Vortex generator, shape design method thereof and blade

Abstract

The invention discloses a vortex generator, a shape design method thereof and a blade, and the vortex generator comprises a base which is provided with a top surface and a bottom surface which are oppositely arranged in a first direction; the fins are arranged on the top face and protrude out of the top face in the first direction, in the first direction, the outer contour of the cross section of any position of each fin comprises a trailing edge line and streamline curves arranged in pairs, and the streamline curves arranged in pairs are symmetrically distributed relative to the first axis in the second direction. Each streamline curve comprises a first curve section and a second curve section which are sequentially arranged in the third direction, the first curve section is an arc section, and in the third direction, the vertical distance from the second curve section to the first axis tends to be increased firstly and then decreased. By the adoption of the vortex generator, the purposes of effectively reducing the resistance coefficient and increasing the vortex strength can be achieved while the structural strength of the vortex generator is guaranteed, and therefore boundary layer separation is effectively delayed.

Description

Technical Field

[0001] The present invention relates to the technical field of vortex generators, and in particular to a vortex generator and a shape design method and blades thereof. Background Art

[0002] Competition in the wind power industry is becoming increasingly fierce, and the demand for large-scale wind turbines and cost reduction is becoming increasingly urgent. Large wind turbine blades generally use thick special airfoils from the middle to the root to increase the structural strength of the blades. Such thick airfoil blades are prone to flow separation. Vortex generators can effectively suppress turbulent boundary layer separation by improving the flow morphology of the turbulent boundary layer, achieving higher lift and lower drag, thereby improving the efficiency of wind turbines.

[0003] At present, the cross-section of the vortex generator fin is usually a slender rectangle. As the vortex generator increases in size as the blade shape increases, the cross-sectional width of the fin must increase in order to ensure the structural strength of the vortex generator. However, increasing the cross-sectional width of the fin will increase the drag coefficient of the vortex generator, reduce the vortex strength, and inhibit the boundary layer separation effect. Summary of the invention

[0004] The embodiment of the present invention provides a vortex generator and its shape design method and blade. By adopting a special streamlined shape of the vortex generator fin shape design, it is possible to effectively reduce the drag coefficient and increase the vortex strength while ensuring the structural strength of the vortex generator, thereby effectively delaying the boundary layer separation.

[0005] In a first aspect, an embodiment of the present invention provides a vortex generator, which includes: a base, having a top surface and a bottom surface relatively arranged in a first direction; a fin, which is arranged on the top surface and protrudes from the top surface along the first direction, wherein in the first direction, the outer contour of the cross-section of the fin at any position includes a trailing edge line and streamlined curves arranged in pairs, the streamlined curves arranged in pairs are symmetrically distributed relative to a first axis in a second direction, each streamlined curve includes a first curve segment and a second curve segment arranged successively along a third direction, the first curve segments arranged in pairs converge to a leading edge point at one end of the second curve segment away from the third direction, and the second curve segments arranged in pairs are spaced from each other at one end of the first curve segment away from the third direction and are respectively connected to the trailing edge line; wherein the first curve segment is an arc segment, and along the third direction, the vertical distance from the second curve segment to the first axis shows a trend of first increasing and then decreasing, and the first direction, the second direction and the third direction are arranged to intersect with each other.

[0006] In a possible implementation manner of the first aspect, a vertical distance from the leading edge point to the trailing edge line along the third direction is H, and a span of the first curved segment in the third direction is h1, where h1≤5%H.

[0007] In a possible implementation of the first aspect, the perpendicular distance from the leading edge point to the trailing edge line in the third direction is H, and the distance from the projection point of the point with the maximum perpendicular distance to the first axis on the first axis in the second direction to the leading edge point on the second curve segment is h2, where 40%H ≤ h2 ≤ 60%H.

[0008] In a possible implementation of the first aspect, the perpendicular distance from the leading edge point to the trailing edge line in the third direction is H, and the perpendicular distance between the two end points of the trailing edge line in the second direction is h3, where 3%H ≤ h3 ≤ 30%H.

[0009] In a possible implementation of the first aspect, two or more positioning holes are respectively arranged on both sides of the base in the second direction, and the two or more positioning holes on the same side are spaced apart in the third direction. In the second direction, each positioning hole on one side of the base is symmetrically distributed with respect to the center of the base with one positioning hole on the other side.

[0010] In a possible implementation of the first aspect, each positioning hole is provided with a mark, and the marks of every two symmetrically distributed positioning holes are the same.

[0011] In a possible implementation of the first aspect, the included angle between the connection line of the two symmetrically distributed positioning holes on the base and the third direction is θ, where 3° ≤ θ ≤ 40°.

[0012] In a possible implementation of the first aspect, a groove is provided on the base, and the groove is recessed from the bottom surface along the first direction toward the side where the top surface is located.

[0013] In a possible implementation of the first aspect, the bottom surface is an arc surface and is concave toward the top surface along the first direction.

[0014] In a possible implementation of the first aspect, the connection point of the first curve segment and the second curve segment on the same side in the third direction is continuous based on the first-order partial derivative.

[0015] In a possible implementation of the first aspect, the second curve segment and the end of the trailing edge line on the same side in the third direction are connected by an arc transition.

[0016] In a possible implementation of the first aspect, the second curve segment is generated by a polynomial function.

[0017] In the second aspect, an embodiment of the present invention provides a blade, which includes: a blade body; and a vortex generator as described above, and the base of the vortex generator is installed on the blade body.

[0018] In a possible implementation of the second aspect, there are multiple vortex generators and they are distributed at intervals along the axial direction of the blade body, and one end of two adjacent vortex generators on the same side along the third direction are converged towards each other, and the other ends are dispersed away from each other.

[0019] In a third aspect, an embodiment of the present invention provides a shape design method for the vortex generator as described above, the shape design method comprising:

[0020] determining a cross-sectional outer contour of a fin of a vortex generator;

[0021] The outer contour of the cross section is lofted to obtain the outer shape of the fin;

[0022] Designing a base on the shape of the fin to obtain the initial shape of the vortex generator;

[0023] Simulate the initial shape of the vortex generator;

[0024] When the simulation results meet the preset end conditions, the initial shape is determined as the final shape of the vortex generator.

[0025] In a possible implementation of the third aspect, when the simulation results do not meet the preset end conditions, the shape design method also includes: correcting the initial shape of the vortex generator; simulating the corrected shape until the simulation results meet the preset end conditions; and determining the corrected shape corresponding to the simulation results as the final shape of the vortex generator.

[0026] In a possible implementation of the third aspect, the simulation results include a vortex flow simulation value and a drag coefficient simulation value, and the preset end condition is used to indicate that the vortex flow simulation value is greater than or equal to a preset vortex flow threshold and the drag coefficient simulation value is less than or equal to a preset drag coefficient threshold.

[0027] The vortex generator in the embodiment of the present invention, the outer contour of the cross-section at any position of the fin includes a trailing edge line and streamlined curves arranged in pairs, the streamlined curves arranged in pairs are symmetrically distributed relative to the first axis in the second direction, each streamlined curve includes a first curve segment and a second curve segment arranged successively along the third direction, the first curve segments arranged in pairs converge to a leading edge point at one end of the third direction away from the second curve segment, the second curve segments arranged in pairs are spaced from each other at one end of the third direction away from the first curve segment and are respectively connected to the trailing edge line, wherein the first curve segment is an arc segment, and along the third direction, the vertical distance from the second curve segment to the first axis tends to first increase and then decrease.

[0028] Since the leading edge position of the fin of the vortex generator in the embodiment of the present invention adopts an arc curve design, it can improve the strength of the leading edge position of the fin while reducing the windward resistance, which is beneficial to improving the overall strength of the fin. And since the entire side surface of the fin from the leading edge to the trailing edge adopts a continuous streamline curve design, on the one hand, it can reduce the windward resistance, and on the other hand, the thickness of the fin first increases and then decreases. Even if the thickness of the thickest part of the fin is relatively large, there will be no problem of the overall large thickness of the fin. Thus, it can take into account the structural requirements, vortex intensity, and aerodynamic performance requirements of the vortex generator, so that during the process of the vortex generator increasing with the increase of the blade shape, it can ensure high structural strength and achieve the purpose of reducing the drag coefficient and increasing the vortex intensity, thereby effectively delaying the boundary layer separation. Brief Description of the Drawings

[0029] The present invention can be better understood from the following description of the specific embodiments in conjunction with the drawings. Among them, the same or similar reference numerals represent the same or similar features.

[0030] Figure 1 Structural schematic diagram of the vortex generator provided by the embodiment of the present invention;

[0031] Figure 2 Schematic diagram of the cross-sectional outer contour of the fin provided by the embodiment of the present invention;

[0032] Figure 3 Cross-sectional comparison diagram of the fins of the vortex generator provided by the embodiment of the present invention and the traditional vortex generator;

[0033] Figure 4 Schematic diagram of the CFD simulation result of the vortex generator provided by the embodiment of the present invention;

[0034] Figure 5 Schematic diagram of the CFD simulation result of the traditional vortex generator;

[0035] Figure 6 For Figure 2 Schematic diagram of the size of the corresponding cross-sectional outer contour;

[0036] Figure 7 Installation schematic diagram of two adjacent vortex generators on the blade provided by the embodiment of the present invention;

[0037] Figure 8 For Figure 1 Schematic diagram of the bottom structure of the corresponding vortex generator;

[0038] Figure 9 Gluing schematic diagram between the traditional vortex generator and the blade surface;

[0039] Figure 10Schematic diagram of adhesion between the vortex generator provided by the embodiment of the present invention and the blade surface;

[0040] Figure 11 One of the longitudinal section contour schematic diagrams of the vortex generator provided by the embodiment of the present invention;

[0041] Figure 12 Another longitudinal section contour schematic diagram of the vortex generator provided by the embodiment of the present invention;

[0042] Figure 13 The third longitudinal section contour schematic diagram of the vortex generator provided by the embodiment of the present invention;

[0043] Figure 14 Flowchart of the external shape design method of the vortex generator provided by an embodiment of the present invention;

[0044] Figure 15 Flowchart of the external shape design method of the vortex generator provided by another embodiment of the present invention.

[0045] Explanation of reference numerals:

[0046] 10 - Base; 101 - Groove; 102 - Positioning hole, 20 - Fin; 201 - Trailing edge line;

[0047] 202 - Streamlined curve; S1 - First curve segment; S2 - Second curve segment;

[0048] L1 - First axis, O - Leading edge point. Detailed implementation manners

[0049] The features and exemplary embodiments of various aspects of the present invention will be described in detail below. In the following detailed description, many specific details are set forth in order to provide a comprehensive understanding of the present invention.

[0050] The embodiment of the present invention provides a vortex generator. The fins of the vortex generator adopt a special streamlined external shape design, which can effectively reduce the drag coefficient and increase the vortex intensity while ensuring the structural strength of the vortex generator, and further effectively delay the boundary layer separation.

[0051] As Figure 1 shown, the vortex generator provided by the embodiment of the present invention includes a base 10 and fins 20. The base 10 has a top surface and a bottom surface oppositely arranged in the first direction; the fins 20 are arranged on the top surface and protrude from the top surface along the first direction.

[0052] As Figure 2As shown, in the first direction, the outer contour of the cross section of the fin 20 at any position includes a trailing edge line 201 and a pair of streamlined curves 202. The pair of streamlined curves 202 are symmetrically distributed relative to the first axis L1 in the second direction. Each streamlined curve 202 includes a first curve segment S1 and a second curve segment S2 that are successively arranged along the third direction. The paired first curve segments S1 converge to the leading edge point O at one end of the third direction away from the second curve segment S2, and the paired second curve segments S2 are spaced apart from each other at one end of the third direction away from the first curve segment S1 and are respectively connected to the trailing edge line 201.

[0053] In some optional embodiments, the connection point of the first curve segment S1 and the second curve segment S2 on the same side along the third direction can be continuous based on the first-order partial derivative, ensuring a smooth transition at the connection between the first curve segment S1 and the corresponding second curve segment S2, which is conducive to the smooth flow of gas along the side surface of the fin 20.

[0054] In some optional embodiments, the second curved segment S2 and the end of the trailing edge line 201 on the same side of the third direction may be connected by an arc transition. For example, a chamfer may be provided at the connection between the second curved segment S2 and the corresponding end of the trailing edge line 201 to provide a transitional drainage function for the gas flowing from the leading edge to the trailing edge.

[0055] The first curve segment S1 is an arc segment. The first curve segment S1 can be understood as a circumscribed arc segment passing through the leading edge point O, with the center of the circle being on the first axis L1. The expression of the circumscribed circle function is as follows:

[0056]

[0057] Among them, R 0 is the radius.

[0058] Compared with general curved structures, circular arc structures are more stable. The vortex generator in the embodiment of the present invention adopts a circular arc curve design at the leading edge of the fin 20, which can reduce the headwind resistance while increasing the strength of the leading edge of the fin 20, which is beneficial to improving the overall strength of the fin 20.

[0059] Along the third direction, the perpendicular distance from the second curve segment S2 to the first axis L1 first increases and then decreases. That is, in the embodiment of the present invention, after the arc segment at the leading edge position, the entire side surface of the vortex generator fin 20 from the leading edge to the trailing edge direction adopts a continuous streamline curve 202 design. On the one hand, it can reduce the windward resistance. On the other hand, the thickness of the fin 20 first increases and then decreases. Even if the thickness of the thickest part of the fin 20 is relatively large, there will be no problem of the overall large thickness of the fin 20. Therefore, it can take into account the structural requirements and aerodynamic performance requirements of the vortex generator. When the vortex generator increases with the increase of the blade shape, it can ensure high structural strength and at the same time achieve the purpose of reducing the drag coefficient and increasing the vortex strength, and can effectively delay the boundary layer separation.

[0060] In some alternative embodiments, the second curve segment S2 can be generated by a polynomial function, and the embodiment of the present invention does not limit the order of the polynomial. Taking a sixth-order polynomial function as an example, the function expression of the second curve segment S2 is as follows:

[0061]

[0062] where a i is an adjustment coefficient, and the streamline shape can be adjusted by changing a i to obtain a more optimal shape suitable for the vortex generator.

[0063] It should be noted that the above-mentioned first direction, second direction, and third direction intersect with each other. Exemplarily, the above-mentioned first direction, second direction, and third direction can be perpendicular to each other, or the included angles between them are close to 90°.

[0064] Figure 3 The left figure in shows the special streamline cross-sectional shape of the vortex generator fin 20 in the embodiment of the present invention. Figure 3 The right figure in shows the slender rectangular cross-sectional shape of the ordinary transverse vortex generator fin 20. It can be seen that the cross-section of the vortex generator fin 20 in the embodiment of the present invention is generally in a streamline curve 202, having the advantages of larger thickness and stronger structural strength, and is suitable for large-sized vortex generators.

[0065] Figure 4 shows the CFD vorticity simulation results of the vortex generator adopting the special streamline cross-sectional shape in the embodiment of the present invention. Figure 5 shows the CFD vorticity simulation results of the vortex generator adopting the slender rectangular cross-sectional shape. It can be seen that compared with Figure 5 Figure 4The denser the streamlines in it are, the higher the vortex intensity excited by the vortex generator of the embodiment of the present invention is, which can inject more energy into the boundary layer, thereby delaying the separation of the boundary layer. Moreover, the vortex generator with the special streamlined outer contour cross-section of the embodiment of the present invention has a lower drag coefficient. It can be known through CFD calculation that the drag coefficient is reduced by more than 10% compared with the rectangular fin.

[0066] As described above, in the vortex generator of the embodiment of the present invention, the outer contour of the cross-section at any position of the fin 20 includes a trailing edge line 201 and paired streamlined curves 202. The paired streamlined curves 202 are symmetrically distributed with respect to the first axis L1 in the second direction. Each streamlined curve 202 includes a first curve segment S1 and a second curve segment S2 successively arranged in the third direction. The paired first curve segments S1 converge to the leading edge point O at one end away from the second curve segment S2 in the third direction. The paired second curve segments S2 are spaced apart at one end away from the first curve segment S1 in the third direction and are respectively connected to the trailing edge line 201. Among them, the first curve segment S1 is an arc segment. Along the third direction, the perpendicular distance from the second curve segment S2 to the first axis L1 first increases and then decreases.

[0067] Since the leading edge position of the fin 20 of the vortex generator in the embodiment of the present invention adopts an arc curve design, it can reduce the windward resistance while improving the strength of the leading edge position of the fin 20, which is beneficial to improving the overall strength of the fin 20. And because the entire side surface of the fin 20 from the leading edge to the trailing edge direction adopts a continuous streamlined curve design, on the one hand, it can reduce the windward resistance, and on the other hand, the thickness of the fin 20 first increases and then decreases. Even if the thickness of the thickest part of the fin 20 is relatively large, there will be no problem of the overall large thickness of the fin 20. Thus, it can take into account the structural requirements, vortex intensity and aerodynamic performance requirements of the vortex generator, so that during the process of the vortex generator increasing with the increase of the blade shape, it can ensure a relatively high structural strength and at the same time achieve the purpose of reducing the drag coefficient and increasing the vortex intensity, thereby effectively delaying the separation of the boundary layer.

[0068] In some alternative embodiments, refer to Figure 6 , the perpendicular distance from the leading edge point O to the trailing edge line 201 in the third direction is H. H can also be understood as the chord length of the outer contour of the cross-section with a streamlined shape. The span of the first curve segment S1 in the third direction is h1, and the value of h1 satisfies the expression: h1 ≤ 5%H, that is, the length of the arc segment can be limited within 5% of the chord length to improve the structure and aerodynamic performance of the leading edge position of the fin 20 of the vortex generator.

[0069] In some alternative embodiments, refer to Figure 6, the distance from the projection point of the point on the second curve segment S2 with the maximum vertical distance to the first axis L1 along the second direction to the leading edge point O on the first axis L1 is h2, and the value of h2 satisfies the expression: 40%H ≤ h2 ≤ 50%H, that is, the position of the thickest part of the fin 20 is limited between 40% and 60% of the chord length. This position range is located in the middle area of the fin 20 along the length direction, avoiding the center of gravity of the fin 20 from shifting forward or backward, and can improve the structural stability of the fin 20.

[0070] In some alternative embodiments, referring to Figure 6 , the vertical distance between the two end points of the trailing edge line 201 in the second direction is h3, and the value of h3 satisfies the expression: 3%H ≤ h3 ≤ 30%H, that is, the trailing edge thickness of the fin 20 is limited within 30% of the chord length. The trailing edge thickness of the fin 20 within this thickness range can effectively increase the vortex intensity, reduce the drag coefficient, and increase the blade structure strength. Excessive or too small thickness will break the balance between the structural requirements and functional requirements of the vortex generator.

[0071] In some alternative embodiments, as Figure 7 shown, two or more positioning holes 102 are respectively provided on both sides of the base 10 of the vortex generator in the second direction. Two or more positioning holes 102 on the same side are spaced apart in the third direction. In the second direction, each positioning hole 102 on one side of the base 10 is symmetrically distributed with respect to the center of the base 10 with one positioning hole 102 on the other side.

[0072] Since the effect of a single vortex generator is limited, it is usually necessary to install multiple vortex generators at intervals along the blade length direction on the blade suction surface. Figure 7 shows the installation scenario of two adjacent vortex generators on it. It can be seen that one end of two adjacent vortex generators on the same side in the third direction converges towards each other, and the other end diverges away from each other, that is, two adjacent vortex generators are not arranged in parallel, but are arranged at a certain angle. During specific implementation, installers need to use an angle measuring tool to determine the installation position of the vortex generator. For large blades, it is very inconvenient to carry out the angle measurement work.

[0073] In the embodiment of the present invention, by providing positioning holes 102 on both sides of the base 10 of the vortex generator, and making each positioning hole 102 on one side of the base 10 symmetrically distributed with respect to the center of the base 10 with one positioning hole 102 on the other side. In this way, only by adjusting the angle of the vortex generator so that the connection line of the two centrally symmetric positioning holes 102 is parallel to the blade length direction, the installation effect of any vortex generator can reach the predetermined angle, which is very convenient.

[0074] In some alternative embodiments, referring to Figure 7, the included angle between the connection line of two symmetrically distributed positioning holes 102 on the base 10 and the third direction can be θ, and θ satisfies the expression: 3° ≤ θ ≤ 40°. That is to say, the installation angle of the vortex generator on the suction surface of the blade can be adjusted within the range of 3° to 40°. The combination of vortex generators within this angle range can effectively increase the vortex intensity, reduce the drag coefficient, and effectively delay the boundary layer separation.

[0075] Further, referring to Figure 7 , for the convenience of installers, marks can also be set for each positioning hole 102, so that the marks of every two symmetrically distributed positioning holes 102 are the same. In this way, only by adjusting the angle of the vortex generator to make the connection line of two positioning holes 102 with the same number parallel to the blade length direction, any vortex generator can achieve the installation effect at a predetermined angle.

[0076] In some alternative embodiments, as Figure 8 shown, a groove 101 can be provided on the base 10 of the vortex generator. The groove 101 is recessed from the bottom surface along the first direction towards the side where the top surface is located. Generally, the vortex generator needs to be fixed to the suction surface of the blade by an adhesive bonding method. The groove 101 in the embodiment of the present invention can be used to store glue, thereby increasing the contact area between the vortex generator and the blade, and enabling the vortex generator to be stably fixed on the blade surface.

[0077] Figure 9 shows the bonding structure between the traditional vortex generator and the blade, Figure 10 shows the bonding structure between the vortex generator in the embodiment of the present invention and the blade. It can be seen that the groove 101 of the base 10 of the vortex generator in the embodiment of the present invention can accommodate the adhesive bonding glue, can increase the contact area between the base 10 of the vortex generator and the blade, and can effectively control the thickness of the adhesive bonding glue.

[0078] In some alternative embodiments, the bottom surface of the vortex generator base can be an arc surface, and the arc surface is concave towards the top surface along the first direction. Figure 11 shows the vortex generator with a flat bottom surface designed. As a comparison, Figure 12 shows the vortex generator with an arc-shaped bottom surface designed. Among them, when designing the arc surface angle, the actual curvature of the blade surface can be referred to. It can be seen that by making a curvature treatment on the bottom surface of the base 10, it can be closer to the blade surface, which is beneficial to the uniform distribution of the adhesive bonding glue between the bottom surface of the vortex generator and the blade surface, and improves the bonding stability.

[0079] Figure 13A vortex generator with an arc-shaped bottom surface and grooves is shown. This vortex generator combines the advantages of the arc-shaped surface and the grooves 101. While increasing the contact area between the base 10 and the blade, it can make the contact surface closer to the blade surface, which is beneficial to the uniform distribution of the adhesive between the bottom surface of the vortex generator and the blade surface, and improves the bonding stability.

[0080] An embodiment of the present invention also provides a blade, which includes: a blade body and the vortex generator as described above, and the base 10 of the vortex generator is installed on the blade body. The vortex generator in the embodiment of the present invention can effectively increase the vortex intensity, reduce the drag coefficient, and effectively delay the boundary layer separation on the blade surface.

[0081] In some alternative embodiments, the number of vortex generators is multiple and they are spaced apart along the axial direction of the blade body. One end of two adjacent vortex generators on the same side in the third direction converges towards each other, and the other end diverges away from each other. In this embodiment, by combining the vortex generators, the vortex intensity can be further increased, the drag coefficient can be reduced, and the boundary layer separation of the blade can be effectively delayed.

[0082] An embodiment of the present invention also provides a contour design method for the above-mentioned vortex generator, as Figure 14 shown, this contour design method includes steps S1401 to S1405.

[0083] Step S1401, determine the outer contour of the cross-section of the fin of the vortex generator;

[0084] Among them, for the shape of the outer contour of the cross-section, refer to Figure 2 . To increase the applicability, the outer contour of the cross-section is a symmetrically designed streamline curve. Compared with the vortex generator with a traditional slender rectangular cross-section fin, the leading edge of the streamline curve is arc-shaped and has a greater thickness, and the structural strength is more suitable for large-sized vortex generators. In addition, the trailing edge of the streamline shape can be modified to increase the trailing edge thickness of the fin shape.

[0085] Step S1402, perform lofting on the outer contour of the cross-section to obtain the shape of the fin;

[0086] Step S1403, design a base on the shape of the fin to obtain the initial shape of the vortex generator;

[0087] Step S1404, simulate the initial shape of the vortex generator;

[0088] Step S1405, when the simulation result meets the preset end condition, determine the initial shape as the final shape of the vortex generator.

[0089] Among them, the simulation results include the simulated value of the vortex flow rate and the simulated value of the drag coefficient. The simulated value of the vortex flow rate is used to characterize the vortex intensity of the vortex generator, and the simulated value of the drag coefficient is used to characterize the aerodynamic characteristics of the vortex generator.

[0090] The preset end condition is used to indicate that the simulated value of the vortex flow rate is greater than or equal to a preset vortex flow rate threshold and the simulated value of the drag coefficient is less than or equal to a preset drag coefficient threshold. Among them, the vortex flow rate threshold can be set according to the vortex intensity requirement of the fin. For example, the vortex flow rate threshold can be higher than the vortex flow rate generated by the vortex generator of a slender rectangular fin with the same thickness, and higher than the vortex flow rate generated by the vortex generator of an airfoil fin with a larger thickness (for example, greater than 30% of the chord length). The preset drag coefficient threshold can be less than 0.09.

[0091] In some alternative embodiments, referring to Figure 15 , when the simulation results do not meet the preset end condition, the shape design method may further include step S1406 and step S1407.

[0092] Step S1406: Modify the initial shape of the vortex generator;

[0093] Step S1407: Simulate the modified shape until the simulation results meet the preset end condition, and determine the modified shape corresponding to the simulation results as the final shape of the vortex generator.

[0094] In this embodiment, the initial shape of the vortex generator is modified by analyzing the simulation results, and through multiple rounds of iteration, the shape of the vortex generator that meets the requirements of strength and aerodynamic characteristics is finally obtained.

[0095] It should be clear that each embodiment in this specification is described in a progressive manner. For the same or similar parts between each embodiment, reference can be made to each other. The key point of each embodiment is to illustrate the differences from other embodiments. For the device embodiment, reference can be made to the description part of the method embodiment. The embodiments of the present invention are not limited to the specific steps and structures described above and shown in the figures. Those skilled in the art can make various changes, modifications, and additions after understanding the spirit of the embodiments of the present invention, or change the order between steps. And, for the sake of brevity, the detailed description of known method technologies is omitted here.

[0096] The functional blocks shown in the above-described structural block diagrams can be implemented as hardware, software, firmware, or a combination thereof. When implemented in hardware, it can be, for example, an electronic circuit, an application-specific integrated circuit (ASIC), appropriate firmware, a plug-in, a functional card, and so on. When implemented in software, the elements of the embodiments of the present invention are programs or code segments for performing the required tasks. The programs or code segments can be stored in a machine-readable medium or transmitted via a data signal carried in a carrier wave on a transmission medium or a communication link. A "machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROMs, flash memories, erasable ROMs (EROMs), floppy disks, CD-ROMs, optical discs, hard disks, fiber optic media, radio frequency (RF) links, and so on. The code segments can be downloaded via a computer network such as the Internet, an intranet, and so on.

[0097] The embodiments of the present invention can be implemented in other specific forms without departing from its spirit and essential features. For example, the algorithms described in specific embodiments can be modified without the system architecture departing from the basic spirit of the embodiments of the present invention. Therefore, the current embodiments are regarded as exemplary in all aspects rather than restrictive, the scope of the embodiments of the present invention is defined by the appended claims rather than the above description, and all changes falling within the meaning and equivalents of the claims are thus included within the scope of the embodiments of the present invention.

Claims

1. A vortex generator, It is characterized in that include: A base (10) having a top surface and a bottom surface arranged opposite to each other in a first direction; A fin (20) is arranged on the top surface and protrudes from the top surface along the first direction; in the first direction, the outer contour of the cross section of any position of the fin (20) comprises a trailing edge line (201) and a pair of streamlined curves (202); the pair of streamlined curves (202) are symmetrically distributed relative to the first axis (L1) in the second direction; each of the streamlined curves (202) comprises a first curve segment (S1) and a second curve segment (S2) arranged successively along a third direction; the pair of first curve segments (S1) converge to a leading edge point (O) at one end of the third direction away from the second curve segment (S2); the pair of second curve segments (S2) are spaced apart from each other at one end of the third direction away from the first curve segment (S1) and are respectively connected to the trailing edge line (201); The first curved segment (S1) is an arc segment, and along the third direction, the vertical distance from the second curved segment (S2) to the first axis (L1) increases first and then decreases, and the first direction, the second direction and the third direction are arranged to intersect each other.

2. The vortex generator according to claim 1, It is characterized in that The vertical distance from the leading edge point (O) to the trailing edge line (201) along the third direction is H, and the span of the first curved segment (S1) in the third direction is h1, wherein h1≤5%H.

3. The vortex generator according to claim 1, It is characterized in that The vertical distance from the leading edge point (O) to the trailing edge line (201) along the third direction is H, and the distance from the projection point on the first axis (L1) along the second direction from the point with the largest vertical distance from the second curved segment (S2) to the first axis (L1) to the leading edge point (O) is h2, wherein 40%H≤h2≤60%H.

4. The vortex generator according to claim 1, It is characterized in that The vertical distance from the leading edge point (O) to the trailing edge line (201) along the third direction is H, and the vertical distance between the two end points of the trailing edge line (201) in the second direction is h3, wherein 3%H≤h3≤30%H.

5. The vortex generator according to claim 1, It is characterized in that The base (10) is provided with two or more positioning holes (102) on both sides of the second direction, respectively; the two or more positioning holes (102) on the same side are spaced apart in the third direction; and in the second direction, each positioning hole (102) on one side of the base (10) and one of the positioning holes (102) on the other side are symmetrically distributed relative to the center of the base (10).

6. The vortex generator according to claim 5, It is characterized in that Each positioning hole (102) is provided with a mark, and the marks of every two positioning holes (102) that are centrally symmetrically distributed are the same.

7. The vortex generator according to claim 5, characterized in that, the included angle between the connection line of two positioning holes (102) symmetrically distributed at the center of the base (10) and the third direction is θ, where 3° ≤ θ ≤ 40°.

8. The vortex generator according to claim 1, characterized in that, a groove (101) is provided on the base (10), and the groove (101) is recessed from the bottom surface along the first direction toward the side where the top surface is located.

9. The vortex generator according to claim 1, characterized in that, the bottom surface is an arc surface, and the arc surface is concave toward the top surface along the first direction.

10. The vortex generator according to claim 1, characterized in that, the connection point of the first curve segment (S1) and the second curve segment (S2) on the same side along the third direction is continuous based on the first-order partial derivative.

11. The vortex generator according to claim 1, characterized in that, the end of the second curve segment (S2) and the trailing edge line (201) on the same side along the third direction are connected by an arc transition.

12. The vortex generator according to claim 1, characterized in that, the second curve segment (S2) is generated by a polynomial function.

13. A blade, characterized in that, comprising: a blade body; the vortex generator according to any one of claims 1 to 12, and the base (10) of the vortex generator is installed on the blade body.

14. The blade according to claim 13, characterized in that, the number of the vortex generators is multiple and they are distributed at intervals along the axial direction of the blade body, and one ends of two adjacent vortex generators on the same side along the third direction converge toward each other, and the other ends diverge away from each other.

15. A contour design method for the vortex generator according to any one of claims 1 to 12, characterized in that, the contour design method includes: determining the outer contour of the cross-section of the fin of the vortex generator; performing lofting on the outer contour of the cross-section to obtain the contour of the fin; designing a base on the contour of the fin to obtain the initial contour of the vortex generator; simulating the initial contour of the vortex generator; when the simulation result meets the preset end condition, determining the initial contour as the final contour of the vortex generator.

16. The contour design method according to claim 15, characterized in that, when the simulation result does not meet the preset end condition, the contour design method further includes: correcting the initial contour of the vortex generator; simulating the corrected contour until the simulation result meets the preset end condition; determining the corrected contour corresponding to the simulation result as the final contour of the vortex generator.

17. The design method according to claim 15, characterized in that, the simulation result includes a simulated vortex flow value and a simulated drag coefficient value, and the preset end condition is used to indicate that the simulated vortex flow value is greater than or equal to a preset vortex flow threshold and the simulated drag coefficient value is less than or equal to a preset drag coefficient threshold.

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