CN113705118A - Method for calculating wake turbulence intensity of wind turbine - Google Patents
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Abstract
The invention discloses a method for calculating the turbulence intensity of wake flow of a wind turbine, which comprises the following steps: calculating the distribution type of the intensity of the turbulence in the flowing direction in the vertical direction, the radius of the wake flow at any flowing direction section position of the wake flow region and the maximum additional turbulence intensity generated by the wake flow effect based on the inflow wind resource information, the characteristic parameters of the wind turbine generator and other basic data; and calculating the additional turbulence intensity and the 'suppression' turbulence intensity at the wake zone position; and calculating the flow direction turbulence intensity of any position of the wake flow of the wind turbine based on the steps. The method can predict the flow direction turbulence intensity of any space position with high precision, particularly the double-peak distribution of the near wake turbulence intensity and the turbulence weakening effect of the near ground position, and the prediction precision is superior to the numerical simulation result based on computational fluid mechanics. An accurate and efficient turbulence calculation tool is provided for wind turbine design and wind power plant unit layout optimization in wind engineering projects.
Description
Technical Field
The invention belongs to the technical field of new energy wind power generation, and particularly relates to an accurate and rapid calculation method for the wake turbulence intensity of a wind turbine, which can be used for wind engineering projects such as wind turbine design and wind farm micro site selection.
Background
The wind flows through the wind turbine to form wake flow at the downstream of the wind turbine, then expands and meanders in the longitudinal direction and the vertical direction, and finally dissipates in a nearly chaotic mode. The wind turbine wake flow structure is complex, and the wind turbine wake flow structure comprises a blade tip vortex, a blade root vortex, a hub vortex and other multi-scale coupled vortex systems, so that the airflow disturbance in a wake area is severe, and the turbulence intensity is increased. The turbulence intensity is an important factor influencing the fatigue load and the limit load of the wind turbine generator and becomes one of important parameters of IEC61400-1 wind turbine safety grade classification. Therefore, the development of the research on the turbulence intensity of the wake flow of the wind turbine has important guiding significance for the work of wind resource assessment, wind turbine design and model selection, micro site selection of a wind power plant and the like in wind engineering projects.
In the wind power plant, the effective turbulence intensity born by each unit consists of inflow environment turbulence and wake turbulence. The environment turbulence refers to inflow turbulence which is not interfered by other units or obstacles and is determined by the geomorphic conditions of the wind power plant; the wake turbulence refers to additional turbulence introduced by wake generated by surrounding units and is determined by the factors such as the unit running state, the unit layout, the installation spacing and the like. At present, a wake effect quantitative characterization method based on an engineering model is generally accepted and applied in wind engineering projects and is an urgent need of wind power enterprises. In wind engineering research, the turbulence intensity of the flow direction parallel to the average wind speed direction is mainly considered. For this purpose, a series of engineering prediction models are proposed in succession, mainly from one-dimensional to two-dimensional to three-dimensional, from the consideration of single influencing factors to comprehensive multifactorial factors (including surface roughness, inflow turbulence intensity, atmospheric stability, wind turbine aerodynamics, etc.), such as Frandsen, Larsen, Quarton, Gao, Takeshi and Ge models (Kaldelli J K, triantaphyllou P, Stiniis P. Critical evaluation of wind turbines' analytical devices models [ J ]. Renewable and stationary Energy Reviews,2021,144 (110991); Gao X, Li B, Wang T, et al investment and evaluation of 3D wave for a horizontal-axis wind turbine structures [ J ]. 2020,260).
The model solves the problem of predicting the turbulence intensity of the wake flow direction of the wind turbine to a certain extent. However, the existing engineering models still have the following problems: (1) most models are limited to predicting the maximum turbulence intensity of the wake area of the wind turbine, and the turbulence intensity of the wake area is considered to be changed only along with the flow direction distance x and is constant in the transverse wind direction and the vertical direction, namely, the model is a one-dimensional model. This is clearly not in accordance with the actual situation. (2) The two-dimensional model can reflect the flow direction of a hub height plane and the cross wind direction turbulence intensity distribution condition, in the calculation process, the calculation of the wake flow radius is involved, and most of the relevant models adopt the wake flow radius model of the classic Jensen model. However, the Jensen wake flow radius model assumes that the wind turbine wake flow is linearly expanded at the downstream and is wirelessly expanded at infinity, which is seriously inconsistent with the actual situation; (3) for a few three-dimensional models proposed recently (Ishihara T, Qian G W.A new Gaussian-based analytical wave model for Wind turbines with requirements of turbulence intensity and Wind coeffective effects [ J ]. Journal of Wind Engineering and Industrial atmospheric dynamics,2018,177: 275-292.; Chinese patent CN112347611A,2021, Gominding et al), it is assumed that turbulence intensity is Gaussian distributed in the transverse Wind direction and the vertical direction, the formula form is complex and the calculation process is cumbersome. In addition, the calculation of some variables such as the wake radius only considers the influence of a single factor, but does not comprehensively consider the influence of multiple factors, which influences the application universality of the model in multiple types of working conditions.
In summary, on one hand, most of the turbulence intensity calculation models proposed in the current published work have low dimensionality and are not enough to fully reflect wake field information; on the other hand, most computational models consider only the effect of a single or two parameters on the wake field, and ignore the combined effect of other factors.
Disclosure of Invention
The purpose of the invention is as follows: the invention aims to provide a wind turbine wake turbulence intensity calculation method which considers the multi-parameter coupling effect, is accurate, efficient and strong in universality.
The technical scheme is as follows: the invention discloses a method for accurately and rapidly calculating the wake turbulence intensity of a wind turbine, which comprises the following steps of:
(1) acquiring inflow wind resource information and wind generating set characteristic parameters;
(2) calculating initial flow direction turbulence intensity distribution profile I of inflow0(z)；
(3) Calculating the radius r of the wake flow at any section position of the wake flow areaxDetermining a wake flow influence range;
(4) calculating the maximum additional turbulence intensity I generated by the wake effect at any section position of the wake flow area of the wind turbineadd,max(x)；
(5) Calculating the additional turbulence intensity I at the location of the wake (x, y, z) based on a bimodal distribution functionadd(x,y,z)；
(6) Calculating the 'inhibition' turbulence intensity delta I (x, y, z) of the wake flow (x, y, z) position of the wind turbine, and correcting the asymmetry of the additional turbulence intensity in the vertical direction;
(7) inflow-based flow direction turbulence intensity I0(z) additional turbulence intensity Iadd(x, y, z) and 'suppressing' turbulence intensity delta I (x, y, z), calculating the flow direction turbulence intensity I of any (x, y, z) position of the wake flow of the wind turbinewake(x,y,z)。
In the step (1), the basic data to be acquired includes: local landform grade of wind turbine planned installation position and inflow wind speed u of wind turbine hub height position0,hubAnd intensity of turbulence I0,hubVertical distribution of turbulence intensity of incoming turbulent wind (obtained by multipoint anemometry equipment), diameter D of wind wheel of wind turbine and height z of hubhubThrust coefficient curve Ct(u0,hub) And the like.
In the step (2), inflow initial turbulence intensity I0(z) the formula is:
in the formula (I), the compound is shown in the specification,z is the height from the ground, zhubIs the hub height, I0,hubThe turbulence intensity at the hub height of the wind turbine is shown, and alpha is an index of a wind speed profile. I is0,hubMeasured by wind speed measuring equipment; the wind shear index alpha is related to local landform, and the value range of alpha is 0.1-0.27 (the values of alpha corresponding to the four classes of grades are 0.1, 0.15, 0.20 and 0.27 respectively) according to the ground surface roughness grade (totally divided into four classes of grades).
In the step (3), the radius r of the wake flowxThe calculation formula of (2) is as follows:
in the formula, rdThe radius of the wind wheel is shown, and x is the flow direction distance between any position at the downstream of the wind turbine and the position of the wind wheel.
In step (4), the maximum additional turbulence intensity Iadd,max(x) The calculation formula of (2) is as follows:
in step (5), adding turbulence intensity IaddThe formula for the calculation of (x, y, z) is:
in the formula, rdIs the radius of the wind wheel, rxIs the wake radius (the calculation formula is shown in step 3), and r is the center point (x, y) of any space position (x, y, z) and the x section of the space positionhub,zhub) The distance of (a) to (b),
y and z are respectively the coordinates of the transverse wind direction and the vertical direction.
In step (6), the calculation formula of the "suppression" turbulence intensity Δ I (x, y, z) is as follows:
in step (7), the intensity of turbulence in the flow direction IwakeThe formula for the calculation of (x, y, z) is:
has the advantages that: compared with the prior art, the invention has the following remarkable advantages: (1) the method has three-dimensional properties, and can comprehensively predict the turbulence intensity distribution condition of the wake flow of the wind turbine in a three-dimensional space (flow direction, transverse wind direction and vertical direction); (2) the method has coupling attributes of multiple parameters (such as local landform, inflow turbulence intensity, wind turbine geometric characteristics and operation state), and can evaluate the influence of each factor on the wake effect of the wind turbine in a more detailed manner; (3) the characteristic and the specificity of the turbulence intensity distribution of the wake flow direction of the wind turbine, such as the 'bimodal' distribution of near-wake turbulence intensity and the 'turbulence weakening' effect of a near-ground position, are effectively reflected, and the prediction precision is even better than the numerical simulation result based on Computational Fluid Dynamics (CFD). The invention can provide an accurate and efficient turbulence calculation tool for wind turbine design and wind power plant unit layout optimization in wind engineering projects.
Drawings
FIG. 1 is a flow chart of the present invention;
FIG. 2 is a schematic diagram of a wind turbine wake flow direction turbulence intensity calculated in a three-dimensional space according to the present invention in a multi-level manner;
FIG. 3 is a graph of the predicted turbulence intensity of the wake flow direction of the Sexbierum wind turbine in embodiment 1, including the distribution curves of the turbulence intensity along the crosswind direction y at different downstream positions (x ═ 2.5D, 5.5D and 8.0D) on the hub height horizontal plane;
FIG. 4; is a cloud chart of the turbulence intensity distribution of the Sexbierum wind turbine wake flow of the embodiment 1 in the height plane of a hub, the vertical height plane (the center of a wind wheel) and the vertical plane at the downstream 5.5D position;
fig. 5 is a distribution curve of turbulence intensity of the vertical plane (passing through the center point of the wind wheel) of the WiRE EP-6030 wind turbine of the embodiment 2 at different downstream positions (x ═ 3D, 5D, 7D, 10D, 14D and 20D) along the vertical direction;
FIG. 6 is a cloud chart of the flow direction turbulence intensity distribution of the wake flow of the WiRE EP-6030 wind turbine of the embodiment 2 in the hub height plane and the vertical height plane (the center of the wind wheel);
FIG. 7 is a graph of the predicted turbulence intensity of the wake flow direction of the NREL 5MW wind turbine of embodiment 3, which includes the distribution curves of the turbulence intensity along the crosswind direction y at different positions (x is 2.5D, 5.0D and 7.5D) downstream of the hub height horizontal plane;
FIG. 8 is a cloud diagram of the flow direction turbulence intensity distribution of the wake flow of the NREL 5MW wind turbine in the three-dimensional space according to the embodiment 3.
Detailed Description
The technical scheme of the invention is further explained by combining the attached drawings.
As shown in FIG. 1, the invention provides a method for accurately and rapidly calculating the wake turbulence intensity of a wind turbine, which comprises the following steps:
(1) acquiring inflow wind resource information and wind generating set characteristic parameters;
(2) calculating initial flow direction turbulence intensity distribution profile I of inflow0(z)；
(3) Calculating the radius r of the wake flow at any section position of the wake flow areaxDetermining a wake flow influence range;
(4) calculating the maximum additional turbulence intensity I generated by the wake effect at any section position of the wake flow area of the wind turbineadd,max(x)；
(5) Calculating the additional turbulence intensity I at the location of the wake (x, y, z) based on a bimodal distribution functionadd(x,y,z)；
(6) Calculating the 'inhibition' turbulence intensity delta I (x, y, z) of the wake flow (x, y, z) position of the wind turbine, and correcting the asymmetry of the additional turbulence intensity in the vertical direction;
(7) inflow-based flow direction turbulence intensity I0(z) additional turbulence intensity Iadd(x, y, z) and 'suppressing' turbulence intensity delta I (x, y, z), calculating the flow direction turbulence intensity I of any (x, y, z) position of the wake flow of the wind turbinewake(x,y,z)。
Example 1
The Sexbierum wind power plant contains 18 rated powers of 310kW, the diameter D of a wind wheel is 30m, and the height z of a hubhubThe 35m unit is provided with a plurality of anemometers for measuring the wake field and the power generation condition of a single unit or a plurality of units. For a single wind turbine wake test, three typical positions (including three types of near wake, transition wake and far wake) of 2.5D, 5.5D and 8.0D at the downstream of the unit are main measurement objects. Selecting the wind speed U at the height position of an incoming flow hub0,hub8.4m/s, turbulence intensity I0,hubThe test condition is 10% (at this time, the corresponding wind profile exponential power alpha is 0.15, and the surface roughness z is0The thrust coefficient Ct of the wind turbine is 0.75) and the turbulence intensity distribution of the wake area of the wind turbine is predicted, and the specific steps are as follows:
(1) and confirming the inflow wind resource information, the characteristic parameters of the wind turbine generator and other basic data. Including inflow wind speed U0,hub8.4m/s, turbulence intensity I0,hub10%, and parameters such as wind profile exponent power alpha 0.15, surface roughness z00.1 m; the wind wheel diameter D of the wind turbine is 30, and the hub height zhub35m, wind turbine thrust coefficient Ct＝0.75。
(2) Setting discrete computation domains to [ -2D,25D]×[-3D,3D]×[0,6D](the flow direction x, the cross wind direction y and the vertical direction z are respectively) and D is the diameter of the wind wheel, space grids are divided, and flow field variable calculation is carried out on the space grids subsequently. According to the exponential distribution law, calculating the distribution type I of the inflow in the direction perpendicular to the turbulence intensity0(z)：
Will U0,hub＝8.4m/s，I0,hubAnd substituting the 10 percent and the alpha 0.15 into the formula to obtain the condition of the inflow wind resource.
(3) Calculating the radius r of the wakexThe formula is as follows:
will r isd＝15m，D＝30m，I0,hub＝10％，CtAnd substituting 0.75 into the formula to obtain the wake flow radius at the position x downstream of the wind turbine, namely determining the influence range of the wake flow.
(4) Calculating the maximum additional turbulence intensity Iadd,max(x) The formula is as follows:
c is to betAnd (4) substituting the value D of 0.75 into the formula to obtain the maximum additional turbulence intensity (new turbulence intensity generated by wake effect) at the position x downstream of the wind turbine.
(5) Calculating additional turbulence intensity Iadd(x, y, z), formula:
wherein r is the center point (x, y) of the x section and any position (x, y, z) in spacehub,zhub) The distance of (a) to (b),
y and z are respectively the coordinates of the transverse wind direction and the vertical direction. The I obtained by the calculation in the step (4)add,max(x) R calculated in step (3)x，rdSubstituting 15m into the above formula to obtain additional turbulence intensity Iadd(x,y,z)。
(6) Considering the phenomenon that turbulence is "inhibited" by speed shearing at the position close to the wall surface of a wake field of a wind turbine (namely the region below the height of a hub), the asymmetry of the additional turbulence intensity needs to be corrected in the vertical direction, so that the "inhibiting" turbulence intensity delta I (x, y, z) is calculated according to the formula:
the additional turbulence intensity I calculated in the step (5) isadd(x, y, z), hub height zhubSubstituting 35m into the above equation yields "suppressed" turbulence intensity Δ I (x, y, z).
(7) Calculating wake turbulence intensity Iwake(x, y, z), formula:
calculating the initial environment turbulence intensity I obtained in the step (2)0(z) the additional turbulence intensity I calculated in step (5)addSubstituting the (x, y, z) and the 'inhibition' turbulence intensity delta I (x, y, z) obtained by calculation in the step (6) into the formula to obtain the flow direction turbulence intensity I at any position (x, y, z) of the wake flow of the wind turbinewake(x,y,z)。
Through the calculation, distribution graphs of flow direction turbulence intensity of three typical positions (2.5D, 5.5D and 8.0D) at the downstream of the wind turbine along the transverse wind direction y on the height plane of the wind turbine are obtained, as shown in FIG. 3, and the distribution graphs also comprise the measurement results of an external field experiment and are based on an AL/LES method (2.5D, 5.5D and 8.0D)
T.；Laan,P.V.D.；
P. -E.; diaz, a.p.; larsen, g.c.; ott, S.Wind turbine wave models depleted at the technical unit of denomark, A review, Renew, Sustain, energy Rev, 2016,60, 752- "769) to verify the accuracy of the calculation method. From the analysis of FIG. 3, it can be seen that: in a near wake region (x is 2.5D), the 3D-MPTI model provided by the invention better embodies a 'double-peak' effect, and the position of a peak value is well matched with an experiment. As the convection of the wake and the free stream spreads, the shear mixing layer continues to expand and the "bimodal" effect of turbulence intensity gradually decays as shown by the turbulence intensity distribution at two locations, the transition wake (x ═ 5.0D) and the far wake (x ═ 8.0D). Furthermore, the invention is based on the fact that the intensity distribution (shape and size) of the turbulence is such thatThe result is closer to the experimental data and even better than the AL/LES numerical simulation result, and the excellent prediction performance is shown. FIG. 4 shows a cloud chart of turbulence intensity distribution of the wake flow of the Sexbierum wind turbine in the hub height plane and the vertical height plane (wind wheel center), and shows the three-dimensional prediction property of the method.
Example 2
In 2009, wind tunnel experiments on the wake of a wind turbine were carried out by Chamorro et al (Chanorro, L.P.; Port, age-Agel, F.A wind-turbine excitation of wind-turbine roads, Boundary-layer turbine efficiencies, Bound, Layer Meteorol.2009,132, 129-149). The experimental object is a WiRE EP-6030 wind turbine, the diameter D of a wind wheel is 0.15m, and the height z of a hub ishubThe flow variable distribution at downstream (x/D3, 5,7,10,14,20) equal cross-section positions was observed mainly at 0.125 m. The incoming flow condition is the wind speed U at the height position of the hub0,hub2.2m/s, turbulence intensity I0,hub7.0% (in this case, the corresponding wind profile exponential power α is 0.15, and the surface roughness z0＝2.5×10-5m, the wind turbine thrust coefficient Ct is 0.56). And predicting the distribution of the turbulence intensity of the wake flow of the wind turbine under the working condition.
The calculation procedure adopted in this embodiment is the same as that of embodiment 1, and the distribution of the turbulence intensity in the vertical direction of the vertical plane (passing through the center point of the wind wheel) at different downstream positions (x ═ 3D, 5D, 7D, 10D, 14D, and 20D) is calculated as shown in fig. 5. It can be obviously seen that the 3D-MPTI model provided by the invention has accurate prediction results in turbulence intensity and wake radius, and accurately predicts the peak turbulence intensity of the upper blade tip and the lower blade tip and the turbulence inhibition phenomenon of the lower swept surface. In addition, as the downstream distance increases, the gap from the experimental results becomes smaller, and after the downstream distance of 10D, almost completely coincides with the experimental data, showing an excellent far wake prediction level. Wu et al (Wu, Y. -T.; Port re-age, F.Large-efficiency Simulation of Wind-Turbine waves: Evaluation of Turbine parameters. bound Layer Metal 2011,138) have different degrees of error from the experimental data based on the AD/LES results.
Example 3
2015, Troldberg et al (Troldberg N, J)
An improved k-e model applied to a wind turbine noise in An atmospheric turbine noise.2015, 18: 889-. The diameter D of the wind wheel is 126m, and the height z of the hub ishubThe downstream (x/D2.5, 5 and 7.5) equal cross-section is mainly focused at 90 m. Wind speed U at height position of inflow hub0,hub8.0m/s, turbulence intensity I0,hub4.0% (in this case, the corresponding wind profile exponential power α is 0.10, and the wind turbine thrust coefficient Ct is 0.79). And predicting the distribution of the turbulence intensity of the wake flow of the wind turbine under the working condition.
The calculation steps adopted in this embodiment are the same as those in embodiment 1, and the calculated distributions of the turbulence intensity at three typical positions along the y direction are shown in fig. 7, from which it is seen that the method provided by the present invention obtains numerical results quite close to the AD/LES method with huge calculation amount, and the calculation time of the two methods is several seconds and several days, respectively, which greatly reduces the calculation time and saves the calculation cost. In addition, fig. 8 shows a cloud chart of turbulence intensity distribution of a wake field of the NREL 5MW wind turbine in a three-dimensional space, which well embodies the three-dimensional properties of the method of the present invention.
Compared with Sexbierum wind turbine outfield test data, wind tunnel test data of a WiRE EP-6030 small-size wind turbine model and AD/LES high-precision large-vortex simulation results of a large wind turbine NREL 5MW, the method provided by the invention can better simulate turbulence distribution in a three-dimensional space of a wake flow area, is closer to the test results in numerical value, better conforms to a real flow field in distribution profile, and has prediction precision even better than numerical simulation results based on Computational Fluid Dynamics (CFD).
Claims (8)
1. A method for calculating the turbulence intensity of the wake flow of a wind turbine is characterized in that the x axis, the y axis and the z axis of a calculation coordinate system respectively represent the flow direction, the cross wind direction and the vertical direction, and the method comprises the following steps:
(1) acquiring inflow wind resource information and wind generating set characteristic parameters;
(2) calculating initial flow direction turbulence intensity distribution profile I of inflow0(z)；
(3) Calculating the radius r of the wake flow at any section position of the wake flow areaxDetermining a wake flow influence range;
(4) calculating the maximum additional turbulence intensity I generated by the wake effect at any section position of the wake flow area of the wind turbineadd,max(x)；
(5) Calculating the additional turbulence intensity I at the location of the wake (x, y, z) based on a bimodal distribution functionadd(x,y,z)；
(6) Calculating the inhibition turbulence intensity delta I (x, y, z) of the wake flow (x, y, z) position of the wind turbine, and correcting the asymmetry of the additional turbulence intensity in the vertical direction;
(7) inflow-based flow direction turbulence intensity I0(z) additional turbulence intensity Iadd(x, y, z) and the suppression turbulence intensity delta I (x, y, z), and calculating the flow direction turbulence intensity I of any (x, y, z) position of the wake flow of the wind turbinewake(x,y,z)。
2. The method for calculating the turbulence intensity of the wake of the wind turbine as claimed in claim 1, wherein in the step (1), the inflow wind resource information includes: local landform grade of wind turbine planned installation position and inflow wind speed u of wind turbine hub height position0,hubAnd intensity of turbulence I0,hubVertical distribution of turbulence intensity of incoming turbulent wind; the characteristic parameters of the wind turbine generator set comprise the diameter D of a wind wheel of the wind turbine and the height z of a hubhubThrust coefficient curve Ct(u0,hub)。
3. The method for calculating the turbulence intensity of the wake flow of the wind turbine as claimed in claim 2, wherein in the step (2), the calculation formula of the turbulence intensity of the inflow direction of the inflow is as follows:
wherein z is the height from the ground, zhubIs the hub height, I0,hubThe turbulence intensity at the hub height of the wind turbine is shown, and alpha is an index of a wind speed profile; i is0,hubMeasured by wind speed measuring equipment; the wind shear index alpha is related to local landform, the ground surface roughness levels are divided into four classes according to the ground surface roughness levels, and the values of alpha corresponding to the four classes of levels are 0.1, 0.15, 0.20 and 0.27 respectively.
4. The method for calculating the turbulence intensity of the wake flow of the wind turbine as claimed in claim 3, wherein in the step (3), the radius r of the wake flow isxThe calculation formula of (2) is as follows:
in the formula, rdIs the radius of the wind wheel, CtThe x is the flow direction distance between any position at the downstream of the wind turbine and the position of the wind wheel.
5. The method for calculating the wake turbulence intensity of the wind turbine as claimed in claim 4, wherein in the step (4), the maximum additional turbulence intensity Iadd,max(x) The calculation formula of (2) is as follows:
6. the method for accurately and rapidly calculating the wake turbulence intensity of the wind turbine as claimed in claim 4, wherein in the step (5), the additional turbulence intensity IaddThe formula for the calculation of (x, y, z) is:
in the formula, rdIs the radius of the wind wheel, rxR is the central point (x, y) of any position (x, y, z) in space and the x section of the positionhub,zhub) The distance of (a) to (b),
y and z are respectively the coordinates of the transverse wind direction and the vertical direction.
7. The method for calculating the wake turbulence intensity of the wind turbine as claimed in claim 6, wherein in the step (6), the calculation formula of the suppression turbulence intensity Δ I (x, y, z) is as follows:
8. the method for calculating the wake turbulence intensity of the wind turbine as claimed in claim 7, wherein in the step (7), the flow direction turbulence intensity IwakeThe formula for the calculation of (x, y, z) is:
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| CN117272869A (en) * | 2023-11-15 | 2023-12-22 | 南京航空航天大学 | Full wake analysis method considering characteristics of near wake and far wake of wind turbine |
| CN117272869B (en) * | 2023-11-15 | 2024-02-09 | 南京航空航天大学 | Full wake analysis method considering characteristics of near wake and far wake of wind turbine |
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