Method for calculating river inflow of urban drainage system based on GIS platform and open source data

Abstract

The application provides a kind of urban drainage system river-entering water quantity calculation method and system based on GIS platform and open source data, which comprises obtaining open source data of drainage area to construct basic database and store it in GIS platform;Based on the spatial resolution of open source GIS data in the basic database, the drainage area is divided into multiple independent calculation units and the parameter value of each independent calculation unit is obtained;Construct the runoff model of each independent calculation unit and combine the parameter value of each independent calculation unit to obtain the runoff and sewage flow of each independent calculation unit;The concentration flow of the drainage area is obtained by using the transport time algorithm;Based on the concentration flow of the drainage area and combined with the treatment capacity of the sewage plant in the drainage area, the river-entering water quantity of the drainage area is obtained.The method of the application is easy to obtain, widely applicable, and has high reliability and high time accuracy of the calculation result, which is helpful for the control and management of urban runoff pollution.

Description

Technical Field

[0001] The present invention relates to the technical field of drainage system river inflow statistics, and in particular to a method and system for calculating the river inflow of an urban drainage system based on a GIS platform and open source data. Background Art

[0002] Due to my country's growing population, rising socioeconomic status, and urbanization, urban environmental pollution problems such as black and odorous water bodies and substandard water quality have become frequent, and urban water pollution is receiving increasing attention. In recent years, with increased policy attention and investment in governance, the contribution of point sources to urban water pollution has declined annually. In contrast, the contribution of urban runoff pollution has increased annually, becoming the primary factor affecting urban water pollution and ecological degradation.

[0003] Urban runoff pollution is closely linked to rainfall, underlying surface, and topography, and is particularly closely linked to urban drainage systems. Pollutants on urban surfaces, driven by rainfall runoff, enter the urban drainage system. After being transported and treated by the drainage system, the water entering rivers and lakes can cause water pollution. Therefore, accurately calculating the amount of water entering rivers from urban drainage systems is fundamental and crucial for implementing runoff pollution control and management.

[0004] The main methods for quantitatively calculating the amount of water flowing into rivers from urban drainage systems are empirical models and mechanistic models. Empirical models are "black box" models that simulate regional spatial characteristics in an averaged manner. A commonly used empirical model is the output coefficient method. This method is simple in structure and easy to obtain data, but it ignores the spatial variability and complex migration and transformation processes of sewage and rainfall runoff, resulting in low accuracy. Mechanistic models, based on the inherent mechanisms of urban runoff formation, simulate the formation of sewage and rainfall runoff, as well as the migration and transformation of pollutants, through mathematical models. Commonly used mechanistic models include SWMM and HSPF. Their mechanisms and processes are relatively clear, resulting in high accuracy and good portability. However, these models often require large amounts of data and require long modeling times. However, domestic cities often lack detailed basic data (especially drainage network data), which often limits the use of mechanistic models. Therefore, it is necessary to overcome this data shortage and develop calculation methods to better calculate the amount of water flowing into rivers from urban drainage systems. Summary of the Invention

[0005] The present invention aims to provide a method for calculating the amount of water flowing into rivers from urban drainage systems, based on a GIS platform and open-source data. This method addresses the technical issues with existing models, which suffer from low accuracy or high accuracy but require detailed basic data, hindering widespread adoption. The various technical benefits of the preferred solutions provided by this invention are detailed below.

[0006] To achieve the above objectives, the present invention provides the following technical solutions:

[0007] The present invention provides a method for calculating the amount of water flowing into a river from an urban drainage system based on a GIS platform and open source data, comprising:

[0008] Obtain open source data of the drainage area to be calculated to build a basic database, and store the basic database on the GIS platform;

[0009] Dividing the drainage area to be calculated into a plurality of independent calculation units based on the spatial resolution of the open source GIS data obtained in the basic database, and obtaining a parameter value for each independent calculation unit according to the open source GIS data in the basic database;

[0010] Construct a runoff model for each independent calculation unit and combine the parameter values ​​of each independent calculation unit to obtain the runoff flow and sewage flow of each independent calculation unit;

[0011] The combined flow rate of the drainage area is obtained by using the transport time algorithm and combining the runoff flow and sewage flow of each independent calculation unit;

[0012] Based on the drainage area's confluence flow and combined with the drainage area's sewage treatment plant treatment capacity, the drainage area's river water volume is obtained.

[0013] According to a preferred embodiment, the open source data of the drainage area to be calculated is obtained from domestic and foreign data websites and public information.

[0014] The open source data include the underlying surface data of the drainage area to be calculated, DEM data, soil structure data, population distribution data, per capita water consumption data and pollution reduction coefficient, rainfall data and the treatment capacity of the sewage treatment plant in the drainage area.

[0015] According to a preferred embodiment, the method of dividing the drainage area to be calculated into a plurality of independent calculation units based on the spatial resolution of the open source GIS data obtained in the basic database comprises:

[0016] According to the spatial resolution of the open source GIS data in the basic database, the smallest spatial resolution is selected as the spatial resolution of each independent calculation unit to divide the drainage area into multiple square grids G j,k , where j and k are the row and column numbers of each square grid, respectively, and each square grid serves as an independent calculation unit.

[0017] According to a preferred embodiment, the parameter values ​​of each independent calculation unit are obtained based on the open source GIS data in the basic database; wherein the parameter values ​​include: rainfall parameter values, geometric parameter values, spatial parameter values, population parameter values ​​and water consumption parameter values,

[0018] The rainfall parameter value includes the rainfall data p at any time i i and the calculation step length δt, which is the rainfall data time step length; the geometric parameter values ​​include the area A and width W of the independent calculation unit, and the distance x between each independent calculation unit and the sewage treatment plant in the drainage area; the spatial parameter values ​​include whether the independent calculation unit is permeable and the Manning roughness coefficient η obtained according to the underlying surface data, the stable permeability coefficient f of the independent calculation unit obtained by the ratio of sand, silt and clay according to the soil structure data, and the slope g obtained according to the DEM data; the population parameter value includes the population r of the independent calculation unit obtained by spatial calculation based on the spatial relationship between the population data and the independent calculation unit; the water consumption parameter value includes the per capita water consumption u and the pollution reduction coefficient γ of the independent calculation unit obtained according to the per capita water consumption data. According to a preferred embodiment, the runoff flow and sewage flow of each independent calculation unit are obtained by constructing a runoff generation and confluence model for each independent calculation unit and combining the parameter values ​​of each independent calculation unit; including:

[0019] Based on the Horton infiltration model and the nonlinear reservoir confluence model, the runoff model of the independent calculation unit is constructed, and the parameter values ​​of the independent calculation unit are brought in to calculate the runoff flow q of the independent calculation unit. i ;as well as

[0020] Calculate the sewage flow rate of the independent calculation unit l based on the population parameter value and water consumption parameter value i =r×u×γ.

[0021] According to a preferred embodiment, the runoff model of the independent calculation unit constructed based on the Horton infiltration model and the nonlinear reservoir runoff model includes:

[0022] When constructing the Horton infiltration model, the change of the permeability coefficient over time is ignored and the permeability coefficient is regarded as a stable value; when constructing the nonlinear reservoir confluence model, the effect of evaporation is ignored and the depression depth is not considered;

[0023] Based on the Horton infiltration model and nonlinear reservoir confluence model, the finite difference equation of the surface water depth h of the independent calculation unit is constructed, and the surface water depth h of the independent calculation unit is obtained. i The approximate value of h is obtained by iterative solution using the Newton-Raphson iteration method by setting the initial value and the stopping condition of the iteration.

[0024] Surface water h calculated by independent calculation unit i Get the runoff flow q of the independent calculation unit i .

[0025] According to a preferred embodiment, the method of using the travel time algorithm and combining the runoff flow and sewage flow of each independent calculation unit to obtain the drainage area's combined flow includes:

[0026] Obtain the transport time of runoff flow and sewage flow of independent calculation units to the sewage treatment plant Transfer time t i Divide by the calculation step size δt and round up to get n i ;

[0027] Calculate the drainage area's confluent flow Q i ,

[0028]

[0029] According to a preferred embodiment, the method of obtaining the amount of water flowing into the river in the drainage area based on the confluence flow of the drainage area and the treatment capacity of the sewage treatment plant in the drainage area includes:

[0030] When the sub-catchment is divided into diversion systems, the resulting drainage area flow Q i The amount of water flowing into the river in the drainage area to be calculated

[0031] When the sub-catchment is a combined system, the amount of water flowing into the river in the drainage area to be calculated is Confluence flow Q with drainage area i and sewage treatment capacity Related:

[0032] The present invention also provides a system for calculating the amount of water flowing into rivers from urban drainage systems based on a GIS platform and open source data, comprising:

[0033] The acquisition module is used to obtain the open source data of the drainage area to be calculated to build a basic database and store the basic database on the GIS platform;

[0034] a processing module, configured to divide the drainage area to be calculated into a plurality of independent calculation units based on the spatial resolution of the open source GIS data obtained in the basic database, and obtain a parameter value of each independent calculation unit according to the open source GIS data in the basic database;

[0035] The model building module is used to build the runoff model of each independent calculation unit and combine the parameter values ​​of each independent calculation unit to obtain the runoff flow and sewage flow of each independent calculation unit;

[0036] The calculation module is used to use the transport time algorithm and combine the runoff flow and sewage flow of each independent calculation unit to obtain the drainage area's confluence flow; and based on the drainage area's confluence flow and combined with the drainage area's sewage treatment plant treatment capacity, obtain the drainage area's river water volume.

[0037] Based on the above technical solution, the method and system for calculating the amount of water entering the river from the urban drainage system based on the GIS platform and open source data of the present invention have at least the following technical effects:

[0038] 1. The calculation method of the present invention fully considers the actual situation. All calculation data are obtained through public channels and a database is constructed. The available open source data is used to simplify the mechanism model, reduce the data requirements of the calculation method, and ensure the applicability of the calculation method. The present invention performs calculations based on open source data, which has the advantages of low data requirements and wide applicability.

[0039] 2. This method uses spatial gridding to divide independent computational units, each with its own attribute values ​​and independent calculations. This fully accounts for the spatial heterogeneity of the study area and provides a highly reliable computational method. Within the GIS platform, a distributed runoff model is constructed, using the Horton infiltration model and a nonlinear reservoir model as core mechanisms. The transport process is simulated using a travel time algorithm, resulting in a clear overall method mechanism.

[0040] 3. The method of the present invention can simulate the spatiotemporal variation of the amount of water entering the river from the urban drainage system with high temporal accuracy, thereby better assisting the design of urban runoff pollution control projects and thus more efficiently controlling and managing urban runoff pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0042] Figure 1 It is a block diagram of the method for calculating the amount of water entering a river from an urban drainage system based on a GIS platform and open source data of the present invention;

[0043] Figure 2This is a schematic diagram of collecting open source data, building a basic database, and storing it on a GIS platform in Example 2 of the present invention;

[0044] Figure 3 is a schematic diagram of rainfall data obtained from the National Meteorological Science Data Center in Example 2 of the present invention;

[0045] Figure 4 This is a schematic diagram of the calculation results of the amount of water entering the river from the drainage area according to the second embodiment of the present invention;

[0046] Figure 5 This is a schematic diagram of the present invention collecting detailed pipe network data of the drainage area and constructing the SWMM model;

[0047] Figure 6 1 is a comparison diagram of the calculation structure of the calculation method of Example 2 of the present invention and the mechanism method;

[0048] Figure 7 This is a block diagram of the urban drainage system river inflow calculation system based on the GIS platform and open source data of the present invention. DETAILED DESCRIPTION

[0049] To make the objectives, technical solutions, and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other implementations obtained by those of ordinary skill in the art without inventive effort are within the scope of protection of the present invention.

[0050] Example 1

[0051] This embodiment provides a method for calculating the amount of water flowing into a river from an urban drainage system based on a GIS platform and open source data, including the following steps:

[0052] S101: Obtain open source data of the drainage area to be calculated to build a basic database, and store the basic database on a GIS platform.

[0053] Specifically, the open source data of the drainage area to be calculated is obtained through domestic and foreign data websites and public information, that is, the open source data is obtained from domestic and foreign data websites and public resources, and is used to build a basic database. Preferably, the open source data includes the underlying surface data, DEM data, soil structure data, population distribution data, per capita water consumption data and pollution reduction coefficient, rainfall data, and drainage area sewage treatment plant treatment capacity of the drainage area to be calculated. The method of the present invention fully considers the domestic reality. All calculation data can be obtained through public channels. Through the available open source data, the mechanism model is simplified, the data requirements of the calculation method are reduced, and the applicability of the calculation method is guaranteed.

[0054] S102: Divide the drainage area to be calculated into multiple independent calculation units based on the spatial resolution of the open source GIS data in the basic database, and obtain parameter values ​​of each independent calculation unit according to the open source GIS data in the basic database.

[0055] Specifically, according to the spatial resolution of the open source GIS data in the basic database, the smallest spatial resolution is selected as the spatial resolution of each independent calculation unit to divide the drainage area into multiple square grids G j,k , where j and k are the row and column numbers of each square grid, respectively, and each square grid serves as an independent calculation unit.

[0056] Preferably, the parameter values ​​of each independent calculation unit are obtained based on the open source GIS data in the basic database; wherein the parameter values ​​include: rainfall parameter values, geometric parameter values, spatial parameter values, population parameter values ​​and water consumption parameter values.

[0057] (1) Rainfall parameter value: rainfall data p at any time i i And the calculation step length δt, which is the time step length of the rainfall data.

[0058] (2) Geometric parameter values: area A and width W of the independent calculation unit, and the distance x between each independent calculation unit and the sewage treatment plant in the drainage area.

[0059] (3) Spatial parameter values: whether the independent calculation unit is permeable and the Manning roughness coefficient η obtained from the underlying surface data, the stable permeability coefficient f of the independent calculation unit obtained from the ratio of sand, silt and clay particles based on the soil structure data, and the slope g obtained from the DEM data.

[0060] (4) Population parameter value: The population r of an independent calculation unit obtained by spatial calculation based on the population data and the spatial relationship between the independent calculation units.

[0061] (5) Water consumption parameter value: the per capita water consumption u and pollution reduction coefficient γ of the independent calculation unit obtained based on the per capita water consumption data.

[0062] S103: constructing a runoff generation and confluence model for each independent calculation unit and combining the parameter values ​​of each independent calculation unit to obtain the runoff flow and sewage flow of each independent calculation unit;

[0063] Specifically: including:

[0064] S201: Based on the Horton infiltration model and the nonlinear reservoir confluence model, a runoff model for the independent calculation unit is constructed, and the parameter values ​​of the independent calculation unit are introduced to calculate the runoff flow q of the independent calculation unit. i ;

[0065] Specifically, the runoff generation and confluence model of the independent calculation unit is constructed based on the Horton infiltration model and the nonlinear reservoir confluence model, including:

[0066] When constructing the Horton infiltration model, the change of the permeability coefficient over time is ignored and the permeability coefficient is regarded as a stable value; when constructing the nonlinear reservoir confluence model, the influence of evaporation is ignored and the depression depth is not considered.

[0067] Specifically, based on the simplified Horton infiltration model and nonlinear reservoir confluence model, the runoff model of the independent calculation unit is constructed, and the parameter values ​​of the independent calculation unit are brought in to calculate the runoff flow q of the independent calculation unit. i , including constructing the finite difference equation of the surface water depth h of the independent calculation unit based on the above Horton infiltration model and nonlinear reservoir confluence model, and obtaining the surface water depth h of the independent calculation unit i The approximate value of h is obtained by iterative solution using the Newton-Raphson iteration method by setting the initial value and the stopping condition of the iteration.

[0068] Surface water h calculated by independent calculation unit i Get the runoff flow q of the independent calculation unit i .

[0069] S201: Calculate the sewage flow rate l of the independent calculation unit based on the population parameter value and the water consumption parameter value i =r×u×γ.

[0070] S104: using a transport time algorithm and combining the runoff flow and sewage flow of each independent calculation unit to obtain the drainage area's combined flow;

[0071] Specifically, it includes:

[0072] Obtain the transport time of runoff flow and sewage flow of independent calculation units to the sewage treatment plant Transfer time t i Divide by the calculation step size δt and round up to get n i ;

[0073] Calculate the drainage area's confluent flow Q i ,

[0074]

[0075] S105: Based on the drainage area's confluent flow and the sewage treatment plant's treatment capacity, the amount of water flowing into the river in the drainage area is obtained;

[0076] Specifically, it includes:

[0077] When the sub-catchment is divided into diversion systems, the resulting drainage area flow Q i The amount of water flowing into the river in the drainage area to be calculated

[0078] When the sub-catchment is a combined system, the amount of water flowing into the river in the drainage area to be calculated is Confluence flow Q with drainage area i and sewage treatment capacity Related:

[0079] The proposed calculation method utilizes spatial gridding to create independent computational units, each with its own attribute values ​​and independent calculations, fully accounting for the spatial heterogeneity of the study area. Within a GIS platform, a distributed runoff model is constructed, using the Horton infiltration model and a nonlinear reservoir model as core mechanisms. The transport process is simulated using a travel time algorithm, resulting in a clear overall method.

[0080] Example 2

[0081] This embodiment 2 takes a city's combined sewer area as an example to specifically illustrate the calculation method of the present invention. This embodiment selects a city's combined sewer area with an area of ​​710.7ha and a sewage treatment plant with a design scale of 20,000 m 3 / d.

[0082] 1. Obtain open source data, build a basic database, and store it on a GIS platform, such as Figure 2 As shown:

[0083] The underlying surface data, DEM data, soil structure data, population distribution data, per capita water consumption data and pollution reduction coefficient of the drainage area were obtained.

[0084] The underlying surface data was obtained from the open-source GIS data of Tsinghua University (http: / / data.ess.tsinghua.edu.cn / ) with a resolution of 10m×10m.

[0085] DEM data: Open source GIS data were obtained from the Geospatial Data Cloud (https: / / www.gscloud.cn / home) with a resolution of 30 m × 30 m.

[0086] Soil structure data: Open source GIS data were obtained from FAO (https: / / www.fao.org / soils-portal / soil-survey / soil-maps-and-databases / harmonized-world-soil-database-v12 / en / ) with a resolution of 800 m × 800 m.

[0087] Population distribution data: Open source GIS data were obtained from WorldPop (https: / / www.worldpop.org) with a resolution of 100m × 100m.

[0088] Rainfall data: Open source data is obtained from the National Meteorological Science Data Center (http: / / data.cma.cn / ). The data accuracy is hourly and the time range is from 09:00 on July 5, 2021 to 09:00 on July 14, 2021. The data is as follows: Figure 3 shown.

[0089] Per capita water consumption data: Per capita water consumption data and pollution reduction coefficients for different regions were obtained from the Second National Pollution Census - Handbook of Pollution Generation and Emission Coefficients for Domestic Pollution Sources.

[0090] 2. Division of independent computing units and determination of parameter values.

[0091] The minimum spatial resolution of open source GIS data is used as the resolution of the independent calculation unit, that is, 10m×10m.

[0092] Compute parameter values ​​for independent computational units:

[0093] (1) Rainfall parameters: rainfall data p i like Figure 3 , calculation step δt = 1h;

[0094] (2) Geometric parameters: The area of ​​the independent calculation unit is A = 100 m and the width is W = 10 m. The distance x from the independent calculation unit to the sewage treatment plant in the drainage area is calculated using the GIS platform.

[0095] (3) Spatial parameter values: Based on the underlying surface data, the underlying surface is divided into four categories: green land, bare land, and impervious ground. Except for impervious ground, the other underlying surfaces are permeable, which is used to determine whether the independent calculation unit is permeable. For the impervious independent calculation unit, the stable permeability coefficient f = 0 mm / h is set, and the Manning roughness coefficient η is given according to the underlying surface type. According to the technical data, η for impervious ground is 0.013. For the pervious independent calculation unit, based on the soil structure data, clay particles are the main component. Therefore, according to the technical data, the stable permeability coefficient f = 6 mm / h for the independent calculation unit of the pervious underlying surface is obtained. At the same time, the Manning roughness coefficient η is obtained, which is 0.075 for green land and 0.015 for bare land. The slope g is calculated based on the DEM data and ranges from 0 to 12°.

[0096] (4) Population parameter value: Based on the spatial relationship between population data and independent calculation units, spatial operations are performed to obtain the population r of independent calculation units in the range of 40-100 people / hm2. 2 .

[0097] (5) Water volume parameter value: Based on the per capita water consumption data, the per capita water consumption of the independent calculation unit is u = 148 L / person·d, and the pollution reduction coefficient γ = 0.85.

[0098] 3. In the GIS platform, calculate the runoff flow and sewage flow of independent calculation units.

[0099] (1) Calculation of runoff flow of independent calculation units.

[0100] Refer to Horton's infiltration model, ignore the change of permeability coefficient over time, and regard the permeability coefficient as a stable value: r = Pf ∞ , where r is the surface runoff rate, m / s; f ∞ It is the stable value of infiltration capacity, which is the infiltration capacity when the soil reaches the field water holding capacity, called the stable infiltration rate, m / s.

[0101] Based on the nonlinear reservoir method assumption and ignoring the effect of evaporation in the urban catchment area, the calculation formula is as follows:

[0102] Where h is the surface water depth, m; dis is the surface runoff rate, m / s.

[0103] Calculated using Manning's formula:

[0104] Where Dis is the slope outflow m 3 / s;

[0105]

[0106] therefore:

[0107]

[0108] The finite difference form of the above equation is:

[0109] The Newton-Raphson iteration method is used to solve the approximate solution of the above equation:

[0110] make

[0111] Then the derivative of f(x) is

[0112] The iteration formula is as follows:

[0113]

[0114] Take the initial value x0 (usually set x0 = h i-1 ), then we can solve:

[0115]

[0116] Then from x1, solve:

[0117]

[0118] The above process is repeated until f(x n )<0.0001, the cycle stops, at this time h i =x n ,

[0119] By h i Then we can solve for q i :

[0120]

[0121] (2) Calculation of sewage flow in independent calculation units.

[0122] The unit sewage flow l is calculated independently based on the population parameter value and the water volume parameter value i =r×u×γ.

[0123] 4. Calculate the amount of water flowing into the river from the drainage area.

[0124] In the GIS platform, the flow rate of the drainage area is calculated by combining the calculation results of the runoff flow and sewage flow of the independent unit using the transport time algorithm; based on the flow rate of the drainage area and the operation status of the sewage treatment plant in the drainage area, the water inflow into the river in the drainage area is obtained. The calculation results are as follows: Figure 4 .

[0125] 5. Comparison of the calculation results of this method with those of the mechanism method.

[0126] (1) Figure 5 As shown in the figure, detailed pipe network data of the drainage area is collected, a SWMM model is constructed, and the amount of water entering the river in the drainage area is calculated.

[0127] (2) Compare the calculation results of this method and the mechanism method, such as Figure 6 .

[0128] The results show that from 09:00 on July 5, 2021 to 09:00 on July 14, 2021, the calculation results of this method show that the amount of water entering the river in the drainage area is 680,000 m 3 The SWMM calculation results show that the amount of water entering the river in the drainage area is 620,000 m 3 Therefore, the total amount of water flowing into the river from the drainage area calculated by the two methods is not much different. Furthermore, the changing trends of water flowing into the river from the drainage area calculated by the two methods are basically the same. Therefore, the calculation results of this method can be considered valid.

[0129] Example 3

[0130] This embodiment provides a system for calculating the amount of water flowing into rivers from urban drainage systems based on a GIS platform and open source data. Figure 7 Shown, including:

[0131] An acquisition module 101 is used to acquire open source data of the drainage area to be calculated to build a basic database, and store the basic database on a GIS platform;

[0132] The processing module 102 is configured to divide the drainage area to be calculated into a plurality of independent calculation units based on the spatial resolution of the open source GIS data obtained in the basic database, and obtain a parameter value for each independent calculation unit according to the open source GIS data in the basic database;

[0133] The model building module 103 is used to build a runoff generation and confluence model for each independent calculation unit and combine the parameter values ​​of each independent calculation unit to obtain the runoff flow and sewage flow of each independent calculation unit;

[0134] The calculation module 104 is used to use the transport time algorithm and combine the runoff flow and sewage flow of each independent calculation unit to obtain the drainage area's confluence flow; and based on the drainage area's confluence flow and combined with the drainage area's sewage treatment plant treatment capacity, obtain the drainage area's river water volume.

[0135] The method for calculating the amount of water entering a river in an urban drainage system based on a GIS platform and open source data of the present invention can be executed by a computer program. The computer program is stored in a memory, and the memory is connected to a processor for calling and executing the computer program in the memory through the processor.

[0136] It can be understood that the same or similar parts of the above embodiments can be referenced to each other, and the contents not described in detail in some embodiments can refer to the same or similar contents in other embodiments.

[0137] It should be noted that, in the description of the present invention, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance. In addition, in the description of the present invention, unless otherwise specified, the meaning of "plurality" is at least two.

[0138] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may be performed out of the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by those skilled in the art to which the embodiments of the present invention pertain.

[0139] It should be understood that various parts of the present invention can be implemented using hardware, software, firmware, or a combination thereof. In the above-described embodiments, multiple steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof can be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application-specific integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0140] Those skilled in the art will understand that all or part of the steps in the method of the above embodiment can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiment.

[0141] In addition, the functional units in the various embodiments of the present invention may be integrated into a single processing module, or each unit may exist physically separately, or two or more units may be integrated into a single module. The aforementioned integrated modules may be implemented in the form of hardware or in the form of software functional modules. If the integrated modules are implemented in the form of software functional modules and sold or used as independent products, they may also be stored in a computer-readable storage medium.

[0142] The storage medium mentioned above can be a read-only memory, a magnetic disk or an optical disk, etc.

[0143] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0144] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A method for calculating the amount of water flowing into a river from an urban drainage system based on a GIS platform and open source data, characterized in that: include: Obtain open source data of the drainage area to be calculated to build a basic database, and store the basic database on the GIS platform; Dividing the drainage area to be calculated into a plurality of independent calculation units based on the spatial resolution of the open source GIS data obtained in the basic database, and obtaining a parameter value for each independent calculation unit according to the open source GIS data in the basic database; Construct a runoff generation and confluence model for each independent calculation unit and combine the parameter values ​​of each independent calculation unit to obtain the runoff flow and sewage flow of each independent calculation unit; use the transport time algorithm and combine the runoff flow and sewage flow of each independent calculation unit to obtain the confluence flow of the drainage area; Based on the drainage area's confluence flow and combined with the drainage area's sewage treatment plant treatment capacity, the drainage area's river water volume is obtained; The parameter values ​​of each independent calculation unit are obtained according to the open source GIS data in the basic database; wherein the parameter values ​​include: rainfall parameter values, geometric parameter values, spatial parameter values, population parameter values ​​and water consumption parameter values, and the rainfall parameter values ​​include any i Rainfall data at the moment And calculate the step size , the calculation step is the rainfall data time step; the geometric parameter value includes the independent calculation unit area A and width W , and the distance between each independent calculation unit and the sewage treatment plant in the drainage area x The spatial parameter values ​​include whether the independent calculation unit is permeable and the Manning roughness coefficient obtained based on the underlying surface data , the stable permeability coefficient of the independent calculation unit obtained by the ratio of sand, silt and clay based on soil structure data And the slope obtained from DEM data The population parameter value includes the population of the independent calculation unit obtained by spatial calculation based on the spatial relationship between the population data and the independent calculation unit. r The water consumption parameter value includes the per capita water consumption of the independent calculation unit obtained based on the per capita water consumption data u and contamination coefficient γ ; The method uses the transfer time algorithm and combines the runoff flow and sewage flow of each independent calculation unit to obtain the confluence flow of the drainage area; including: obtaining the transfer time of the runoff flow and sewage flow of the independent calculation unit to the sewage treatment plant , transfer time Divide by the calculation step size , and round up to get ; Calculate the drainage area's confluence flow Q i , 2. The method for calculating the amount of water flowing into a river from an urban drainage system based on a GIS platform and open source data according to claim 1 is characterized in that: The open source data for the drainage area to be calculated is obtained through domestic and foreign data websites and public information. The open source data includes the underlying surface data, DEM data, soil structure data, population distribution data, per capita water consumption data and pollution reduction coefficient, rainfall data and the treatment capacity of the sewage treatment plant in the drainage area.

3. The method for calculating the amount of water flowing into a river from an urban drainage system based on a GIS platform and open source data according to claim 2 is characterized in that: The method of dividing the drainage area to be calculated into multiple independent calculation units based on the spatial resolution of the open source GIS data in the basic database obtained includes: selecting the smallest spatial resolution as the spatial resolution of each independent calculation unit according to the spatial resolution of the open source GIS data in the basic database, so as to divide the drainage area into multiple square grids. ,in, are the number of rows and columns of each square grid, and each square grid is regarded as an independent calculation unit.

4. The method for calculating the amount of water flowing into a river from an urban drainage system based on a GIS platform and open source data according to claim 3 is characterized in that: The runoff model of each independent calculation unit is constructed and combined with the parameter values ​​of each independent calculation unit to obtain the runoff flow and sewage flow of each independent calculation unit; including: constructing the runoff model of the independent calculation unit based on the Horton infiltration model and the nonlinear reservoir confluence model, and bringing in the parameter values ​​of the independent calculation unit to calculate the runoff flow of the independent calculation unit ; and calculate the sewage flow of independent calculation units based on population parameter values ​​and water consumption parameter values .

5. The method for calculating the amount of water flowing into a river from an urban drainage system based on a GIS platform and open source data according to claim 4 is characterized in that: The method for constructing a runoff model for an independent calculation unit based on the Horton infiltration model and the nonlinear reservoir confluence model includes: when constructing the Horton infiltration model, ignoring the change of the permeability coefficient over time and treating the permeability coefficient as a stable value; when constructing the nonlinear reservoir confluence model, ignoring the influence of evaporation and not considering the depression depth; constructing the surface water depth of the independent calculation unit based on the above Horton infiltration model and the nonlinear reservoir confluence model. h The finite difference equation of the independent calculation unit is obtained Approximate value of; Among them, the surface water of the independent calculation unit h The finite difference equation is solved by Newton-Raphson iteration method by setting the initial value of iteration and the iteration stop condition; the surface water of the independent calculation unit is obtained by Get the runoff flow of the independent calculation unit .

6. The method for calculating the amount of water flowing into a river from an urban drainage system based on a GIS platform and open source data according to claim 5 is characterized in that: The water flow in the drainage area is obtained by combining the drainage area's confluence flow with the drainage area's sewage treatment plant's treatment capacity; including: when the sub-catchment area is a diversion system, the confluence flow of the drainage area is obtained Q i The amount of water flowing into the river in the drainage area to be calculated When the subcatchment is a combined system, the amount of water flowing into the river in the drainage area to be calculated is Confluence flow with drainage area Q i and sewage treatment capacity Related: .

7. A system for calculating the amount of water flowing into rivers from urban drainage systems based on a GIS platform and open source data, characterized in that: include: An acquisition module (101) is used to acquire open source data of the drainage area to be calculated to construct a basic database, and store the basic database on a GIS platform; a processing module (102) is used to divide the drainage area to be calculated into a plurality of independent calculation units based on the spatial resolution of the open source GIS data in the basic database, and obtain parameter values ​​of each independent calculation unit according to the open source GIS data in the basic database; wherein the parameter values ​​include: rainfall parameter values, geometric parameter values, spatial parameter values, population parameter values ​​and water consumption parameter values, and the rainfall parameter values ​​include any i Rainfall data at the moment And calculate the step size , the calculation step is the rainfall data time step; the geometric parameter value includes the independent calculation unit area A and width W , and the distance between each independent calculation unit and the sewage treatment plant in the drainage area x The spatial parameter values ​​include whether the independent calculation unit is permeable and the Manning roughness coefficient obtained based on the underlying surface data , the stable permeability coefficient of the independent calculation unit obtained by the ratio of sand, silt and clay based on soil structure data And the slope obtained from DEM data The population parameter value includes the population of the independent calculation unit obtained by spatial calculation based on the spatial relationship between the population data and the independent calculation unit. r The water consumption parameter value includes the per capita water consumption of the independent calculation unit obtained based on the per capita water consumption data u and contamination coefficient γ ; Model construction module (103), used to construct the runoff model of each independent calculation unit and combine the parameter values ​​of each independent calculation unit to obtain the runoff flow and sewage flow of each independent calculation unit; calculation module (104), used to use the transfer time algorithm and combine the runoff flow and sewage flow of each independent calculation unit to obtain the confluence flow of the drainage area; including: obtaining the transfer time of the runoff flow and sewage flow of the independent calculation unit to the sewage treatment plant , transfer time Divide by the calculation step size , and round up to get ; Calculate the drainage area's confluence flow Q i , Based on the drainage area's confluence flow and combined with the drainage area's sewage treatment plant treatment capacity, the amount of water entering the river in the drainage area is obtained.

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