Algorithm for high-resolution wind shear of surface stratum

Abstract

The invention discloses a surface layer high-resolution wind shear algorithm, which comprises the following steps of: S1, constructing a triangulation network for ground automatic stations of a research area based on geographic positions of the ground automatic stations of the research area; s2, based on a vector variance method, calculating to obtain a wind shear value of each independent triangular region in the triangulation network; and S3, repeating the step S2 to complete the calculation of the wind shear values of the rest triangular regions, and obtaining the horizontal wind shear values of all positions of the surface layer of the research region. According to the method, a credible wind shear calculation result can be obtained at any point in the area covered by the automatic station, so that effective guidance can be provided for surface layer flight.

Description

Technical Field

[0001] The invention belongs to the technical field of intelligent weather forecasting, and in particular relates to an algorithm for high-resolution wind shear in a near-surface layer. Background Art

[0002] With the rapid development of low-altitude economy, low-altitude flight has higher and higher requirements for meteorological support conditions. The most important weather factor affecting aircraft flight safety is wind shear.

[0003] At present, wind shear is not a direct detection factor, and diagnostic calculations need to be performed based on the detected wind. The wind measurement equipment currently deployed in meteorological services mainly includes weather radars, wind profiler radars, and ground automatic stations. Among them, weather radars are in elevation scanning detection mode. In order to reduce scanning obstructions, weather radars are generally installed at higher locations, such as mountain tops. The height of some weather radars is already higher than 120 meters, so there is little radar wind measurement data available below 120 meters. Wind profiler radar is in vertical detection mode, which can measure the wind at fixed points from the ground to different heights in the sky, but its spatial resolution is very low.

[0004] In current meteorological services, only ground automatic stations are used as site detection to directly measure wind, and there is no product that uses wind measurement data from ground automatic stations to calculate wind shear. In practice, the distribution of ground automatic stations is uneven, and traditional wind shear algorithms can usually only calculate the wind shear vector between two stations. , and the wind shear at some points in space may have multiple results or the wind shear value cannot be solved, such as Figure 1 As shown in the figure, when point a is exactly on the line connecting automatic stations 1 and 2, and automatic stations 3 and 4, using the two-point method to calculate the wind shear at point a may result in two different values. When a point is not on the line connecting any two automatic stations, as shown in point b, the wind shear at point b cannot be calculated, which is disadvantageous for the application of wind shear. Summary of the invention

[0005] Purpose of the invention: In view of the above-mentioned existing problems and shortcomings, the purpose of the present invention is to provide an algorithm for high-resolution wind shear in the near-ground layer, so as to achieve reliable wind shear calculation results at any point in the area covered by the automatic station, thereby providing effective guidance for near-ground flight.

[0006] Technical solution: To achieve the above-mentioned invention object, the present invention adopts the following technical solution: an algorithm for high-resolution wind shear in the near-surface layer, comprising the following steps: S1, based on the geographical location of the ground automatic stations in the study area, a triangulated network is constructed for the ground automatic stations in the study area; S2, based on the vector variance method, calculate the wind shear value of each independent triangle area in the triangulated network; S3, repeat step S2 to complete the calculation of the wind shear values ​​of the remaining triangular areas, and obtain the horizontal wind shear values ​​at various locations near the ground layer in the study area.

[0007] Furthermore, step S1 constructs a triangulated network for the ground automatic station based on the geographic coordinates of the ground automatic station and completes the construction through the Delaunay algorithm.

[0008] Furthermore, the vector variance method of the wind shear value of the independent triangular area in step S2 includes the following steps: S21, calculate the average wind component in the independent triangular area by the following formula: , In the formula, represents the component of the average wind in the east-west direction, It represents the north-south component of the mean wind; , , They represent the east and west components of the wind detected by the three ground automatic stations in the triangular area, , , They represent the north and south components of the wind detected by three automatic ground stations in the triangular area; S22, the wind shear value in the triangular area is calculated by the following formula , , In the formula, represents the wind shear value within the triangular area, Represents the area of ​​a triangle in units of , Var Represents the variance of the horizontal wind speed at the three vertices of the triangle.

[0009] Beneficial effects: Compared with the prior art, the present invention has the following advantages:

[0010] (1) The present invention provides a large-scale wind shear algorithm and meteorological products suitable for low-altitude flight.

[0011] (2) The present invention directly calculates wind shear using measured data in a triangular area formed by three points on a plane. The original data does not need to be interpolated, thus avoiding the smoothing that may be caused by the two-point method.

[0012] (3) Compared with the wind shear between two points obtained by the two-point method, the wind shear within the triangular area obtained by the present invention is more in line with flight requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 A schematic diagram of calculating wind shear at different points using the two-point method of the prior art; Figure 2 This is a schematic diagram of the ground automatic station triangulation network in the study area constructed by the present invention based on the Delaunay algorithm. DETAILED DESCRIPTION

[0014] The present invention is further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, various equivalent forms of modifications to the present invention by those skilled in the art all fall within the scope defined by the claims attached to this application.

[0015] The specific process of the algorithm for high-resolution wind shear in the near-surface layer of the present invention is described in detail as follows: Step 1: First, construct a triangulated network in the study area. The present invention uses the Delaunay triangulation method to construct small triangular areas. There are many ways to complete it. In a large area where ground automatic stations are deployed, every three automatic stations form a triangular area, such as Figure 2 As shown, there is no overlapping area between any triangles.

[0016] The advantages of the present invention by constructing a triangular network are: 1) compared with the two-point method, the triangular network can include all points in the study area. 2) compared with other polygonal areas, the triangular network can achieve the highest spatial resolution.

[0017] The second step is to build a stable triangulated network. Figure 2 As shown, in each independent triangular study area, the wind shear is calculated separately, namely: First, the average wind component within each triangular study area is calculated using the following formula: , , in, represents the component of the average wind in the east-west direction, It represents the north-south component of the mean wind; , , They represent the east and west components of the wind detected by the three ground automatic stations in the triangular area, , , They represent the north and south components of the wind detected by the three automatic ground stations in the triangular area.

[0018] Then, the variance Var of the wind in the triangular study area is calculated by the following formula, , Next, calculate the wind shear within the triangle area , in, Represents the area of ​​the triangle in units of The wind shear unit calculated by this formula is also , which is consistent with the physical meaning of the traditional wind shear algorithm. represent Figure 2 Wind shear values ​​within the triangle area shown.

[0019] Step 3: Calculation of wind shear over a large study area

[0020] Continue traversing Figure 2 For each triangle shown in , perform step 2 in each triangular area to obtain the wind shear value in each small triangle in the study area.

[0021] Examples:

[0022] Taking the observation of Jiangsu ground automatic weather station at 00:00 on July 1, 2020 as an example, there are a total of 1814 valid observation records, and some of the measured data are shown in Table 1.

[0023] Table 1 Station Name latitude longitude time wind direction Wind speed Zhaozhuang, Fengxian County 34.7403 116.4489 2020 / 7 / 1 0:00 98 1.9 Fengxian Wanggou 34.17 116.4828 2020 / 7 / 1 0:00 130 1.3 Qiulou Village, Sunlou Subdistrict 34.6864 116.5353 2020 / 7 / 1 0:00 132 1.8 Shicheng Village, Dashahe Town 34.5606 116.5353 2020 / 7 / 1 0:00 95 2 Sunlou Street 34.6436 116.5483 2020 / 7 / 1 0:00 123 2 Fengxian Changdian 34.7919 116.5917 2020 / 7 / 1 0:00 146 1.7 Shunhe, Fengxian County 34.8733 116.6031 2020 / 7 / 1 0:00 131 2.1 Fengxian Shouxian 34.8475 116.6039 2020 / 7 / 1 0:00 112 2.2 Dashahe Town 34.5414 116.6244 2020 / 7 / 1 0:00 116 1.6 Fengxian Shizhai 34.7747 116.6533 2020 / 7 / 1 0:00 118 1.6 Feng County 34.6719 116.6561 2020 / 7 / 1 0:00 107 2.2 Huankou Town 34.8814 116.6564 2020 / 7 / 1 0:00 162 1.3 Fengxian Songlou 34.5883 116.6983 2020 / 7 / 1 0:00 93 1.8 Huanglou Village, Liangzhai Town 34.5797 116.7219 2020 / 7 / 1 0:00 100 1.5 Huashan Town 34.6472 116.7219 2020 / 7 / 1 0:00 92 2.4 Lulou, Pei County 34.7814 116.7325 2020 / 7 / 1 0:00 93 1.5 Liangzhai, Fengxian County 34.5086 116.7519 2020 / 7 / 1 0:00 93 2.1 Songan Village, Lulou Town 34.7181 116.7592 2020 / 7 / 1 0:00 102 1.4 Longgu, Pei County 34.9092 116.8031 2020 / 7 / 1 0:00 114 1.1 Qishan, Pei County 34.6883 116.8067 2020 / 7 / 1 0:00 107 1.4 Pei County Zhuzhai Mayuan 34.7147 116.8122 2020 / 7 / 1 0:00 82 1.1 Pei County Anguo 34.8039 116.8122 2020 / 7 / 1 0:00 309 0 Zhuzhai, Pei County 34.7586 116.8239 2020 / 7 / 1 0:00 94 2.4 Fengxian Fanlou 34.4817 116.8447 2020 / 7 / 1 0:00 88 1.8 Yangtun, Pei County 34.9353 116.8564 2020 / 7 / 1 0:00 171 0.9 Peixian Estuary 34.6031 116.8844 2020 / 7 / 1 0:00 168 1 Zhangzhai, Pei County 34.6322 116.8856 2020 / 7 / 1 0:00 86 1.4 Yuhuangmiao Village, Zhangzhai Town 34.6742 116.8897 2020 / 7 / 1 0:00 79 1.9 Pei County 34.7533 116.9058 2020 / 7 / 1 0:00 127 1.8 Tongshan Heqiao 34.4708 116.9142 2020 / 7 / 1 0:00 91 1.3 Hanyuan Street 34.7761 116.9242 2020 / 7 / 1 0:00 340 0 Jing'an, Pei County 34.4936 116.9253 2020 / 7 / 1 0:00 121 1.8 Peicheng Subdistrict 34.6997 116.9433 2020 / 7 / 1 0:00 121 1.3 Xiaoying Village, Datun Subdistrict 34.8658 116.9447 2020 / 7 / 1 0:00 93 1 Downward trip to Xuji 34.5372 116.9619 2020 / 7 / 1 0:00 128 1.9 Datun Street 34.8194 116.9678 2020 / 7 / 1 0:00 103 1.7 Huzhai, Pei County 34.68 116.9731 2020 / 7 / 1 0:00 94 1.4 Anzhuang Village, Datun Subdistrict 34.8247 116.9847 2020 / 7 / 1 0:00 121 1 Downward trip to Xuji 34.5069 116.99 2020 / 7 / 1 0:00 56 0.9 Zhangzhuang, Pei County 34.5239 117.0033 2020 / 7 / 1 0:00 48 1.5 Shilou Village, Liuji Town 34.3508 117.0114 2020 / 7 / 1 0:00 100 1.8 Tongshan Huangji 34.4558 117.0119 2020 / 7 / 1 0:00 71 0 Pei County Huxi Farm 34.7192 117.0128 2020 / 7 / 1 0:00 100 1.2 Tongshan Zhengji 34.4314 117.0417 2020 / 7 / 1 0:00 71 1.6 Beijing to Taiwan 34.3006 117.0417 2020 / 7 / 1 0:00 85 3 Wei Temple in Pei County 34.5958 117.0594 2020 / 7 / 1 0:00 103 0.8 Tongshan Liuji 34.3667 117.0697 2020 / 7 / 1 0:00 84 1 Tongshan Dapeng 34.2844 117.0714 2020 / 7 / 1 0:00 91 0 Tongshan Hanwang 34.2086 117.0761 2020 / 7 / 1 0:00 108 2.4

[0024] The triangulated network construction method of the present invention uses the principle of shortest coordinate distance and the principle of maximizing the minimum angle, i.e., the principle of uniqueness, to ensure that the line segments in the constructed regional ground automatic station triangulated network do not intersect, and the constructed triangulated network is the closest to the regularized triangulated network, which can ultimately ensure that consistent results can be guaranteed regardless of where the region is constructed, thereby ensuring the continuity of the calculation results. The present invention also ensures the stability of the region. When a ground automatic station is deleted or moved, only the wind shear of the adjacent triangles is affected. When a new automatic station is added to the region, it can ensure that other stations are not affected.

[0025] In addition, the method of the present application can be used to obtain the results of horizontal wind shear in the near-ground layer of Jiangsu. From the results, it can be seen that using the method of the present invention, any point in the research area covered by the automatic station has a reliable wind shear calculation result. Considering the actual situation, the aircraft is carried out in a plane during actual flight, except for the take-off and landing process. If the two-point method is used to calculate the wind shear, only the wind shear on the line between any two automatic stations can be obtained, and most of the areas in the flight area are not on this line. Therefore, the product obtained by the method of the present invention can effectively guide flight. Using long-term near-ground layer wind shear data, low-altitude route planning can be guided, and areas with large low-altitude wind shear can be avoided as much as possible to increase the available time of low-altitude routes. Real-time near-ground layer low-altitude wind shear products can provide route optimization for immediate low-altitude flights, and can be used to avoid strong wind shear areas in front of the flight route.

[0026] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and technical concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An algorithm for high-resolution wind shear near the surface, characterized by The following steps are involved: S1, based on the geographical location of the ground automatic stations in the study area, a triangulated network is constructed for the ground automatic stations in the study area; S2, based on the vector variance method, calculate the wind shear value of each independent triangle area in the triangulated network; S3, repeat step S2 to complete the calculation of the wind shear values ​​of the remaining triangular areas, and obtain the horizontal wind shear values ​​at various locations near the ground layer in the study area.

2. The algorithm for high-resolution wind shear near the surface layer according to claim 1 is characterized by: Step S1 constructs a triangulated network for the ground automatic station based on the geographic coordinates of the ground automatic station and completes the construction through the Delaunay algorithm.

3. The algorithm for high-resolution wind shear near the surface layer according to claim 1 is characterized by: The vector variance method of the wind shear value of the independent triangular area in step S2 comprises the following steps: S21, calculate the average wind component in the independent triangular area by the following formula: ， In the formula, represents the component of the average wind in the east-west direction, It represents the north-south component of the mean wind; , , They represent the east and west components of the wind detected by the three ground automatic stations in the triangular area, , , They represent the north and south components of the wind detected by three automatic ground stations in the triangular area; S22, the wind shear value in the triangular area is calculated by the following formula , ， In the formula, represents the wind shear value within the triangular area, Represents the area of ​​a triangle in units of , Var Represents the variance of the horizontal wind speed at the three vertices of the triangle.

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