A method and apparatus for modeling a flow field in a wake region of a wind turbine

Abstract

The application discloses a kind of wind turbine wake area flow field modeling method and device, method includes: according to the basic parameters required by flow field modeling and linear expansion assumption of wake, determine the radius of wind turbine wake area;Based on the actual evolution law of wake, determine the generation position of maximum speed loss of wake area;Based on the radius of wind turbine wake area, the generation position of maximum speed loss of wake area and the wake influence of wind turbine blade, the wind turbine wake area is divided into regions;The flow field of wind turbine wake area after dividing region is modeled, and the flow field model to be solved of wind turbine wake area is established;The flow field model to be solved of wind turbine wake area is solved, and the flow field model is obtained.Through the flow field modeling method and device provided by the application, the actual generation and evolution law of wind turbine wake is considered, the flow field of wind turbine wake area is accurately modeled, and the wake calculation precision is improved.

Description

Technical Field

[0001] This invention relates to the field of wind power generation technology, and more specifically to a method and apparatus for modeling the flow field in the wake region of a wind turbine. Background Technology

[0002] In the field of wind power generation, the wake effect of wind turbines is a significant factor affecting the power generation of wind farms. When free flow passes over a wind turbine, the turbine absorbs some energy for power generation, causing a decrease in wind speed in a certain area downstream of the turbine. This results in reduced power generation from downstream wind turbines located within the wake region. Therefore, accurate modeling of the flow field in the wake region of wind turbines can effectively improve the power generation efficiency of wind farms and reduce investment risks.

[0003] Analytical models are the primary method for modeling the flow field in the wake region of wind turbines. Existing analytical models include the Jensen model, the Frandsen model, and the Gaussian model, among which the two-dimensional analytical wake model, such as the Gaussian model, is considered to more accurately describe the flow field distribution in the wake region. One of the assumptions underlying these two-dimensional analytical wake models is that the velocity deficit in the wake region is greatest at the hub center and gradually decreases outwards from the hub center, effectively treating the entire wind turbine as a whole when modeling the wake. However, the energy absorption location of a wind turbine is on its blades, and each blade generates an individual wake effect. The wakes generated by these individual blades gradually superimpose as the flow develops, eventually forming a unified whole. Therefore, the location of the maximum velocity deficit in the wake region is not initially at the hub center, but rather at a certain location on each blade, gradually transitioning to the hub center as the wake develops. Existing two-dimensional analytical wake models do not consider the actual evolution of these wakes, which to some extent limits the accuracy of wake region flow field modeling. Summary of the Invention

[0004] Therefore, this invention provides a method and apparatus for modeling the flow field in the wake region of a wind turbine. By considering the actual generation and evolution of the wind turbine wake, a new analytical wake model is proposed to accurately model the flow field in the wake region of the wind turbine, thereby improving the accuracy of wake calculation and solving the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] In a first aspect, embodiments of the present invention provide a method for modeling the flow field in the wake region of a wind turbine, comprising:

[0007] Based on the basic parameters required for flow field modeling and the assumption of linear wake expansion, the radius of the wind turbine wake region is determined.

[0008] Based on the actual evolution of the wake, the location where the maximum velocity deficit in the wake region occurs is determined;

[0009] Based on the radius of the wind turbine wake region, the location of the maximum velocity loss in the wake region, and the wake effect of the wind turbine blades, the wind turbine wake region is divided into regions.

[0010] The flow field in the wake region of the wind turbine is modeled in separate regions to establish a flow field model to be solved in the wake region of the wind turbine.

[0011] The flow field model to be solved in the wake region of the wind turbine is obtained by solving the flow field model.

[0012] Preferably, the process of determining the radius of the wind turbine wake region includes:

[0013] Determine the basic parameters required for flow field modeling, including: wind turbine rotor diameter D0, thrust coefficient C. T and wake diffusion coefficient k w ;

[0014] Based on the basic parameters required for flow field modeling and the assumption of linear wake expansion, the radius r of the wind turbine wake region is... w for:

[0015]

[0016] Where x is the directional distance between the wake region and the wind turbine rotor surface.

[0017] Preferably, the process of determining the location of the maximum velocity deficit in the wake region based on the actual evolution law of the wake is as follows:

[0018] Based on the actual evolution of the wake, where the maximum velocity loss in the wake region occurs at a certain location on the wind turbine blade, the location where the maximum velocity loss in the wake region occurs is:

[0019] r m =α r r0

[0020] Where, r m The distance from the center of the hub to the location where the maximum velocity deficit occurs in the wake region, r0 is the radius of the wind turbine rotor, r0 = D0 / 2, a r This is the proportionality coefficient.

[0021] Preferably, the process of dividing the wake region of the wind turbine includes:

[0022] The wake effect exists in a two-dimensional plane with wind turbine blades number one and number two. Based on the fact that each blade generates a separate wake and that the wakes generated by different blades interact with each other, and combined with the radius of the wind turbine wake region and the location where the maximum velocity loss in the wake region occurs, the wind turbine wake region is divided into three regions: region 1, region 2 and region 3.

[0023] Region 1 is only affected by the wake generated by the first blade of the wind turbine, and is not affected by the wake generated by the second blade. Its range is: r w -2r m <r≤r w r is the distance from the wake region to the center line of the wheel hub;

[0024] Region 2 is only affected by the wake generated by the second blade of the wind turbine, and is not affected by the wake generated by the first blade. Its range is: -r w ≤r<2r m -r w ;

[0025] Region 3 is affected by the superimposed wake generated by the first and second blades of the wind turbine, and its range is: 2r m -r w ≤r≤r w -2r m .

[0026] Preferably, the process of performing regional modeling of the flow field in the wake region of the wind turbine after dividing the region, and establishing the flow field model to be solved in the wake region of the wind turbine, includes:

[0027] Based on the fact that the period of the trigonometric function is the same as the range of the wake effect generated by the blade, the characteristics of the velocity deficit distribution at the overall wake boundary of the wind turbine, and the velocity distribution formula in the wake region, the three regions of the wake region are modeled separately, resulting in the flow field model to be solved:

[0028]

[0029] Among them, (U) ∞ -U w ) / U ∞ For the velocity deficit in the wake region, U ∞ For the free flow velocity, U w Let r be the velocity in the wake region. (1) is the flow field model to be solved in region 1, (2) is the flow field model to be solved in region 2, and (3) is the flow field model to be solved in region 3. w Let r be the radius of the wake region, r be the distance from any position in the wake region to the center line of the wheel hub, and M be the parameter to be solved.

[0030] Preferably, the velocity distribution formula in the wake region is: Among them, parameters M, K and N are undetermined parameters. The undetermined parameter K is determined by the fact that the period of the trigonometric function is the same as the range of the wake effect generated by the blade. The relationship between the undetermined parameters M and N is determined by the fact that the velocity deficit at the overall wake boundary of the wind turbine is 0.

[0031] Preferably, by means of the law of conservation of momentum Determine the unsolved parameter M in the flow field model to be solved, wherein the unsolved parameter M is... Among them, T1, T2, T3 and T4 are four intermediate parameters introduced to simplify M.

[0032] Secondly, embodiments of the present invention provide an apparatus for modeling the flow field in the wake region of a wind turbine, comprising:

[0033] The wake radius determination unit is used to determine the wake radius of the wind turbine based on the basic parameters required for flow field modeling and the assumption of linear wake expansion.

[0034] The unit for determining the location of the maximum velocity deficit in the wake region is used to determine the location of the maximum velocity deficit in the wake region based on the actual evolution law of the wake.

[0035] The region division unit is used to divide the wake region of a wind turbine based on the radius of the wake region, the location of the maximum velocity loss in the wake region, and the wake effect of the wind turbine blades.

[0036] The flow field modeling unit is used to perform regional modeling of the flow field in the wake region of the wind turbine after the region is divided, and to establish the flow field model to be solved in the wake region of the wind turbine.

[0037] The flow field solving unit is used to solve the flow field model to be solved in the wake region of the wind turbine, and obtain the flow field model.

[0038] Thirdly, embodiments of the present invention provide a computer device, including: at least one processor, and a memory communicatively connected to the at least one processor, wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to cause the at least one processor to perform a method for modeling the wake region flow field of a wind turbine according to the first aspect of the present invention.

[0039] Fourthly, embodiments of the present invention provide a computer-readable storage medium storing computer instructions for causing a computer to execute a method for modeling the flow field in the wake region of a wind turbine according to the first aspect of the present invention.

[0040] The technical solution of this invention has the following advantages:

[0041] This invention provides a method and apparatus for modeling the flow field in the wake region of a wind turbine. The method includes: determining the radius of the wind turbine wake region based on the basic parameters required for flow field modeling and the assumption of linear wake expansion; determining the location of the maximum velocity deficit in the wake region based on the actual evolution law of the wake; dividing the wind turbine wake region into regions based on the wind turbine wake region radius, the location of the maximum velocity deficit in the wake region, and the wake influence of the wind turbine blades; performing regional modeling of the flow field in the wind turbine wake region after regionalization to establish a flow field model to be solved in the wind turbine wake region; and solving the flow field model to be solved in the wind turbine wake region to obtain the flow field model. By considering the actual generation and evolution law of the wind turbine wake, the flow field in the wind turbine wake region can be accurately modeled, improving the accuracy of wake calculation. Attached Figure Description

[0042] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0043] Figure 1 A flowchart illustrating the method for modeling the flow field in the wake region of a wind turbine provided in this embodiment of the invention;

[0044] Figure 2 A schematic diagram of the wake region division provided in this embodiment of the invention;

[0045] Figure 3 A schematic diagram of the calculation results at position x / D0 = 3 provided in this embodiment of the invention;

[0046] Figure 4 This embodiment of the invention provides a schematic diagram of the calculation results at the position x / D0 = 6;

[0047] Figure 5 A diagram illustrating the composition of the device for modeling the flow field in the wake region of a wind turbine provided in this embodiment of the invention;

[0048] Figure 6 A composition diagram of a specific example of a computer device provided in an embodiment of the present invention. Detailed Implementation

[0049] To enable those skilled in the art to better understand the present invention, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them, and are not intended to limit the scope of the present invention. Furthermore, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion regarding the concepts disclosed in the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0050] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0051] Example 1

[0052] This invention provides a method for modeling the flow field in the wake region of a wind turbine, such as... Figure 1 As shown, the method includes:

[0053] Step S1: Determine the radius of the wind turbine wake region based on the basic parameters required for flow field modeling and the assumption of linear wake expansion.

[0054] In this embodiment, the process of determining the radius of the wind turbine wake region includes:

[0055] Step S11: Determine the basic parameters required for flow field modeling, including: wind turbine rotor diameter D0, thrust coefficient C. T and wake diffusion coefficient k w .

[0056] Specifically, the wind turbine rotor diameter D0 and thrust coefficient C T The wake diffusion coefficient k is determined based on the wind turbine model. w This is an empirical parameter, determined by the environment where the wind farm is located, and its value is generally 0.05-0.075. It is only used as an example and is not a limitation.

[0057] Step S12: Based on the basic parameters required for flow field modeling and the assumption of linear wake expansion, the radius r of the wind turbine wake region is determined. w for:

[0058]

[0059] Where x is the directional distance between the wake region and the wind turbine rotor surface.

[0060] Step S2: Based on the actual evolution of the wake, determine the location where the maximum velocity deficit in the wake region occurs.

[0061] In this embodiment, based on the actual evolution of the wake where the maximum velocity loss in the wake region occurs at a certain location on the wind turbine blade, the location where the maximum velocity loss in the wake region occurs is:

[0062] r m =α r r0

[0063] Where, r m The distance from the center of the hub to the location where the maximum velocity deficit occurs in the wake region, r0 is the radius of the wind turbine rotor, r0 = D0 / 2, a r This is the proportionality constant. It should be noted that the proportionality constant 'a'... r Based on experience, since wind turbines primarily absorb wind energy on the outer side of their blades, therefore a r The value range is generally 0.5 to 0.8, which is only used as an example and should be determined according to the actual application requirements.

[0064] Step S3: Based on the radius of the wind turbine wake region, the location of the maximum velocity loss in the wake region, and the wake influence of the wind turbine blades, the wind turbine wake region is divided into areas.

[0065] In this embodiment, the wake effect is typically represented by wake development in a two-dimensional plane, which contains a first blade on the upper side and a second blade on the lower side, such as... Figure 2 As shown. Based on the fact that each blade generates a separate wake and that the wakes generated by different blades interact with each other, and combined with the radius of the wind turbine's wake region and the location where the maximum velocity loss in the wake region occurs, the wind turbine's wake region is divided into three regions: Region 1, Region 2, and Region 3.

[0066] Region 1 is only affected by the wake generated by the first blade of the wind turbine, and is not affected by the wake generated by the second blade. Its range is: r w -2r m <r≤r w Where r is the distance from the wake region to the hub centerline. It should be noted that the influence area of ​​the wake generated by the second blade is 2(r). w -r m Given that the lower boundary of the wake effect generated by blade number two is -r w It can be seen that the upper boundary is r. w -2r m Therefore, the range of region 1 is r. w -2r m <r≤r w .

[0067] Region 2 is only affected by the wake generated by the second blade of the wind turbine, and is not affected by the wake generated by the first blade. Its range is: -r w ≤r<2rm -r w It should be noted that the area affected by the wake generated by the first blade is 2(r). w -r m Given that the upper boundary of the wake effect generated by blade number one is r w It can be seen that the lower boundary is 2r. m -r w Therefore, the range of region 2 is -r. w ≤r<2r m -r w .

[0068] Region 3 is affected by the superimposed wake generated by the first and second blades of the wind turbine, and its range is: 2r m -r w ≤r≤r w -2r m It should be noted that the lower boundary 2r of the wake effect generated by the first blade is... m -r w And the upper boundary of the wake effect generated by the second blade is r. w -2r m Therefore, the range of region 3 is 2r. m -r w ≤r≤r w -2r m .

[0069] Step S4: Perform regional modeling of the flow field in the wake region of the wind turbine after dividing the region, and establish the flow field model to be solved in the wake region of the wind turbine.

[0070] In this embodiment, the velocity distribution formula in the wake region is: Among them, (U) ∞ -U w ) / U ∞ For the velocity deficit in the wake region, U ∞ For the free flow velocity, U w Let r be the velocity in the wake region, and r be the distance from any position in the wake region to the hub centerline. Parameters M, K, and N are undetermined parameters. The undetermined parameter K is determined by the period of a trigonometric function being the same as the range of the wake influence area generated by the blade. The relationship between the undetermined parameters M and N is determined by the velocity deficit being 0 at the overall wake boundary of the wind turbine.

[0071] In one specific embodiment, the velocity loss of the wake generated by each blade of the wind turbine follows a trigonometric function distribution, and the maximum velocity loss of the wake generated by the first blade occurs at r. m The location determines the velocity distribution in the wake region, which satisfies the following:

[0072]

[0073] Based on the periodic characteristics of trigonometric functions and the wake distribution pattern, it can be seen that the period of the trigonometric function is the same as the influence range of the wake generated by the first blade, resulting in the following formula:

[0074]

[0075] Furthermore, because at the boundary of the overall wake of the wind turbine, i.e., r = r w At this point, the speed deficit is 0, therefore:

[0076] Mcos(K(r w -r m ))+N=0

[0077] From the above formula, we can obtain K = π / (r w -r m If M = N, then the velocity distribution of the wake generated by blade number one satisfies:

[0078]

[0079] Similarly, the maximum velocity deficit that generates the wake from the second blade occurs at -r m The location, and the velocity distribution in its wake region, satisfy:

[0080]

[0081] In summary, by modeling the three regions of the wake region separately, the flow field model to be solved is obtained as follows:

[0082]

[0083] Wherein, (1) corresponds to the flow field model to be solved in region 1, (2) corresponds to the flow field model to be solved in region 2, and (3) corresponds to the flow field model to be solved in region 3, r w Let r be the radius of the wake region, r be the distance from any position in the wake region to the center line of the wheel hub, and M be the parameter to be solved.

[0084] Step S5: Solve the flow field model to be solved in the wake region of the wind turbine to obtain the flow field model.

[0085] In this embodiment, the law of conservation of momentum is applied. The parameters M to be solved in the flow field model are determined. Specifically, based on the established flow field model and the momentum conservation theorem, the flow field in the wake region of the wind turbine is solved, and the impact of the wake on the power generation of the wind turbine in the wake region can be calculated and evaluated. The solution process is as follows:

[0086]

[0087]

[0088] Calculated T1, T2, T3, and T4 are four intermediate parameters introduced to simplify M. It should be noted that these four intermediate parameters have no meaning and are only used to simplify the result, that is, to simply characterize the parameter M to be solved. They are specifically represented as follows:

[0089]

[0090]

[0091]

[0092]

[0093] In one specific embodiment, the two flow cross sections x / D0 = 3 and x / D0 = 6 in the wake region of the wind turbine are modeled and solved. The specific process includes:

[0094] 1. Determine the basic parameters required for flow field modeling and the radii of the wake region at the two flow cross sections x / D0=3 and x / D0=6 in the wake region of the wind turbine.

[0095] In this embodiment, a model wind turbine is selected, with a rotor diameter D0 = 1.1m and a thrust coefficient C. T =0.75, wake diffusion coefficient k w =0.065. Based on the linear expansion assumption of the wake, when x / D0 = 3, we know that x = 3.3m. Therefore, the radius r of the overall wake region of the wind turbine is... w =0.888m; when x / D0 = 6, we know x = 6.6m, then the radius r of the overall wake region of the wind turbine is... w =1.103m.

[0096] 2. Determine the location where the maximum velocity deficit occurs in the wake region.

[0097] In this embodiment, r0 = D0 / 2 = 0.55m, α r Taking 0.535, then based on the location r where the maximum velocity deficit occurs in the wake region... m =α r r0 indicates that r m =0.294m.

[0098] 3. Based on the division criteria of the wind turbine wake region into three regions, determine the range of each sub-region of the two flow cross sections x / D0=3 and x / D0=6 in the wind turbine wake region.

[0099] In this embodiment, when x / D0 = 3, the radius r of the overall wake region of the wind turbine is used as the reference. w =0.888m and the location r where the maximum velocity deficit in the wake occursm From \(r = 0.294m\), it can be seen that:

[0100] Range of Region 1: \(0.3 < r\leq0.888\). This region is only affected by the wake generated by the first blade of the wind turbine and not by the wake generated by the second blade.

[0101] Range of Region 2: \(-0.888\leq r < -0.3\). This region is only affected by the wake generated by the second blade of the wind turbine and not by the wake generated by the first blade.

[0102] Range of Region 3: \(-0.3\leq r\leq0.3\). This region is affected by the superposition of the wakes generated by the first and second blades of the wind turbine.

[0103] When \(x / D_0 = 6\), according to the radius \(r\) of the overall wake region of the wind turbine w \(= 1.103m\) and the position \(r\) where the maximum velocity deficit in the wake region occurs m \(= 0.294m\), it can be seen that:

[0104] Range of Region 1: \(0.514 < r\leq1.103\). This region is only affected by the wake generated by the first blade of the wind turbine and not by the wake generated by the second blade.

[0105] Range of Region 2: \(-1.103\leq r < -0.514\). This region is only affected by the wake generated by the second blade of the wind turbine and not by the wake generated by the first blade.

[0106] Range of Region 3: \(-0.514\leq r\leq0.514\). This region is affected by the superposition of the wakes generated by the first and second blades of the wind turbine.

[0107] 4. Solve the flow field model to be solved in the wake region of the wind turbine to obtain the flow field model.

[0108] In this embodiment, when \(x / D_0 = 3\), according to the law of conservation of momentum, it can be known that:

[0109] \(T1 = -3.302\), \(T2 = -8.731\), \(T3 = 20.293\), \(T4 = 34.586\) and \(M = 0.247\);

[0110] Also, because \(r\) w \(= 0.888m\), \(r\) m \(= 0.294m\), substituting into the flow field model to be solved can obtain the flow field distribution in the wake region at \(x / D_0 = 3\), as Figure 3 shown.

[0111] When \(x / D_0 = 6\), according to the law of conservation of momentum, it can be known that:

[0112] Given T1 = -6.117, T2 = -10.393, T3 = 34.188, T4 = 63.493, we can deduce that M = 0.121.

[0113] And because r w =1.103m, r m =0.294m, substituting this into the flow field model to be solved yields the flow field distribution in the wake region at x / D0=6, as follows. Figure 4 As shown.

[0114] It should be noted that, Figure 3 and Figure 4 The paper also showcases commonly used analytical wake models (Gaussian models) and experimental results. The experimental results, obtained through actual measurements of the wind turbine flow field, are more accurate and serve as benchmark data. As can be seen from the figures, compared to the Gaussian model, the analytical wake model provided in this embodiment of the invention better matches the experimental results, verifying the model's accuracy. This demonstrates that the method for modeling the wind turbine wake region flow field proposed in this embodiment can consider the actual generation and evolution of the wind turbine wake, accurately modeling the flow field in the wind turbine wake region and improving the accuracy of wake calculations.

[0115] Example 2

[0116] This invention provides an apparatus for modeling the flow field in the wake region of a wind turbine, such as... Figure 5 As shown, it includes:

[0117] The wake radius determination unit is used to determine the wake radius of the wind turbine based on the basic parameters required for flow field modeling and the assumption of linear wake expansion. This module executes the method described in step S1 of Example 1, which will not be repeated here.

[0118] The unit for determining the location of the maximum velocity deficit in the wake region is used to determine the location of the maximum velocity deficit in the wake region based on the actual evolution law of the wake. This module executes the method described in step S2 of embodiment 1, which will not be repeated here.

[0119] The region division unit is used to divide the wake region of the wind turbine based on the radius of the wake region, the location of the maximum velocity loss in the wake region, and the wake influence of the wind turbine blades. This module executes the method described in step S3 of embodiment 1, which will not be repeated here.

[0120] The flow field modeling unit is used to perform regional modeling of the flow field in the wake region of the wind turbine after the region is divided, and to establish the flow field model to be solved in the wake region of the wind turbine. This module executes the method described in step S4 of embodiment 1, which will not be repeated here.

[0121] The flow field solving unit is used to solve the flow field model to be solved in the wake region of the wind turbine to obtain the flow field model; this module executes the method described in step S5 of embodiment 1, which will not be repeated here.

[0122] The device for modeling the flow field in the wake region of a wind turbine provided by this invention proposes a new analytical wake model to accurately model the flow field in the wake region by considering the actual generation and evolution of the wind turbine wake, thereby improving the accuracy of wake calculation.

[0123] Example 3

[0124] This invention provides a computer device, such as... Figure 6 As shown, the system includes: at least one processor 601, at least one communication interface 603, a memory 604, and at least one communication bus 602. The communication bus 602 is used to enable communication between these components. The communication interface 603 may include a display screen and a keyboard; optionally, the communication interface 603 may also include a standard wired interface or a wireless interface. The memory 604 may be a high-speed volatile random access memory, an unstable memory, or at least one storage device located remotely from the processor 601. The processor 601 can execute the method for modeling the wind turbine wake region flow field of Embodiment 1. The memory 604 stores a set of program code, and the processor 601 calls the program code stored in the memory 604 to execute the method for modeling the wind turbine wake region flow field of Embodiment 1.

[0125] The communication bus 602 can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. The communication bus 602 can be divided into an address bus, a data bus, and a control bus, etc. For ease of representation, Figure 6 The symbol is represented by only one line, but this does not mean that there is only one bus or one type of bus.

[0126] The memory 604 may include volatile memory, such as random access memory (RAM); the memory may also include non-volatile memory, such as flash memory, hard disk drive (HDD) or solid-state drive (SSD); the memory 604 may also include a combination of the above types of memory.

[0127] The processor 601 can be a central processing unit (CPU), a network processor (NP), or a combination of a CPU and an NP.

[0128] The processor 601 may further include a hardware chip. This hardware chip may be an Application-Specific Integrated Circuit (ASIC), a Programmable Logic Device (PLD), or a combination thereof. The PLD may be a Complex Programmable Logic Device (CPLD), a Field Programmable Gate Array (FPGA), a Generic Array Logic (GAL), or any combination thereof.

[0129] Optionally, the memory 604 is also used to store program instructions. The processor 601 can call the program instructions to implement the method for modeling the flow field in the wake region of a wind turbine as described in Embodiment 1 of the present invention.

[0130] This invention also provides a computer-readable storage medium storing computer-executable instructions that can execute the method for modeling the flow field in the wake region of a wind turbine according to Embodiment 1. The storage medium may be a magnetic disk, optical disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk drive (HDD), or solid-state drive (SSD), etc.; the storage medium may also include combinations of the above types of memory.

[0131] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for modeling the flow field in the wake region of a wind turbine, characterized in that, include: Based on the basic parameters required for flow field modeling and the assumption of linear wake expansion, the radius of the wind turbine wake region is determined. Based on the actual evolution of the wake, the location where the maximum velocity deficit in the wake region occurs is determined; Based on the radius of the wind turbine wake region, the location of the maximum velocity loss in the wake region, and the wake effect of the wind turbine blades, the wind turbine wake region is divided into areas. The flow field in the wake region of the wind turbine is modeled in separate regions to establish a flow field model to be solved in the wake region of the wind turbine. The flow field model to be solved in the wake region of the wind turbine is obtained by solving the flow field model. The process of dividing the wake region of the wind turbine includes: The wake effect exists in a two-dimensional plane with wind turbine blades number one and number two. Based on the fact that each blade generates a separate wake and that the wakes generated by different blades interact with each other, and combined with the radius of the wind turbine wake region and the location where the maximum velocity loss in the wake region occurs, the wind turbine wake region is divided into three regions: region 1, region 2 and region 3. Region 1 is only affected by the wake generated by the first blade of the wind turbine, and is not affected by the wake generated by the second blade. Its range is as follows: , r This is the distance from the wake region to the center line of the wheel hub. Region 2 is only affected by the wake generated by the second blade of the wind turbine, and is not affected by the wake generated by the first blade. Its range is as follows: ; Region 3 is affected by the superimposed wake generated by the No. 1 and No. 2 blades of the wind turbine, and its range is as follows: ; The process of performing regional modeling of the flow field in the wind turbine wake region after dividing it into regions, and establishing the flow field model to be solved in the wind turbine wake region, includes: Based on the fact that the period of the trigonometric function is the same as the range of the wake effect generated by the blade, the characteristics of the velocity deficit distribution at the overall wake boundary of the wind turbine, and the velocity distribution formula in the wake region, the three regions of the wake region are modeled separately, resulting in the flow field model to be solved: in, For the velocity deficit in the wake region, For the free flow velocity, Let be the velocity in the wake region. (1) is the flow field model to be solved for region 1, (2) is the flow field model to be solved for region 2, and (3) is the flow field model to be solved for region 3. The radius of the wake region, The distance from any point in the wake region to the center line of the wheel hub. r m The parameter is the distance from the center of the wheel hub where the maximum speed loss occurs in the wake region. M These are the parameters to be solved.

2. The method for modeling the flow field in the wake region of a wind turbine according to claim 1, characterized in that, The process of determining the radius of the wind turbine wake region includes: Determine the basic parameters required for flow field modeling, including: wind turbine rotor diameter. D 0. Thrust coefficient C T and wake diffusion coefficient k w ; Based on the basic parameters required for flow field modeling and the assumption of linear wake expansion, the radius of the wind turbine wake region is... r w for: in, x This represents the directional distance between the wake region and the wind turbine rotor surface.

3. The method for modeling the flow field in the wake region of a wind turbine according to claim 2, characterized in that, The process of determining the location of the maximum velocity deficit in the wake region based on the actual evolution law of the wake is as follows: Based on the actual evolution of the wake, where the maximum velocity loss in the wake region occurs at a certain location on the wind turbine blade, the location where the maximum velocity loss in the wake region occurs is: in, r m This is the distance from the center of the wheel hub where the maximum speed loss in the wake region occurs. r 0 represents the radius of the wind turbine rotor. , a r This is the proportionality coefficient.

4. The method for modeling the flow field in the wake region of a wind turbine according to claim 1, characterized in that, The formula for the velocity distribution in the wake region is: , where the parameters M , K and N The parameter to be determined, the parameter to be determined K The undetermined parameter is determined by the fact that the period of the trigonometric function is the same as the range of the area where the blade generates wake influence. M and N The relationship is determined by the fact that the velocity deficit at the overall wake boundary of the wind turbine is 0.

5. The method for modeling the flow field in the wake region of a wind turbine according to claim 1, characterized in that, By the law of conservation of momentum Determine the parameters to be solved in the flow field model. M The parameters to be solved M for ,in, T 1. T 2. T 3 and T 4. For simplification M Four intermediate parameters were introduced.

6. A device for modeling the flow field in the wake region of a wind turbine, characterized in that, include: The wake radius determination unit is used to determine the wake radius of the wind turbine based on the basic parameters required for flow field modeling and the assumption of linear wake expansion. The unit for determining the location of the maximum velocity deficit in the wake region is used to determine the location of the maximum velocity deficit in the wake region based on the actual evolution law of the wake. The region division unit is used to divide the wake region of the wind turbine based on the radius of the wake region, the location where the maximum velocity loss in the wake region occurs, and the wake influence of the wind turbine blades. The flow field modeling unit is used to perform regional modeling of the flow field in the wake region of the wind turbine after the region is divided, and to establish the flow field model to be solved in the wake region of the wind turbine. The flow field solving unit is used to solve the flow field model to be solved in the wake region of the wind turbine to obtain the flow field model; The process of dividing the wake region of the wind turbine includes: The wake effect exists in a two-dimensional plane with wind turbine blades number one and number two. Based on the fact that each blade generates a separate wake and that the wakes generated by different blades interact with each other, and combined with the radius of the wind turbine wake region and the location where the maximum velocity loss in the wake region occurs, the wind turbine wake region is divided into three regions: region 1, region 2 and region 3. Region 1 is only affected by the wake generated by the first blade of the wind turbine, and is not affected by the wake generated by the second blade. Its range is as follows: , r This is the distance from the wake region to the center line of the wheel hub. Region 2 is only affected by the wake generated by the second blade of the wind turbine, and is not affected by the wake generated by the first blade. Its range is as follows: ; Region 3 is affected by the superimposed wake generated by the No. 1 and No. 2 blades of the wind turbine, and its range is as follows: ; The process of performing regional modeling of the flow field in the wind turbine wake region after dividing it into regions, and establishing the flow field model to be solved in the wind turbine wake region, includes: Based on the fact that the period of the trigonometric function is the same as the range of the wake effect generated by the blade, the characteristics of the velocity deficit distribution at the overall wake boundary of the wind turbine, and the velocity distribution formula in the wake region, the three regions of the wake region are modeled separately, resulting in the flow field model to be solved: in, For the velocity deficit in the wake region, For the free flow velocity, Let be the velocity in the wake region. (1) is the flow field model to be solved for region 1, (2) is the flow field model to be solved for region 2, and (3) is the flow field model to be solved for region 3. The radius of the wake region, The distance from any point in the wake region to the center line of the wheel hub. r m The parameter is the distance from the center of the wheel hub where the maximum speed loss occurs in the wake region. M These are the parameters to be solved.

7. A computer device, characterized in that, include: At least one processor, and a memory communicatively connected to the at least one processor, wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to cause the at least one processor to perform the method for modeling the flow field in the wake region of a wind turbine as described in any one of claims 1-5.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing the computer to perform the method for modeling the flow field in the wake region of a wind turbine as described in any one of claims 1-5.

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