Method, system and medium for averaging and calculating water flow resistance of branch-type rigid vegetation in slope area

Abstract

The invention relates to a method and a system for averaging and calculating water flow resistance of branch-type rigid vegetation of a slope area and a medium. The method comprises the following steps: determining a volume correction coefficient of the rigid vegetation of the slope area; the rigid vegetation area density of the slope area is determined; determining the bottom elevation of any rigid vegetation in the slope area; determining the average submerging depth of rigid vegetation in the slope area; determining the average flow velocity between rigid vegetation main stems in the slope area; determining the hydraulic radius of rigid vegetation in the slope area; and determining the slope region rigid vegetation water flow resistance coefficient. Good technical support is provided for further knowing the water flow resistance coefficients of the rigid vegetation under different submerging conditions from the level of hydraulic theory.

Description

Technical Field

[0001] The present application relates to the field of vegetation hydraulic calculation, and in particular to a method, system and medium for calculating the water flow resistance of branching rigid vegetation in a slope area by averaging. Background Art

[0002] Rich vegetation coverage can play an important role in reducing flow, blocking sand and protecting water and soil. Due to the root structure characteristics of vegetation itself, on the one hand, vegetation coverage increases water flow resistance and can reduce runoff erosion; on the other hand, plant roots hold soil and can enhance soil erosion resistance, thereby reducing soil erosion. For vegetation in slope areas, water flow resistance is not only related to the number, density, type and other parameters of the vegetation itself, but also closely related to the slope gradient and length of the slope. In the past, the parameters of water flow resistance of rigid vegetation in slope areas were often calculated by generalizing vegetation into cylindrical rod-shaped structures. On the one hand, this is because the branch structure of the plant itself is relatively complex, and on the other hand, it is difficult to quantitatively calculate the relationship between the flooded depth of vegetation and vegetation resistance. Therefore, comprehensively considering the morphological characteristics, density and number of branching rigid vegetation in slope areas, slope gradient and other parameters can improve the accuracy of previous studies for calculating the corresponding water flow resistance coefficient, and can provide important technical support for the engineering design and ecological protection of slope river sections containing branching rigid vegetation. Summary of the invention

[0003] The purpose of the embodiments of the present application is to provide a method, system and medium for averaging and calculating the water flow resistance of branching rigid vegetation in slope areas, so as to provide technical support for river ecological protection and bank slope protection.

[0004] To achieve the above objectives, this application provides the following technical solutions:

[0005] In a first aspect, an embodiment of the present application provides a method for calculating the water flow resistance of branching rigid vegetation in a slope area by averaging, comprising the following steps:

[0006] Step 1: Determine the volume correction coefficient of rigid vegetation in the slope area;

[0007] Step 2: Determine the rigid vegetation area density in the slope area;

[0008] Step 3: Determine the bottom elevation of any rigid vegetation in the slope area;

[0009] Step 4: Determine the average inundation depth of rigid vegetation in the slope area;

[0010] Step 5: Determine the average flow velocity between the main stems of rigid vegetation in the slope area;

[0011] Step 6: Determine the hydraulic radius of the rigid vegetation in the slope area;

[0012] Step 7: Determine the water flow resistance coefficient of the rigid vegetation in the slope area.

[0013] The above-mentioned correction coefficient for the volume of rigid vegetation in the slope area is as follows: for a single rigid vegetation with many branches, the actual water blocking area A a There is a certain conversion relationship between the water blocking area A of the trunk and the volume correction coefficient α of the branching rigid vegetation, then A a =αA, which represents the projection area of ​​a single rigid plant with many branches on the water surface. The volume correction coefficient α of branched rigid vegetation is expressed by the ratio of the volume of vegetation to the volume of a cylindrical rod with the same diameter under the same flooding conditions, that is, Where W is the submerged volume of rigid vegetation under a certain flooding depth; W a is the flooded volume of the cylindrical rod under the same flooding depth, W and W a All of them can be calculated through indoor experimental measurements.

[0014] The determination of the rigid vegetation area density in the slope area is specifically as follows: the rigid vegetation area density β in the slope area represents the area occupied by the rigid vegetation stems on the unit bed surface. For a rectangular uniformly distributed vegetation array, the density is given by To calculate, where S1 and S2 represent the longitudinal and transverse center distances of adjacent vegetation stems, respectively, and A d It is the horizontal cross-sectional area of ​​a single plant, measured through indoor experiments.

[0015] The method of determining the bottom elevation of any rigid vegetation in the slope area is as follows: for a uniformly distributed vegetation array, the vegetation height is defined as h m , the maximum water depth is h max , obtained through indoor experimental measurement, it is believed that the elevation at the foot of the slope is z0 = 0, and the elevation of the vegetation at the top of the slope is z n , n is the number of vegetation rows, the elevation difference between adjacent plants on the same section is Δz = S2tanθ, θ is the slope angle, for a uniformly distributed vegetation array, starting from the lowest elevation, the bottom elevation z of the i-th plant i =iS2tanθ, if z i If the vegetation at the location is flooded, then there is h max -z i =h max -iS2tanθ>0, that is, i<h max / S2tanθ, where the slope foot is obtained through indoor experimental measurement.

[0016] The specific method for determining the average submerged depth of rigid vegetation in the slope area is: i The vegetation at the site is divided into (1) elevation z according to the flooding situation i If the vegetation is not flooded, then h max -z i≤0; (2) Elevation z i If the vegetation is partially flooded, then 0≤h max -z i ≤h m ; (3) Elevation z i If the vegetation is completely flooded, then h max -z i ≥h m , define p as the number of rows of flooded vegetation, then The largest integer with p≤n, if z i If all vegetation at the location is submerged, then h max -(z i +h m )≥0, define q as the number of vegetation rows that are completely submerged, and q as the number that satisfies and q≤n is the largest positive integer. According to the above definitions of p and q, the total submerged depth of vegetation is The average inundation depth of vegetation is known

[0017]

[0018] The determination of the average flow velocity between the main stems of the rigid vegetation in the slope area is carried out by using an averaging method due to the existence of the slope. For the water body on the unit horizontal bed surface, its average depth is half of the maximum water depth, that is, For the flow area A', the flow area of ​​water on the unit bed surface is A' = Bh, which is obtained by subtracting the cross-sectional area from the effective water blocking area of ​​vegetation. a -αβ·Bh a =(1-αβ)·Bh a , where B is the width of the main groove area, h a is the flooding depth of the vegetation, measured through indoor experiments, and the average flow velocity between the main stems of rigid vegetation is Where V is the average flow velocity in the section where the rigid vegetation is located. The actual flow area of ​​the water flow is obtained through indoor experimental measurements. The average flow velocity between vegetation stems is

[0019] The specific method for determining the hydraulic radius of rigid vegetation in the slope area is as follows: for uniformly distributed rectangular plants, the average volume of fluid per unit horizontal bed surface is At this time, the unit bed surface should be the unit horizontal bed surface, not the unit bed surface on the actual slope. The vegetation water blocking area is taken as the projection area along the water flow direction. For the vegetation array on the slope, the average water blocking area of ​​the vegetation on the unit horizontal bed surface is The average hydraulic radius of the vegetation unit horizontal plane on the slope can be obtained as

[0020]

[0021] The determination of the flow resistance coefficient of the rigid vegetation in the main trough area is specifically as follows: for rigid vegetation with many branches, after introducing the volume correction coefficient α, the flow resistance of a single rigid vegetation can be expressed as In the formula, C a is the water flow resistance coefficient of the rigid vegetation in the slope area, ρ is the fluid density, and assuming that the bed surface is smooth, the following calculation relationship is obtained for the entire water body in the vegetation area based on the force balance: Where L is the length of the vegetation area, which is measured through indoor experiments. The average resistance coefficient of the prototype rigid vegetation on the slope is The calculation formula of the resistance coefficient expressed in terms of the average hydraulic radius is:

[0022] In a second aspect, an embodiment of the present application provides a system for calculating the water flow resistance of branching rigid vegetation in a slope area by averaging, comprising:

[0023] A correction coefficient determination module is used to determine the correction coefficient of the rigid vegetation volume in the slope area;

[0024] Rigid vegetation area density calculation module, used to determine the rigid vegetation area density in the slope area;

[0025] Bottom elevation calculation module, used to determine the bottom elevation of any rigid vegetation in the slope area;

[0026] Average flooding depth calculation module, used to determine the average flooding depth of rigid vegetation in slope areas;

[0027] Average flow velocity calculation module, used to determine the average flow velocity between the main stems of rigid vegetation in the slope area;

[0028] Hydraulic radius calculation module, used to determine the hydraulic radius of rigid vegetation in the slope area;

[0029] The water flow resistance coefficient calculation module is used to determine the water flow resistance coefficient of rigid vegetation in the slope area.

[0030] In a third aspect, an embodiment of the present application provides a computer-readable storage medium, which stores a program code. When the program code is executed by a processor, the steps of the method for calculating the water flow resistance of branching rigid vegetation in a slope area by averaging as described above are implemented.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] This application relies on the morphological characteristic parameters of branched rigid vegetation and the experimental environment and water flow conditions (water depth, flow rate, etc.) of the slope area. By introducing the volume correction parameters of branched rigid vegetation, the previous method of simply generalizing rigid vegetation into cylindrical rods is further optimized, and the flooded depth and vegetation resistance are averaged, that is, the average flooded depth of all vegetation is deduced, and the average resistance of all vegetation is obtained, which can improve the accuracy of the calculation of water flow resistance of branched rigid vegetation in the slope area. The calculation data is sufficient, the method mechanism is clear, the implementation process is clear, and the technical means are feasible. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 It is a flow chart of the method of the present invention.

[0035] Figure 2 This is a test model diagram of this application.

[0036] Figure 3 This is a comparison chart between the calculated and measured values ​​of the water flow resistance coefficient of branch-type rigid vegetation in the slope area. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0038] The terms "comprises," "comprising," or any other variation thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0039] The terms "first", "second", etc. are only used to distinguish one entity or operation from another entity or operation, and should not be understood as indicating or implying relative importance, nor should they be understood as requiring or implying any such actual relationship or order between these entities or operations.

[0040] like Figure 1 As shown, the present invention provides a method for calculating the water flow resistance of branching rigid vegetation in a slope area by averaging processing, which specifically includes: determining a volume correction coefficient of rigid vegetation in the slope area, determining an area density of rigid vegetation in the slope area, determining the bottom elevation of any rigid vegetation in the slope area, determining an average submerged depth of rigid vegetation in the slope area, determining an average flow velocity between main stems of rigid vegetation in the slope area, determining a hydraulic radius of rigid vegetation in the slope area, and determining a water flow resistance coefficient of rigid vegetation in the slope area.

[0041] Step 1: Determine the volume correction coefficient of rigid vegetation in the slope area;

[0042] For branched single rigid vegetation, its actual water blocking area (A a ) is often calculated by introducing the rigid vegetation volume correction coefficient α between the main trunk water blocking area (A), which is A a =αA, where α is expressed as the ratio of the volume of vegetation to the volume of a cylindrical rod with the same diameter under the same flooding conditions, which is Where W is the submerged volume of rigid vegetation under a certain flooding depth; W a is the flooded volume of the cylindrical rod under the same flooding depth, W and W a All of these can be measured through indoor experiments.

[0043] Step 2: Determine the rigid vegetation area density in the slope area;

[0044] For a rectangular uniformly distributed vegetation array, the rigid vegetation area density in the slope area can be obtained by To calculate, where S1 and S2 represent the longitudinal and transverse center distances of adjacent vegetation stems, respectively, and A d It is the horizontal cross-sectional area of ​​a single plant, which can be measured through indoor experiments.

[0045] Step 3: Determine the bottom elevation of any rigid vegetation in the slope area;

[0046] For a uniformly distributed vegetation array, the vegetation height is defined as h m , the maximum water depth is h max , can be obtained through indoor experimental measurement. It is assumed that the elevation at the foot of the slope is z0 = 0, and the elevation of the vegetation at the top of the slope is z n (n is the number of vegetation rows), the elevation difference between adjacent plants on the same section is Δz = S2tanθ (θ is the slope gradient), for a uniformly distributed vegetation array, starting from the lowest elevation, the bottom elevation z of the i-th plant i =iS2tanθ, if z i If the vegetation at the location is flooded, then there is hmax -z i =h max -iS2tanθ>0, that is, i<h max / S2tanθ, where the slope foot θ can be obtained through indoor experimental measurement.

[0047] Step 4: Determine the average inundation depth of rigid vegetation in the slope area;

[0048] For the height z i The vegetation at the site can be divided into (1) elevation z according to the flooding situation. i If the vegetation is not flooded, then h max -z i ≤0; (2) Elevation z i If the vegetation is partially flooded, then 0≤h max -z i ≤h m ; (3) Elevation z i If the vegetation is completely flooded, then h max -z i ≥h m . Define p as the number of rows of flooded vegetation, then The largest integer with p≤n, if z i If all vegetation at the location is submerged, then h max -(z i +h m )≥0. Define q as the number of all submerged vegetation rows. From step 3, we know that q satisfies and q≤n is the largest positive integer. According to the above definitions of p and q, the total submerged depth of vegetation is The average inundation depth of vegetation is known

[0049]

[0050] Step 5: Determine the average flow velocity between the main stems of rigid vegetation in the slope area

[0051] For the rigid vegetation in the slope area, due to the existence of slope, the averaging method is used for processing. For the water body on the unit horizontal bed surface, its average depth is half of the maximum water depth, that is, The flow area A' can be obtained by subtracting the cross-sectional area from the effective water-blocking area of ​​vegetation. Then the flow area of ​​water on a unit bed surface is A' = Bh a -αβ·Bh a =(1-αβ)·Bh a , where B is the width of the main groove area, h a is the flooding depth of the vegetation, which can be measured through indoor experiments. The average flow velocity between the main stems of rigid vegetation is Where V is the average flow velocity in the section where the rigid vegetation is located, which can be measured through indoor experiments. The actual flow area of ​​the water flow is The average flow velocity between vegetation stems is

[0052] Step 6: Determine the hydraulic radius of the rigid vegetation in the slope area

[0053] For plants with uniform rectangular distribution, the average volume of fluid per unit horizontal bed surface is At this time, the unit bed surface should be the unit horizontal bed surface, not the unit bed surface on the actual slope. The vegetation water blocking area is taken as the projection area along the water flow direction. For the vegetation array on the slope, the average water blocking area of ​​the vegetation on the unit horizontal bed surface is The average hydraulic radius of the vegetation unit horizontal plane on the slope can be obtained as

[0054] Step 7: Determine the flow resistance coefficient of rigid vegetation in the main trough area

[0055] For rigid vegetation with many branches, after introducing the above volume correction coefficient α, the water flow resistance of a single rigid vegetation can be expressed as In the formula, C a is the water flow resistance coefficient of the rigid vegetation in the slope area, ρ is the fluid density, and other parameters are defined as before. Assuming that the bed surface is smooth, the following calculation relationship is obtained for the entire water body in the vegetation area based on the force balance: Where L is the length of the vegetation area, which can be measured by indoor experiments. Then the average resistance coefficient of the prototype rigid vegetation on the slope is The calculation formula for the resistance coefficient expressed in terms of the average hydraulic radius described in step 6 is:

[0056] like Figure 2 This is a test model diagram of the present application, and the specific steps of the embodiment are as follows:

[0057] Step 1: First, select typical branched rigid plants in the plain river channel of the lower reaches of the Yangtze River as prototype test objects, trim the plants to ensure that the length of the branches is as consistent as possible, measure the stem diameter d of the experimental objects, and calculate the horizontal cross-sectional area A d It should be noted that in order to conduct comparative tests, smooth cylindrical rods with the same stem diameter and height should be selected as control test objects. Secondly, the longitudinal and transverse stem center distances of adjacent rigid vegetation in the indoor open channel water tank and the number of vegetation per unit bed surface were measured and recorded as S1, S2 and N respectively. The distribution density β of branched rigid vegetation is calculated.

[0058] Step 2: First, in the open channel flume, measure the width B of the test flume, the bottom slope θ, and the corresponding gradient J. Second, measure the submerged volume W of the prototype plant at the corresponding water depth. Similarly, measure the submerged volume W of the control test object at the same water depth. a In addition, the average flow velocity V of the observation section of the prototype test object is obtained through the water tank test. The volume correction coefficient α of branching rigid vegetation is calculated.

[0059] Step 3: Based on the experimentally measured vegetation height h m , the maximum water depth is h max and the slope angle θ, we can get the bottom elevation z of the i-th plant i =iS2tanθ.

[0060] Step 4: Based on the results of steps 1 to 3 above and the measured parameter data, define the number of rows of flooded vegetation p and the number of rows of completely flooded vegetation q, respectively. Calculate the average submerged depth of branching rigid vegetation in slope areas

[0061] Step 5: Based on the results of steps 1 to 4 above and the average flow velocity V of the section where the branched rigid vegetation is located, The corresponding average flow velocity V between vegetation stems can be obtained v .

[0062] Step 6: Based on the results of steps 1 to 5 above and the measured parameter data, The corresponding average flow velocity between vegetation stems r can be obtained v .

[0063] Step 7: Based on the results of steps 1 to 6 above and the measured vegetation area length L, The corresponding average flow velocity between vegetation stems can be obtained In the past, different scholars obtained the fitting formula C of the water flow resistance coefficient of rigid vegetation in slope area through research data. d =21.48exp(-8.657Re v ×10 -5 )+1.187exp(-2.04Re v ×10 -7 ), with accuracy, the calculation results obtained in this application are compared with the calculation results obtained by the above fitting formula, and the fitting curve is drawn as shown Figure 3 shown.

[0064] The embodiment of the present application provides a system for calculating the water flow resistance of branching rigid vegetation in a slope area by averaging, comprising:

[0065] A correction coefficient determination module is used to determine the correction coefficient of the rigid vegetation volume in the slope area;

[0066] Rigid vegetation area density calculation module, used to determine the rigid vegetation area density in the slope area;

[0067] Bottom elevation calculation module, used to determine the bottom elevation of any rigid vegetation in the slope area;

[0068] Average flooding depth calculation module, used to determine the average flooding depth of rigid vegetation in slope areas;

[0069] Average flow velocity calculation module, used to determine the average flow velocity between the main stems of rigid vegetation in the slope area;

[0070] Hydraulic radius calculation module, used to determine the hydraulic radius of rigid vegetation in the slope area;

[0071] The water flow resistance coefficient calculation module is used to determine the water flow resistance coefficient of rigid vegetation in the slope area.

[0072] An embodiment of the present application provides a computer-readable storage medium storing a program code. When the program code is executed by a processor, the steps of the method for calculating the water flow resistance of branching rigid vegetation in a slope area by averaging processing as described above are implemented.

[0073] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0074] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0075] These computer program instructions may also be stored in a computer readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0076] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0077] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0078] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0079] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0080] The above description is only an embodiment of the present application and is not intended to limit the protection scope of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for calculating the water flow resistance of branching rigid vegetation in slope areas by averaging, characterized in that: The following steps are involved: Step 1: Determine the volume correction coefficient of rigid vegetation in the slope area; Step 2: Determine the rigid vegetation area density in the slope area; Step 3: Determine the bottom elevation of any rigid vegetation in the slope area; Step 4: Determine the average inundation depth of rigid vegetation in the slope area; Step 5: Determine the average flow velocity between the main stems of rigid vegetation in the slope area; Step 6: Determine the hydraulic radius of the rigid vegetation in the slope area; Step 7: Determine the water flow resistance coefficient of the rigid vegetation in the slope area.

2. The method for calculating the water flow resistance of branching rigid vegetation in slope area by averaging processing as claimed in claim 1, characterized in that: The above-mentioned correction coefficient for the volume of rigid vegetation in the slope area is as follows: for a single rigid vegetation with many branches, the actual water blocking area A a There is a certain conversion relationship between the water blocking area A of the trunk and the volume correction coefficient α of the branching rigid vegetation, then A a =αA, which represents the projection area of ​​a single rigid plant with many branches on the water surface. The volume correction coefficient α of branched rigid vegetation is expressed by the ratio of the volume of vegetation to the volume of a cylindrical rod with the same diameter under the same flooding conditions, that is, Where W is the submerged volume of rigid vegetation under a certain flooding depth; W a is the flooded volume of the cylindrical rod under the same flooding depth, W and W a All of them can be calculated through indoor experimental measurements.

3. The method for calculating the water flow resistance of branching rigid vegetation in slope area by averaging processing as claimed in claim 2, characterized in that: The determination of the rigid vegetation area density in the slope area is specifically as follows: the rigid vegetation area density β in the slope area represents the area occupied by the rigid vegetation stems on the unit bed surface. For a rectangular uniformly distributed vegetation array, the density is given by To calculate, where S1 and S2 represent the longitudinal and transverse center distances of adjacent vegetation stems, respectively, and A d It is the horizontal cross-sectional area of ​​a single plant, measured through indoor experiments.

4. The method for calculating the water flow resistance of branching rigid vegetation in slope area by averaging processing as claimed in claim 3, characterized in that: The method of determining the bottom elevation of any rigid vegetation in the slope area is as follows: for a uniformly distributed vegetation array, the vegetation height is defined as h m , the maximum water depth is h max , obtained through indoor experimental measurement, it is believed that the elevation at the foot of the slope is z0 = 0, and the elevation of the vegetation at the top of the slope is z n , n is the number of vegetation rows, the elevation difference between adjacent plants on the same section is Δz = S2tanθ, θ is the slope angle, for a uniformly distributed vegetation array, starting from the lowest elevation, the bottom elevation z of the i-th plant i =iS2tanθ, if z i If the vegetation at the location is flooded, then there is h max -z i =h max -iS2tanθ>0, that is, i<h max / S2tanθ, where the slope foot is obtained through indoor experimental measurement.

5. The method for calculating the water flow resistance of branching rigid vegetation in slope area by averaging processing as claimed in claim 4, characterized in that: The determination of the average submerged depth of rigid vegetation in the slope area is specifically as follows: i The vegetation at the site is divided into (1) elevation z according to the flooding situation i If the vegetation is not flooded, then h max -z i ≤0; (2) Elevation z i If the vegetation is partially flooded, then 0≤h max -z i ≤h m ; (3) Elevation z i If the vegetation is completely flooded, then h max -z i ≥h m , define p as the number of rows of flooded vegetation, then The largest integer with p≤n, if z i If all vegetation at the location is submerged, then h max -(z i +h m )≥0, define q as the number of vegetation rows that are completely submerged, and q as the number that satisfies and q≤n is the largest positive integer. According to the above definitions of p and q, the total submerged depth of vegetation is The average inundation depth of vegetation is known 6. The method for calculating the water flow resistance of branching rigid vegetation in slope area by averaging processing as claimed in claim 5, characterized in that: The determination of the average flow velocity between the main stems of the rigid vegetation in the slope area is carried out by using an averaging method due to the existence of the slope. For the water body on the unit horizontal bed surface, its average depth is half of the maximum water depth, that is, For the flow area A', the flow area of ​​water on the unit bed surface is A' = Bh, which is obtained by subtracting the cross-sectional area from the effective water blocking area of ​​vegetation. a -αβ·Bh a =(1-αβ)·Bh a , where B is the width of the main groove area, h a is the flooding depth of the vegetation, measured through indoor experiments, and the average flow velocity between the main stems of rigid vegetation is Where V is the average flow velocity in the section where the rigid vegetation is located. The actual flow area of ​​the water flow is obtained through indoor experimental measurements. The average flow velocity between vegetation stems is 7. The method for calculating the water flow resistance of branching rigid vegetation in slope area by averaging processing as claimed in claim 6, characterized in that: The specific method for determining the hydraulic radius of rigid vegetation in the slope area is as follows: for uniformly distributed rectangular plants, the average volume of fluid per unit horizontal bed surface is At this time, the unit bed surface should be the unit horizontal bed surface, not the unit bed surface on the actual slope. The vegetation water blocking area is taken as the projection area along the water flow direction. For the vegetation array on the slope, the average water blocking area of ​​the vegetation on the unit horizontal bed surface is The average hydraulic radius of the vegetation unit horizontal plane on the slope can be obtained as 8. The method for calculating the water flow resistance of branching rigid vegetation in slope area by averaging processing as claimed in claim 7, characterized in that: The determination of the flow resistance coefficient of the rigid vegetation in the main trough area is specifically as follows: for rigid vegetation with many branches, after introducing the volume correction coefficient α, the flow resistance of a single rigid vegetation can be expressed as In the formula, C a is the water flow resistance coefficient of the rigid vegetation in the slope area, ρ is the fluid density, and assuming that the bed surface is smooth, the following calculation relationship is obtained for the entire water body in the vegetation area based on the force balance: Where L is the length of the vegetation area, which is measured through indoor experiments. The average resistance coefficient of the prototype rigid vegetation on the slope is The calculation formula of the resistance coefficient expressed in terms of the average hydraulic radius is:

9. A system for calculating the water flow resistance of branching rigid vegetation in slope areas by averaging, characterized in that: include, A correction coefficient determination module is used to determine the correction coefficient of the rigid vegetation volume in the slope area; Rigid vegetation area density calculation module, used to determine the rigid vegetation area density in the slope area; Bottom elevation calculation module, used to determine the bottom elevation of any rigid vegetation in the slope area; Average flooding depth calculation module, used to determine the average flooding depth of rigid vegetation in slope areas; Average flow velocity calculation module, used to determine the average flow velocity between the main stems of rigid vegetation in the slope area; Hydraulic radius calculation module, used to determine the hydraulic radius of rigid vegetation in the slope area; The water flow resistance coefficient calculation module is used to determine the water flow resistance coefficient of rigid vegetation in the slope area.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores program codes, and when the program codes are executed by a processor, the steps of the method for calculating the water flow resistance of branch-type rigid vegetation in a slope area by averaging processing as described in any one of claims 1 to 8 are implemented.

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