Blades of cross-flow wind wheel, cross-flow wind wheel and air conditioner

Abstract

The blade is an arc-shaped plate, the two ends, in the radial direction of the cross-flow wind wheel, of the blade are the front edge and the rear edge, the front edge is close to the axis of the cross-flow wind wheel, the two opposite sides of the blade are the pressure side and the suction side, and the surfaces of the two corresponding sides of the blade are the pressure face and the suction face respectively. The middle part of the blade protrudes towards the suction side, and the front edge and the rear edge of the blade extend towards the pressure side; wherein the part, close to the front edge, of the blade forms at least one bent section bent towards the pressure side, the bent section is a concave area on the suction surface, and the bent section is a convex area on the pressure surface; the most protruding point of each protruding area, the front edge and the rear edge can form an arc line, and the middle of the arc line protrudes towards the suction side. According to the blade of the cross-flow wind wheel, the utilization rate of airflow is high, and generated noise is low.

Description

Technical Field

[0001] The present invention relates to the field of crossflow wind wheels, and in particular to a blade of a crossflow wind wheel, a crossflow wind wheel having the blade, and an air conditioner using the crossflow wind wheel. Background Art

[0002] Traditional crossflow impellers generally use single arc blades or thin airfoil blades. The blade design is single and has certain limitations in air supply efficiency, resulting in poor control of the main airflow by the blades and excessive aerodynamic noise. The crossflow impeller does not have an ideal wind energy utilization rate.

[0003] Some existing technical solutions also propose thickened crossflow rotor blades, which improve the airflow condition by thickening the outer edge of the blades, or superimpose a slot design on the basis of thickening. Thickening the blades will cause the overall weight of the crossflow rotor to be too large, occupying too many airflow channels. The increase in wind resistance caused by thickening the blades may offset the reduction in wind resistance brought about by the improvement of the blade profile, and may ultimately lead to unsatisfactory improvement in wind energy utilization.

[0004] Therefore, there is room for improvement in the blades of the crossflow impeller. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a blade of a crossflow impeller, wherein the blade has a high utilization rate of airflow and generates little noise.

[0006] The present invention further proposes a crossflow wind wheel having blades of the crossflow wind wheel.

[0007] The invention also provides an air conditioner with a cross-flow fan wheel.

[0008] According to a blade of a crossflow wind wheel in an embodiment of the first aspect of the present invention, the blade is an arc-shaped plate, and the two ends of the blade along the radial direction of the crossflow wind wheel are a leading edge and a trailing edge, the leading edge is adjacent to the axis of the crossflow wind wheel, the opposite sides of the blade are a pressure side and a suction side, the corresponding two side surfaces of the blade are a pressure surface and a suction surface, respectively, the blade is convex toward the suction side in the middle part, and the leading edge and the trailing edge extend toward the pressure side; wherein, the part of the blade adjacent to the leading edge forms at least one curved section curved toward the pressure side, the curved section is a concave area on the suction surface, and the curved section is a convex area on the pressure surface; the most convex point of each of the convex areas can construct a circular arc line with the leading edge and the trailing edge, and the middle of the circular arc line is convex toward the suction side.

[0009] According to a blade of a crossflow wind wheel according to an embodiment of the present invention, the two ends of the blade along the radial direction of the crossflow wind wheel are the leading edge and the trailing edge, and the corresponding two side surfaces of the blade are the pressure surface and the suction surface respectively. By setting a curved section at the leading edge of the blade, and the curved section forms a concave area on the suction surface, when air enters from the leading edge side of the blade, it passes through the curved section of the leading edge. When passing through the blade, the air starts from the suction surface and moves away from the suction surface. The airflow is the boundary layer and the outer mainstream in sequence. The boundary layer airflow is subject to the viscous resistance of the solid boundary wall, which reduces the flow velocity. The closer the flow velocity of the mainstream is to the boundary layer, the greater the resistance it encounters. Therefore, the overall airflow velocity is slower, and the greater the viscosity of the suction surface of the blade, the stronger the friction noise generated.

[0010] By setting the curved section, the airflow in the boundary layer close to the suction surface is affected by the vortex of the curved section, and a small vortex is formed in the recessed area. The small vortex destroys the airflow in the boundary layer, thereby reducing the viscosity of the low-speed boundary layer on the mainstream. Similarly, the boundary layer of the airflow passing through the pressure surface is also affected by the vortex of the curved section, which destroys the viscosity between the boundary layer and the wall surface of the pressure surface of the blade, thereby reducing the friction between the mainstream and the two sides of the blade, thereby increasing the flow velocity of the mainstream and improving the utilization rate of the airflow by the blade. Moreover, when the mutual friction between the airflow and the blade surface is reduced, the interaction force between the airflow molecules and the molecules on the surface of the object is gradually weakened, thereby achieving the effect of reducing noise.

[0011] Moreover, the curved section is used to reduce the influence of the vortex group on the main airflow, and can be adapted to blades of various blade shapes. It has good adaptability, wide application, good manufacturability, and is also helpful in avoiding the problem of excessive weight of the crossflow impeller.

[0012] According to some embodiments of the present invention, the blades of the crossflow wind wheel include one or two curved sections in the radial direction.

[0013] According to some embodiments of the present invention, the blade of the crossflow wind wheel includes a curved section in the radial direction;

[0014] The total chord length of the blade is L0, and the distance between the leading edge and the curved section is L1, satisfying 0.20≤L1 / L0≤0.39.

[0015] According to some embodiments of the present invention, in the blades of the crossflow wind wheel, the chord length of the curved section is L2, which satisfies 0.12≤L2 / L0≤0.25.

[0016] According to some embodiments of the present invention, the blade of the crossflow wind wheel includes at least two curved sections in the radial direction;

[0017] The total chord length of the blade is L0, and the distance between the leading edge and the nearest curved section is L1, satisfying 0.12≤L1 / L0≤0.30.

[0018] According to some embodiments of the present invention, in the blades of the crossflow wind wheel, the chord length of the curved section is L2, which satisfies 0.20≤L2 / L0≤0.36.

[0019] According to some embodiments of the present invention, the blades of the crossflow wind wheel have a thickness T, and 0.8 mm ≤ T ≤ 1.1 mm.

[0020] According to some embodiments of the present invention, the blade of the crossflow wind wheel has a profile radius of the leading edge of R1, 0.6 mm ≤ R1 ≤ 0.8 mm;

[0021] The profile radius of the trailing edge is R2, 0.5mm≤R2≤0.7mm.

[0022] According to some embodiments of the present invention, the blades of the crossflow impeller are sheet metal parts or integrally injected fiberglass parts.

[0023] According to the second embodiment of the present invention, the crossflow wind wheel comprises: two end plates and blades connected between the two end plates, wherein the blades are the blades of the crossflow wind wheel according to the first embodiment of the present invention. By providing the blades, the wind resistance and noise of the crossflow wind wheel are reduced and the efficiency is improved.

[0024] The air conditioner according to the third embodiment of the present invention comprises the crossflow impeller according to the first embodiment of the present invention. The crossflow impeller is provided to reduce the operating noise of the air conditioner and improve the efficiency.

[0025] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0027] Figure 1 is a schematic diagram of a crossflow impeller of some embodiments;

[0028] Figure 2 is a schematic diagram of blades of a crossflow wind wheel according to some embodiments of the present application;

[0029] Figure 3 is another schematic diagram of a blade of a crossflow wind wheel according to some embodiments of the present application;

[0030] Figure 4 is a schematic diagram of blades of a crossflow wind wheel according to other embodiments of the present application;

[0031] Figure 5 is another schematic diagram of blades of a crossflow wind wheel according to other embodiments of the present application.

[0032] Reference numerals:

[0033] Crossflow wind wheel 1000, blade 10, leading edge 11, leading edge profile radius R1, trailing edge 12, trailing edge profile radius R2, pressure surface 13, suction surface 14, curved section 15, recessed area 151, raised area 152, most convex point p, arc line Z, total chord length L0 of blade, distance L1 between leading edge and curved section of blade, chord length L2 of curved section, blade thickness T, axis Y, end plate 20,

[0034] Inter-blade channel 30, air inlet end 31, air outlet end 32, pressure side 3a, suction side 3b. DETAILED DESCRIPTION

[0035] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0036] In the description of the present invention, it should be understood that the terms "center", "thickness", "upper", "lower", "front", "back", "inner", "outer", "radial", "axial", "circumferential" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0037] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] The crossflow impeller 1000 and the blade 10 according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

[0039] Specific reference Figure 1The crossflow wind wheel 1000 includes an end plate 20 and a plurality of blades 10 connected to the end plate 20. The crossflow wind wheel 1000 has an axis Y, and the plurality of blades 10 are distributed around the axis Y. Usually, the crossflow wind wheel 1000 is connected to a driving motor, and the driving motor drives the crossflow wind wheel 1000 to rotate when it is running, and the axis Y is also the rotation center line of the crossflow wind wheel 1000.

[0040] like Figure 1 As shown, the direction parallel to the axis Y is referred to as the axial direction herein. The direction around the axis Y is referred to as the circumferential direction herein, that is, the plurality of blades 10 are spaced apart and distributed along the circumferential direction. The direction perpendicular to the axis Y is referred to as the radial direction herein, and each blade 10 is generally arranged to extend in the radial direction. Of course, in the present application, the blade 10 is not a straight plate arranged in the radial direction, but an arc-shaped plate.

[0041] Specifically, Figure 2 As shown, an inter-blade channel 30 is formed between two adjacent blades 10 spaced apart along the circumferential direction. The technical improvement of the present invention lies in the improvement of the shape of the blades 10. The driving principle and the characteristics of the airflow direction of the crossflow impeller 1000 when it is in operation are well known to those skilled in the art. Therefore, only the following will be described here. Figure 1 and Figure 2 Taking the crossflow impeller 1000 shown in the figure as an example, the influence of the crossflow impeller 1000 on the airflow during rotation in some embodiments is briefly described to understand the influence of the shape improvement of the blade 10 on the airflow drive. Figure 1 and Figure 2 As shown, when the crossflow impeller 1000 rotates, the inner end of the inter-blade channel 30 (i.e., the end facing the axis Y) forms a negative pressure to inhale the airflow, and the outer end of the inter-blade channel 30 (i.e., the end away from the axis Y) forms a high pressure, and drives the airflow in the inter-blade channel 30 radially outward, and the inner end of the inter-blade channel 30 becomes the air inlet end 31, and the outer end of the inter-blade channel 30 becomes the air outlet end 32. Of course, the present application does not exclude that in some solutions, the inner end of the inter-blade channel 30 becomes the air outlet end 32, and the outer end of the inter-blade channel 30 becomes the air inlet end 31. The following only takes the inner end of the inter-blade channel 30 as the air inlet end 31 and the outer end as the air outlet end 32 as an example for explanation.

[0042] Correspondingly, the two ends of the blade 10 along the radial direction of the crossflow wind wheel 1000 are the leading edge 11 and the trailing edge 12. The leading edge 11 is the end of the blade 10 close to the axis Y of the crossflow wind wheel 1000, and the trailing edge 12 is the end of the blade 10 away from the axis Y of the crossflow wind wheel 1000. The opposite sides of the blade 10 are the pressure side 3a and the suction side 3b, and the corresponding two side surfaces of the blade 10 are the pressure surface 13 and the suction surface 14, respectively. In other words, one side of the blade 10 pushes the airflow in the inter-blade channel 30 on both sides in the circumferential direction, and the air pressure on this side rises during operation, and this side surface is called the pressure surface 13. The other side of the blade 10 in the circumferential direction is away from the airflow in the inter-blade channel 30, and the air pressure on this side decreases during operation, and this side surface is called the suction surface 14.

[0043] In order to match the function of the blade 10 of the crossflow wind wheel 1000, the blade 10 is constructed as an arc-shaped plate, the blade 10 is convex toward the suction side 3b in the middle part, and the leading edge 11 and the trailing edge 12 extend toward the pressure side 3a. With such a design, the blade 10 is in an embracing position relative to the airflow on the pressure side 3a, which is conducive to the blade 10 further squeezing the airflow on the pressure side 3a to raise the pressure on the pressure side 3a, thereby forming a driving force for driving the airflow to flow.

[0044] The arc design of the blade 10 can increase the torsional rigidity and strength of the blade 10, so that it can better resist the effect of wind force, and can also reduce wind resistance. The arc design can also make the aerodynamic characteristics of the blade 10 more stable, reduce noise and vibration, extend the service life of the blade 10, and improve the efficiency and reliability of wind energy utilization.

[0045] It can be understood that the airflow is sucked into the inter-blade channel 30 from the inner end of the blade 10, and the airflow is equivalent to being split head-on by the leading edge 11 of the blade 10, and is divided into two streams entering the inter-blade channels 30 on both sides of the blade 10. When the airflow flows out from the outer end of the blade 10, it is equivalent to the airflows of the inter-blade channels 30 on both sides flowing out and merging along the trailing edge 12 of the blade 10. Therefore, the airflow has flow direction changes of divergence and merging at the leading edge 11 and the trailing edge 12 of the blade 10.

[0046] Due to the viscosity of the airflow on the surface of the blade 10, the airflow velocity in the surface area of ​​the blade 10 is lower the closer to the surface of the blade 10. The blade 10 is an arc-shaped plate as a whole. When the airflow flows along the curved surface, the velocity change gradient of the airflow along the normal direction at different points on the curved surface is different. And because there is a pressure difference in the tangential direction at different points on the curved surface, especially at the leading edge 11 and the trailing edge 12, it is very easy to generate tiny vortex groups on the surface of the blade 10. The formation of vortex groups will not only occupy the flow space of the normal airflow in the inter-blade channel 30, but also generate friction with the normal airflow, which will lead to a decrease in the utilization rate of wind energy, affect the driving efficiency of the crossflow wind wheel 1000, and generate unnecessary loud noise.

[0047] The prior art has proposed to increase the thickness of the blades to reduce the generation of vortex groups on the blade surface. That is, by using the larger leading edge radius and trailing edge radius at both ends of the thickened blades, the airflow is smoother when it is split and merged, so as to reduce the vortex groups. However, this type of blade is too thick, resulting in the weight of the wind wheel increasing by more than 30% compared to ordinary impellers. In addition, this type of blade requires the crossflow wind wheel aspect ratio to be greater than 6. The excessive weight of the wind wheel makes it difficult to control the dynamic balance and vibration in the middle, and the actual production and manufacturing are more difficult and costly. Some other schemes propose to thicken the blades and set a depression on the pressure surface. The shortcoming of this scheme is that the blade as a whole still needs to be thickened. The overall weight of the crossflow wind wheel is still increased due to the arrangement of multiple blades. The wind wheel is still too heavy, making it difficult to control the dynamic balance and vibration in the middle. The elimination of vortex groups is limited to the pressure surface.

[0048] To solve the above problems, the present application proposes a blade 10 of a crossflow impeller 1000, such as Figure 2 and Figure 3 As shown, a portion of the blade 10 adjacent to the leading edge 11 forms at least one curved section 15 curved toward the pressure side 3 a . The curved section 15 is a concave area 151 on the suction surface 14 , and is a convex area 152 on the pressure surface 13 .

[0049] With the continuous development of bionics and aerodynamic design, the inventor team has gained inspiration from the morphology and functions of many natural organisms. For example, the bending structure of the leading edge of the wings of insects such as dragonflies and bees shows good performance in fluid dynamics and can efficiently control the airflow. In the prior art, the blade is usually an arc plate, which is arranged at the wind outlet. As the airflow passes through the pressure surface and suction surface on both sides of the blade, the airflow forms a boundary layer near the solid boundary wall of the blade. The airflow velocity in this boundary layer is significantly smaller than the mainstream velocity. The boundary layer will also drag the mainstream velocity, so that the overall airflow velocity is reduced. However, this defect cannot be improved by increasing the airflow velocity. When the airflow velocity increases, the thickness of the boundary layer will also increase, and the obstruction effect will also increase. Secondly, the airflow passes through the solid boundary wall of the blade, causing the airflow to generate friction resistance. This resistance not only consumes the energy of the airflow, reduces the velocity of the airflow, but also generates noise. The present application sets a curved section 15 near the leading edge 11 of the blade 10, which is similar to the bending structure of the leading edge of the wings of natural organisms, and can obtain good mechanical performance, which can overcome the above weaknesses.

[0050] Reference Figure 2, the concave area 151 formed by the curved section 15 on the suction surface 14 will change the flow velocity of the airflow in the boundary layer on the side of the suction surface 14. The most convex point p of each convex area 152 can form an arc line Z with the leading edge 11 and the trailing edge 12, and the middle of the arc line Z bulges toward the suction side 3b. In this way, the center position of the concave area 151 formed on the suction surface 14 is within the boundary layer. When the fluid in the boundary layer encounters the concave area 151, it will flow to the center position of the concave area 151, forming a local low-pressure area, resulting in an increase in the flow velocity in the boundary layer. The mainstream adjacent to the boundary layer is less affected by the boundary layer, so that the flow velocity of the mainstream can be significantly improved.

[0051] Reference Figure 2 The curved section 15 is a raised area 152 on the pressure surface 13, which will also change the flow velocity of the airflow in the boundary layer on the pressure surface 13. When the airflow encounters the raised area 152, it will flow upward and leave the boundary layer. Since there is no obstruction from the solid boundary, these airflows can continue to flow upward without being subject to the friction resistance of the boundary layer. Therefore, the flow velocity of the boundary layer will increase accordingly, and the corresponding adjacent mainstream flow velocity will also increase relatively. At the same time, this boundary layer separation also effectively reduces the friction between the airflow and the side of the blade 10, reducing noise.

[0052] In addition, the inventor team also found that the size of the depression area 151 will also affect the flow velocity of the boundary layer. A smaller depression area 151 may lead to a smaller boundary layer separation, which is conducive to increasing the flow velocity and reducing the noise. A larger depression area 151 will produce a local high-pressure area at the depression. The fluid in this high-pressure area is more likely to generate vortices, which will cause the fluid flow in the high-pressure area to be more unstable, and correspondingly increase the resistance to the mainstream, reduce the overall flow velocity of the airflow, and the unstable flow of the fluid will cause friction with the surrounding blades and the mainstream to produce greater noise.

[0053] The raised part will also affect the flow velocity of the boundary layer. Specifically, when the airflow flows through the raised part, the streamline is bent and rubbed, causing the flow velocity to slow down. At the same time, the raised part will form an airflow vortex. The larger the protrusion, the larger the airflow vortex. The larger vortex will roll up the boundary layer and cover it upward to form a backflow. At this time, the backflow direction is exactly opposite to the mainstream direction. Therefore, not only the flow velocity of the mainstream is reduced, but the friction between the backflow and the mainstream will also generate greater noise.

[0054] It should be noted that the inventor team learned from the silent flight characteristics of some eagles, such as ospreys and owls, that their airfoils have good aerodynamic performance. For example, the bending structure of owl wings can act as a vortex generator, which disperses large air vortices passing through the surface of the wings into small and fine vortices, suppresses the generation of boundary layer noise, consumes the energy of aerodynamic noise, and thus reduces the noise generated by the contact between the wings and the airflow.

[0055] Therefore, the inventor team adjusted the size of the raised area 152 and the recessed area 151 to make the airflow obtain a more favorable boundary layer separation. By setting the most convex point p of each raised area 152 to form an arc line Z with the leading edge 11 and the trailing edge 12, the middle of the arc line Z is raised toward the suction side 3b, ensuring that the convexity of the raised area 152 transitions evenly on the arc line Z, and effectively controlling the airflow vortex formed by the raised part. For the recessed area 151, the acceleration of the boundary layer passing through the recessed area 151 is tangent to the direction of the mainstream when it flows out of the recessed area 151, reducing the friction resistance of the mainstream, increasing the overall flow velocity of the airflow, and reducing the friction noise between the airflow and the blade 10.

[0056] In the present application, by bending a part of the blade 10 toward the pressure side 3a, there is no need to thicken the blade 10, which is conducive to keeping the overall weight of the crossflow wind wheel 1000 not too heavy. Moreover, after such a design, the blade 10 as a whole still embraces the airflow on the pressure side 3a, which is conducive to the blade 10 squeezing the airflow on the pressure side 3a to raise the pressure on the pressure side 3a. At the same time, bending a part of the blade 10 toward the pressure side 3a will cause the blade 10 to form a depression toward the suction side 3b, and the blade 10 will also form a depression toward the pressure side 3a, and the number of depressions toward the pressure side 3a is greater than the number of depressions toward the suction side 3b, which can match the amount of vortex generated by the blade 10 on the pressure side 3a and the suction side 3b.

[0057] In addition, the provision of the curved section 15 in the present application can also increase the torsional rigidity and strength of the blade 10, reduce deformation or damage after being subjected to force, and further reduce wind resistance and noise. Moreover, the curved section 15 is used to reduce the influence of the vortex group on the main airflow, and can be adapted to blades of various blade shapes, with good adaptability, wide application, good manufacturability, and also conducive to avoiding the problem of excessive weight of the crossflow impeller.

[0058] In some embodiments, the blade 10 is a curved plate with uniform thickness, which is easy to process and requires low assembly positioning accuracy. In addition, the use of a curved plate with uniform thickness does not require thickening at a certain location to improve the airflow vortex problem, which is conducive to maintaining the overall thinness of the blade 10 and reducing weight.

[0059] Here, the thickness T of the blade 10 is relatively uniform, which means that the thickness of the portion of the blade 10 between the leading edge 11 and the trailing edge 12 is relatively uniform, and the difference in thickness T between the two locations does not exceed 10%.

[0060] Specifically, in the present application, the blade 10 is an arc-shaped plate, and the blade 10 may be located on the same arc except for the curved section 15, or may be composed of multiple arcs.

[0061] Specifically, refer to Figure 3 , Figure 5, setting the thickness of the blade 10 to T, satisfying 0.8mm≤T≤1.1mm, for example, the thickness of the blade 10 is 0.8mm, 0.9mm, 1.0mm, 1.05mm, 1.1mm, etc. Here, the thickness T of the blade 10 is controlled to at least 0.8mm, which can ensure that the blade 10 has sufficient structural rigidity and strength, and avoid deformation due to being too thin or too soft. By controlling the thickness T of the blade 10 to not more than 1.1mm, it is beneficial to prevent the blade 10 from occupying too much of the inter-blade channel 30, so that the blade 10 can make more use of the pressure surface 13 to pressurize the airflow and use the suction surface 14 to attract the airflow. The thinner blade 10 is more likely to split the airflow at the leading edge 11, and the thinner blade 10 makes the airflow change less in direction when it merges at the trailing edge 12.

[0062] Of course, the present application does not exclude that in other embodiments, in order to improve the accuracy of controlling the flow direction of the airflow, the blade 10 may be thickened at a local position.

[0063] In some embodiments, Figure 2 and Figure 4 As shown, the blade 10 includes one or two curved segments 15 in the radial direction. In this way, the number of curved segments 15 is limited, which is conducive to controlling the size of the curved segments 15 in the radial direction of the blade 10 (i.e., the chord length L2 of the curved segments 15), and is conducive to controlling the influence of the curved segments 15 on the airflow. This is conducive to maintaining the overall shape of the blade 10 without requiring a major change, and the driving influence of the blade 10 on the airflow as a whole does not change much when the crossflow impeller 1000 rotates.

[0064] The overall blade shape of the blade 10 designed in this way can adopt the blade shape of the crossflow wind wheel that has been maturely applied in the prior art, such as the blade shape of a single arc blade, or the blade shape of a thin airfoil blade, and then the curved section 15 is processed on the basis of the existing mature blade shape. In this way, the design difficulty of the blade 10 in the design stage can be reduced, and many analysis and experimental results of the existing mature blades can be inherited. In the processing stage of the blade 10, the processing production line of the existing blade can be used, and the processing cost is also greatly reduced.

[0065] Of course, it is not excluded that in some solutions, by controlling the deformation amount of the bending segment 15 , the number of the bending segments 15 can be increased, such as three or four bending segments 15 .

[0066] The blades 10 of the crossflow wind wheel 1000 according to some embodiments of the present invention are shown in FIG. Figure 2 and Figure 3 The blade 10 includes a curved section 15 in the radial direction.

[0067] Reference Figure 3, the total chord length of the blade 10 is set to L0, and the distance between the leading edge 11 and the curved section 15 is set to L1. In the range of L1, the curvature of the blade 10 is small, and the ratio of the distance to the total chord length satisfies 0.20≤L1 / L0≤0.39. For example, L1 / L0 is equal to 0.20, 0.22, 0.25, 0.28, 0.30, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37, 0.38, 0.39, 0.315, 0.345, etc.

[0068] Such a design makes the curved section 15 close to the leading edge 11 but not too close. The distance L1 between the leading edge 11 and the curved section 15 is limited to at least 20% of the total chord length L0 of the blade 10. The blade 10 has a smooth arc section from the leading edge 11 to the curved section 15, which is conducive to the smooth splitting of the airflow by the blade 10 when it first enters the inter-blade channel 30. The airflow smoothly enters the inter-blade channel 30 from the air inlet end 31, and the airflow of the pressure surface 13 in this section can flow with the mainstream, reducing the formation of vortices. After the mainstream is formed and stabilized, the generated vortex flows into the depressions on the two surfaces along the pressure surface 13 and the suction surface 14. The vortex is blocked here, and the mainstream fluid still flows to the outer end.

[0069] By limiting the distance L1 between the leading edge 11 and the curved section 15 to not more than 39% of the total chord length L0 of the blade 10, the purpose is to avoid the curved section 15 being too far away from the leading edge 11, thereby reducing the length of the vortex flow path and limiting the vortex to be quickly stopped in the recess, so that the destructive force of the vortex on the mainstream can be effectively controlled.

[0070] In some embodiments, reference Figure 3 The blade 10 includes a curved section 15 in the radial direction, the total chord length of the blade 10 is L0, the chord length of the curved section 15 is L2, and 0.12≤L2 / L0≤0.25 is satisfied. For example, L2 / L0 is equal to 0.12, 0.15, 0.16, 0.18, 0.20, 0.21, 0.22, 0.23, 0.24, 0.25, 0.185, 0.235, etc.

[0071] Thus, the overall chord length L2 of the curved section 15 can be controlled not to be too short on the blade 10, thereby ensuring the blocking and limiting effect of the curved section 15 on the vortex group. In addition, the overall chord length L2 of the curved section 15 will not be too long on the blade 10, which is conducive to the overall blade shape of the blade 10 not changing much compared with when there is no curved section 15.

[0072] In some specific examples, the sound source of the bionic blade profile is about 7% lower than that of the conventional blade profile at the same wind volume. The curved section 15 effectively reduces the friction resistance of the blade 10 to the airflow, thereby reducing the noise of the crossflow impeller 1000.

[0073] The blades 10 of the crossflow wind wheel 1000 according to some embodiments of the present invention are shown in FIG. Figure 4 and Figure 5 The blade 10 includes at least two curved sections 15 in the radial direction.

[0074] Reference Figure 5 , the total chord length of the blade 10 is set to L0, and the distance between the leading edge 11 and the nearest curved section 15 is set to L1, satisfying 0.12≤L1 / L0≤0.30. For example, L1 / L0 is equal to 0.12, 0.13, 0.15, 0.18, 0.20, 0.21, 0.25, 0.27, 0.30, 0.155, 0.215, 0.2855, etc.

[0075] In this way, when the number of curved sections 15 exceeds one, the curved section 15 is appropriately moved forward. With such a design, the curved section 15 is close to the leading edge 11 but not too close. Among them, the distance L1 between the leading edge 11 and the curved section 15 is limited to at least 12% of the total chord length L0 of the blade 10, and the blade 10 still has a smooth arc section from the leading edge 11 to the curved section 15, which is conducive to the airflow being smoothly split by the blade 10 when it first enters the inter-blade channel 30. The airflow smoothly enters the inter-blade channel 30 from the air inlet end 31, and the airflow on its pressure surface 13 in this section can flow with the mainstream, reducing the formation of vortices. After the mainstream is formed and stabilized, the generated vortex flows into the depressions on the two surfaces along the pressure surface 13 and the suction surface 14. The vortex is blocked here, and the mainstream fluid still flows to the outer end.

[0076] By limiting the distance L1 between the leading edge 11 and the curved section 15 to not more than 30% of the total chord length L0 of the blade 10, the purpose is to avoid the curved section 15 being too far away from the leading edge 11, thereby reducing the length of the vortex flow path and limiting the vortex to be quickly stopped in the recess, so that the destructive force of the vortex on the mainstream can be effectively controlled.

[0077] In some embodiments, reference Figure 5 , set the chord length of the curved section 15 to L2, and the total chord length of the blade 10 to L0, satisfying 0.20≤L2 / L0≤0.36. For example, L2 / L0 is equal to 0.20, 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.28, 0.30, 0.33, 0.36, etc. In this way, the overall chord length L2 of the two curved sections 15 on the blade 10 can be controlled not to be too short, ensuring the blocking and limiting effect of the curved section 15 on the vortex group. Moreover, the overall chord length L2 of the curved section 15 on the blade 10 will not be long, which is conducive to the overall blade shape of the blade 10 not changing much compared with when there is no curved section 15.

[0078] In some embodiments, reference Figure 3 , Figure 5, the profile radius of the leading edge 11 is set to R1. When the thickness T of the blade 10 satisfies 0.8mm≤T≤1.1mm, the profile of the leading edge 11 satisfies 0.6mm≤R1≤0.8mm. In this way, the profile radius R1 of the leading edge 11 is set close to the thickness T of the blade 10, so that the leading edge 11 is sufficiently convex and rounded at the end facing the axis Y, which is conducive to the smooth cutting of the airflow by the leading edge 11.

[0079] Specifically, the radius of the profile of the trailing edge 12 is set to R2, satisfying 0.5 mm ≤ R2 ≤ 0.7 mm. It can be understood that the airflow merges at the trailing edge 12, and after the radius of the profile of the trailing edge 12 is restricted as described above, the trailing edge 12 is sufficiently convex and rounded at the outward end, which is conducive to the smooth flow and convergence of the airflow along the trailing edge 12.

[0080] Furthermore, the radius R2 of the profile of the trailing edge 12 is different from the radius R1 of the profile of the leading edge 11 .

[0081] According to some embodiments of the present invention, the blades 10 of the crossflow wind wheel 1000 are sheet metal parts. From the processing point of view, due to the high processing accuracy of the sheet metal parts, the accuracy requirements of the bending section 15 can be met. Moreover, the blades 10 processed by the sheet metal parts are light in weight, which can increase the rotation rate of the blades 10, and reduce the weight of the entire crossflow wind wheel 1000, reduce energy consumption, and benefit environmental protection. At the same time, the sheet metal parts are easy to process, can be processed quickly, and improve production efficiency. Specifically, by bending the materials of corresponding sizes, the curved plates and the curved sections 15 on the curved plates are formed, so that they are bent into corresponding curvatures. The bending processes include but are not limited to suspended bending, in-mold bending, flip bending, etc., so that the processed blades 10 meet the technical requirements.

[0082] In some embodiments, optionally, the blade 10 is an integrally-injected fiberglass part. The relative density of fiberglass is low, but the tensile strength of fiberglass itself is close to that of carbon steel. Therefore, the blade 10 is made of fiberglass, which is light in weight and requires low energy consumption, which correspondingly reduces the energy consumption of the crossflow impeller 1000, and is more energy-saving and environmentally friendly. The raw materials of the fiberglass part include glass fiber and resin. The raw materials are heated, melted, and mixed into a liquid, and the raw material liquid is injected into the mold, and the raw material liquid is waited for to solidify to form the curved shape of the blade 10, so that the blade 10 can be customized according to the different shapes of the arc plate and the curved section 15, and finally demolded to form a blade 10 that meets the size requirements, so that the high plasticity is strong, which is conducive to meeting the processing requirements. The integrally-injected fiberglass part reduces the generation of bubbles and defects, and can improve the quality of the blade 10. The fiberglass blade 10 also has excellent corrosion resistance, ensuring a longer service life.

[0083] Optionally, the fiberglass parts used in the blade 10 include, but are not limited to, AS, ABS or PP plastic plus glass fiber high-strength composite parts.

[0084] Of course, the present application does not exclude the possibility that the blade 10 is made of a high-strength lightweight material, such as a high-strength lightweight plastic.

[0085] The crossflow impeller 1000 according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

[0086] According to other embodiments of the present invention, the crossflow impeller 1000 is as follows: Figure 1 As shown, the crossflow impeller 1000 comprises an end plate 20 and a blade 10 connected to the end plate 20, and the blade 10 adopts the blade 10 of the crossflow impeller 1000 in the above embodiment. The structure of the blade 10 has been described above and will not be repeated here. By providing the above blade 10, it is beneficial to control the overall weight of the crossflow impeller 1000, improve the utilization rate of the airflow, improve efficiency and reduce noise.

[0087] According to some other embodiments of the present invention, the air conditioner comprises a cross flow fan 1000. The cross flow fan 1000 is the cross flow fan 1000 in the above embodiment.

[0088] Other components of the blades 10 of the crossflow wind wheel 1000 according to the embodiment of the present invention, such as the crossflow wind wheel 1000 and the air conditioner and the operation thereof, are well known to those skilled in the art and will not be described in detail here.

[0089] First embodiment

[0090] Please refer to the attached Figure 2-Figure 3 , describing the blade 10 of the crossflow wind wheel 1000 according to the first embodiment of the present application.

[0091] The blade 10 is an arc-shaped plate, and includes a leading edge 11 , a trailing edge, a pressure surface 13 and a suction surface 14 .

[0092] The leading edge 11 and the trailing edge are two ends spaced apart along the radial direction of the crossflow wind wheel 1000, the leading edge 11 is close to the axis Y of the crossflow wind wheel 1000, and the leading edge 11 is far away from the axis Y of the crossflow wind wheel 1000. In the wind outlet direction, the leading edge 11 and the trailing edge are respectively in the wind inlet area 30 and the wind outlet area 31.

[0093] The opposite sides of the blade 10 are the pressure side 3a and the suction side 3b, and the corresponding two side surfaces of the blade 10 are the pressure surface 13 and the suction surface 14 respectively. The blade 10 bulges toward the suction side 3b in the middle part, and the leading edge 11 and the trailing edge extend toward the pressure side 3a.

[0094] The portion of the blade 10 adjacent to the leading edge 11 forms a curved section 15 that curves toward the pressure side 3a, the curved section 15 forms a recessed area 151 on the suction surface 14, and the curved section 15 is a convex area 152 on the pressure surface 13. The most convex point p of the convex area 152 can form an arc line Z with the leading edge 11 and the trailing edge 12, and the middle of the arc line Z convexes toward the suction side 3b.

[0095] The total chord length of the blade 10 is L0, the distance between the leading edge 11 and the curved section 15 is L1, which satisfies 0.20≤L1 / L0≤0.39; the chord length of the curved section 15 is L2, which satisfies 0.12≤L2 / L0≤0.25.

[0096] The thickness of the blade 10 is T, which satisfies 0.8 mm ≤ T ≤ 1.1 mm.

[0097] The profile radius of the leading edge 11 is R1, satisfying 0.6 mm ≤ R1 ≤ 0.8 mm; the profile radius of the trailing edge 12 is R2, satisfying 0.5 mm ≤ R2 ≤ 0.7 mm.

[0098] Second embodiment

[0099] Please refer to the attached Figure 4-Figure 5 , describing the blade 10 of the crossflow wind wheel 1000 according to the second embodiment of the present application.

[0100] The blade 10 is an arc-shaped plate, and includes a leading edge 11 , a trailing edge, a pressure surface 13 and a suction surface 14 .

[0101] The blade 10 of this embodiment is basically the same as that of the first embodiment, and is also a curved plate, and also includes a leading edge 11, a trailing edge, a pressure surface 13 and a suction surface 14. The opposite sides of the blade 10 are also a pressure side 3a and a suction side 3b. The difference is that the portion of the blade 10 adjacent to the leading edge 11 forms two curved sections 15 that are curved toward the pressure side 3a.

[0102] The total chord length of the blade 10 is L0, the distance between the leading edge 11 and the nearest curved section 15 is L1, satisfying 0.12≤L1 / L0≤0.30; the chord length of the curved section 15 is L2, satisfying 0.20≤L2 / L0≤0.36.

[0103] In the description of this specification, the description with reference to the terms "embodiment", "example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0104] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A blade of a crossflow impeller, characterized in that: The blade is an arc-shaped plate, and the two ends of the blade along the radial direction of the crossflow wind wheel are the leading edge and the trailing edge, the leading edge is close to the axis of the crossflow wind wheel, the opposite sides of the blade are the pressure side and the suction side, the corresponding two side surfaces of the blade are the pressure surface and the suction surface respectively, the blade is convex toward the suction side in the middle part, and the leading edge and the trailing edge extend toward the pressure side; Wherein, a portion of the blade adjacent to the leading edge forms at least one curved section curved toward the pressure side, the curved section being a concave area on the suction surface, and the curved section being a convex area on the pressure surface; The most convex point of each of the convex areas can form an arc line with the leading edge and the trailing edge, and the middle of the arc line convexes toward the suction side.

2. The blade of the crossflow impeller according to claim 1, characterized in that: The blade is an arc-shaped plate with uniform thickness, and the blade includes one or two curved sections along the radial direction.

3. The blade of the crossflow impeller according to claim 1, characterized in that: The blade includes a curved section in the radial direction; The total chord length of the blade is L0, and the distance between the leading edge and the curved section is L1, satisfying 0.20≤L1 / L0≤0.

39.

4. The blade of the crossflow impeller according to claim 3, characterized in that: The chord length of the curved section is L2, satisfying 0.12≤L2 / L0≤0.

25.

5. The blade of the crossflow impeller according to claim 1, characterized in that: The blade includes at least two curved segments in the radial direction; The total chord length of the blade is L0, and the distance between the leading edge and the nearest curved section is L1, satisfying 0.12≤L1 / L0≤0.

30.

6. The blade of the crossflow impeller according to claim 5, characterized in that: The chord length of the curved section is L2, satisfying 0.20≤L2 / L0≤0.

36.

7. The blade of the crossflow wind wheel according to any one of claims 1 to 6, characterized in that: The blade thickness is T, 0.8 mm ≤ T ≤ 1.1 mm.

8. The blade of the crossflow impeller according to claim 7, characterized in that: The profile radius of the leading edge is R1, 0.6mm≤R1≤0.8mm; The profile radius of the trailing edge is R2, 0.5mm≤R2≤0.7mm.

9. The blade of the crossflow wind wheel according to any one of claims 1 to 6, characterized in that: The blade is a sheet metal part or an integrally-injected glass fiber reinforced plastic part.

10. A crossflow impeller, characterized in that: include: At least two end plates, and blades connected between the two end plates, wherein the blades are blades of a crossflow wind wheel according to any one of claims 1-9.

11. An air conditioner, characterized in that: The invention comprises the crossflow impeller as claimed in claim 10.

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