Methods, apparatus, equipment, and storage media for mapping river inundation based on cross-sectional water levels.

Abstract

This invention discloses a method for mapping river inundation based on cross-sectional water levels, comprising: acquiring cross-sectional data of each river section, riverbed roughness, hourly flow rate at the upper boundary, and water level at the lower boundary, and determining the cross-sectional water level and the river section water level line; calculating the first inundation distance and multiple second inundation distances from the first cross-sectional riverbank point to the center section of the target river for each river section; determining the coordinates of a first side riverbank point adjacent to the first cross-sectional riverbank point based on the third coordinate of the riverbank point closest to the river section, the second inundation distance, and the first coordinate of the first cross-sectional riverbank point; and the coordinates of other first side riverbank points and second side riverbank points; drawing the first bank based on the coordinates of the first side riverbank point, and drawing the second bank based on the coordinates of the second side riverbank point. This application can accurately determine the inundation range, predict flood-prone areas in advance, assess flood inundation losses, formulate flood prevention plans, and reduce threats to life and property safety.

Description

Technical Field

[0001] This invention relates to the field of river inundation range mapping technology, and in particular to a method, apparatus, equipment and storage medium for river inundation mapping based on cross-sectional water level. Background Technology

[0002] Floods, as highly destructive natural disasters, often cause enormous loss of life and property to human societies. They can destroy houses, inundate farmland, damage transportation and infrastructure, severely disrupt normal social order, and even threaten human survival. Therefore, efficiently simulating flood processes and quickly and accurately determining the inundation area during floods is of paramount importance for flood impact and loss assessment, and for flood prevention and disaster reduction decision-making.

[0003] Currently, one-dimensional hydrodynamic models are widely used in rapid flood simulation. Based on the principles of mass and momentum conservation, one-dimensional hydrodynamic models simplify water flow into one-dimensional flow and quickly simulate the changes in water level and flow rate over time at key cross-sections by solving the Saint-Venant equations, providing fundamental data for subsequent flood analysis.

[0004] In real-world flood scenarios, simply understanding the inundation extent of a river cross-section is far from sufficient. The impact of flood disasters extends beyond the cross-section itself, encompassing vast areas between cross-sections. This lack of effective understanding of the inundation extent at and between cross-sections prevents us from comprehensively and accurately assessing the degree of flood impact on different areas during flood impact and loss assessments. Consequently, we are unable to effectively protect people's lives and property or rationally plan flood control facilities. Summary of the Invention

[0005] Therefore, it is necessary to propose a method, apparatus, equipment, and storage medium for mapping river inundation based on cross-sectional water levels to address the above-mentioned problems.

[0006] A method for mapping river inundation based on cross-sectional water levels, wherein the first bank of the river is composed of several first side bank points, and the second bank of the river is composed of several second side bank points, wherein the first side bank points and the second side bank points are located on opposite sides of the river centerline, the method comprising:

[0007] Load Tianditu satellite imagery into the ArcGIS geographic information system, identify the target river channel in the Tianditu satellite imagery, and determine the centerline of the target river channel.

[0008] Define multiple river cross sections of the target river channel, and obtain the cross section data, riverbed roughness, hourly flow rate at the upper boundary, and water level at the lower boundary for each river cross section; the cross section data includes: river cross section line and river cross section curve;

[0009] The cross-sectional water level is determined based on the river channel cross-sectional curve, the riverbed roughness, the hourly flow rate at the upper boundary, and the water level at the lower boundary.

[0010] The river channel cross-section water level line is determined based on the cross-sectional water level.

[0011] Obtain the first coordinates of the first cross-section riverbank point and the second coordinates of the second cross-section riverbank point. The two intersection points of the river cross-section water level line and the river cross-section curve are respectively the first cross-section riverbank point and the second cross-section riverbank point of the river cross-section. The first cross-section riverbank point belongs to the first side riverbank point, and the second cross-section riverbank point belongs to the second side riverbank point.

[0012] The centerline between two adjacent river sections is divided into multiple river center segments at equal intervals. The connection point between adjacent river center segments is called a river point, and the third coordinate of each river point is determined.

[0013] Calculate the first inundation distance from the first cross-section riverbank point of each river channel to the target river channel center section in sequence, where the target river channel center section is the line connecting the two river channel points closest to the river channel cross-section.

[0014] Multiple second inundation distances are determined based on the two first inundation distances corresponding to two adjacent river cross sections, wherein the second inundation distance is the vertical distance from each first side bank point to the corresponding nearest river center segment;

[0015] Based on the third coordinate of the river point closest to the river cross-section, the second inundation distance, and the first coordinate of the first cross-section riverbank point, determine the coordinates of the first side riverbank point adjacent to the first cross-section riverbank point; and repeat this step to calculate the coordinates of other first side riverbank points and the coordinates of second side riverbank points.

[0016] Draw the first bank based on the coordinates of each first bank point, and draw the second bank based on the coordinates of each second bank point.

[0017] In one embodiment, determining the cross-sectional water level based on the river channel cross-sectional curve, the riverbed roughness, the hourly flow rate at the upper boundary, and the water level at the lower boundary includes:

[0018] The river channel cross-sectional curve and the riverbed roughness are used as inputs to a one-dimensional hydrodynamic model. The hourly flow rate at the upper boundary is used as the upper boundary condition of the one-dimensional hydrodynamic model, and the water level at the lower boundary is used as the lower boundary condition of the one-dimensional hydrodynamic model, so that the one-dimensional hydrodynamic model outputs the cross-sectional water level.

[0019] In one embodiment, determining multiple second inundation distances based on two first inundation distances corresponding to two adjacent river cross-sections includes:

[0020] Multiple second inundation distances are determined by calculating the difference between the two first inundation distances corresponding to two adjacent river sections.

[0021] In one embodiment, the first flooding distance is calculated as follows:

[0022]

[0023] Where D1 is the first inundation distance, and the coordinates of the first cross-section riverbank point S1 are (x... s ,y s The coordinates of the two river points closest to the river cross-section are P1(x1,y1) and P2(x2,y2).

[0024] In one embodiment, the second flooding distance is calculated as follows:

[0025]

[0026] Among them, D i For the second flooding distance, D1 and D n These are the two first inundation distances corresponding to two adjacent river cross sections, where i is the i-th riverbank point and n is the n-th riverbank point.

[0027] A river inundation mapping device based on cross-sectional water level, comprising:

[0028] The loading module is used to load Tianditu satellite imagery into the ArcGIS geographic information system, determine the target river channel in the Tianditu satellite imagery, and determine the centerline of the target river channel.

[0029] The first acquisition module is used to define multiple river cross sections of the target river channel and acquire the cross section data, riverbed roughness, hourly flow rate at the upper boundary, and water level at the lower boundary for each river cross section; the cross section data includes: river cross section line and river cross section curve;

[0030] The first determining module is used to determine the cross-sectional water level based on the river channel cross-sectional curve, the riverbed roughness, the hourly flow rate at the upper boundary, and the water level at the lower boundary.

[0031] The second determining module is used to determine the river channel cross-section water level line based on the cross-section water level.

[0032] The second acquisition module is used to acquire the first coordinates of the first cross-section riverbank point and the second coordinates of the second cross-section riverbank point. The two intersection points of the river cross-section water level line and the river cross-section curve are respectively the first cross-section riverbank point and the second cross-section riverbank point of the river cross-section. The first cross-section riverbank point belongs to the first side riverbank point, and the second cross-section riverbank point belongs to the second side riverbank point.

[0033] The third determining module is used to divide the centerline of the river between two adjacent river sections into multiple river center segments at equal intervals, the connection point of the adjacent river center segments is the river point, and the third coordinate of each river point is determined.

[0034] The calculation module is used to sequentially calculate the first inundation distance from the first cross-section riverbank point of each river section to the target river center section, wherein the target river center section is the line connecting the two river points closest to the river section.

[0035] The fourth determining module is used to determine multiple second inundation distances based on the two first inundation distances corresponding to two adjacent river cross sections, wherein the second inundation distance is the vertical distance from each first side riverbank point to the corresponding nearest river center segment;

[0036] The fifth determining module is used to determine the coordinates of a first side riverbank point adjacent to the first cross-section riverbank point based on the third coordinate of the river point closest to the river cross-section, the second inundation distance, and the first coordinate of the first cross-section riverbank point; and repeat this step to calculate the coordinates of other first side riverbank points and the coordinates of second side riverbank points;

[0037] The drawing module is used to draw the first bank based on the coordinates of each first riverbank point and the second bank based on the coordinates of each second riverbank point.

[0038] In one embodiment,

[0039] The second determining module is further configured to use the river channel cross-sectional curve and the riverbed roughness as inputs to the one-dimensional hydrodynamic model, use the hourly flow rate of the upper boundary as the upper boundary condition of the one-dimensional hydrodynamic model, and use the water level of the lower boundary as the lower boundary condition of the one-dimensional hydrodynamic model, so that the one-dimensional hydrodynamic model outputs the cross-sectional water level.

[0040] In one embodiment,

[0041] The fourth determining module is also used to determine multiple second inundation distances by calculating the difference between the two first inundation distances corresponding to two adjacent river sections.

[0042] A computer device includes a memory and a processor, the memory storing a computer program that, when executed by the processor, causes the processor to perform the following steps:

[0043] Load Tianditu satellite imagery into the ArcGIS geographic information system, identify the target river channel in the Tianditu satellite imagery, and determine the centerline of the target river channel.

[0044] Define multiple river cross sections of the target river channel, and obtain the cross section data, riverbed roughness, hourly flow rate at the upper boundary, and water level at the lower boundary for each river cross section; the cross section data includes: river cross section line and river cross section curve;

[0045] The cross-sectional water level is determined based on the river channel cross-sectional curve, the riverbed roughness, the hourly flow rate at the upper boundary, and the water level at the lower boundary.

[0046] The river channel cross-section water level line is determined based on the cross-sectional water level.

[0047] Obtain the first coordinates of the first cross-section riverbank point and the second coordinates of the second cross-section riverbank point. The two intersection points of the river cross-section water level line and the river cross-section curve are respectively the first cross-section riverbank point and the second cross-section riverbank point of the river cross-section. The first cross-section riverbank point belongs to the first side riverbank point, and the second cross-section riverbank point belongs to the second side riverbank point.

[0048] The centerline between two adjacent river sections is divided into multiple river center segments at equal intervals. The connection point between adjacent river center segments is called a river point, and the third coordinate of each river point is determined.

[0049] Calculate the first inundation distance from the first cross-section riverbank point of each river channel to the target river channel center section in sequence, where the target river channel center section is the line connecting the two river channel points closest to the river channel cross-section.

[0050] Multiple second inundation distances are determined based on the two first inundation distances corresponding to two adjacent river cross sections, wherein the second inundation distance is the vertical distance from each first side bank point to the corresponding nearest river center segment;

[0051] Based on the third coordinate of the river point closest to the river cross-section, the second inundation distance, and the first coordinate of the first cross-section riverbank point, determine the coordinates of the first side riverbank point adjacent to the first cross-section riverbank point; and repeat this step to calculate the coordinates of other first side riverbank points and the coordinates of second side riverbank points.

[0052] A first bank is drawn based on the coordinates of each first riverbank point, and a second bank is drawn based on the coordinates of each second riverbank point. A computer-readable storage medium stores a computer program, which, when executed by a processor, causes the processor to perform the following steps:

[0053] Load Tianditu satellite imagery into the ArcGIS geographic information system, identify the target river channel in the Tianditu satellite imagery, and determine the centerline of the target river channel.

[0054] Define multiple river cross sections of the target river channel, and obtain the cross section data, riverbed roughness, hourly flow rate at the upper boundary, and water level at the lower boundary for each river cross section; the cross section data includes: river cross section line and river cross section curve;

[0055] The cross-sectional water level is determined based on the river channel cross-sectional curve, the riverbed roughness, the hourly flow rate at the upper boundary, and the water level at the lower boundary.

[0056] The river channel cross-section water level line is determined based on the cross-sectional water level.

[0057] Obtain the first coordinates of the first cross-section riverbank point and the second coordinates of the second cross-section riverbank point. The two intersection points of the river cross-section water level line and the river cross-section curve are respectively the first cross-section riverbank point and the second cross-section riverbank point of the river cross-section. The first cross-section riverbank point belongs to the first side riverbank point, and the second cross-section riverbank point belongs to the second side riverbank point.

[0058] The centerline between two adjacent river sections is divided into multiple river center segments at equal intervals. The connection point between adjacent river center segments is called a river point, and the third coordinate of each river point is determined.

[0059] Calculate the first inundation distance from the first cross-section riverbank point of each river channel to the target river channel center section in sequence, where the target river channel center section is the line connecting the two river channel points closest to the river channel cross-section.

[0060] Multiple second inundation distances are determined based on the two first inundation distances corresponding to two adjacent river cross sections, wherein the second inundation distance is the vertical distance from each first side bank point to the corresponding nearest river center segment;

[0061] Based on the third coordinate of the river point closest to the river cross-section, the second inundation distance, and the first coordinate of the first cross-section riverbank point, determine the coordinates of the first side riverbank point adjacent to the first cross-section riverbank point; and repeat this step to calculate the coordinates of other first side riverbank points and the coordinates of second side riverbank points.

[0062] Draw the first bank based on the coordinates of each first bank point, and draw the second bank based on the coordinates of each second bank point.

[0063] The method for drawing the inundation range of a river channel provided in this application can generate a two-dimensional inundation range consistent with the river channel trend based on the cross-sectional water level calculated by a one-dimensional hydrodynamic model. This helps relevant departments to predict areas that may be inundated by floods in advance, assess flood inundation losses, and formulate more scientific and reasonable flood control plans, thereby reducing the threat of floods to people's lives and property. Attached Figure Description

[0064] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0065] in:

[0066] Figure 1 This is an application environment diagram of a river inundation drawing method based on cross-sectional water level in one embodiment;

[0067] Figure 2 This is a flowchart of a method for drawing river inundation based on cross-sectional water level in one embodiment;

[0068] Figure 3 This is a schematic diagram of the cross-sectional water level in one embodiment;

[0069] Figure 4 This is a schematic diagram of the river channel point and riverbank point on the river channel in one embodiment;

[0070] Figure 5 This is a rendering of the inundation area of ​​a river channel in one embodiment;

[0071] Figure 6 This is a structural block diagram of a river inundation mapping device based on cross-sectional water level in one embodiment;

[0072] Figure 7 This is a structural block diagram of a computer device in one embodiment. Detailed Implementation

[0073] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0074] Figure 1 This is an application environment diagram of a river inundation mapping method based on cross-sectional water level in one embodiment. (Refer to...) Figure 1This method for mapping river inundation based on cross-sectional water levels is applied to a river inundation mapping system based on cross-sectional water levels. The system includes a terminal 110 and a server 120. The terminal 110 and server 120 are connected via a network. The terminal 110 can be a desktop terminal or a mobile terminal; the mobile terminal can be at least one of a mobile phone, tablet, or laptop. The server 120 can be a standalone server or a server cluster consisting of multiple servers. Terminal 110 is used to: load Tianditu satellite imagery into the ArcGIS geographic information system, determine the target river channel in the Tianditu satellite imagery, and determine the centerline of the target river channel; define multiple river cross-sections of the target river channel, and acquire cross-sectional data, riverbed roughness, hourly flow rate at the upper boundary, and water level at the lower boundary for each river cross-section; the cross-sectional data includes: river cross-sectional line and river cross-sectional curve; determine the cross-sectional water level based on the river cross-sectional curve, the riverbed roughness, hourly flow rate at the upper boundary, and water level at the lower boundary; determine the river cross-sectional water level line based on the cross-sectional water level; server 120 is used to acquire the first coordinates of the first cross-sectional riverbank point and the second cross-sectional riverbank point, wherein the two intersections of the river cross-sectional water level line and the river cross-sectional curve are respectively the first cross-sectional riverbank point and the second cross-sectional riverbank point of the river cross-section, the first cross-sectional riverbank point belongs to the first side riverbank point, and the second cross-sectional riverbank point belongs to the second side riverbank point; and connect two adjacent river... The river channel centerline between cross-sections is divided into multiple river channel center segments at equal intervals. The connection point of adjacent river channel center segments is a river point, and the third coordinate of each river point is determined. The first inundation distance from the first cross-section riverbank point to the target river channel center segment is calculated sequentially. The target river channel center segment is the line connecting the two river points closest to the river channel cross-section. Multiple second inundation distances are determined based on the two first inundation distances corresponding to two adjacent river channels. The second inundation distance is the vertical distance from each first side riverbank point to the corresponding nearest river channel center segment. The coordinates of the first side riverbank point adjacent to the first cross-section riverbank point are determined based on the third coordinate of the river point closest to the river channel cross-section, the second inundation distance, and the first coordinate of the first cross-section riverbank point. This step is repeated to calculate the coordinates of other first side riverbank points and second side riverbank points. The first bank is drawn based on the coordinates of each first side riverbank point, and the second bank is drawn based on the coordinates of each second side riverbank point.

[0075] Floods, as highly destructive natural disasters, often cause enormous loss of life and property to human societies. They can destroy houses, inundate farmland, damage transportation and infrastructure, severely disrupt normal social order, and even threaten human survival. How to efficiently simulate flood processes and quickly and accurately grasp the inundation range during floods is of paramount importance for flood impact and loss assessment, and flood prevention and mitigation decision-making. Currently, one-dimensional hydrodynamic models are widely used in rapid flood simulation. Based on the principles of mass and momentum conservation, one-dimensional hydrodynamic models simplify water flow into one-dimensional flow and quickly simulate the changes in water level and flow rate at key cross-sections over time by solving the Saint-Venant equations, providing fundamental data for subsequent flood analysis. In actual flood scenarios, simply knowing the inundation range of a river cross-section is far from sufficient. The impact of flood disasters is not limited to the cross-section but also involves a vast area between cross-sections. Due to the lack of effective control over the inundation range of cross-sections and between them, we cannot comprehensively and accurately assess the degree of impact of floods on different areas when conducting flood impact and loss assessments. The system cannot effectively protect people's lives and property, nor can it rationally plan flood control facilities. To address these technical problems, this application provides a method for mapping river inundation based on cross-sectional water levels. The first bank of the river is composed of several first side bank points, and the second bank is composed of several second side bank points. The first and second side bank points are located on opposite sides of the river's centerline. Figure 2 As shown, the method includes:

[0076] S10: Load the Tianditu satellite imagery into the ArcGIS geographic information system, determine the target river channel in the Tianditu satellite imagery, and determine the centerline of the target river channel;

[0077] S20: Define multiple river cross-sections of the target river channel, and obtain the cross-sectional data of each river cross-section, the riverbed roughness, the hourly flow rate at the upper boundary, and the water level at the lower boundary; the cross-sectional data includes: river cross-section lines and river cross-section curves;

[0078] S30: Determine the cross-sectional water level based on the river channel cross-section curve, the riverbed roughness, the hourly flow rate at the upper boundary, and the water level at the lower boundary;

[0079] S40: Determine the river channel cross-section water level line based on the cross-section water level;

[0080] S50: Obtain the first coordinates of the first cross-section riverbank point S1 (i.e., the left riverbank point S1) and the second coordinates of the second cross-section riverbank point S2. The two intersections of the river cross-section water level line and the river cross-section curve are the first cross-section riverbank point S1 and the second cross-section riverbank point S2 of the river cross-section, respectively. The first cross-section riverbank point S1 belongs to the first side riverbank point, and the second cross-section riverbank point S2 belongs to the second side riverbank point.

[0081] S60: Divide the centerline of the river between two adjacent river sections into multiple river center segments at equal intervals. The connection point of the adjacent river center segments is the river point, and determine the third coordinate of each river point P.

[0082] S70: Calculate the first inundation distance D1 from the first cross-section riverbank point S1 of each river channel to the target river center section in sequence. The target river center section is the line connecting the two river points closest to the river channel cross-section.

[0083] S80: Determine multiple second inundation distances D based on the two first inundation distances D1 corresponding to two adjacent river cross sections. i The second flooding distance D i The vertical distance from each point on the first side of the riverbank to the corresponding nearest center segment of the river channel;

[0084] S90: Based on the third coordinate of the river point closest to the river cross-section and the second inundation distance D i The first coordinate of the first cross-section riverbank point S1 determines the coordinate of the first side riverbank point adjacent to the first cross-section riverbank point S1; and this step is repeated to calculate the coordinates of other first side riverbank points and the coordinates of second side riverbank points.

[0085] S100: Draw the first bank based on the coordinates of each first side riverbank point, and draw the second bank based on the coordinates of each second side riverbank point.

[0086] The method for drawing the inundation range of a river channel provided in this application can generate a two-dimensional inundation range consistent with the river channel trend based on the cross-sectional water level calculated by a one-dimensional hydrodynamic model. This helps relevant departments to predict areas that may be inundated by floods in advance, assess flood inundation losses, and formulate more scientific and reasonable flood control plans, thereby reducing the threat of floods to people's lives and property.

[0087] In one embodiment, determining the cross-sectional water level based on the river cross-section curve, the riverbed roughness, the hourly flow rate at the upper boundary, and the water level at the lower boundary in step S30 includes:

[0088] S301: The river channel cross-sectional curve and the riverbed roughness are used as inputs to the one-dimensional hydrodynamic model. The hourly flow rate at the upper boundary is used as the upper boundary condition of the one-dimensional hydrodynamic model (HEC-RAS model), and the water level at the lower boundary is used as the lower boundary condition of the one-dimensional hydrodynamic model (HEC-RAS model), so that the one-dimensional hydrodynamic model (HEC-RAS model) outputs the cross-sectional water level.

[0089] In one embodiment, for step S80, determining multiple second inundation distances D based on the two first inundation distances D1 corresponding to two adjacent river cross-sections... i include:

[0090] S801: By calculating the difference between the two first inundation distances D1 corresponding to two adjacent river cross sections, multiple second inundation distances D are determined. i .

[0091] In one embodiment, the calculation method for the first flooding distance D1 in step S70 is as follows:

[0092]

[0093] Where D1 is the first inundation distance, and the coordinates of the first cross-section riverbank point S1 are (x... s ,y s The coordinates of the two river points closest to the river cross-section are P1(x1,y1) and P2(x2,y2), respectively.

[0094] In one embodiment, for the second flooding distance D in step S801 i The calculation method is as follows:

[0095]

[0096] Among them, D i For the second flooding distance, D1 and D n These are the two first inundation distances corresponding to two adjacent river cross sections, where i is the i-th riverbank point and n is the n-th riverbank point.

[0097] Specifically, we will illustrate the solution of this application with a real-world example:

[0098] At a specific moment, in a geographic information system, the river cross-section water level line is determined based on the cross-sectional water level. The two intersection points of the river cross-section water level line and the river cross-section curve are respectively the first cross-section riverbank point S1 and the second cross-section riverbank point S2 of the river cross-section. The first cross-section riverbank point S1 belongs to the first side riverbank point, and the second cross-section riverbank point S2 belongs to the second side riverbank point. The first coordinate of the first cross-section riverbank point S1 and the second coordinate of the second cross-section riverbank point S2 are determined. The first cross-section riverbank point S1 and the second cross-section riverbank point S2 are on both sides of the river centerline. Figure 3 As shown.

[0099] The river channel centerline between two adjacent river sections is divided into multiple river channel center segments at equal intervals. The connection points between adjacent river channel center segments are called river channel points, and the coordinates of each river channel point are determined, such as... Figure 4 As shown, the river points are designated P1 to P7. Connecting these river points sequentially should reflect the meandering shape of the river.

[0100] Calculate the first inundation distance D1 from the first cross-section riverbank point S1 to the center section of the river for each river cross-section in sequence. The target center section of the river is the line connecting the two river points closest to the river cross-section.

[0101] from Figure 4 As can be seen from this, there is a first cross-section riverbank point S1 on one of the river channel cross-sections S1S2, which is located to the left of the river channel centerline. ， The distance between any two river points on the river centerline is equal. The perpendicular distance from the line connecting the first cross-section riverbank point S1 to the line connecting the first two river points P1 and P2 is the first inundation distance D1. Calculate the perpendicular distance D7 between the riverbank point E1 on the left side of the other river cross-section E1E2 and the line connecting the last two river points P6 and P7. Based on the first inundation distance D1 and the perpendicular distance D7, interpolate the inundation distances of each river point between the two cross-sections to calculate the left-side inundation distance of each river point.

[0102] Riverbank point S1(x s ,y s The formula for calculating the perpendicular distance from the line connecting river points P1(x1,y1) and P2(x2,y2) is as follows:

[0103]

[0104] Riverbank point E1(x e ,y e The formula for calculating the perpendicular distance from the line connecting river points P6(x3,y3) and P7(x4,y4) is as follows:

[0105]

[0106] Interpolation is performed on each river channel point between the two cross-sections using a linear interpolation method. The formula for calculating the left-side inundation distance of the i-th river channel point is as follows:

[0107]

[0108] For each river channel point P between the two cross sections i Based on its relationship with the previous river channel point P i-1 The vertical direction of the line, the submerged distance D on the left side i and the previous riverbank point b i-1 Coordinates are used to determine the left bank point b corresponding to each river channel point. i The coordinates are given. Among them, riverbank point b1 is riverbank point S1, and riverbank point b7 is riverbank point E1.

[0109] According to river point P i-1 (x1, y1), river point P i (x2, y2), riverbank point b i-1 (x m ,y m ), left side flooding distance D i To calculate b i (x n ,y n The formula is as follows:

[0110]

[0111] dot=(x1-x m (x2-x) n )+(y1-y m )(y2-y n (8)

[0112]

[0113] In the formula, x' n ,y' n For b i The coordinates of the trial point are shown in dot. and The dot product, when dot > 0, represents and Angle less than 90°, b i Trial point and b i-1 On line P i-1 On the same side of P, b i The coordinates are taken from the trial point coordinates (x') n ,y' n When dot < 0, it means and Angle greater than 90°, b iWith b i-1 On line P i-1 On the opposite side of P, b needs to be adjusted. i The coordinate calculation formula yields b. i coordinates (x) n ,y n ).

[0114] Connecting point S1 on the left bank of the first river section, points b2 to b6 on the left bank, and point E1 on the left bank of the second river section, forms the left bank line. Calculate the perpendicular distance between point S2 on the right bank of the first river section and the line connecting the first two river points P1 and P2; calculate the perpendicular distance between point E2 on the right bank of the second river section and the line connecting the last two river points P6 and P7. Based on these two perpendicular distances, interpolate the inundation distances of each river point between the two sections to calculate the right bank inundation distance of each river point.

[0115] For each river channel point P between the two cross sections i Based on its relationship with the previous river channel point P i-1 The coordinates of the right bank point corresponding to each river channel point are determined by the vertical direction of the connecting line, the right-side submergence distance, and the coordinates of the previous riverbank point.

[0116] Connect the right bank point S2 of the first river section, all the right bank points, and the right bank point E2 of the second river section in sequence to form the right bank line.

[0117] Connect the beginning and end of the left and right riverbanks respectively to form a closed curve, which serves as the inundation range between the two sections.

[0118] The above operation is performed on every two adjacent cross-sections to obtain the inundation range of the entire river channel. For example... Figure 5 As shown.

[0119] By performing the above operation at each calculation time point, the change process of the entire river channel inundation range can be obtained.

[0120] This application also provides a river inundation mapping device based on cross-sectional water level, such as... Figure 6 As shown, it includes:

[0121] The loading module 10 is used to load Tianditu satellite imagery into the ArcGIS geographic information system, determine the target river channel in the Tianditu satellite imagery, and determine the centerline of the target river channel.

[0122] The first acquisition module 20 is used to define multiple river cross sections of the target river channel and acquire the cross section data, riverbed roughness, hourly flow rate at the upper boundary, and water level at the lower boundary for each river cross section; the cross section data includes: river cross section line and river cross section curve;

[0123] The first determining module 30 is used to determine the cross-sectional water level based on the river channel cross-sectional curve, the riverbed roughness, the hourly flow rate at the upper boundary, and the water level at the lower boundary.

[0124] The second determining module 40 is used to determine the river channel cross-section water level line based on the cross-section water level.

[0125] The second acquisition module 50 is used to acquire the first coordinates of the first cross-section riverbank point and the second coordinates of the second cross-section riverbank point. The two intersection points of the river cross-section water level line and the river cross-section curve are respectively the first cross-section riverbank point and the second cross-section riverbank point of the river cross-section. The first cross-section riverbank point belongs to the first side riverbank point, and the second cross-section riverbank point belongs to the second side riverbank point.

[0126] The third determining module 60 is used to divide the centerline of the river between two adjacent river sections into multiple river center segments at equal intervals, the connection point of the adjacent river center segments is the river point, and to determine the third coordinate of each river point.

[0127] Calculation module 70 is used to sequentially calculate the first inundation distance from the first cross-section riverbank point of each river channel to the target river channel center section, wherein the target river channel center section is the line connecting the two river points closest to the river channel cross-section.

[0128] The fourth determining module 80 is used to determine multiple second inundation distances based on the two first inundation distances corresponding to two adjacent river cross sections, wherein the second inundation distance is the vertical distance from each first side riverbank point to the corresponding nearest river center segment;

[0129] The fifth determining module 90 is used to determine the coordinates of a first side riverbank point adjacent to the first cross-section riverbank point based on the third coordinates of the river point closest to the river cross-section, the second inundation distance, and the first coordinates of the first cross-section riverbank point; and repeat this step to calculate the coordinates of other first side riverbank points and the coordinates of second side riverbank points;

[0130] The drawing module 100 is used to draw the first bank based on the coordinates of each first side riverbank point and to draw the second bank based on the coordinates of each second side riverbank point.

[0131] In one embodiment, the second determining module is further configured to use the river cross-section curve and the riverbed roughness as inputs to the one-dimensional hydrodynamic model, use the hourly flow rate of the upper boundary as the upper boundary condition of the one-dimensional hydrodynamic model (HEC-RAS model), and use the lower boundary water level as the lower boundary condition of the one-dimensional hydrodynamic model (HEC-RAS model), so that the one-dimensional hydrodynamic model (HEC-RAS model) outputs the cross-sectional water level.

[0132] In one embodiment, the fourth determining module is further configured to determine a plurality of second inundation distances by calculating the difference between the two first inundation distances corresponding to two adjacent river cross sections.

[0133] In one embodiment, a computer device is provided, including a memory and a processor, the memory storing a computer program that, when executed by the processor, causes the processor to perform the following steps:

[0134] Load Tianditu satellite imagery into the ArcGIS geographic information system, identify the target river channel in the Tianditu satellite imagery, and determine the centerline of the target river channel.

[0135] Define multiple river cross sections of the target river channel, and obtain the cross section data, riverbed roughness, hourly flow rate at the upper boundary, and water level at the lower boundary for each river cross section; the cross section data includes: river cross section line and river cross section curve;

[0136] The cross-sectional water level is determined based on the river channel cross-sectional curve, the riverbed roughness, the hourly flow rate at the upper boundary, and the water level at the lower boundary.

[0137] The river channel cross-section water level line is determined based on the cross-sectional water level.

[0138] Obtain the first coordinates of the first cross-section riverbank point and the second coordinates of the second cross-section riverbank point. The two intersection points of the river cross-section water level line and the river cross-section curve are respectively the first cross-section riverbank point and the second cross-section riverbank point of the river cross-section. The first cross-section riverbank point belongs to the first side riverbank point, and the second cross-section riverbank point belongs to the second side riverbank point.

[0139] The centerline between two adjacent river sections is divided into multiple river center segments at equal intervals. The connection point between adjacent river center segments is called a river point, and the third coordinate of each river point is determined.

[0140] Calculate the first inundation distance from the first cross-section riverbank point of each river channel to the target river channel center section in sequence, where the target river channel center section is the line connecting the two river channel points closest to the river channel cross-section.

[0141] Multiple second inundation distances are determined based on the two first inundation distances corresponding to two adjacent river cross sections, wherein the second inundation distance is the vertical distance from each first side bank point to the corresponding nearest river center segment;

[0142] Based on the third coordinate of the river point closest to the river cross-section, the second inundation distance, and the first coordinate of the first cross-section riverbank point, determine the coordinates of the first side riverbank point adjacent to the first cross-section riverbank point; and repeat this step to calculate the coordinates of other first side riverbank points and the coordinates of second side riverbank points.

[0143] Draw the first bank based on the coordinates of each first bank point, and draw the second bank based on the coordinates of each second bank point.

[0144] In one embodiment, a computer-readable storage medium is provided storing a computer program that, when executed by a processor, causes the processor to perform the following steps:

[0145] Load Tianditu satellite imagery into the ArcGIS geographic information system, identify the target river channel in the Tianditu satellite imagery, and determine the centerline of the target river channel.

[0146] Define multiple river cross sections of the target river channel, and obtain the cross section data, riverbed roughness, hourly flow rate at the upper boundary, and water level at the lower boundary for each river cross section; the cross section data includes: river cross section line and river cross section curve;

[0147] The cross-sectional water level is determined based on the river channel cross-sectional curve, the riverbed roughness, the hourly flow rate at the upper boundary, and the water level at the lower boundary.

[0148] The river channel cross-section water level line is determined based on the cross-sectional water level.

[0149] Obtain the first coordinates of the first cross-section riverbank point and the second coordinates of the second cross-section riverbank point. The two intersection points of the river cross-section water level line and the river cross-section curve are respectively the first cross-section riverbank point and the second cross-section riverbank point of the river cross-section. The first cross-section riverbank point belongs to the first side riverbank point, and the second cross-section riverbank point belongs to the second side riverbank point.

[0150] The centerline between two adjacent river sections is divided into multiple river center segments at equal intervals. The connection point between adjacent river center segments is called a river point, and the third coordinate of each river point is determined.

[0151] Calculate the first inundation distance from the first cross-section riverbank point of each river channel to the target river channel center section in sequence, where the target river channel center section is the line connecting the two river channel points closest to the river channel cross-section.

[0152] Multiple second inundation distances are determined based on the two first inundation distances corresponding to two adjacent river cross sections, wherein the second inundation distance is the vertical distance from each first side bank point to the corresponding nearest river center segment;

[0153] Based on the third coordinate of the river point closest to the river cross-section, the second inundation distance, and the first coordinate of the first cross-section riverbank point, determine the coordinates of the first side riverbank point adjacent to the first cross-section riverbank point; and repeat this step to calculate the coordinates of other first side riverbank points and the coordinates of second side riverbank points.

[0154] Draw the first bank based on the coordinates of each first bank point, and draw the second bank based on the coordinates of each second bank point.

[0155] Figure 7 An internal structural diagram of a computer device in one embodiment is shown. This computer device can specifically be a terminal or a server. Figure 7 As shown, the computer device includes a processor, memory, and network interface connected via a system bus. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system and may also store a computer program. When executed by the processor, this computer program enables the processor to implement a method for mapping river channel inundation based on cross-sectional water levels. The internal memory may also store a computer program, which, when executed by the processor, enables the processor to implement the method for mapping river channel inundation based on cross-sectional water levels. Those skilled in the art will understand that... Figure 7 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0156] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments described above. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and RAMbus dynamic RAM (RDRAM), etc.

[0157] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0158] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A method for mapping river inundation based on cross-sectional water level, wherein the first bank of the river is composed of a plurality of first side bank points, and the second bank of the river is composed of a plurality of second side bank points, wherein the first side bank points and the second side bank points are located on opposite sides of the river centerline, characterized in that, The method includes: Load Tianditu satellite imagery into the ArcGIS geographic information system, identify the target river channel in the Tianditu satellite imagery, and determine the centerline of the target river channel. Define multiple river cross sections of the target river channel, and obtain the cross section data, riverbed roughness, hourly flow rate at the upper boundary, and water level at the lower boundary for each river cross section; the cross section data includes: river cross section line and river cross section curve; The cross-sectional water level is determined based on the river channel cross-sectional curve, the riverbed roughness, the hourly flow rate at the upper boundary, and the water level at the lower boundary. The river channel cross-section water level line is determined based on the cross-sectional water level. Obtain the first coordinates of the first cross-section riverbank point and the second coordinates of the second cross-section riverbank point. The two intersection points of the river cross-section water level line and the river cross-section curve are respectively the first cross-section riverbank point and the second cross-section riverbank point of the river cross-section. The first cross-section riverbank point belongs to the first side riverbank point, and the second cross-section riverbank point belongs to the second side riverbank point. The centerline between two adjacent river sections is divided into multiple river center segments at equal intervals. The connection point between adjacent river center segments is called a river point, and the third coordinate of each river point is determined. Calculate the first inundation distance from the first cross-section riverbank point of each river channel to the target river channel center section in sequence, where the target river channel center section is the line connecting the two river channel points closest to the river channel cross-section. Multiple second inundation distances are determined based on the two first inundation distances corresponding to two adjacent river cross sections, wherein the second inundation distance is the vertical distance from each first side bank point to the corresponding nearest river center segment; Based on the third coordinate of the river point closest to the river cross-section, the second inundation distance, and the first coordinate of the first cross-section riverbank point, determine the coordinates of the first side riverbank point adjacent to the first cross-section riverbank point; and repeat this step to calculate the coordinates of other first side riverbank points and the coordinates of second side riverbank points. Draw the first bank based on the coordinates of each first bank point, and draw the second bank based on the coordinates of each second bank point.

2. The method for mapping river inundation based on cross-sectional water level according to claim 1, characterized in that, The step of determining the cross-sectional water level based on the river channel cross-sectional curve, the riverbed roughness, the hourly flow rate at the upper boundary, and the water level at the lower boundary includes: The river channel cross-sectional curve and the riverbed roughness are used as inputs to a one-dimensional hydrodynamic model. The hourly flow rate at the upper boundary is used as the upper boundary condition of the one-dimensional hydrodynamic model, and the water level at the lower boundary is used as the lower boundary condition of the one-dimensional hydrodynamic model, so that the one-dimensional hydrodynamic model outputs the cross-sectional water level.

3. The method for drawing river channel inundation based on cross-sectional water level according to claim 1, characterized in that, The determination of multiple second inundation distances based on the two first inundation distances corresponding to two adjacent river cross sections includes: Multiple second inundation distances are determined by calculating the difference between the two first inundation distances corresponding to two adjacent river sections.

4. The method for drawing river channel inundation based on cross-sectional water level according to claim 1, characterized in that, The first flooding distance is calculated as follows: Where D1 is the first inundation distance, and the coordinates of the first cross-section riverbank point S1 are (x... s ,y s The coordinates of the two river points closest to the river cross-section are P1(x1,y1) and P2(x2,y2).

5. The method for drawing river channel inundation based on cross-sectional water level according to claim 4, characterized in that, The second flooding distance is calculated as follows: Among them, D i For the second flooding distance, D1 and D n These are the two first inundation distances corresponding to two adjacent river cross sections, where i is the i-th riverbank point and n is the n-th riverbank point.

6. A river inundation mapping device based on cross-sectional water level, characterized in that, include: The loading module is used to load Tianditu satellite imagery into the ArcGIS geographic information system, determine the target river channel in the Tianditu satellite imagery, and determine the centerline of the target river channel. The first acquisition module is used to define multiple river cross sections of the target river channel and acquire the cross section data, riverbed roughness, hourly flow rate at the upper boundary, and water level at the lower boundary for each river cross section; the cross section data includes: river cross section line and river cross section curve; The first determining module is used to determine the cross-sectional water level based on the river channel cross-sectional curve, the riverbed roughness, the hourly flow rate at the upper boundary, and the water level at the lower boundary. The second determining module is used to determine the river channel cross-section water level line based on the cross-section water level. The second acquisition module is used to acquire the first coordinates of the first cross-section riverbank point and the second coordinates of the second cross-section riverbank point. The two intersection points of the river cross-section water level line and the river cross-section curve are respectively the first cross-section riverbank point and the second cross-section riverbank point of the river cross-section. The first cross-section riverbank point belongs to the first side riverbank point, and the second cross-section riverbank point belongs to the second side riverbank point. The third determining module is used to divide the centerline of the river between two adjacent river sections into multiple river center segments at equal intervals, the connection point of the adjacent river center segments is the river point, and the third coordinate of each river point is determined. The calculation module is used to sequentially calculate the first inundation distance from the first cross-section riverbank point of each river section to the target river center section, wherein the target river center section is the line connecting the two river points closest to the river section. The fourth determining module is used to determine multiple second inundation distances based on the two first inundation distances corresponding to two adjacent river cross sections, wherein the second inundation distance is the vertical distance from each first side riverbank point to the corresponding nearest river center segment; The fifth determining module is used to determine the coordinates of a first side riverbank point adjacent to the first cross-section riverbank point based on the third coordinate of the river point closest to the river cross-section, the second inundation distance, and the first coordinate of the first cross-section riverbank point; and repeat this step to calculate the coordinates of other first side riverbank points and the coordinates of second side riverbank points; The drawing module is used to draw the first bank based on the coordinates of each first riverbank point and the second bank based on the coordinates of each second riverbank point.

7. The river inundation mapping device based on cross-sectional water level according to claim 6, characterized in that, The second determining module is further configured to use the river channel cross-sectional curve and the riverbed roughness as inputs to the one-dimensional hydrodynamic model, use the hourly flow rate of the upper boundary as the upper boundary condition of the one-dimensional hydrodynamic model, and use the water level of the lower boundary as the lower boundary condition of the one-dimensional hydrodynamic model, so that the one-dimensional hydrodynamic model outputs the cross-sectional water level.

8. The river inundation mapping device based on cross-sectional water level according to claim 6, characterized in that, The fourth determining module is also used to determine multiple second inundation distances by calculating the difference between the two first inundation distances corresponding to two adjacent river sections.

9. A computer device comprising a memory and a processor, the memory storing a computer program that, when executed by the processor, causes the processor to perform the steps of the method as claimed in any one of claims 1 to 5.

10. A computer-readable storage medium storing a computer program that, when executed by a processor, causes the processor to perform the steps of the method as claimed in any one of claims 1 to 5.

Images