River evolution scale prediction method based on section terrain and related equipment

Abstract

The invention discloses a river evolution scale prediction method based on section topography and related equipment. The method comprises the following steps: acquiring observation data of a target river reach at a plurality of measurement times, and operating years of a dam of the target river reach at the corresponding measurement times; according to the observation data, flat beach river channel form parameters of each section in the target river reach at the corresponding measurement times are determined; determining a first calculation formula of the flat beach river channel morphological parameters, wherein the first calculation formula comprises a flat beach river channel morphological parameter balance value of the river reach scale and a flat beach river channel morphological parameter attenuation coefficient of the river reach scale; and determining a flat beach channel form adjustment mode and a time scale of the target river reach based on the flat beach channel form parameter of the target river reach in the river reach scale, the flat beach channel form parameter balance value of the river reach scale and the flat beach channel form parameter attenuation coefficient of the river reach scale, and obtaining a flat beach channel form evolution scale prediction result. The prediction cost and the prediction difficulty of the river channel form evolution rule of the downstream river channel of the reservoir can be reduced.

Description

Technical Field

[0001] The present application relates to the fields of river evolution simulation, river regulation and protection, and specifically relates to a method for predicting the scale of river evolution based on cross-sectional topography and related equipment. Background Art

[0002] After the construction and operation of a dam on an alluvial river, under the influence of sediment trapping in the reservoir, the water and sediment regime entering the downstream river channel is completely changed, the sediment concentration of the discharged water flow is significantly reduced, and the material supplement is insufficient, resulting in a long-term non-equilibrium scouring and adjustment process in the downstream river channel of the reservoir. However, the strong scouring of the downstream river channel may damage the dike structure and threaten flood control safety and ecological health. Therefore, predicting the river channel morphology of the downstream river channel of the reservoir is an urgent problem to be solved currently.

[0003] In related technologies, the prediction of the river channel morphology of the downstream river channel of the reservoir can be realized based on methods such as physical model tests. However, physical model tests are restricted by the size of the site, with high costs and difficulty in continuous implementation. It can be seen that currently, both the prediction cost and prediction difficulty of the river channel morphology of the downstream river channel of the reservoir are relatively high. Summary of the Invention

[0004] Embodiments of the present application provide a method for predicting the scale of river evolution based on cross-sectional topography and related equipment, aiming to reduce the prediction cost and prediction difficulty of the evolution law of the river channel morphology of the downstream river channel of the reservoir.

[0005] On the one hand, the present application provides a method for predicting the scale of river evolution based on cross-sectional topography, and the method includes: Obtain the observation data of the target river reach at multiple measurement times, and the operation years of the dam of the target river reach at the corresponding measurement times, where the observation data includes the starting distances and riverbed elevations of multiple observation points at multiple cross-sections in the target river reach at the corresponding measurement times; Determine the flat flood channel morphology parameters of each cross-section in the target river reach according to the observation data; Determine the first calculation formula for the flat flood channel morphology parameters, where the first calculation formula includes the equilibrium value of the flat flood channel morphology parameters at the river reach scale and the attenuation coefficient of the flat flood channel morphology parameters at the river reach scale, both of which are calibrated based on the flat flood channel morphology parameters of all cross-sections in the target river reach at all measurement times and the operation years of the dam; Based on the flat flood channel morphology parameters at the river reach scale, the equilibrium value of the flat flood channel morphology parameters at the river reach scale, and the attenuation coefficient of the flat flood channel morphology parameters at the river reach scale of the target river reach, determine the adjustment mode and time scale of the flat flood channel morphology of the target river reach, and obtain the prediction result of the flat flood channel morphology evolution scale.

[0006] In some embodiments, the floodplain channel morphological parameters at the river reach scale include the floodplain cross-sectional area, floodplain water depth, and floodplain river width at the river reach scale, and the equilibrium values of the floodplain channel morphological parameters at the river reach scale include the equilibrium value of the floodplain cross-sectional area, the equilibrium value of the floodplain water depth, and the equilibrium value of the floodplain river width; The adjustment mode of the floodplain channel morphology of the target river reach is determined through the following steps: According to the equilibrium values of the floodplain channel morphological parameters at the river reach scale and the initial values of the floodplain channel morphological parameters at the river reach scale, determine the relative adjustment intensity of the floodplain channel morphological parameters at the river reach scale, and the relative adjustment intensity includes the relative adjustment intensity of the floodplain cross-sectional area, the relative adjustment intensity of the floodplain water depth, and the relative adjustment intensity of the floodplain river width; Based on the relative adjustment intensity of the floodplain cross-sectional area, the relative adjustment intensity of the floodplain water depth, and the relative adjustment intensity of the floodplain river width, determine the adjustment mode of the floodplain channel morphology.

[0007] In some embodiments, the determining the adjustment mode of the floodplain channel morphology based on the relative adjustment intensity of the floodplain cross-sectional area, the relative adjustment intensity of the floodplain water depth, and the relative adjustment intensity of the floodplain river width includes: Determine a radar chart among the relative adjustment intensity of the floodplain cross-sectional area, the relative adjustment intensity of the floodplain water depth, and the relative adjustment intensity of the floodplain river width; Coordinate the vertices in the radar chart to respectively determine the coordinate points of the relative adjustment intensity of the floodplain water depth, the coordinate points of the relative adjustment intensity of the floodplain river width, and the vector between the center point of the radar chart and the coordinate origin; Based on the coordinate points of the relative adjustment intensity of the floodplain water depth, the coordinate points of the relative adjustment intensity of the floodplain river width, and the vector between the center point of the radar chart and the coordinate origin, determine the adjustment mode of the floodplain channel morphology, and the adjustment mode of the floodplain channel morphology includes at least one of downcutting adjustment, widening adjustment, and comprehensive adjustment.

[0008] In some embodiments, the determining the adjustment mode of the floodplain channel morphology based on the coordinate points of the relative adjustment intensity of the floodplain water depth, the coordinate points of the relative adjustment intensity of the floodplain river width, and the vector between the center point of the radar chart and the coordinate origin includes: Determine the first cross product value between the vector of the coordinate point of the relative adjustment intensity of the floodplain water depth and the coordinate origin and the vector of the center point of the radar chart and the coordinate origin; Determine the second cross product value between the vector of the coordinate point of the relative adjustment intensity of the floodplain river width and the coordinate origin and the vector of the center point of the radar chart and the coordinate origin; Determine the first ratio between the modulus of the vector of the coordinate point of the relative adjustment intensity of the floodplain water depth and the coordinate origin and the modulus of the vector of the coordinate point of the relative adjustment intensity of the floodplain river width and the coordinate origin; Determine the adjustment mode of the flat beach river channel morphology based on the positive and negative of the first cross product value and the second cross product value and the magnitude of the first ratio.

[0009] In some embodiments, the adjustment time scale of the flat beach river channel morphology of the target river reach is determined through the following steps: For the target river reach, determine the quantitative relationship between the attenuation coefficient of the flat beach river channel morphology parameters at the reach scale and the adjustment equilibrium time of the flat beach river channel morphology parameters at the reach scale; Input the attenuation coefficient of the flat beach river channel morphology parameters at the reach scale into the quantitative relationship to determine the adjustment equilibrium time of the flat beach river channel morphology parameters at the reach scale. The adjustment time scale of the flat beach river channel morphology includes the adjustment equilibrium time of the flat beach river channel morphology parameters at the reach scale, and the adjustment equilibrium time of the flat beach river channel morphology parameters at the reach scale includes the adjustment equilibrium time of the flat beach cross-sectional area, the flat beach water depth, and the flat beach river width at the reach scale.

[0010] In some embodiments, the determining the quantitative relationship between the attenuation coefficient of the flat beach river channel morphology parameters at the reach scale and the adjustment equilibrium time of the flat beach river channel morphology parameters at the reach scale for the target river reach includes: For each cross-section in the target river reach, determine the second calculation formula for the flat beach river channel morphology parameters, where the second calculation formula includes the equilibrium value of the flat beach river channel morphology parameters at the cross-section scale and the attenuation coefficient of the flat beach river channel morphology parameters at the cross-section scale, both of which are calibrated based on the flat beach river channel morphology parameters at the corresponding cross-section in the target river reach at the cross-section scale and the operation years of the dam. For each cross-section in the target river reach, determine the time corresponding to the adjustment amount of the flat beach river channel morphology parameters at the corresponding cross-section in the target river reach reaching the target adjustment amount, and use it as the initially proposed adjustment equilibrium time. The target adjustment amount is determined based on the difference between the equilibrium value of the flat beach river channel morphology parameters at the corresponding cross-section in the target river reach at the cross-section scale and the initial value of the flat beach river channel morphology parameters at the corresponding cross-section in the target river reach. According to the attenuation coefficient of the flat beach river channel morphology parameters at the cross-section scale and the initially proposed adjustment equilibrium time of all cross-sections in the target river reach, determine the quantitative relationship.

[0011] In some embodiments, the determining the quantitative relationship according to the attenuation coefficient of the flat beach river channel morphology parameters at the cross-section scale and the initially proposed adjustment equilibrium time of all cross-sections in the target river reach includes: Generate a scatter plot of the relationship between the attenuation coefficient of the flat beach river channel morphology parameters at the cross-section scale and the initially proposed adjustment equilibrium time of all cross-sections in the target river reach; Determine the upper and lower envelope lines in the scatter plot; Take the average value of the data of the upper and lower envelopes, and then perform curve fitting to obtain the quantitative relationship.

[0012] In some embodiments, the first calculation formula is determined by the following formula:

[0013] Where is the value of the flat beach river channel morphological parameter at (x, t), x is the mileage from the dam of the corresponding cross-section in the target river reach, t is the operation years of the dam, and Y e is the corresponding equilibrium value of the flat beach river channel morphological parameter, Φ(x, t) is the flat beach river channel morphological boundary function, and Φ e is the flat beach river channel morphological boundary equilibrium value function, e is the natural constant, α is the attenuation coefficient of the corresponding flat beach river channel morphological parameter, v is the propagation rate of the change of the corresponding flat beach river channel morphological parameter in space, and t0 is the initial value of the operation years of the dam.

[0014] On the other hand, the embodiments of the present application provide a device for predicting the scale of river channel evolution based on cross-sectional topography, including: The first acquisition module is used to acquire the observation data of the target river reach at multiple measurement times, and the operation years of the dam of the target river reach at the corresponding measurement times. The observation data includes the starting distances and riverbed elevations of multiple observation points at multiple cross-sections in the target river reach at the corresponding measurement times; The first determination module is used to determine the flat beach river channel morphological parameter of each cross-section in the target river reach at the corresponding measurement time according to the observation data; The second determination module is used to determine the first calculation formula of the flat beach river channel morphological parameter. Among them, the first calculation formula includes the equilibrium value of the flat beach river channel morphological parameter at the river reach scale and the attenuation coefficient of the flat beach river channel morphological parameter at the river reach scale, both of which are calibrated based on the flat beach river channel morphological parameters of all cross-sections in the target river reach at all measurement times and the operation years of the dam; The third determination module is used to determine the adjustment mode and time scale of the flat beach river channel morphology of the target river reach based on the flat beach river channel morphological parameter at the river reach scale, the equilibrium value of the flat beach river channel morphological parameter at the river reach scale, and the attenuation coefficient of the flat beach river channel morphological parameter at the river reach scale, and obtain the prediction result of the scale of flat beach river channel morphological evolution.

[0015] On the other hand, the present application also provides a computer device, and the computer device includes: One or more processors; A memory; and One or more applications, wherein the one or more applications are stored in the memory and configured to be executed by the processor to implement the steps in any one of the methods for predicting the scale of river channel evolution based on cross-sectional topography.

[0016] On the other hand, the present application also provides a computer-readable storage medium, on which a computer program is stored. The computer program is loaded by the processor to execute the steps in any one of the methods for predicting the scale of river channel evolution based on cross-sectional topography.

[0017] On the other hand, an embodiment of the present application provides a computer program product, including a computer program or instruction, and the computer program or instruction is executed by the processor to implement the method for predicting the scale of river channel evolution based on cross-sectional topography as described in any one of the above.

[0018] The method for predicting the scale of river channel evolution based on cross-sectional topography and related devices provided by the embodiments of the present application obtain the observation data of the target river reach at multiple measurement times and the operation years of the dam of the target river reach at the corresponding measurement times; according to the observation data, determine the flat flood channel morphology parameters of each cross-section in the target river reach at the corresponding measurement times; determine the first calculation formula for the flat flood channel morphology parameters, where the first calculation formula includes the equilibrium value of the flat flood channel morphology parameters at the river reach scale and the attenuation coefficient of the flat flood channel morphology parameters at the river reach scale, both of which are calibrated based on the flat flood channel morphology parameters of all cross-sections in the target river reach at all measurement times and the operation years of the dam; based on the flat flood channel morphology parameters at the river reach scale, the equilibrium value of the flat flood channel morphology parameters at the river reach scale, and the attenuation coefficient of the flat flood channel morphology parameters at the river reach scale of the target river reach, determine the adjustment mode and time scale of the flat flood channel morphology of the target river reach, and obtain the prediction result of the scale of flat flood channel morphology evolution. By using the observation data of the target river reach at multiple measurement times and the operation years of the dam, the embodiments of the present application can accurately predict the evolution law of the river channel morphology downstream of the reservoir. Compared with the method of predicting the evolution law of the river channel morphology downstream of the reservoir based on physical model tests and other methods, the prediction cost and prediction difficulty are lower. Description of the Drawings

[0019] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present application. For those skilled in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0020] Figure 1 It is a schematic diagram of an embodiment of the method for predicting the scale of river channel evolution based on cross-sectional topography provided in the embodiments of the present application; Figure 2It is a schematic diagram of the evolution process of the cross-section channel shape parameters at the river reach scale of river reach a provided in the embodiments of the present application for multiple measurement times; Figure 3 It is a schematic diagram of the evolution process of the cross-section channel shape parameters at the river reach scale of river reach b provided in the embodiments of the present application for multiple measurement times; Figure 4 It is a radar chart (unit: %) of the relative adjustment intensity of the cross-section channel shape parameters of river reach a in the embodiments of the present application; Figure 5 It is a radar chart (unit: %) of the relative adjustment intensity of the cross-section channel shape parameters of river reach b in the embodiments of the present application; Figure 6 It is a schematic structural diagram of an embodiment of a river channel evolution scale prediction device based on cross-section topography provided in the embodiments of the present application; Figure 7 It is a schematic terminal structure diagram of an embodiment of a computer device provided in the embodiments of the present application. Detailed implementation manners

[0021] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts fall within the protection scope of the present application.

[0022] In the description of the present application, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of the described features. In the description of the present application, "a plurality of" means two or more unless otherwise specifically defined.

[0023] In the present application, the phrase "in some embodiments" is used to mean "serving as an example, illustration, or description". Any embodiment described as "in some embodiments" in the present application is not necessarily construed as being more preferred or having more advantages than other embodiments. In order for any person skilled in the art to implement and use the present application, the following description is given. In the following description, details are set forth for purposes of explanation. It should be understood that those skilled in the art can recognize that the present application can be implemented without using these specific details. In other instances, well-known structures and processes are not elaborated in detail to avoid obscuring the description of the present application with unnecessary details. Therefore, the present application is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed in the present application.

[0024] It should be noted that since the system of the embodiments of the present application is executed in a computer device, the processing objects of each computer device exist in the form of data or information. For example, time, which is actually time information. It can be understood that in subsequent embodiments, if dimensions, quantities, positions, etc. are mentioned, they are all corresponding data existences for the computer device to process, and specific details are not elaborated here.

[0025] The embodiments of the present application provide a method for predicting the evolution scale of a river channel based on cross-sectional topography, related devices. Based on long-term measured large cross-section data, through the standardization processing of measured large cross-section observation data, the construction of a dataset of target reach flat flood channel morphological parameters, and the calculation of flat flood channel morphological evolution characteristic values, the automatic calculation of the flat flood channel morphological adjustment mode and time scale of non-equilibrium alluvial rivers is realized. The results of the embodiments of the present application can be widely used for the rapid and accurate discrimination of the evolution trend of river channels in multiple fields such as riverbed evolution prediction, river channel regulation and protection. The following will be described in detail respectively.

[0026] In one embodiment, referring to Figure 1 , the method for predicting the evolution scale of a river channel based on cross-sectional topography includes: 101. Obtain the observation data of the target reach at multiple measurement times, and the operation years of the dam of the target reach at the corresponding measurement times. The observation data includes the starting distance and riverbed elevation of multiple observation points at multiple cross-sections in the target reach at the corresponding measurement times.

[0027] In the embodiments of the present application, the target reach is usually located downstream of the dam. That is, under the influence of the reservoir sediment interception operation of the dam, the water and sediment regime entering the downstream target reach will be changed. Therefore, it is necessary to predict the evolution law of the flat flood channel morphology of the target reach.

[0028] In some embodiments of the present application, an example is given to illustrate the refined content of step 101. Specifically, step 101 may include: Step 1. Standardization processing of long-term measured large cross-section observation data.

[0029] 1.1. Sort out the long-term measured large cross-section observation data of the target reach. For the data of a certain measurement time, set the number of cross-sections as mm, the number of cross-section observation points as nn, and the number of measurement times as yy. Then the topographic data can be expressed as: X (i, j), Y(i, j), T(k) In the formula, X is the distance from the observation point to the starting point of the cross-section, that is, the starting distance; Y is the measured riverbed elevation of the observation point; T is the operation years of the dam corresponding to the observation time of each measurement time; i is the measurement cross-section number; j is the maximum value of the number of observation points of each cross-section; k is the number of measurement times. Where i = 1, 2,..., mm; j = 1, 2,..., nn; k = 1, 2,..., yy.

[0030] 1.2 Standardization of long-sequence measured large cross-section observation data. The topographic data of different measured large cross-sections in the same measurement are stored in the same Excel file in the format of starting distance X and elevation Y, while the data of different measurement times are stored in different Excel files named by the measurement sequence number, and the cross-section observation time T is stored in the Excel file named by time.

[0031] 102. According to the observation data, determine the floodplain channel morphological parameters of each cross-section in the target river reach at the corresponding measurement time.

[0032] In the embodiments of the present application, the floodplain channel morphological parameters of each cross-section in the target river reach refer to the parameters used to characterize the floodplain channel morphology of the corresponding cross-section in the target river reach. The floodplain channel morphological parameters Y of each cross-section in the target river reach may include, for example, the floodplain cross-sectional area A, the floodplain water depth H, and the floodplain river width B of the corresponding cross-section in the target river reach. Each cross-section in the target river reach corresponds to a set of floodplain channel morphological parameters at each measurement time.

[0033] In some embodiments of the present application, according to the observation data, determining the floodplain channel morphological parameters of each cross-section in the target river reach at the corresponding measurement time may include: obtaining the floodplain water level of each cross-section in the target river reach at the corresponding measurement time; and determining the floodplain channel morphological parameters of each cross-section in the target river reach at the corresponding measurement time according to the floodplain water level and the observation data. Taking the floodplain river width of the cross-section as an example, for each cross-section, the geometric shape of the cross-section can be determined by using the starting distance and the riverbed elevation of multiple observation points in this measurement time, and the width of the geometric shape of the cross-section at the floodplain water level is used as the floodplain river width. Taking the floodplain cross-sectional area of the cross-section as an example, the area of the part of the geometric shape of the cross-section below the floodplain water level can be used as the floodplain cross-sectional area (this floodplain cross-sectional area can be calculated by the trapezoidal area summation method of adjacent observation points according to the starting distance and the riverbed elevation of multiple observation points in this measurement time of the cross-section). Taking the floodplain water depth of the cross-section as an example, the ratio of the floodplain cross-sectional area of the cross-section to the floodplain river width of the cross-section can be used as the floodplain water depth of the cross-section.

[0034] In some embodiments of the present application, after step 102, it may further include: for each measurement time, according to the floodplain channel morphological parameters of multiple cross-sections in the target river reach at the corresponding measurement time (which may include, for example, the floodplain cross-sectional area, the floodplain water depth, and the floodplain river width of each cross-section in the target river reach at this measurement time), calculate using the spatial weighted average algorithm to obtain the floodplain channel morphological parameters at the river reach scale of the target river reach at the corresponding measurement time. For example, the change value of the mileage from the dam of adjacent cross-sections in the target river reach (i.e., the distance between adjacent cross-sections) can be used as the weight to perform weighted average on the floodplain channel morphological parameters of multiple cross-sections at this measurement time to obtain the floodplain channel morphological parameters at the river reach scale of the target river reach at this measurement time.

[0035] Among them, the floodplain channel morphological parameters of the target river reach at the reach scale refer to the parameters used to characterize the floodplain channel morphology of the target river reach at the reach scale. The floodplain channel morphological parameter Y of the target river reach at the reach scale may include, for example, the floodplain cross-sectional area A, the floodplain water depth H, and the floodplain river width B of the target river reach at the reach scale. Each measurement of the target river reach corresponds to a set of floodplain channel morphological parameters at the reach scale.

[0036] In some embodiments of the present application, the refinement content of step 102 is illustrated by way of example. Specifically, step 102 may include: Step 2, constructing a dataset of floodplain channel morphological parameters for all cross-sections in the target river reach.

[0037] 2.1, identifying the floodplain water level Z and the floodplain river width B of each measured large cross-section in each measurement of the target river reach, and using the trapezoidal area summation method of adjacent observation points with a for loop statement in MATLAB to sequentially calculate the main channel cross-sectional area under the floodplain water level, that is, the floodplain cross-sectional area A, and calculate the floodplain water depth H = A / B.

[0038] After step 102, it may further include: 2.2, using the spatial weighted average method for the floodplain channel morphological parameters of multiple cross-sections in the target river reach at the corresponding measurement to calculate the floodplain channel morphological parameter data at the reach scale of the corresponding measurement.

[0039] 2.3, recording the values of the floodplain cross-sectional area A, the floodplain water depth H, and the floodplain river width B at the reach scale of the first measurement of the target river reach as the initial values A0, H0, and B0 of the floodplain channel morphological parameters at the reach scale.

[0040] 2.4, constructing a dataset of floodplain channel morphological parameters at the reach scale including the floodplain cross-sectional area A, the floodplain water depth H, the floodplain river reach B, and the dam operation years T.

[0041] 103. Determine the first calculation formula for the floodplain channel morphological parameters, where the first calculation formula includes the equilibrium value of the floodplain channel morphological parameters at the reach scale and the attenuation coefficient of the floodplain channel morphological parameters at the reach scale, both of which are calibrated based on the floodplain channel morphological parameters of all cross-sections in the target river reach at all measurements and the operation years of the dam.

[0042] In the embodiments of the present application, the first calculation formula of the floodplain channel morphological parameters of the target river reach characterizes the correlation between the floodplain channel morphological parameters of the target river reach and the dam operation years, that is, the relationship between the floodplain channel morphological parameters of the target river reach and the change of the dam operation years. Since the floodplain channel morphological parameters of the target river reach tend to be stable and reach an equilibrium state after changing for a certain period of time, the first calculation formula includes the equilibrium value of the floodplain channel morphological parameters at the river reach scale and the attenuation coefficient of the floodplain channel morphological parameters at the river reach scale. The equilibrium value of the floodplain channel morphological parameters at the river reach scale refers to the floodplain channel morphological parameters when the floodplain channel of the target river reach reaches an equilibrium state. The attenuation coefficient of the floodplain channel morphological parameters at the river reach scale characterizes the attenuation of the floodplain channel morphological parameters of the target river reach. The equilibrium value of the floodplain channel morphological parameters at the river reach scale and the attenuation coefficient of the floodplain channel morphological parameters at the river reach scale can both be calibrated based on the floodplain channel morphological parameters of all cross-sections in the target river reach at all measurement times and the operation years of the dam.

[0043] In some embodiments of the present application, the first calculation formula of the floodplain channel morphological parameters of the target river reach is determined, for example, by the following formula:

[0044] Wherein, is the value of the floodplain channel morphological parameter at (x, t), x is the mileage from the dam of the corresponding cross-section in the target river reach, t is the operation years of the dam, and Y e is the corresponding equilibrium value of the floodplain channel morphological parameter, Φ(x, t) is the floodplain channel morphological boundary function, and Φ e is the equilibrium value of the floodplain channel morphological boundary function, e is the natural constant, α is the corresponding attenuation coefficient of the floodplain channel morphological parameter, v is the propagation rate of the change of the corresponding floodplain channel morphological parameter in space, and t0 is the initial value of the operation years of the dam. α and Y e can be calibrated based on the floodplain channel morphological parameters of all cross-sections in the target river reach at all measurement times and the operation years of the dam at multiple measurement times. The calibration method can be, for example, the least squares method.

[0045] In some embodiments of the present application, the refinement content of step 103 is illustrated by examples. Specifically, step 103 may include: Step 3, calculate the characteristic values of the floodplain channel morphological evolution scale of the target river reach.

[0046] 3.1, construct the calculation methods for the evolution scales in the transverse, longitudinal, and cross-section dimensions of the floodplain channel.

[0047] The prediction control equation for the floodplain channel morphological evolution scale is as follows:

[0048] In the formula, is the value of the flat beach channel form parameter (including the flat beach cross-sectional area A, flat beach water depth H, and flat beach river width B of the corresponding cross-section in the target reach) at (x, t); x is the mileage from the dam of the corresponding cross-section in the target reach, and t is the operation years of the dam; v is the propagation rate of the change of the flat beach channel form parameter in space; α is the attenuation coefficient of the corresponding flat beach channel form parameter; Y e is the equilibrium value of the corresponding flat beach channel form parameter (including the equilibrium value A of the flat beach cross-sectional area e of the target reach at the reach scale, the equilibrium value H e of the flat beach water depth, and the equilibrium value B e of the flat beach river width).

[0049] The above control equation is made dimensionless and denoted as: , , ,

[0050] where the variable T e , L e , are respectively the equilibrium time, equilibrium distance, and characteristic propagation speed of the flat beach channel form evolution; τ and ξ are dimensionless parameters respectively.

[0051] Furthermore, it can be obtained that:

[0052] Solving gives:

[0053] The first calculation formula for predicting the scale of the flat beach channel form evolution is obtained by restoring the variables as follows:

[0054] where Φ(x, t) is the flat beach channel form boundary function. Considering x as a constant, this formula can predict the evolution process of the flat beach channel form parameters Y (including the flat beach cross-sectional area A, flat beach water depth H, and flat beach river width B of the target reach at the reach scale), and denote A e , H e , B eThey are the equilibrium values of the floodplain cross-sectional area, floodplain water depth, and floodplain river width at the reach scale of the target reach; A0, H0, and B0 are the initial values of the floodplain cross-sectional area, floodplain water depth, and floodplain river width at the reach scale of the target reach; α1, α2, and α3 are the attenuation coefficients of the floodplain cross-sectional area, floodplain water depth, and floodplain river width at the reach scale of the target reach, respectively. It can be seen that the above formula takes into account the evolution of the floodplain channel shape parameters of the target reach in both the time dimension and the space dimension, thus making the prediction results more accurate. 3.2 Using the for loop statement in MATLAB, the least squares method is used to sequentially determine the equilibrium values A e , H e , B e and the values of the attenuation coefficients α1, α2, and α3 (where, for the attenuation coefficient α, the attenuation coefficients of the floodplain channel shape parameters at the cross-section scale of the corresponding floodplain channel shape parameters can also be sequentially determined, as detailed in the following content).

[0055] 104. Based on the floodplain channel shape parameters at the reach scale of the target reach, the equilibrium values of the floodplain channel shape parameters at the reach scale, and the attenuation coefficients of the floodplain channel shape parameters at the reach scale, determine the adjustment mode and time scale of the floodplain channel shape of the target reach, and obtain the prediction result of the evolution scale of the floodplain channel shape.

[0056] In the embodiments of the present application, the prediction result of the evolution scale of the floodplain channel shape includes the adjustment mode of the floodplain channel shape of the target reach and the adjustment time scale of the floodplain channel shape of the target reach. The adjustment mode of the floodplain channel shape may include, for example, at least one of incision-type adjustment, widening-type adjustment, and comprehensive-type adjustment. The adjustment time scale of the floodplain channel shape may include, for example, the adjustment equilibrium time of the floodplain channel shape parameters.

[0057] In some embodiments of the present application, the adjustment mode of the floodplain channel shape of the target reach can be determined through the following steps: According to the equilibrium value of the floodplain channel shape parameters at the reach scale and the initial value of the floodplain channel shape parameters at the reach scale, determine the relative adjustment intensity of the floodplain channel shape parameters at the reach scale. For example, the difference between the equilibrium value of the floodplain channel shape parameters at the reach scale and the initial value of the floodplain channel shape parameters at the reach scale can be determined, and then the ratio between the difference and the initial value of the floodplain channel shape parameters at the reach scale can be determined and used as the relative adjustment intensity of the floodplain channel shape parameters; Based on the relative adjustment intensity, determine the adjustment mode of the floodplain channel shape of the target reach.

[0058] In some embodiments of the present application, taking the relative adjustment intensity including the relative adjustment intensity of the floodplain cross-sectional area, the relative adjustment intensity of the floodplain water depth, and the relative adjustment intensity of the floodplain river width as an example for description. Based on the relative adjustment intensity, determining the adjustment mode of the floodplain river channel morphology of the target reach may include: determining the adjustment mode of the floodplain river channel morphology based on the relative adjustment intensity of the floodplain cross-sectional area, the relative adjustment intensity of the floodplain water depth, and the relative adjustment intensity of the floodplain river width. It can be seen that in the embodiments of the present application, the evolution of the floodplain river channel of the target reach in the cross-section dimension, longitudinal direction, and transverse direction is respectively characterized by the relative adjustment intensity of the floodplain cross-sectional area, the relative adjustment intensity of the floodplain water depth, and the relative adjustment intensity of the floodplain river width, so as to more accurately predict the adjustment mode of the floodplain river channel morphology of the target reach.

[0059] In some embodiments of the present application, based on the relative adjustment intensity of the floodplain cross-sectional area, the relative adjustment intensity of the floodplain water depth, and the relative adjustment intensity of the floodplain river width, determining the adjustment mode of the floodplain river channel morphology may include: determining a radar chart (such as Figure 4 or Figure 5 the radar chart in the shown form) among the relative adjustment intensity of the floodplain cross-sectional area, the relative adjustment intensity of the floodplain water depth, and the relative adjustment intensity of the floodplain river width; coordinate the vertices in the radar chart to respectively determine the relative adjustment intensity coordinate point of the floodplain water depth, the relative adjustment intensity coordinate point of the floodplain river width, and the vector between the center point of the radar chart and the coordinate origin; based on the relative adjustment intensity coordinate point of the floodplain water depth, the relative adjustment intensity coordinate point of the floodplain river width, and the vector between the center point of the radar chart and the coordinate origin, determine the adjustment mode of the floodplain river channel morphology. For example, the adjustment mode of the floodplain river channel morphology can be judged according to the ratio between the relative adjustment intensity of the floodplain water depth and the relative adjustment intensity of the floodplain river width, and the relative adjustment intensity of the floodplain cross-sectional area can be presented in the radar chart for auxiliary judgment of the adjustment mode of the floodplain river channel morphology, more intuitively helping to judge whether the change in the floodplain cross-sectional area is mainly contributed by the floodplain river width or the floodplain water depth, and then determining the adjustment mode of the floodplain river channel morphology.

[0060] In some embodiments of the present application, to determine the adjustment mode of the flat beach river channel morphology based on the relative adjustment intensity coordinate points of the flat beach water depth, the relative adjustment intensity coordinate points of the flat beach river width, and the vector between the center point of the radar chart and the coordinate origin, it may include: determining the first cross product value between the vector of the relative adjustment intensity coordinate point of the flat beach water depth and the coordinate origin and the vector of the center point of the radar chart and the coordinate origin; determining the second cross product value between the vector of the relative adjustment intensity coordinate point of the flat beach river width and the coordinate origin and the vector of the center point of the radar chart and the coordinate origin; determining the first ratio between the modulus of the vector of the relative adjustment intensity coordinate point of the flat beach water depth and the coordinate origin and the modulus of the vector of the relative adjustment intensity coordinate point of the flat beach river width; and determining the adjustment mode of the flat beach river channel morphology based on the positive or negative of the first cross product value and the second cross product value and the magnitude of the first ratio.

[0061] In some embodiments of the present application, the adjustment time scale of the flat beach river channel morphology of the target river section can be determined through the following steps: for the target river section, determining the quantitative relationship between the attenuation coefficient of the flat beach river channel morphology parameters at the river section scale and the adjustment equilibrium time of the flat beach river channel morphology parameters at the river section scale; inputting the attenuation coefficient of the flat beach river channel morphology parameters at the river section scale into the quantitative relationship to determine the adjustment equilibrium time of the flat beach river channel morphology parameters at the river section scale. The adjustment time scale of the flat beach river channel morphology includes the adjustment equilibrium time of the flat beach river channel morphology parameters at the river section scale, and the adjustment equilibrium time of the flat beach river channel morphology parameters at the river section scale includes the adjustment equilibrium time of the flat beach cross-sectional area, the flat beach water depth, and the flat beach river width at the river section scale.

[0062] In some embodiments of the present application, for a target river reach, determining the quantitative relationship between the attenuation coefficient of the floodplain channel morphological parameters at the reach scale and the adjustment equilibrium time of the floodplain channel morphological parameters at the reach scale may include: for each cross-section in the target river reach, determining a second calculation formula for the floodplain channel morphological parameters, where the second calculation formula includes the equilibrium value of the floodplain channel morphological parameters at the cross-section scale and the attenuation coefficient of the floodplain channel morphological parameters at the cross-section scale, both of which are calibrated based on the floodplain channel morphological parameters at the corresponding cross-section in the target river reach and the operation years of the dam. The second calculation formula may refer to the first calculation formula and will not be elaborated here; for each cross-section in the target river reach, determining the time corresponding to the adjustment amount of the floodplain channel morphological parameters at the corresponding cross-section in the target river reach reaching the target adjustment amount, and using it as the preliminary adjustment equilibrium time. The target adjustment amount is determined based on the difference between the equilibrium value of the floodplain channel morphological parameters at the corresponding cross-section in the target river reach and the initial value of the floodplain channel morphological parameters at the corresponding cross-section in the target river reach. For example, the preliminary adjustment equilibrium time may be: the time required for the adjustment amount of the floodplain channel morphological parameters at the corresponding cross-section in the target river reach to reach 90% of the difference between the equilibrium value of the floodplain channel morphological parameters at the corresponding cross-section in the target river reach and the initial value of the floodplain channel morphological parameters at the corresponding cross-section in the target river reach; determining the quantitative relationship based on the attenuation coefficient of the floodplain channel morphological parameters at the cross-section scale and the preliminary adjustment equilibrium time of all cross-sections in the target river reach. For example, curve fitting can be performed based on the attenuation coefficient of the floodplain channel morphological parameters at the cross-section scale and the preliminary adjustment equilibrium time of all cross-sections in the target river reach to obtain the above-mentioned quantitative relationship. Among them, the floodplain channel morphological parameters at the cross-section scale of a single cross-section in the target river reach refer to the floodplain channel morphological parameters of this cross-section in the target river reach for all measurement times.

[0063] In some embodiments of the present application, determining the quantitative relationship based on the attenuation coefficient of the floodplain channel morphological parameters at the cross-section scale and the preliminary adjustment equilibrium time of all cross-sections in the target river reach may include: generating a scatter plot relationship diagram between the attenuation coefficient of the floodplain channel morphological parameters at the cross-section scale and the preliminary adjustment equilibrium time of all cross-sections in the target river reach; determining the upper and lower envelope lines in the scatter plot relationship diagram; taking the average value of the data of the upper and lower envelope lines and then performing curve fitting to obtain a more accurate above-mentioned quantitative relationship.

[0064] In some embodiments of the present application, the attenuation coefficient of the floodplain channel morphological parameters may include, for example, the attenuation coefficient of the floodplain cross-sectional area, the attenuation coefficient of the floodplain water depth, and the attenuation coefficient of the floodplain river width. Correspondingly, the adjustment equilibrium time of the floodplain channel morphological parameters may include the adjustment equilibrium time of the floodplain cross-sectional area, the adjustment equilibrium time of the floodplain water depth, and the adjustment equilibrium time of the floodplain river width.

[0065] In some embodiments of the present application, the refinement content of step 104 is illustrated by way of example. Specifically, step 104 may include: Step 4, analyze the adjustment mode of the floodplain channel morphology of the target river reach.

[0066] 4.1, define "relative adjustment intensity D s " as the ratio of the difference between the equilibrium value and the initial value of the floodplain channel morphology parameter to the initial value, to characterize the relative magnitude of the adjustment amplitude in different dimensions. Use the for loop statement in MATLAB to calculate the relative adjustment intensities A s 、H s 、B s of the floodplain cross-sectional area A, floodplain water depth H, and floodplain river width B of the target river reach at the reach scale.

[0067] 4.2, use the plot function in MATLAB to plot the radar charts of the relative adjustment intensities A s 、H s 、B s of the floodplain cross-sectional area, floodplain water depth, and floodplain river width of the target river reach at the reach scale.

[0068] 4.3, coordinate the vertex coordinates of the above radar chart, use the MATLAB program to calculate its center point coordinates (denoted as point D), respectively construct the vector expressions of the relative adjustment intensity coordinate points of the floodplain water depth, the relative adjustment intensity coordinate points of the floodplain river width, and the center point of the radar chart and the coordinate origin (denoted as point O), and denote them as the relative adjustment intensity vector of the floodplain water depth 、the relative adjustment intensity vector of the floodplain river width and the center vector , calculate the cross product values of the relative adjustment intensity vector of the floodplain river width 、the relative adjustment intensity vector of the floodplain water depth and the center vector respectively, as well as the modulus of the relative adjustment intensity vector of the floodplain river width 、the modulus of the relative adjustment intensity vector of the floodplain water depth .

[0069] 4.4, based on the positive or negative cross product values of the relative adjustment intensity vector of the floodplain water depth and the center vector, the positive or negative cross product values of the relative adjustment intensity vector of the floodplain river width and the center vector, and the relative magnitude relationship between the modulus of the relative adjustment intensity vector of the floodplain water depth and the modulus of the relative adjustment intensity vector of the floodplain river width, determine the adjustment mode of the floodplain channel morphology of the target river reach. For example, if and the cross product value is positive, and , then it is determined as a downcutting type of adjustment; if and the cross product value is positive and , it is determined as a widening adjustment; if it cannot be determined as a downcutting adjustment and also cannot be determined as a widening adjustment, it is determined as a comprehensive adjustment.

[0070] Step 5, predicting the morphological adjustment time scale of the target river reach's floodplain channel.

[0071] 5.1, Using the second calculation formula of the floodplain channel morphological parameters, the equilibrium values and attenuation coefficients α' of the floodplain channel morphological parameters of each dimension at each observation section in the target river reach are determined. Then, the time corresponding to the adjustment amount of the floodplain channel morphological parameters of each dimension at each observation section in the target river reach reaching 90% of the difference between its equilibrium value and the initial value is defined as the initially proposed adjustment equilibrium time T'.

[0072] 5.2, Use the plot function in MATLAB to plot the scatter relationship diagram of α'~T' for all observation sections included in the target river reach. After removing the abnormal points, determine the upper and lower envelope lines of the corresponding scatter relationship diagram.

[0073] 5.3, Export and average the grid point data of the upper and lower envelope lines, and then use power curve fitting to obtain the quantitative relationship between α and T at the river reach scale of the target river reach (i.e., T = aα b ). Considering the overall evolution characteristics of the target river reach, the statistical law of the measured sequence, and the simplicity of operation, a can be approximately taken as 2.5 and b can be approximately taken as -1, that is, T = 2.5α -1 , then the adjustment equilibrium time T1 = 2.5 / α1 for the floodplain cross-sectional area A at the river reach scale of the target river reach, the adjustment equilibrium time T2 = 2.5 / α2 for the floodplain water depth H at the river reach scale, and the adjustment equilibrium time T3 = 2.5 / α3 for the floodplain river width B at the river reach scale.

[0074] 5.4, Use the plot function in MATLAB to plot the comparison relationship of the equilibrium times T1, T2, and T3 of the floodplain cross-sectional area A, the floodplain water depth H, and the floodplain river width B at the river reach scale of the target river reach, and analyze the time scale characteristics of the cross-sectional morphology evolution of the target river reach.

[0075] In the technical solution disclosed in this embodiment, by obtaining the observation data of the target river reach at multiple measurement times, determining the flat-bottom river channel morphological parameters of each cross-section in the target river reach at the corresponding measurement times according to the observation data, and then based on the flat-bottom river channel morphological parameters and the dam operation years, determining the equilibrium value of the flat-bottom river channel morphological parameters at the river reach scale and the attenuation coefficient of the flat-bottom river channel morphological parameters at the river reach scale in the first calculation formula of the flat-bottom river channel morphological parameters of the target river reach. According to the flat-bottom river channel morphological parameters at the river reach scale, the equilibrium value of the flat-bottom river channel morphological parameters at the river reach scale, and the attenuation coefficient of the flat-bottom river channel morphological parameters at the river reach scale, determining the flat-bottom river channel morphological adjustment mode and time scale of the target river reach, and obtaining the prediction result of the flat-bottom river channel morphological evolution scale. Through the observation data of the target river reach at multiple measurement times and the dam operation years in the embodiment of the present application, the evolution law of the river channel morphology downstream of the reservoir can be accurately predicted. Compared with predicting the evolution law of the river channel morphology downstream of the reservoir based on methods such as physical model tests, the prediction cost and prediction difficulty are lower.

[0076] Next, with reference to Figure 1 , an example of the method for predicting the river channel evolution scale based on cross-section topography will be described. Specifically, two typical river reaches (denoted as river reach a and river reach b) in the middle reaches of the Yangtze River are selected as the target river reaches respectively, and the adjustment law of the flat-bottom river channel morphology of the target river reaches is analyzed, including the following steps: Step 1: Standardize the long-term measured large cross-section observation data to form a data set including the starting distance X, the riverbed elevation Y, and the observation time T.

[0077] Sort out the long-term measured large cross-section observation data of the target river reach. Store the topographic data of different measured large cross-sections at the same measurement time in the same Excel file in the format of the starting distance X and the elevation Y, as shown in Table 1 below. At the same time, store the topographic data of different measured large cross-sections at different measurement times in different Excel files named by the measurement sequence number, and store the cross-section observation time T in the Excel file named by time.

[0078] Table 1 Standardized data set of the topography of different measured large cross-sections of typical river reach a at the same measurement time

[0079] Step 2: Construct a data set of the flat-bottom river channel morphological parameters of the target river reach.

[0080] Identify the flat beach water level Z and the flat beach river width B of the measured large cross-section of the target river reach. Use the for loop statement in MATLAB to calculate the main channel cross-sectional area under the flat beach water level Z in turn by the trapezoidal area summation method of adjacent observation points, that is, the flat beach cross-sectional area A, and calculate the flat beach water depth H = A / B. Adopt spatial weighted average to calculate the flat beach river channel morphological data at the river reach scale (record the flat beach cross-sectional area, flat beach water depth, and flat beach river width of the first measurement as A0, H0, B0), and form a dataset of flat beach river channel morphological parameters including the flat beach cross-sectional area A, flat beach water depth H, flat beach river reach B, and dam operation years T, as shown in Table 2 below.

[0081] Table 2 Dataset of flat beach river channel morphological parameters of typical river reach a

[0082] Step 3: Calculate the scale characteristic values of the flat beach river channel morphological evolution of the target river reach.

[0083] Taking the two selected typical river reaches (river reach a and river reach b) as examples, the calculation process of the scale characteristic values of the flat beach river channel morphological evolution is described. Use the for statement in MATLAB to sequentially determine the equilibrium values A e 、H e 、B e of the flat beach cross-sectional area A, flat beach water depth H, and flat beach river width B at the river reach scale of river reach a. They are 24300, 17.4, and 1400 in turn. The attenuation coefficients α1, α2, α3 of the time adjustment process of the flat beach cross-sectional area A, flat beach water depth H, and flat beach river width B at the river reach scale are 0.06, 0.05, and 0.40 in turn. The equilibrium values A e 、H e 、B e of the flat beach cross-sectional area A, flat beach water depth H, and flat beach river width B at the river reach scale of river reach b are 19100, 14.7, and 1300 in turn. The attenuation coefficients α1, α2, α3 of the time adjustment process of the flat beach cross-sectional area, flat beach water depth, and flat beach river width are 0.25, 0.20, and 0.60 in turn. The calculation results are as shown in Figure 2 and Figure 3 shown.

[0084] Step 4: Analyze the adjustment mode of the flat beach river channel morphology of the target river reach.

[0085] Calculate the relative adjustment intensities A s 、H s 、B sTaking the values, using the plot function in MATLAB, the radar charts of the relative adjustment intensities A s , H s , B s of the floodplain cross-sectional area A, floodplain water depth H, and floodplain river width B at the reach scale for the typical reach a and the typical reach b are shown as Figure 4 and Figure 5 shown.

[0086] Based on the positive or negative cross-product values of the relative adjustment intensity vector of the floodplain water depth and the central vector, the positive or negative cross-product values of the relative adjustment intensity vector of the floodplain river width and the central vector, and the relative magnitude relationship between the modulus of the relative adjustment intensity vector of the floodplain water depth and the modulus of the relative adjustment intensity vector of the floodplain river width, the adjustment mode of the floodplain river channel morphology of the target reach is determined. The results show that the adjustment modes of the floodplain river channels of the typical reach a and the typical reach b are the downcutting type and the comprehensive type in sequence.

[0087] Step Five, predict the time scale of the adjustment of the floodplain river channel morphology of the target reach.

[0088] To better show the time variation law of the adjustment of the floodplain river channel morphology of the typical reach a and the typical reach b, based on the calculation results of the decay coefficients α1, α2, α3 of the time adjustment processes of the floodplain cross-sectional area, floodplain water depth, and floodplain river width obtained in Step Three, using the quantitative relationship α~T of the target reach (i.e., T = aα b ), the adjustment equilibrium times T1 = 2.5 / α1 of the floodplain cross-sectional area A, T2 = 2.5 / α2 of the floodplain water depth H, and T3 = 2.5 / α3 of the floodplain river width B at the reach scale of the target reach are calculated. The adjustment equilibrium times of the floodplain cross-sectional area A, floodplain water depth H, and floodplain river width B at the reach scale of this target reach are obtained. Among them, the values of T1, T2, and T3 of the typical reach a are 42, 50, and 6 respectively, and the values of T1, T2, and T3 of the typical reach b are 10, 13, and 4 respectively.

[0089] By comparing the magnitude relationships of the adjustment equilibrium times T1, T2, and T3 of the floodplain cross-sectional area A, floodplain water depth H, and floodplain river width B of the typical reach a and the typical reach b, the time scale characteristics of the evolution of the cross-sectional morphology of the target reach can be clarified.

[0090] It can be seen that the river channel evolution scale prediction method based on cross-section topography provided by the embodiments of the present application is based on long-sequence measured large cross-section data, with relatively low data acquisition difficulty, low cost, and high accuracy. Through the standardized processing of measured large cross-section observation data, the construction of a dataset of flat-bottom river channel morphological parameters for the target river reach, and the calculation of characteristic values of the morphological evolution of the flat-bottom river channel, it is possible to automatically calculate the adjustment mode and time scale of the flat-bottom river channel morphology of non-equilibrium alluvial rivers, with the advantages of accurate calculation, simple method, and fast operation. The embodiments of the present application are of great significance for quickly predicting the trend of river channel evolution and formulating corresponding treatment and protection plans, etc.

[0091] To better implement the river channel evolution scale prediction method based on cross-section topography in the embodiments of the present application, on the basis of the river channel evolution scale prediction method based on cross-section topography, the embodiments of the present application also provide a river channel evolution scale prediction device based on cross-section topography, as Figure 6 shown. The river channel evolution scale prediction device 600 based on cross-section topography includes: A first acquisition module 601, configured to acquire the observation data of the target river reach at multiple measurement times, as well as the operation years of the dam of the target river reach at the corresponding measurement times. The observation data includes the starting distances and riverbed elevations of multiple observation points at multiple cross-sections in the target river reach at the corresponding measurement times; A first determination module 602, configured to determine the flat-bottom river channel morphological parameters of each cross-section in the target river reach at the corresponding measurement time according to the observation data; A second determination module 603, configured to determine a first calculation formula for the flat-bottom river channel morphological parameters, where the first calculation formula includes the equilibrium value of the flat-bottom river channel morphological parameters at the reach scale and the attenuation coefficient of the flat-bottom river channel morphological parameters at the reach scale, both of which are calibrated based on the flat-bottom river channel morphological parameters of all cross-sections in the target river reach at all measurement times and the operation years of the dam; A third determination module 604, configured to determine the adjustment mode and time scale of the flat-bottom river channel morphology of the target river reach based on the flat-bottom river channel morphological parameters at the reach scale, the equilibrium value of the flat-bottom river channel morphological parameters at the reach scale, and the attenuation coefficient of the flat-bottom river channel morphological parameters at the reach scale, and obtain the prediction result of the flat-bottom river channel morphological evolution scale.

[0092] The embodiments of the present application also provide a computer device, which integrates any one of the river channel evolution scale prediction devices based on cross-section topography provided by the embodiments of the present application. As Figure 7 shown, it shows the structural schematic diagram of the computer device involved in the embodiments of the present application. Specifically: The computer device may include a processor 701 with one or more processing cores, a memory 702 with one or more computer-readable storage media, a power supply 703, an input unit 704, and other components. Those skilled in the art can understand,Figure 7 The computer device structure shown does not limit the construction of the computer device, which may include more or fewer components than shown, or combine certain components, or have different component arrangements. Among them: The processor 701 is the control center of the computer device, connecting various parts of the entire computer device through various interfaces and lines. By running or executing software programs and / or modules stored in the memory 702, and calling the data stored in the memory 702, it executes various functions of the computer device and processes data, thereby monitoring the computer device as a whole. Optionally, the processor 701 may include one or more processing cores; preferably, the processor 701 may integrate an application processor and a modem processor. Among them, the application processor mainly processes the operating system, user interface, application programs, etc., and the modem processor mainly processes wireless communication. It can be understood that the above-mentioned modem processor may not be integrated into the processor 701 either.

[0093] The memory 702 can be used to store software programs and modules. The processor 701 executes various functional applications and data processing by running the software programs and modules stored in the memory 702. The memory 702 mainly includes a program storage area and a data storage area. Among them, the program storage area can store the operating system, application programs required for at least one function (such as the sound playback function, image playback function, etc.), etc.; the data storage area can store the data created according to the use of the computer device, etc. In addition, the memory 702 can include high-speed random access memory, and can also include non-volatile memory, such as at least one magnetic disk storage device, flash memory device or other volatile solid-state storage devices. Correspondingly, the memory 702 can also include a memory controller to provide the processor 701 with access to the memory 702.

[0094] The computer device also includes a power supply 703 that powers each component. Preferably, the power supply 703 can be logically connected to the processor 701 through a power management system, so as to realize functions such as management of charging, discharging, and power consumption management through the power management system. The power supply 703 can also include any components such as one or more DC or AC power supplies, a recharge system, a power failure detection circuit, a power converter or inverter, and a power status indicator.

[0095] The computer device may also include an input unit 704, which can be used to receive input digital or character information, and generate keyboard, mouse, joystick, optical or trackball signal inputs related to user settings and function controls.

[0096] Although not shown, the computer device may further include a display unit and the like, which will not be elaborated here. Specifically, in this embodiment, the processor 701 in the computer device will load the executable files corresponding to the processes of one or more application programs into the memory 702 according to the following instructions, and the processor 701 will run the application programs stored in the memory 702 to implement various functions as follows: Obtain the observation data of the target river reach in multiple measurement times, as well as the operation years of the dam in the target river reach in the corresponding measurement times. The observation data includes the starting distances and riverbed elevations of multiple observation points at multiple cross-sections in the target river reach in the corresponding measurement times; according to the observation data, determine the flat-flood channel form parameters of each cross-section in the target river reach in the corresponding measurement times; determine the first calculation formula for the flat-flood channel form parameters, where the first calculation formula includes the equilibrium value of the flat-flood channel form parameters at the river reach scale and the attenuation coefficient of the flat-flood channel form parameters at the river reach scale, both of which are calibrated based on the flat-flood channel form parameters of all cross-sections in the target river reach in all measurement times and the operation years of the dam; based on the flat-flood channel form parameters at the river reach scale, the equilibrium value of the flat-flood channel form parameters at the river reach scale, and the attenuation coefficient of the flat-flood channel form parameters at the river reach scale of the target river reach, determine the flat-flood channel form adjustment mode and time scale of the target river reach, and obtain the prediction result of the flat-flood channel form evolution scale.

[0097] Those of ordinary skill in the art can understand that all or part of the steps in the various methods of the above embodiments can be completed by instructions, or by controlling related hardware through instructions. The instructions can be stored in a computer-readable storage medium and loaded and executed by a processor.

[0098] For this reason, an embodiment of the present application provides a computer-readable storage medium, which may include: read-only memory (ROM, Read Only Memory), random access memory (RAM, Random Access Memory), a magnetic disk or an optical disc, etc. A computer program is stored thereon, and the computer program is loaded by a processor to execute the steps in any one of the methods for predicting the evolution scale of a river channel based on cross-section topography provided by the embodiments of the present application. For example, when the computer program is loaded by a processor, it can execute the following steps: Obtain the observation data of the target river reach at multiple measurement times, as well as the operation years of the dam of the target river reach at the corresponding measurement times. The observation data includes the starting distances and riverbed elevations of multiple observation points at multiple cross-sections in the target river reach at the corresponding measurement times. According to the observation data, determine the flat flood channel morphological parameters of each cross-section in the target river reach at the corresponding measurement times. Determine the first calculation formula for the flat flood channel morphological parameters, where the first calculation formula includes the equilibrium value of the flat flood channel morphological parameters at the river reach scale and the attenuation coefficient of the flat flood channel morphological parameters at the river reach scale, both of which are calibrated based on the flat flood channel morphological parameters of all cross-sections in the target river reach at all measurement times and the operation years of the dam. Based on the flat flood channel morphological parameters at the river reach scale, the equilibrium value of the flat flood channel morphological parameters at the river reach scale, and the attenuation coefficient of the flat flood channel morphological parameters at the river reach scale of the target river reach, determine the flat flood channel morphological adjustment mode and time scale of the target river reach, and obtain the prediction result of the flat flood channel morphological evolution scale.

[0099] An embodiment of the present application further provides a computer program product or a computer program. The computer program product or the computer program includes computer instructions, and the computer instructions are stored in a computer-readable storage medium. The processor of the electronic device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions to enable the electronic device to execute to implement the method for predicting the river channel evolution scale based on cross-section topography as described in any one of the above, for example: Obtain the observation data of the target river reach at multiple measurement times, as well as the operation years of the dam of the target river reach at the corresponding measurement times. The observation data includes the starting distances and riverbed elevations of multiple observation points at multiple cross-sections in the target river reach at the corresponding measurement times. According to the observation data, determine the flat flood channel morphological parameters of each cross-section in the target river reach at the corresponding measurement times. Determine the first calculation formula for the flat flood channel morphological parameters, where the first calculation formula includes the equilibrium value of the flat flood channel morphological parameters at the river reach scale and the attenuation coefficient of the flat flood channel morphological parameters at the river reach scale, both of which are calibrated based on the flat flood channel morphological parameters of all cross-sections in the target river reach at all measurement times and the operation years of the dam. Based on the flat flood channel morphological parameters at the river reach scale, the equilibrium value of the flat flood channel morphological parameters at the river reach scale, and the attenuation coefficient of the flat flood channel morphological parameters at the river reach scale of the target river reach, determine the flat flood channel morphological adjustment mode and time scale of the target river reach, and obtain the prediction result of the flat flood channel morphological evolution scale.

[0100] In the above embodiments, the descriptions of the various embodiments have their own focuses. For the parts not detailed in a certain embodiment, reference may be made to the detailed descriptions of other embodiments above, and details will not be repeated here.

[0101] In specific implementation, each of the above units or structures can be implemented as an independent entity, or can be arbitrarily combined and implemented as the same or several entities. For the specific implementation of each of the above units or structures, reference can be made to the foregoing method embodiments, which will not be elaborated herein.

[0102] For the specific implementation of each of the above operations, reference can be made to the foregoing embodiments, which will not be elaborated herein.

[0103] The foregoing has introduced in detail a method for predicting the scale of river channel evolution based on cross-sectional topography and related devices provided by the embodiments of the present application. Specific examples are used herein to elaborate on the principle and implementation manner of the present application. The description of the above embodiments is only used to help understand the method and its core idea of the present application; at the same time, for those skilled in the art, according to the idea of the present application, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present application.

Claims

1. A method for predicting the scale of river channel evolution based on cross-section topography, characterized in that The method includes: Obtaining the observation data of the target river reach at multiple measurement times, as well as the operation years of the dam of the target river reach at the corresponding measurement times, wherein the observation data includes the starting distances and riverbed elevations of multiple observation points at multiple cross-sections in the target river reach at the corresponding measurement times; Determining the flat beach river channel morphological parameters of each cross-section in the target river reach according to the observation data; Determining a first calculation formula for the flat beach river channel morphological parameters, wherein the first calculation formula includes the equilibrium value of the flat beach river channel morphological parameters at the river reach scale and the attenuation coefficient of the flat beach river channel morphological parameters at the river reach scale, both of which are calibrated based on the flat beach river channel morphological parameters of all cross-sections in the target river reach at all measurement times and the operation years of the dam; Based on the flat beach river channel morphological parameters at the river reach scale, the equilibrium value of the flat beach river channel morphological parameters at the river reach scale, and the attenuation coefficient of the flat beach river channel morphological parameters at the river reach scale of the target river reach, determining the flat beach river channel morphological adjustment mode and time scale of the target river reach, and obtaining the prediction result of the flat beach river channel morphological evolution scale.

2. The method for predicting the scale of river channel evolution based on cross-sectional topography according to claim 1, wherein The flat beach river channel morphological parameters at the river reach scale include the flat beach cross-section area, flat beach water depth, and flat beach river width at the river reach scale, and the equilibrium value of the flat beach river channel morphological parameters at the river reach scale includes the equilibrium value of the flat beach cross-section area, the equilibrium value of the flat beach water depth, and the equilibrium value of the flat beach river width; The flat beach river channel morphological adjustment mode of the target river reach is determined through the following steps: According to the equilibrium value of the flat beach river channel morphological parameters at the river reach scale and the initial value of the flat beach river channel morphological parameters at the river reach scale, determining the relative adjustment intensity of the flat beach river channel morphological parameters at the river reach scale, and the relative adjustment intensity includes the relative adjustment intensity of the flat beach cross-section area, the relative adjustment intensity of the flat beach water depth, and the relative adjustment intensity of the flat beach river width; Based on the relative adjustment intensity of the flat beach cross-section area, the relative adjustment intensity of the flat beach water depth, and the relative adjustment intensity of the flat beach river width, determining the flat beach river channel morphological adjustment mode.

3. The method for predicting the scale of river channel evolution based on cross-sectional topography according to claim 2, wherein The determining the flat beach river channel morphological adjustment mode based on the relative adjustment intensity of the flat beach cross-section area, the relative adjustment intensity of the flat beach water depth, and the relative adjustment intensity of the flat beach river width includes: Determining a radar chart among the relative adjustment intensity of the flat beach cross-section area, the relative adjustment intensity of the flat beach water depth, and the relative adjustment intensity of the flat beach river width; Coordinatizing the vertices in the radar chart to respectively determine the relative adjustment intensity coordinate point of the flat beach water depth, the relative adjustment intensity coordinate point of the flat beach river width, and the vector between the center point of the radar chart and the coordinate origin; Based on the relative adjustment intensity coordinate point of the flat beach water depth, the relative adjustment intensity coordinate point of the flat beach river width, and the vector between the center point of the radar chart and the coordinate origin, determining the flat beach river channel morphological adjustment mode, and the flat beach river channel morphological adjustment mode includes at least one of downcutting adjustment, widening adjustment, and comprehensive adjustment.

4. The method for predicting the scale of river channel evolution based on cross-sectional topography according to claim 3, characterized in that, The determining the flat beach river channel morphological adjustment mode based on the relative adjustment intensity coordinate point of the flat beach water depth, the relative adjustment intensity coordinate point of the flat beach river width, and the vector between the center point of the radar chart and the coordinate origin includes: Determine the first cross product value between the vector from the relative adjustment intensity coordinate point of the thalweg depth to the origin of coordinates and the vector from the center point of the radar chart to the origin of coordinates; Determine the second cross product value between the vector from the relative adjustment intensity coordinate point of the thalweg width to the origin of coordinates and the vector from the center point of the radar chart to the origin of coordinates; Determine the first ratio between the magnitude of the vector from the relative adjustment intensity coordinate point of the thalweg depth to the origin of coordinates and the magnitude of the vector from the relative adjustment intensity coordinate point of the thalweg width to the origin of coordinates; Based on the positive or negative of the first cross product value and the second cross product value, and the magnitude of the first ratio, determine the adjustment mode of the thalweg channel form.

5. The method for predicting the scale of river channel evolution based on cross-sectional topography according to any one of claims 1 to 4, characterized in that, The adjustment time scale of the thalweg channel form of the target river reach is determined through the following steps: For the target river reach, determine the quantitative relationship between the attenuation coefficient of the thalweg channel form parameters at the river reach scale and the adjustment equilibrium time of the thalweg channel form parameters at the river reach scale; Input the attenuation coefficient of the thalweg channel form parameters at the river reach scale into the quantitative relationship to determine the adjustment equilibrium time of the thalweg channel form parameters at the river reach scale. The adjustment time scale of the thalweg channel form includes the adjustment equilibrium time of the thalweg channel form parameters at the river reach scale, and the adjustment equilibrium time of the thalweg channel form parameters at the river reach scale includes the adjustment equilibrium time of the cross-sectional area of the thalweg, the thalweg depth, and the thalweg width at the river reach scale.

6. The method for predicting the scale of river channel evolution based on cross-section topography according to claim 5, wherein, For the target river reach, determining the quantitative relationship between the attenuation coefficient of the thalweg channel form parameters at the river reach scale and the adjustment equilibrium time of the thalweg channel form parameters at the river reach scale includes: For each cross section in the target river reach, determine the second calculation formula of the thalweg channel form parameters, where the second calculation formula includes the equilibrium value of the thalweg channel form parameters at the cross-sectional scale and the attenuation coefficient of the thalweg channel form parameters at the cross-sectional scale, both of which are calibrated based on the thalweg channel form parameters at the corresponding cross section in the target river reach at the cross-sectional scale and the operation years of the dam; For each cross section in the target river reach, determine the time corresponding to the adjustment amount of the thalweg channel form parameters at the corresponding cross section in the target river reach reaching the target adjustment amount, and use it as the preliminary estimated adjustment equilibrium time. The target adjustment amount is determined based on the difference between the equilibrium value of the thalweg channel form parameters at the corresponding cross section in the target river reach at the cross-sectional scale and the initial value of the thalweg channel form parameters at the corresponding cross section in the target river reach; According to the attenuation coefficient of the thalweg channel form parameters at the cross-sectional scale and the preliminary estimated adjustment equilibrium time of all cross sections in the target river reach, determine the quantitative relationship.

7. The method for predicting the scale of river channel evolution based on cross-sectional topography according to claim 6, wherein, According to the attenuation coefficient of the thalweg channel form parameters at the cross-sectional scale and the preliminary estimated adjustment equilibrium time of all cross sections in the target river reach, determining the quantitative relationship includes: Generate a scatter plot of the attenuation coefficient of the thalweg channel form parameters at the cross-sectional scale and the preliminary estimated adjustment equilibrium time of all cross sections in the target river reach; Determine the upper and lower envelope lines in the scatter plot; Take the average value of the data of the upper and lower envelope lines, and then perform curve fitting to obtain the quantitative relationship.

8. The method for predicting the scale of river channel evolution based on cross-sectional topography according to claim 1, wherein, The first calculation formula is determined through the following formula: Among them, is the value of the flat beach channel form parameter at (x, t), where x is the mileage from the dam of the corresponding cross-section in the target river reach, t is the operation years of the dam, and Y e is the corresponding equilibrium value of the flat beach channel form parameter, Φ(x, t) is the flat beach channel form boundary function, and Φ e is the equilibrium value of the flat beach channel form boundary function, e is the natural constant, α is the attenuation coefficient of the corresponding flat beach channel form parameter, v is the propagation rate of the change of the corresponding flat beach channel form parameter in space, and t0 is the initial value of the operation years of the dam.

9. A computer device, characterized in that, The computer device includes: One or more processors; A memory; and one or more application programs, wherein the one or more application programs are stored in the memory and configured to be executed by the processor to implement the steps in the cross-section terrain-based river evolution scale prediction method according to any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that, A computer program is stored thereon, and the computer program is loaded by a processor to execute the steps in the cross-section terrain-based river evolution scale prediction method according to any one of claims 1 to 8.

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