Large fan blade type louver capable of eliminating transverse vortex at end part of flow channel for ventilation regulation and control

Abstract

A large fan blade type louver capable of eliminating transverse vortex at the end of a flow channel for ventilation regulation and control comprises a louver frame and a large fan blade set, and the louver frame is of a rectangular frame or a truss structure and used for installing and supporting the large fan blade set; the large fan blade group comprises 1-12 large fan blades which are vertically arranged and can eliminate transverse vortexes at the end part of the air inlet flow channel; the large fan blade comprises an end vortex eliminating sealing device, a fan blade body and a fan blade rotating shaft. The end vortex eliminating sealing device is installed at the end of the air inlet side of the fan blade and can also be installed at the end of the air outlet side of the fan blade. When the large fan blade set is fully opened, the end vortex eliminating sealing device can reduce transverse vortexes at the end of an air inlet flow channel between the end vortex eliminating sealing device and the adjacent large fan blade by optimizing the flow field at the end of the air inlet side of the fan blade, so that the additional air inlet resistance of the large fan blade is reduced, and the effective air inlet area is increased. The end vortex-eliminating sealing device is a vortex-eliminating sealing plate and can also be a vortex-eliminating sealing rectangular pipe, a vortex-eliminating sealing triangle or a vortex-eliminating sealing arc, and when the vortex-eliminating sealing device is arranged in the mode that the two sides of the vortex-eliminating sealing arc are arranged in an outwards-protruding arc mode, the vortex-eliminating sealing device can be combined with the fan blade to form an integrated large fan blade.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of louver, especially relate to a big fan leaf type louver with flow channel end transverse vortex elimination for ventilation regulation. BACKGROUND

[0002] The wet cooling tower has different degrees of icing problem when running in winter, especially in the severe cold northern region. The most important icing parts are the air inlet, the wind cylinder support, the water spraying filler and the filler support beam. If corresponding measures are not taken in time, the air inlet icing will intensify and even form an ice curtain, resulting in reduced air inlet area and seriously affecting the cooling effect of the cooling tower. The current measures mainly include manually hanging a wind baffle at the air inlet and using a new anti-freezing louver. However, the water mist or floating water generated during the operation of the wet cooling tower will fall on the anti-freezing louver, causing icing on its surface and affecting the anti-freezing control of the equipment. In severe cases, the anti-freezing device will be damaged, affecting its safety.

[0003] At present, the louver fan leaves are mostly horizontally arranged and can be used for winter anti-freezing sealing of the cooling tower, while the louver is in a fully open state at other times. The horizontally arranged fan leaves of the fully open louver hinder the air inlet of the cooling tower to some extent, increase the air inlet resistance to a certain extent, reduce the overall air inlet volume, and cause the cooling performance of the tower to decrease. There are also vertical fan leaf louvers used for anti-freezing of the cooling tower, but the width of the louver fan leaves is small, resulting in too many louver fan leaves arranged around the air inlet of the cooling tower, which increases the air inlet resistance of the cooling tower, and the small width vertical fan leaves cannot play a role in guiding the wind when the louver is fully open. Therefore, a louver device for ventilation regulation needs to be designed, which can minimize the ventilation resistance of the louver fan leaves when the louver fan leaves are fully open in the non-anti-freezing season under the condition of meeting the sealing requirement for winter anti-freezing, and also can play a role in guiding the wind, increasing the overall air inlet volume and improving the cooling performance of the cooling tower when there is environmental wind.

[0004] Chinese patent application No. 202221988242.2 discloses a natural ventilation wet cooling tower with integrated vertical anti-freezing louvers, which comprises a natural ventilation wet cooling tower, a flow guide plate, and vertical anti-freezing louvers. The flow guide plate is located at the middle position between adjacent louvers and is installed perpendicularly to the louvers to improve the uniformity of the air inlet of the cooling tower. The vertical anti-freezing louvers can adjust the louver angle to change the air inlet area according to the ambient temperature and the wind speed of the air inlet direction, thereby adjusting the air inlet amount of the cooling tower. Although the vertical louvers have a certain flow guiding effect, the main flow guiding effect is achieved by the flow guide plate. The air guided by the flow guide plate needs to pass through the vertical louvers, thereby increasing the air inlet resistance and reducing the overall air inlet amount of the cooling tower, resulting in a decrease in the cooling efficiency of the cooling tower. In addition, the length of the flow guide plate is not clearly specified. When the length of the flow guide plate is too short, it has no flow guiding effect, and when the length is too long, it will cause large vortexes in the leeward side flow passage, increase the air inlet resistance, and reduce the effective air inlet area, thereby reducing the air guiding effect.

[0005] Chinese patent application No. 202221988204.7 discloses a natural ventilation wet cooling tower with integrated horizontal anti-freezing louvers, which comprises a natural ventilation wet cooling tower and integrated horizontal anti-freezing louvers. The integrated horizontal anti-freezing louvers are composed of a flow guide plate, a flow guide plate fixing device, an anti-freezing device structure frame, and horizontal louver anti-freezing units, which are arranged along the circumference of the cooling tower. The flow guide plate is located at the middle position between adjacent louvers and is installed perpendicularly to the louvers. When the temperature is high, the flow guide plate increases the uniformity of the air inlet of the cooling tower and improves the cooling efficiency of the cooling tower. When the temperature is low, the horizontal anti-freezing louvers can flexibly adjust the air inlet amount of each position of the cooling tower according to the ambient temperature and the wind speed of the air inlet direction, thereby reducing the possibility of local icing of the cooling tower under crosswind. This patent realizes anti-freezing and flow guiding by the flow guide plate and the horizontal louvers around the tower. However, in the non-anti-freezing working condition, the air inlet resistance of the horizontal louvers continuously affects the overall air volume, thereby reducing the cooling performance of the cooling tower. In addition, this patent does not specify the length of the flow guide plate.

[0006] Chinese patent application No. 201120033074.7 discloses a counter-flow natural ventilation cooling tower air inlet guide and anti-freezing wind screen integrated device. A certain number of air inlet guide and anti-freezing wind screen integrated devices are installed on the circumference of the air inlet at the bottom of the cooling tower, which includes a guide plate main body and wind screen blades movably connected to the guide plate main body. The wind screen blades and the guide plate main body are integrated to control and optimize the uniformity of the air flow field and the air inlet amount. In winter, the wind screen blades are rotated to prevent the cooling tower from freezing, replacing the traditional wind screen. According to the description of the guide plate, the main body is a rhombus with an acute angle of 75-80 degrees, the height is equal to the height of the air inlet, and the installation distance from the air inlet plane is 0-500 mm. Therefore, the length of the guide plate main body is the ratio of the height of the air inlet to the sine of the acute angle, which is greater than the height of the air inlet. However, the size of the guide plate main body is too long, which forms a large transverse vortex in the leeward side of the flow channel, thereby increasing the air inlet resistance and reducing the effective air inlet area.

[0007] The above patents propose to use louver ventilation control for winter freezing prevention at the air inlet of the cooling tower, and to use guide plate guide for flow field optimization at the air inlet of the cooling tower. The main shortcomings of the above patents are: 1. The size of the anti-freezing louver blade is too small. After installing the anti-freezing louver, even if the louver blade is fully opened, the effective air inlet area in the same air inlet space is reduced due to the thickness of the louver blade, thereby affecting the air inlet amount in non-freezing seasons such as spring, summer and autumn; 2. The radial size of the guide plate for flow field optimization at the air inlet is too large. When the environmental wind is affected, the guide plate is easy to induce a large transverse vortex on the leeward side while guiding the wind, thereby reducing the effective ventilation area between two adjacent guide plates and reducing the effective guide effect of the guide plate. SUMMARY

[0008] To solve the problems in the above-mentioned prior art, a large-blade louver for ventilation control is provided, which can eliminate the transverse vortex at the end of the flow channel.

[0009] The technical solution adopted by the present invention to solve its technical problems is: a large-blade type shutter that can eliminate the transverse vortex at the end of the flow channel for ventilation control, including a shutter frame and a large blade group, characterized in that: the shutter frame is a rectangular frame or a truss structure, which plays the role of installing and supporting the large blade group; the large blade group includes M vertically arranged large blades that can eliminate the transverse vortex at the end of the air inlet flow channel, where M is an integer from 1 to 12; the large blade that can eliminate the transverse vortex at the end of the air inlet flow channel includes an end vortex elimination sealing device, a fan blade, and a fan blade rotating shaft; the end vortex elimination sealing device is installed at the air inlet side end of the fan blade, and when the large blade group is fully open, it can optimize the flow field at the air inlet side end of the fan blade, reduce the transverse vortex at the end of the air inlet flow channel between it and the adjacent large blades, thereby reducing the additional air inlet resistance of the large blade and increasing the effective air inlet area; when the large blade group is fully closed, the end vortex elimination sealing device can improve the overall sealing performance of the large-blade type shutter.

[0010] The shutter frame is composed of a rectangular tube made of galvanized steel, stainless steel, fiberglass, aluminum alloy or other high-strength corrosion-resistant materials, or is composed of I-beams, H-shaped steels, channel steels or other profiles; the overall height Ht of the large fan blade that can eliminate the transverse vortex at the end of the air inlet flow channel is 1.0m~4.0m, the overall width Bt is 0.4m~2.0m, preferably 0.55m~1.65m, and the overall thickness is Wt; the overall width Bt and the overall thickness Wt of the large fan blade that can eliminate the transverse vortex at the end of the air inlet flow channel simultaneously satisfy a certain width-to-thickness ratio of 10:1≤Bt:Wt≤100:1.

[0011] The end vortex-eliminating sealing device is a vortex-eliminating sealing plate, which is installed at the air inlet side end of the fan blade; the height of the vortex-eliminating sealing plate is equal to the overall height Ht of the large fan blade that can eliminate the transverse vortex at the end of the air inlet flow channel, and the outward length from the air inlet side end of the large fan blade along the air outlet side end to the air inlet side end is Lt, and the value range is 0.15Wt ≤Lt≤1.5Wt; the vertical distance between the outer end of the leeward side of the vortex-eliminating sealing plate and the leeward side end face of the large fan blade is Dt, 0.15Wt≤Dt≤1.8Wt.

[0012] The end vortex-eliminating sealing device can also be a vortex-eliminating sealing rectangular tube, preferably a square tube, forming a stepped structure with the fan blade; the height of the vortex-eliminating sealing rectangular tube is equal to the overall height Ht of the large fan blade that can eliminate the transverse vortex at the end of the air inlet flow channel, and the outward length from the air inlet side end of the large fan blade along the air outlet side end to the air inlet side end is Lf, and the value range is 0.15Wt ≤Lf≤0.6Wt; the vertical distance between the leeward side end face of the vortex-eliminating sealing rectangular tube and the leeward side end face of the large fan blade is Df, and Df≥Lf.

[0013] The end vortex seal device can also be a vortex seal triangle, which utilizes a slope at the large fan blade air inlet side end to guide the air inlet, thereby reducing the transverse vortex at the air inlet flow channel end; the vortex seal triangle is installed at the fan blade air inlet side end and air outlet side end, thereby ensuring the overall sealing when the shutter is fully closed; the vortex seal triangle height is equal to the overall height Ht of the large fan blade, the length Ls from the air inlet side end of the large fan blade to the outside in the direction from the air outlet side end to the air inlet side end is 0.15Wt≤Ls≤1.5Wt; the vertical distance Ds from the outside end of the vortex seal triangle to the leeward side end surface of the large fan blade is 0.15Wt≤Ds≤Wt.

[0014] The end vortex seal device can also be a vortex seal triangle, which utilizes a slope at the large fan blade air inlet side end to guide the air inlet, thereby reducing the transverse vortex at the air inlet flow channel end; the vortex seal triangle is installed at the fan blade air inlet side end and air outlet side end, thereby ensuring the overall sealing when the shutter is fully closed; the vortex seal triangle height is equal to the overall height Ht of the large fan blade, the length Ls from the air inlet side end of the large fan blade to the outside in the direction from the air outlet side end to the air inlet side end is 0.15Wt≤Ls≤1.5Wt; the vertical distance Ds from the outside end of the vortex seal triangle to the leeward side end surface of the large fan blade is 0.15Wt≤Ds≤Wt.

[0015] On the basis of the end vortex seal device being installed at the fan blade air inlet side end, the end vortex seal device can further be installed at the fan blade air outlet side end, thereby rectifying the air outlet confluence on both sides of the windward side end surface and the leeward side end surface of the large fan blade.

[0016] The fan blade is a whole blade or a combined blade composed of a fan skeleton and a fan surface; the whole blade is a flat plate type blade; the fan skeleton comprises an outer frame and 1-20 inner supports; the fan surface is made of rigid materials such as profiled steel plates, color steel plates, etc., and is fixed on one or more of the windward side end surface and the leeward side end surface of the fan skeleton by welding or screw riveting; the fan surface can also be made of flexible materials such as PVC base cloth, knife scraping cloth, etc., or other high-strength flexible materials, and is fixed on one or more of the windward side end surface and the leeward side end surface of the fan skeleton by screws or pressing strips.

[0017] The vortex seal arc is divided into an inner concave arc structure and an outer convex arc structure; both the inner concave arc structure and the outer convex arc structure can be arranged on one side or on both sides; when the outer convex arc structure is arranged on both sides, the vortex seal arc can form an integrated structure with the fan blade by integral molding processing.

[0018] The fan rotating shaft is a solid cylinder or a thick-walled pipe with a diameter of 6-30 mm, made of stainless steel or other high-strength, corrosion-resistant and wear-resistant materials, and is fixed on the fan blade by welding or a fixing clamp; the fan rotating shaft is connected with the louver frame by adding a shaft sleeve at the upper end and a bearing or a shaft sleeve at the lower end, so that the fan blade can rotate vertically around the fan rotating shaft in the louver frame.

[0019] Compared with the prior art, the beneficial effects of the utility model are that: the utility model discloses a large-fan-leaf type louver capable of eliminating end flow channel transverse vortex for ventilation regulation, which can adapt to various working conditions and operating environments, including anti-freezing sealing in winter working conditions, air inlet flow guiding in side wind working conditions and the like, and guarantees the safe and normal operation of the cooling tower.

[0020] The end vortex elimination sealing device is installed at the air inlet side end of the fan blade, when the fan group is fully opened, the end vortex elimination sealing device at the end optimizes the flow field at the air inlet side end of the fan blade, reduces the transverse vortex at the end of the air inlet flow channel between the fan blade and the adjacent large fan blade, thereby effectively reducing the additional air inlet resistance of the large fan blade and increasing the effective air inlet area while guiding the air; when the fan group is fully closed, the end vortex elimination sealing device can be overlapped with the adjacent fan blade on the rotating side, thereby improving the overall sealing performance of the large fan-leaf type louver; on this basis, the end vortex elimination sealing device can also be installed at the air outlet side end of the fan blade, and the end vortex elimination sealing device can flow the air outlet on both sides of the air inlet side end surface and the leeward side end surface of the large fan blade, thereby further reducing the air inlet resistance, improving the overall air inlet amount and enhancing the cooling performance of the cooling tower. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 It is a large-fan-leaf type louver capable of eliminating end flow channel transverse vortex for ventilation regulation in a fully opened state.

[0022] Figure 2 It is a large-fan-leaf type louver capable of eliminating end flow channel transverse vortex for ventilation regulation in a fully closed state.

[0023] Figure 3 It is a large-fan-leaf structure schematic view in which the end vortex elimination sealing device is a vortex elimination sealing plate.

[0024] Figure 4 It is a structure size view of the vortex elimination sealing device being a vortex elimination sealing plate.

[0025] Figure 5 It is a large-fan-leaf structure schematic view in which the end vortex elimination sealing device is a vortex elimination sealing rectangular pipe.

[0026] Figure 6 It is a schematic view of the transverse vortex at the end of the air inlet flow channel between the lower fan blades without adding a vortex elimination sealing plate.

[0027] Figure 7 This is a schematic diagram of the flow field at the end of the air inlet duct between the large fan blades at different positions of the end vortex elimination seal device.

[0028] Figure 8 It is a schematic diagram of the structure of different types of end vortex elimination sealing devices.

[0029] Figure 9 This is a schematic diagram of the flow field with and without the vortex-eliminating sealing plate on the air outlet side of the fan blade.

[0030] Figure 10 It is a schematic diagram of the installation structure of the upper and lower ends of the fan blade rotating shaft.

[0031] In the figure: 1-louver frame; 2-large fan blade capable of eliminating transverse vortices at the end of the flow channel; 3-fan blade skeleton; 31-outer frame; 32-inner support; 4-fan surface; 5-fan blade rotating shaft; 51-shaft sleeve; 52-bearing; 6-end vortex elimination sealing device; 7-rotating shaft sealing device; 8-large fan blade air inlet side end; 9-large fan blade air outlet side end; 10-leeward side end face; 11-windward side end face; 12-leeward side of vortex elimination sealing plate; 13-outer end; 14-inlet flow channel end; 15-integrated large fan blade end vortex elimination structure; 16-integrated large fan blade. DETAILED DESCRIPTION

[0032] The present invention will be described in detail below with reference to the specific embodiments shown in the accompanying drawings. However, these embodiments do not limit the present invention, and any structural, methodological, or functional modifications made by a person skilled in the art based on these embodiments are all within the scope of protection of the present invention.

[0033] A large-blade shutter for ventilation control that can eliminate transverse vortices at the end of the flow channel comprises a shutter frame 1 and a large blade group, and is characterized in that: the shutter frame 1 is a rectangular frame or a truss structure, which serves to support the large blade group; the large blade group is composed of 5 vertically arranged large blades 2 that can eliminate transverse vortices at the end of the air inlet flow channel; the large blades 2 that can eliminate transverse vortices at the end of the air inlet flow channel include an end vortex-eliminating sealing device 6, a fan blade, and a fan blade rotating shaft 5; the end vortex-eliminating sealing device 6 is installed at the air inlet side end 8 of the fan blade.

[0034] like Figure 1 When the large fan blade 2 shown is fully opened, the end vortex-eliminating sealing device reduces the lateral vortex at the end of the air inlet flow channel between the fan blade and the adjacent large fan blade 2 by optimizing the flow field at the air inlet end of the fan blade, thereby effectively reducing the additional air inlet resistance and increasing the effective air inlet area while guiding the air from the large fan blade; Figure 2When the large fan leaf 2 is fully closed, the vortex-eliminating structure at the end of the fan blade can form an effective overlapping joint with the adjacent fan leaf on the rotating side, thereby improving the overall sealing of the large fan leaf type shutter; the vortex-eliminating sealing device 6 is also installed at the outflow side end 9 of the fan blade, and plays a flow rectifying role for the outflow of the large fan leaf on both sides.

[0035] The shutter frame 1 is made of galvanized steel pipe with a specification of 60*40*2.0mm.

[0036] The overall height Ht of the large fan leaf 2 is 2.0m, the overall width Bt is 1.0m, the overall thickness Wt is 40mm, and the width-thickness ratio is 25:1.

[0037] As shown in Figure 3 , Figure 4 , the vortex-eliminating sealing device 6 is a vortex-eliminating sealing plate installed at the inflow side end 8 of the fan blade, with a height of 2.0m and a length of Lt=25mm; the leeward side of the vortex-eliminating sealing plate is vertically spaced from the leeward side end surface 10 of the large fan leaf 2 by a distance Dt=Wt=40mm.

[0038] In addition, as shown in Figure 5 and Figure 8 , the vortex-eliminating sealing device 6 can also adopt a vortex-eliminating sealing rectangular tube, preferably a square tube structure, with a specification of 20*20*1.2mm galvanized square tube, installed at the inflow side end 8 and the outflow side end 9 of the fan blade, forming a stepped shape, with a length Lf=20mm from the inflow side end of the large fan leaf to the outflow side end in the direction of the outflow side end to the inflow side end, and a vertical distance Df=20mm from the leeward side end surface of the vortex-eliminating sealing rectangular tube to the leeward side end surface of the large fan leaf; when the fan leaf is closed, the vortex-eliminating sealing rectangular tubes overlap and joint together, thereby improving the sealing between the blades.

[0039] In addition, as shown in Figure 8 -(b), the vortex-eliminating sealing device 6 can also be a vortex-eliminating sealing triangle, which utilizes a bevel at the inflow side end 8 of the fan blade to guide the inflow, thereby reducing the transverse vortex at the end of the flow channel; the vortex-eliminating sealing triangle is installed at the inflow side end 8 and the outflow side end 9 of the fan blade, thereby ensuring the overall sealing of the shutter when it is fully closed; the height is 2.0m, the length Ls=Wt=40mm from the inflow side end of the large fan leaf to the outflow side end in the direction of the outflow side end to the inflow side end, and the vertical distance Ds=Wt=40mm from the outside end of the vortex-eliminating sealing triangle to the leeward side end surface of the large fan leaf.

[0040] As shown in Figure 8 -(c), Figure 8- (d) as shown, the end vortex seal device 6 can also be a vortex seal arc, which guides the air flow at the large fan blade 2 inlet side end 8 by arc surface, thereby reducing the transverse vortex at the end of the flow channel; the vortex seal arc is divided into an inner concave arc structure and an outer convex arc structure, wherein the inner concave arc structure is installed at the fan blade inlet side end 8, and the outer convex arc structure is installed at the fan blade outlet side end 9; the height is 2.0m, the length Ly=Wt=40mm from the inlet side end of the large fan blade to the outlet side end to the inlet side end, the vertical distance Dy=Wt=40mm from the outside end of the vortex seal arc to the leeward side end surface of the large fan blade.

[0041] Based on the installation of the end vortex seal device at the inlet side end of the fan blade, further, the end vortex seal device can also be installed at the outlet side end 9 of the fan blade, which can rectify the air flow on both sides of the large fan blade.

[0042] In addition, as shown in Figure 8 - (e) as shown, when the vortex seal arc is arranged on both sides of the outer convex arc, the vortex seal arc can form an integrated structure with the fan blade, and the integrated large fan blade is formed by integral molding, which is divided into an end vortex structure 15 and a blade 16.

[0043] The fan blade is an integrated blade, and the whole body is a flat plate type.

[0044] In addition, the fan blade can also be a combined blade composed of a fan skeleton and a fan surface; wherein the fan skeleton 3 is composed of an outer frame 31 and four inner supports 32; the fan surface 4 is fixed on the windward side end surface 11 of the fan skeleton 3 by means of a combination of screws and pressure strips; the flexible material is more light and easy, the self weight of the fan is reduced, the frictional resistance of the activity is reduced, and the stability of the operation is ensured.

[0045] The fan rotating shaft 5 is a solid round steel with a diameter of 15mm, made of stainless steel, and fixed on the fan blade by welding, so that the fan blade can rotate vertically around the fan rotating shaft in the shutter frame.

[0046] As shown in Figure 10 - (a) as shown, the upper end of the fan rotating shaft 5 is connected with the shutter frame 1 by adding a shaft sleeve 51, which ensures the vertical rotation of the fan; the shaft sleeve 51 is made of stainless steel, with a thickness of 1.0mm and a depth of 15mm.

[0047] As shown in Figure 10 - (b) as shown, the lower end of the fan rotating shaft 5 is connected with the shutter frame 1 by adding a thrust bearing 52, which reduces the frictional resistance caused by the self weight of the fan, further improves the rotation stability, and ensures the vertical rotation of the fan around the fan rotating shaft 5.

[0048] As shown in Figure 10The lower end of the fan rotating shaft 5 is provided with a sealing device 7, which improves the overall sealing performance of the large-fan shutter, as shown in (b).

[0049] The basic principle, main features and advantages of the present application are shown and described above, and it is obvious for those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic features of the present application; therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting, the scope of the present application is defined by the appended claims rather than the above description, and therefore all changes falling within the meaning and scope of the equivalent elements of the claims should be included in the present application, and any reference signs in the claims should not be regarded as limiting the claims.

[0050] In addition, it should be understood that, although the present application is described in terms of embodiments, not every embodiment contains only one independent technical solution, and the description of the specification is only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in the examples can also be properly combined to form other embodiments that those skilled in the art can understand.

Claims

1. A large-blade louver for ventilation control capable of eliminating transverse vortices at the end of a flow channel, comprising a louver frame and a large-blade assembly, characterized in that: The shutter frame is a rectangular frame or a truss structure, which serves to install and support the large fan blade group; the large fan blade group includes M vertically arranged large fan blades that can eliminate the transverse vortex at the end of the air inlet flow channel, where M is an integer from 1 to 12; the large fan blade that can eliminate the transverse vortex at the end of the air inlet flow channel includes an end vortex elimination sealing device, a fan blade, and a fan blade rotating shaft; the end vortex elimination sealing device is installed at the air inlet side end of the fan blade, and when the large fan blade group is fully open, it can optimize the flow field at the air inlet side end of the fan blade, reduce the transverse vortex at the end of the air inlet flow channel between it and the adjacent large fan blade, thereby reducing the additional air inlet resistance of the large fan blade and increasing the effective air inlet area; when the large fan blade group is fully closed, the end vortex elimination sealing device can improve the overall sealing of the large fan blade type shutter.

2. A large-blade louver for ventilation control capable of eliminating transverse vortices at the end of the flow passage according to claim 1, characterized in that: The shutter frame is composed of a rectangular tube made of galvanized steel, stainless steel, fiberglass or aluminum alloy, or is composed of I-beams, H-shaped steels or channel steels; the overall height Ht of the large fan blades that can eliminate the transverse vortex at the end of the air inlet flow channel is 1.0m~4.0m, the overall width Bt is 0.4m~2.0m, and the overall thickness is Wt; the overall width Bt and the overall thickness Wt of the large fan blades that can eliminate the transverse vortex at the end of the air inlet flow channel simultaneously satisfy a certain width-to-thickness ratio of 10:1≤Bt:Wt≤100:

1.

3. A large-blade louver for ventilation control capable of eliminating transverse vortices at the end of the flow passage according to claim 2, characterized in that: The end vortex-eliminating sealing device is a vortex-eliminating sealing plate, which is installed at the air inlet side end of the fan blade; the height of the vortex-eliminating sealing plate is equal to the overall height Ht of the large fan blade that can eliminate the transverse vortex at the end of the air inlet flow channel, and the outward length from the air inlet side end of the large fan blade along the air outlet side end to the air inlet side end is Lt, and the value range is 0.15Wt ≤Lt≤1.5Wt; the vertical distance between the outer end of the leeward side of the vortex-eliminating sealing plate and the leeward side end face of the large fan blade is Dt, 0.15Wt≤Dt≤1.8Wt.

4. A large-blade louver for ventilation control capable of eliminating transverse vortices at the end of the flow passage according to claim 3, characterized in that: The end vortex-eliminating sealing device can also be a vortex-eliminating sealing rectangular tube, forming a stepped structure with the fan blade; the height of the vortex-eliminating sealing rectangular tube is equal to the overall height Ht of the large fan blade that can eliminate the transverse vortex at the end of the air inlet flow channel, and the outward length from the air inlet side end of the large fan blade along the air outlet side end to the air inlet side end is Lf, and the value range is 0.15Wt≤Lf≤0.6Wt; the vertical distance between the leeward side end face of the vortex-eliminating sealing rectangular tube and the leeward side end face of the large fan blade is Df, and Df≥Lf.

5. A large-blade louver for ventilation control capable of eliminating transverse vortices at the end of the flow passage according to claim 4, characterized in that: The end vortex-eliminating sealing device can also be a vortex-eliminating sealing triangle, which uses an inclined surface at the end of the air inlet side of the large fan blade to guide the incoming air, thereby reducing the lateral vortex at the end of the air inlet flow channel; the vortex-eliminating sealing triangle is installed at the air inlet side end and the air outlet side end of the fan blade to ensure the overall sealing when the shutter is fully closed; the height of the vortex-eliminating sealing triangle is equal to the overall height Ht of the large fan blade, and the outward length from the air inlet side end of the large fan blade along the air outlet side end to the air inlet side end is Ls, and the value range is 0.15Wt≤Ls≤1.5Wt; the vertical distance between the outer end of the vortex-eliminating sealing triangle and the leeward end face of the large fan blade is Ds, 0.15Wt≤Ds≤Wt.

6. A large-blade louver for ventilation control capable of eliminating transverse vortices at the end of the flow passage according to claim 5, characterized in that: The end vortex-eliminating sealing device can also be a vortex-eliminating sealing arc, which uses the arc surface at the end of the air inlet side of the large fan blade to guide the incoming air, thereby reducing the lateral vortex at the end of the air inlet flow channel; the height of the vortex-eliminating sealing arc is equal to the overall height Ht of the large fan blade, and the outward length Ly from the air inlet side end of the large fan blade along the air outlet side end to the air inlet side end is in the range of 0.15Wt≤Ly≤1.5Wt; the vertical distance between the outer end of the vortex-eliminating sealing arc and the leeward end face of the large fan blade is Dy, 0.15Wt≤Dy≤Wt.

7. The large-blade shutter for ventilation control capable of eliminating transverse vortices at the end of the flow passage according to claim 3, characterized in that: On the basis of the end vortex-eliminating sealing device being installed at the end of the air inlet side of the fan blade, the end vortex-eliminating sealing device can further be installed at the end of the air outlet side of the fan blade to rectify the air outlet convergence on both sides of the windward side end face and the leeward side end face of the large fan blade.

8. The large-blade shutter for ventilation control capable of eliminating transverse vortices at the end of the flow passage according to claim 1, characterized in that: The fan blade is an integral blade, or a combined blade consisting of a fan blade frame and a fan surface; the integral blade is a flat blade; the fan blade frame includes an outer frame and 1 to 20 internal supports; the fan surface is made of rigid material and is fixed to one or more of the windward side end faces and the leeward side end faces of the fan blade frame by welding or riveting; the fan surface can also be made of flexible material and fixed to one or more of the windward side end faces and the leeward side end faces of the fan blade frame by screws or strips.

9. The large-blade shutter for ventilation control capable of eliminating transverse vortices at the end of the flow passage according to claim 6, characterized in that: The vortex-eliminating seal arc is divided into an inner concave arc structure and an outer convex arc structure; the inner concave arc structure and the outer convex arc structure can be arranged on one side or on both sides; When the outward convex arc structure is arranged on both sides, the vortex-eliminating seal arc can form an integrated structure with the fan blades through an integrated molding process.

10. The large-blade shutter for ventilation control capable of eliminating transverse vortices at the end of the flow passage according to claim 1, characterized in that: The fan blade rotating shaft is a solid cylinder or thick-walled round tube with a diameter of 6mm~30mm, made of stainless steel, and fixed to the fan blade by welding or fixing clamps; the fan blade rotating shaft is connected to the shutter frame by adding a shaft sleeve at the upper end and a bearing or shaft sleeve at the lower end to ensure that the fan blade can rotate vertically around the fan blade rotating shaft within the shutter frame.

Images