of the following: periodic ordered arrangement, mirror symmetric arrangement, grouped arrangement, gradient arrangement, alternating arrangement, non-periodic arrangement, quasi-random arrangement, and local clustered arrangement.

[0014] Preferably, a heat exchanger includes an inlet water collection chamber, an outlet water collection chamber, and heat dissipation pipes. A plurality of heat dissipation pipes are arranged at intervals between the inlet water collection chamber and the outlet water collection chamber. One end of each heat dissipation pipe is connected to the inlet water collection chamber, and the other end is connected to the outlet water collection chamber. The heat exchanger also includes irregularly shaped louvered fins arranged at the leeward end, and the louvered fins are fixedly arranged between two adjacent heat dissipation pipes.

[0015] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. This invention actively breaks the geometric consistency of the trailing edge and the consistency of the local flow phase by introducing and arranging various irregular structures at the leeward end, weakening the traditional trailing edge phase-locking effect and the main peak concentration trend, and dispersing and weakening the originally concentrated single pure tone peak, fundamentally reducing the conditions for the formation of high-frequency whistles.

[0016] 2. The irregularly shaped end of this invention alters the flow separation, reattachment, and boundary layer renewal processes near the trailing edge, enhancing local mixing. This significantly improves the heat transfer factor, ensuring that the comprehensive performance evaluation index PEC remains greater than 1 under all test conditions, achieving comprehensive performance optimization where the heat transfer gain outweighs the resistance cost.

[0017] 3. The structural modifications of this invention are limited to the local area at the leeward end, while the parameters of the main platform remain unchanged. Mass production can be achieved by adding a non-standard shaping station after the window opening and flipping station through a progressive die continuous stamping process, resulting in low modification costs. Attached Figure Description

[0018] Figure 1 This is a three-dimensional structural schematic diagram of the present invention; Figure 2 This is a schematic diagram of a partial structure of the A-type irregular end of the present invention; Figure 3 This is a schematic diagram of a partial structure of the B-type irregular end of the present invention; Figure 4 This is a schematic diagram of a partial structure of the C-shaped irregular end of the present invention; Figure 5 This is a schematic diagram of the combined arrangement of the 14 louver fins of the present invention; Figure 6 This is a schematic diagram of the standard straight-end louver fin unit structure; Figure 7 This is a schematic diagram illustrating the mesh independence of the present invention; Figure 8 This is a diagram of CW correlation verification; Figure 9 This is a comparison diagram of j and f between the baseline group and the irregular group of this invention; Figure 10 This is a comparison diagram of the PEC of the baseline group and the irregular group of the present invention; Figure 11 This is the velocity cloud map of the present invention; Figure 12 This is the temperature cloud map of the present invention; Figure 13 This is a trace diagram of the present invention; Figure 14 This is a schematic diagram of the heat exchanger structure of the present invention.

[0019] In the attached diagram: 1. Outer frame; 2. Louver fins; 3. Type A irregular end; 4. Type B irregular end; 5. Type C irregular end; 6. Inlet water collection chamber; 7. Outlet water collection chamber; 8. Heat dissipation pipe; 9. Louver fins. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and preferred embodiments. However, it should be noted that many details listed in the specification are merely to provide the reader with a thorough understanding of one or more aspects of the invention, and these aspects of the invention can be achieved even without these specific details.

[0021] Please see Figures 1 to 14 This invention provides a leeward end irregularly shaped combination of louvered fins and a heat exchanger, the technical solution of which is as follows: like Figure 1-5 As shown, a leeward-end irregularly shaped arrangement of louver fins includes an outer frame body 1 and a louver fin assembly disposed within the outer frame body. The louver fin assembly includes multiple louver fins 2 arranged sequentially along the airflow direction. In this embodiment, 14 louver fins 2 are used as an arrangement unit, the fin spacing of the louver fins 2 is 1.8 mm, the louver spacing is 1.318 mm, the fin thickness is 0.16 mm, and the louver angle is 28°, wherein the leeward end of the louver fins 2 is fixedly provided with an irregularly shaped end structure.

[0022] The irregular end structure includes type A irregular end 3, type B irregular end 4, and type C irregular end 5. In this embodiment, the louver fin is used as a reference, and the angle between it and the outer frame body is set to 28°.

[0023] Among them, the A-type irregular end 3 is a backward-converging type. The A-type irregular end 3 has an angle increment of -8° relative to the louver fin 2, i.e., relative to the reference angle, and its final absolute angle is 20°. The A-type irregular end 3 includes serrated protrusions, which are repeatedly arranged along the edge length direction of the A-type irregular end 3 to form a serrated end edge. The microscopic morphology of the end edge is micro-serrated. Its end bending horizontal projection length is 0.36mm, the serration depth is 0.09mm, the transverse pitch is 0.18mm, and the tooth height is 0.18mm.

[0024] The B-type irregular end 4 maintains the baseline type. The angle increment of the B-type irregular end 4 relative to the louver fin 2 (i.e., relative to the baseline) is 0°, and its final absolute angle is 28°. The B-type irregular end 4 includes wavy protrusions, which are repeatedly arranged along the edge length direction of the B-type irregular end 4, forming a smooth wavy end edge. The microscopic morphology of the end edge is a smooth wave shape. Its end bend horizontal projection length is 0.46 mm, wave depth is 0.12 mm, transverse pitch is 0.23 mm, and wave height is 0.13 mm.

[0025] The C-shaped end 5 is a forward-opening type. The C-shaped end 5 has an 8° relative angle increment to the louver fin 2 (i.e., relative to the reference angle), and its final absolute angle is 38°. The C-shaped end 5 includes serrated and wavy protrusions, which are arranged repeatedly along the edge of the C-shaped end 5, forming a mixed wavy and serrated end edge. The microscopic morphology of the end edge is a mixture of wavy and serrated. Its horizontal projection length of the end bend is 0.56 mm, the cutting depth is 0.14 mm, the transverse pitch is 0.27 mm, and the tooth / wave height is 0.27 mm.

[0026] Type A irregular end 3, Type B irregular end 4, and Type C irregular end 5 can be distinguished by the horizontal projection length of the end bend, the final absolute included angle of the end, the relative reference angle increment, the micro-morphology of the end edge, the sawtooth / wave cutting depth, the lateral pitch, and the tooth / wave height. The parameters for each type are shown in Table 1 below. Table 1 Comparison of A / B / C Type Irregular End Parameters In this embodiment, the reference louver angle is 28°. Therefore, the A-type irregular end 3 is a backward convergence type relative to the reference angle, the B-type irregular end 4 is a reference retention type, and the C-type irregular end 5 is a forward opening type relative to the reference angle.

[0027] Different shaped ends are combined and arranged according to a preset arrangement. At least two different types of shaped ends are combined among multiple louver slats to form a combined arrangement structure for the leeward ends. The combined arrangement structure can form an arrangement relationship within the same arrangement unit. Arrangement relationships include, but are not limited to, one or more of the following: periodic ordered arrangement, mirror symmetry arrangement, grouped arrangement, gradient arrangement, alternating arrangement, non-single periodic arrangement, preset quasi-random arrangement, and local clustered arrangement. In this embodiment, the arrangement relationship of the 14 louver slats is AABCCBA│AABCCBA. This non-periodic arrangement with mirror symmetry effectively breaks the trailing edge phase-locked effect.

[0028] like Figure 14As shown, this invention also discloses a heat exchanger, including an inlet water collection chamber 6, an outlet water collection chamber 7, and heat dissipation pipes 8. Multiple heat dissipation pipes 8 are spaced apart between the inlet water collection chamber 6 and the outlet water collection chamber 7. One end of each heat dissipation pipe 8 is connected to the inlet water collection chamber 6, and the other end is connected to the outlet water collection chamber 7. It also includes irregularly shaped louvered fins 9 arranged at the leeward end, which are fixedly disposed between two adjacent heat dissipation pipes 8. The heat exchanger can be used as an intercooler, condenser, evaporator, radiator, air conditioning heat exchanger, heat pump heat exchanger, heat pump dryer heat exchanger, and other heat exchange equipment that uses louvers as an air-side heat exchange enhancement structure.

[0029] like Figure 7-13 As shown, to verify the effectiveness of the present invention, numerical simulation and comparative analysis were performed. The baseline model of the comparison group is as follows. Figure 6 As shown, its end has no irregular structure. A detailed analysis follows: Mesh independence verification: To ensure the reliability of the numerical simulation results, the mesh independence of the benchmark model was verified under the same boundary conditions. Pressure drop was selected. Heat transfer coefficient and by Calculated Using factors as monitoring parameters, a comparative analysis was conducted on five grid groups with approximately 900,000, 1.5 million, 2.5 million, 3.5 million, and 4.7 million data points. The results are shown in Table 2 below: Table 2. Mesh independence verification results As shown in Table 2, the pressure drop and heat transfer coefficient change significantly as the number of grid cells increases from 900,000 to 2.5 million. When the number of grid cells continues to increase from 2.5 million to 4.7 million, the relative changes in pressure drop and heat transfer coefficient become smaller, indicating that the calculation results are no longer sensitive to further grid refinement. Considering both computational accuracy and cost, approximately 2.5 million grid cells are preferred for subsequent numerical simulations.

[0030] CW correlation verification: To further verify the reliability of the numerical method, the CFD results of the baseline group of louver fins were compared with the results calculated using the CW empirical correlation. The comparison range was... .

[0031] The results show that CFD obtained The correlation between the factors and the CW results shows a consistent trend, with a relative deviation of approximately 0.89%–6.09% and an average deviation of approximately 3.06%; CFD results The results of the factor correlation also show a consistent trend, with a relative deviation of approximately 0.73% to 10.24% and an average deviation of approximately 5.32%. These deviations are within the acceptable range for engineering calculations, indicating that the numerical model used in this invention can predict the air-side heat transfer and resistance characteristics of louver fins well and has good reliability.

[0032] Heat transfer and flow resistance performance analysis: To evaluate the air-side thermal performance of irregularly shaped end-combination structures, this invention employs the heat transfer factor. To evaluate the air-side heat transfer capacity, the friction factor is used. The airflow resistance was evaluated, and the comprehensive performance evaluation index PEC was used to comprehensively weigh the improvement in heat transfer against the increase in resistance. The larger the factor, the stronger the heat transfer capacity on the air side; The larger the factor, the greater the air-side pressure drop loss. The comprehensive performance evaluation index PEC is calculated using the following formula: In the formula, and These are the working conditions corresponding to the benchmark group. Factors and Factor. When PEC>1, it indicates that the irregular structure is superior to the reference structure in terms of overall heat transfer and flow resistance performance.

[0033] Based on current thermal results, Under operating conditions, the reference group and the irregular group , The PEC data is summarized in Table 3 below: Table 3 Comparison of Thermal Performance of Baseline Group and Irregular Air Side Table 3 shows that the irregular-shaped assembly under all working conditions The factors were all higher than the baseline group, with increases ranging from approximately 4.46% to 5.79%, and an average increase of approximately 5.14%; meanwhile, The factors also increased, with an increase of approximately 4.66% to 6.13%, and an average increase of approximately 5.18%. The comprehensive performance evaluation index PEC was greater than 1 under all operating conditions, with a value range of 1.02880 to 1.03837 and an average value of approximately 1.03384.

[0034] In terms of heat transfer performance, the irregularly shaped assembly exhibits stable performance under all operating conditions. The increase in the factor indicates that the irregular combination arrangement at the leeward end has a continuous promoting effect on air-side heat transfer. Although the increase is not large, it has good operating stability, indicating that the irregular structure is not only effective at a single operating point, but can bring positive heat transfer benefits within the studied Reynolds number range.

[0035] From the perspective of drag resistance, the irregularly shaped group The factor increased synchronously compared to the baseline group, indicating that after the irregular end altered the flow structure near the trailing edge, while enhancing local mixing and fluid exchange, it also brought about certain additional friction and local losses. Therefore, this invention does not enhance heat transfer without cost, but rather achieves better overall performance by moderately increasing resistance.

[0036] From an overall performance perspective, although The factor increased, but PEC remained greater than 1 under all operating conditions, indicating that the heat transfer benefits obtained by the irregular structure group were higher than its flow resistance cost. In other words, the irregular structure was consistently superior to the benchmark structure in terms of comprehensive evaluation.

[0037] Traditional coherent straight-end structures tend to form relatively stable coherent wake structures behind the trailing edge due to their strong geometric consistency. On the one hand, this type of coherent structure limits the efficiency of local mixing and boundary layer renewal, and on the other hand, it tends to form relatively concentrated unsteady pressure pulsations, thereby inducing a tendency to form high-frequency whistles or discrete pure tones.

[0038] This invention breaks the state of completely uniform trailing edge geometry by introducing A-type, B-type, and C-type irregular ends at the leeward end of louver slats and forming a combined arrangement structure through the combination of multiple louvers. On the one hand, this measure discretizes the local shear layer, separation point, and reattachment position near the trailing edge, promoting local penetration flow and thermal boundary layer renewal, manifested as... The factor is steadily improved; on the other hand, this measure weakens the phase consistency and wake coherence of the trailing edge perturbation, thus providing a fluid basis for reducing the tendency of high-frequency whistles or discrete pure tones to form.

[0039] The irregularly shaped end combination arrangement structure has been achieved under all working conditions. The positive increase in the factor, although The factor increases synchronously, but PEC is always greater than 1, indicating that its comprehensive heat transfer-flow resistance performance is consistently better than the benchmark group, achieving comprehensive thermal optimization compatible with the noise reduction target.

[0040] Velocity field, temperature field, and trajectory analysis: Velocity field analysis As shown in the figure, the velocity contour plot reveals that the overall mainstream channel morphology of the irregular group is consistent with that of the baseline group. However, the irregular group exhibits more pronounced local acceleration at the trailing edge of the louvers and in areas of local channel contraction, with enhanced flow penetration in some channels. Simultaneously, several low-velocity stagnation zones behind the trailing edge are weakened, indicating that the irregular tip has a certain moderating effect on the flow organization in the wake region.

[0041] Temperature field analysis As seen in the temperature contour plot, the near-wall temperature gradient of the irregular-shaped group is slightly enhanced in the inlet to middle section region, and the thermal boundary layer near some louver surfaces is renewed more thoroughly, indicating improved heat exchange between the fluid and the wall. This phenomenon suggests that the irregular-shaped end, by adjusting the local flow structure at the trailing edge, enhances the refreshing effect of the mainstream on the heat exchange surface, thus leading to a stable increase in the j-factor. Simultaneously, the temperature field distribution of the irregular-shaped group is more uniform than that of the baseline group, indicating improved transition between local high-temperature and low-temperature regions, which is beneficial for the effective utilization of the heat exchange surface.

[0042] Trajectory Analysis The flow trajectory distribution shows that the trajectory deflection is more pronounced behind the trailing edge of the irregularly shaped group, with a slight enhancement in local reattachment and mixing. The originally relatively regular trailing structure has become somewhat dispersed. This indicates that the arrangement of irregularly shaped ends weakens the coherent structure of the trailing edge, causing the fluid organization downstream of the louvers to shift from relatively uniform to more discrete. This change is beneficial for boundary layer renewal and enhanced local heat transfer, and it is also consistent with the noise reduction mechanism of weakened trailing edge coherence. Therefore, flow analysis, thermal analysis, and acoustic analysis have a good mutual support relationship.

[0043] Based on the combined velocity field, temperature field, and trace results, it can be seen that the main mechanism of the irregular structure in this invention is not to improve performance by drastically changing the overall flow path, but rather to adjust the micro-flow organization through localized irregularization of the trailing edge, thereby moderately enhancing localized throughflow, shear mixing, and boundary layer renewal. As a result, the irregular group achieves a stable, slight improvement in heat transfer capacity, while maintaining consistently superior overall performance compared to the benchmark group.

[0044] Based on the local characteristic scale and local characteristic velocity of the trailing edge, the acoustic effect of the irregular end combination arrangement structure of the present invention is analyzed by estimating the characteristic frequency, which is used to explain its influence mechanism on the formation tendency of high-frequency whistles or discrete pure tones. It should be noted that this embodiment is not based on direct acoustic simulation or noise experiment results, but on estimation based on local structural scale and local velocity, which is used to illustrate the acoustic effect trend of the present invention, rather than to quantitatively limit the absolute noise value.

[0045] Traditional straight-end louvers have relatively consistent trailing edge geometry height and direction. When air flows through the trailing edge region, it is easy to form unsteady pressure pulsations with strong coherence and trail shedding, which in turn produces concentrated enhancement in a specific frequency band, manifesting as a tendency to form high-frequency whistles or discrete pure tones.

[0046] This invention introduces A-type, B-type, and C-type irregular structures at the leeward end of louver slats, and forms a combined arrangement structure by combining multiple louvers. This disrupts the uniformity of local geometry at the trailing edge, thereby weakening the phase consistency and phase-locking tendency of the trailing edge disturbance. Its effect is not simply to generate new frequencies, but to disperse or shift the originally concentrated trailing edge characteristic response by altering the coupling relationship between the trailing edge scale and local velocity.

[0047] Under the representative operating condition ReLp = 200: Inlet velocity U in = 2.14675 m / s, local characteristic velocity U at the leeward end loc = 2.356189 m / s. For the 14 complete irregular end arrangement model AABCCBA│AABCCBA, after statistical weighting according to the number of A / B / C types, the representative parameter is: representative tooth height or wave height of the irregular end h = 0.1914×10 -3 m, the representative transverse pitch λ of the irregular end is 0.3429×10 -3 m. For the reference straight-end structure, the representative characteristic length is taken as: representative characteristic length of the reference straight end l0 = 0.5429 × 10 -3 m.

[0048] Based on this calculation, we can obtain: in, The characteristic frequency is represented by the straight trailing edge of the reference point; The starting modulation frequency for the irregular structure; It is the main geometric modulation frequency for irregular structures.

[0049] The results above show that the characteristic frequency of the trailing edge of the reference straight end is approximately 4340 Hz. After introducing the irregularly shaped end combination arrangement, the trailing edge locally forms an initial modulation frequency of approximately 6154 Hz and a main geometric modulation frequency of approximately 6872 Hz. Compared with the reference structure, the main operating frequencies corresponding to the irregular structure are increased by approximately 1814 Hz and 2532 Hz, respectively.

[0050] This demonstrates that the irregular end combination arrangement structure of the present invention can introduce a new modulation scale outside the reference characteristic frequency, causing the trailing edge acoustic response to shift from the original relatively concentrated to dispersed, thereby helping to weaken the formation conditions of high-frequency whistles or discrete pure tones.

[0051] Based on the above estimation results, the differences between the baseline structure and the irregular structure under representative operating conditions are mainly concentrated in the frequency band of approximately 4.3 kHz to 6.9 kHz, of which the main modulation range of the irregular structure is approximately 6.15 kHz to 6.87 kHz.

[0052] Therefore, by setting different types of irregular ends and arranging them in combination, this invention breaks the geometric consistency and local perturbation consistency of the tail edge of traditional straight ends, so that the tail edge characteristic response changes from concentrated enhancement to dispersed modulation, which helps to reduce the tendency of high-frequency whistles or discrete pure tones to form.

[0053] The irregular end combination arrangement structure of the present invention can introduce frequency modulation effects of different characteristic scales by changing the local geometric continuity and perturbation organization of the trailing edge, thereby weakening the concentrated enhancement trend of the trailing edge acoustic response.

[0054] Based on comprehensive numerical reliability verification, thermal results, flow field analysis, and acoustic mechanism analysis, it can be concluded that the leeward end irregularly shaped louver fin arrangement proposed in this invention achieves excellent thermal performance under all research conditions. The positive increase in the factor, although While the factor increased, PEC remained consistently greater than 1, indicating that the irregular structure consistently outperformed the benchmark group in overall heat transfer and flow resistance performance. At the flow mechanism level, the combination and arrangement of irregular ends altered the local separation, reattachment, and shear layer organization near the trailing edge, enhancing local fluid exchange and thermal boundary layer renewal, and shifting the wake structure from relatively regular to moderately dispersed. At the acoustic mechanism level, the combination and arrangement of multiple types of irregular ends broke the geometric consistency and local perturbation consistency of the traditional perfectly straight trailing edge. Combined with the characteristic scale estimation results, it can be seen that this structure helps to weaken the formation conditions of high-frequency whistles or discrete pure tones, reducing the tendency for concentrated enhancement of the acoustic response at the trailing edge. This invention does not achieve a single performance improvement by drastically changing the parameters of the main platform, but rather achieves a comprehensive balance and optimization between air-side heat transfer, flow resistance, and acoustic performance based on the local irregularization and combination arrangement of the leeward ends of the louvers.

[0055] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A type of irregularly shaped louvered fin arrangement at the leeward end, comprising an outer frame body and a plurality of louvered fins disposed within the outer frame body, wherein the plurality of louvered fins are arranged sequentially along the airflow direction, characterized in that: The leeward end of the louver fin is provided with an irregular end structure, which includes at least two different types of irregular ends. The different types of irregular ends are combined and arranged according to a preset arrangement relationship. The irregular ends are fixedly set in a local area of ​​the leeward end of the louver fin.

2. The leeward-end irregularly shaped combined louver fins according to claim 1, characterized in that: The louver fins have a spacing of 1~1.8mm and a thickness of 0.08~0.2mm, and the angle between the louver fins and the outer frame body is 20~35°.

3. The leeward-end irregularly shaped combined louver fins according to claim 1, characterized in that: The louver fins have a spacing of 1.1~1.5mm and a thickness of 0.1~0.18mm, and the angle between the louver fins and the outer frame body is 24~32°.

4. The leeward-end irregularly shaped combined louver fins according to claim 1, characterized in that: The irregular end structure includes two or three of the following: type A irregular end, type B irregular end, and type C irregular end.

5. The leeward-end irregularly shaped combined arrangement of louver fins according to claim 4, characterized in that: The A-shaped irregular end includes serrated protrusions, which are arranged along the edge of the A-shaped irregular end to form a serrated end edge; The angle of deviation of the A-shaped end relative to the louver fin is -8°, the horizontal projection length of the A-shaped end is 0.36mm, the cutting depth of the serrated protrusion of the A-shaped end is 0.09mm, and the tooth height is 0.18mm.

6. The leeward-end irregularly shaped combined arrangement of louver fins according to claim 4, characterized in that: The B-shaped end includes wavy protrusions, which are arranged along the edge of the B-shaped end to form a smooth wavy end edge; The B-shaped end has a deflection angle of 0° relative to the louver fin, the horizontal projection length of the B-shaped end is 0.46 mm, the cutting depth of the wavy protrusion of the B-shaped end is 0.12 mm, and the tooth height is 0.13 mm.

7. The leeward-end irregularly shaped combined louver fins according to claim 4, characterized in that: The C-shaped irregular end includes serrated and wavy protrusions, which are arranged repeatedly along the edge of the C-shaped irregular end to form a mixed wavy and serrated end edge. The C-shaped end is offset at an angle of 8° relative to the louver fin, the horizontal projection length of the C-shaped end is 0.56 mm, the cutting depth of the serrated or wavy protrusion of the C-shaped end is 0.14 mm, and the tooth height is 0.27 mm.

8. The leeward-end irregularly shaped combined louver fins according to claim 1, characterized in that: The preset arrangement relationship includes one or more of the following: periodic ordered arrangement, mirror symmetric arrangement, grouped arrangement, gradient arrangement, alternating arrangement, non-periodic arrangement, quasi-random arrangement, and local clustered arrangement.

9. A heat exchanger, comprising an inlet water collection chamber, an outlet water collection chamber, and heat dissipation pipes, wherein a plurality of heat dissipation pipes are disposed at intervals between the inlet water collection chamber and the outlet water collection chamber, one end of each heat dissipation pipe being connected to the inlet water collection chamber and the other end being connected to the outlet water collection chamber, characterized in that: It also includes a leeward end irregularly shaped combination of louver fins as described in any one of claims 1 to 8, wherein the louver fins are fixedly disposed between two adjacent heat dissipation pipes.

Images