Rainfall runoff forecasting method, device and equipment based on improved grid convergence algorithm

Abstract

The invention provides a rainfall runoff forecasting method, device and equipment based on an improved grid convergence algorithm. The method comprises the following steps: calculating the runoff yield of each grid on the basis of a grid vertical full storage-excess infiltration combined rainfall runoff model; the grid vertical full storage-excess infiltration combined rainfall runoff model calculates runoff production in a full storage runoff production mode and a full storage runoff production mode through a vertical combined excess infiltration module and a vertical combined full storage module respectively; if the grid ground is a slope surface, calculating the convergence amount of each grid by adopting an improved grid Muskinggen convergence method based on the runoff yield of each grid; when the improved grid Muskinggen confluence method is used for calculating the surface runoff in slope confluence, the re-infiltration process is considered. Based on the scheme, by considering re-infiltration in the surface runoff confluence process, the simulated flood peak flow is effectively reduced and is closer to the actually measured flood peak, and the simulated flow hydrograph is closer to the actually measured flow hydrograph, so that compared with a traditional method, the prediction precision can be effectively improved.

Description

Technical Field

[0001] The present application relates to a precipitation runoff forecasting method, device and equipment based on an improved grid confluence algorithm, and belongs to the technical field of runoff forecasting. Background Art

[0002] Runoff refers to the water that flows along the surface or underground under the action of gravity, such as rainfall, melting ice and snow, or irrigation. As an important technical method for the rational use of water resources, runoff forecasting has important guiding significance and value in improving the flood prevention and control capabilities of river basins, the safe and economic operation efficiency of cascade hydropower stations, and the level of multi-energy complementary optimization and scheduling decision-making.

[0003] In large watersheds, the underlying surface has great spatial heterogeneity and the soil types in different areas vary greatly, resulting in significant differences in the soil's infiltration and water storage capacity. Therefore, in slope runoff, re-infiltration of surface runoff often occurs to replenish the soil water deficit in downstream areas. This is often overlooked in hydrological modeling, thus affecting the accuracy of precipitation runoff forecasts. Summary of the invention

[0004] The present application provides a precipitation runoff forecasting method, device and equipment based on an improved grid confluence algorithm to solve the problem of insufficient accuracy of precipitation runoff forecasting in the prior art.

[0005] In order to achieve the above objectives, this application provides the following technical solutions:

[0006] In a first aspect, an embodiment of the present application provides a precipitation runoff forecasting method based on an improved grid confluence algorithm, comprising:

[0007] Based on the grid vertical full storage-superinfiltration combined precipitation-runoff model, the flow generation of each grid is calculated; the grid vertical full storage-superinfiltration combined precipitation-runoff model calculates the flow generation under the two flow generation modes of full storage and superinfiltration respectively through the vertical combination superinfiltration module and the full storage module; the flow generation includes superinfiltration surface runoff, saturated surface runoff, soil flow and underground runoff;

[0008] If the grid ground is a slope, the improved grid Muskingum confluence method is used to calculate the confluence of each grid based on the flow production of each grid; the confluence includes surface flow, soil flow and underground flow; when the improved grid Muskingum confluence method calculates the surface runoff in the slope confluence, the re-infiltration process is taken into account.

[0009] Based on the above method, optionally, the calculation of the runoff of each grid based on the grid vertical storage-over-infiltration combined precipitation-runoff model includes:

[0010] The Green-Ampter infiltration formula is used to calculate the infiltration capacity of the soil in each grid:

[0011]

[0012] Where f(t) is the soil infiltration capacity at time t (mm / h); K s is the saturated hydraulic conductivity (mm / h); ψ is the soil suction at the wetting front (mm); θ s is the saturated moisture content of soil; θ t is the soil moisture content at time t; F(t) is the cumulative infiltration at time t (mm), where K s ,θ s and ψ are determined by soil type;

[0013] Based on the infiltration capacity of the soil in each grid, the excess surface runoff of the grid in each time step is calculated:

[0014]

[0015] In the formula, R ies is the excess surface runoff (mm), Δt is the time step (h), P e is the net rainfall of each grid; at this time, the amount of water infiltrating into the soil is used as the net rainfall input of the full storage module, and the flow rate is:

[0016]

[0017] Where R is the flow rate, W is M and W are the tensile water storage capacity and initial tensile water storage of the soil, respectively;

[0018] Then according to the free water storage capacity S of the soil M and initial free water storage S to calculate saturated surface runoff, soil flow and ground runoff respectively:

[0019]

[0020] R i =K i ×(R+SR ss )

[0021] R g =K g ×(R+SR ss )

[0022] In the formula, S M and S are the free water storage capacity and initial free water storage of the soil (mm), respectively. i and K g are the outflow coefficients of surface free water content on soil flow and underground runoff, R ss is the saturated surface runoff, Ri For the soil flow, R g It is underground runoff.

[0023] Based on the above method, optionally, the flow rate of each grid is calculated based on the flow rate of each grid by using an improved grid Muskingum flow rate method, including:

[0024] The surface runoff flow is calculated using the following formula:

[0025]

[0026] In the formula, and are the total surface runoff inflow (m 3 / s), including the surface runoff from the upstream grid into this grid and the surface runoff generated by the current grid; and is the surface runoff outflow of the grid; k s and x s is the runoff parameter of surface runoff; and are the re-infiltration amount of surface runoff of the grid at time t and time t+Δt respectively;

[0027] If there is over-seepage surface runoff or saturated surface runoff in the current grid during the runoff generation process, otherwise, It is expressed as:

[0028]

[0029] ΔW=WM-W 1

[0030] ΔF=f(t)Δt-P e

[0031] Where ΔW is the soil water deficit; W 1 is the tension water storage capacity of the current grid after runoff calculation; ΔF is the residual infiltration capacity; P e is the net rain that infiltrates into the soil; When the soil moisture content of each layer of the current grid is updated in turn.

[0032] Based on the above method, optionally, it also includes:

[0033] The original grid Muskingum flow method is used to calculate the subsurface flow and subsurface runoff.

[0034] Based on the above method, optionally, the determination coefficient, Nash-Sutcliffe efficiency coefficient, peak flow relative error and percentage deviation are selected as evaluation indicators of the simulation effect of a typical flow process.

[0035] Based on the above method, optionally, it also includes:

[0036] If the grid surface is non-slope, the original grid Muskingum flow method is used to calculate the flow of each grid based on the flow production of each grid.

[0037] In a second aspect, the embodiment of the present application further provides a precipitation runoff forecasting device based on an improved grid confluence algorithm, comprising:

[0038] The first calculation module is used to calculate the runoff of each grid based on the grid vertical full storage-superinfiltration combined precipitation runoff model; the grid vertical full storage-superinfiltration combined precipitation runoff model calculates the runoff under the two runoff modes of full storage and superinfiltration respectively through the vertical combination superinfiltration module and the full storage module; the runoff includes superinfiltration surface runoff, saturated surface runoff, soil flow and underground runoff;

[0039] The second calculation module is used to calculate the runoff of each grid by using the improved grid Muskingum runoff method based on the runoff of each grid if the grid ground is a slope; wherein the runoff includes surface runoff, soil runoff and underground runoff; and when the improved grid Muskingum runoff method is used to calculate the surface runoff in the slope runoff, the re-infiltration process is taken into account.

[0040] Based on the above device, optionally, when the second calculation module adopts the improved grid Muskingum confluence method to calculate the confluence of each grid, it is specifically used to:

[0041] The surface runoff flow is calculated using the following formula:

[0042]

[0043] In the formula, and are the total surface runoff inflow (m 3 / s), including the surface runoff from the upstream grid into this grid and the surface runoff generated by the current grid; and is the surface runoff outflow of the grid; k s and x s is the runoff parameter of surface runoff; and are the re-infiltration amount of surface runoff of the grid at time t and time t+Δt respectively;

[0044] If there is over-seepage surface runoff or saturated surface runoff in the current grid during the runoff generation process, otherwise, It is expressed as:

[0045]

[0046] ΔW=WM-W 1

[0047] ΔF=f(t)Δt-P e

[0048] Where ΔW is the soil water deficit; W 1 is the tension water storage capacity of the current grid after runoff calculation; ΔF is the residual infiltration capacity; P e is the net rain that infiltrates into the soil; When the soil moisture content of each layer of the current grid is updated in turn.

[0049] Based on the above device, optionally, the second calculation module is further used for:

[0050] If the grid surface is non-slope, the original grid Muskingum flow method is used to calculate the flow of each grid based on the flow production of each grid.

[0051] In a third aspect, an embodiment of the present application further provides an electronic device comprising a memory and a processor, wherein the memory stores a computer program, and when the processor calls and executes the computer program, the precipitation runoff forecasting method based on the improved grid confluence algorithm as described in any one of the first aspects is implemented.

[0052] In the precipitation runoff forecasting method, device and equipment based on the improved grid confluence algorithm provided in the present application, the method includes calculating the flow rate of each grid based on the grid vertical full storage-superinfiltration combined precipitation runoff model; the grid vertical full storage-superinfiltration combined precipitation runoff model calculates the flow rate under the two flow generation modes of full storage and superinfiltration respectively through the vertical combination superinfiltration module and the full storage module; the flow rate includes superinfiltration surface runoff, saturated surface runoff, soil flow and underground runoff; if the grid ground is a slope, based on the flow rate of each grid, the improved grid Muskingum confluence method is used to calculate the confluence of each grid; wherein the confluence includes surface flow, soil flow and underground flow; when the improved grid Muskingum confluence method calculates the surface runoff in the slope confluence, the re-infiltration process is taken into account. Based on this scheme, by considering the re-infiltration during the confluence of surface runoff, the simulated flood peak flow is effectively reduced, making it closer to the measured flood peak, and the simulated flow process line is closer to the measured flow process line. Therefore, compared with traditional methods, the prediction accuracy can be effectively improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] The accompanying drawings herein are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present application, and together with the specification are used to explain the principles of the present application. In addition, these drawings and text descriptions are not intended to limit the scope of the concept of the present application in any way, but to illustrate the concept of the present application for those skilled in the art by referring to specific embodiments.

[0054] Figure 1 A schematic flow chart of a precipitation runoff forecasting method based on an improved grid confluence algorithm provided in one embodiment of the present application;

[0055] Figure 2 This is a schematic diagram of the grid Muskingum flow routing;

[0056] Figure 3 This is the distribution map of the upper and lower soil types in the Liyuan and Wunonglong watersheds;

[0057] Figure 4 It simulates the typical water flow process in Liyuan Basin;

[0058] Figure 5 This is the simulation result of the typical water flow process in Wunonglong Basin;

[0059] Figure 6 A schematic diagram of the structure of a precipitation runoff forecasting device based on an improved grid confluence algorithm provided by an embodiment of the present application;

[0060] Figure 7 A schematic diagram of the structure of an electronic device provided for one embodiment of the present application. DETAILED DESCRIPTION

[0061] In order to make the purpose, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in combination with the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0062] Considering the problems existing in the traditional methods, the present invention provides a precipitation runoff forecasting scheme based on an improved grid confluence algorithm, which can effectively improve the prediction accuracy of precipitation runoff forecasting. The specific implementation scheme is described in a non-limiting manner through several examples or embodiments.

[0063] Some embodiments of the present application provide a precipitation runoff forecasting method based on an improved grid confluence algorithm, referring to Figure 1 , Figure 1A flow chart of a precipitation runoff forecasting method based on an improved grid confluence algorithm provided in one embodiment of the present application. In particular, the solution of this embodiment can be a software program configured in a computer or similar device. That is, the solution of this embodiment can be implemented by a software program in a device.

[0064] like Figure 1 As shown, the precipitation runoff forecasting method based on the improved grid confluence algorithm of this embodiment includes the following steps:

[0065] Step S101: Calculate the runoff of each grid based on the grid vertical storage-overinfiltration combined precipitation-runoff model.

[0066] Among them, the grid vertical storage-overinfiltration combined precipitation-runoff model calculates the runoff under the two runoff generation modes of full storage and overinfiltration through the vertical combined overinfiltration module and the storage module respectively; the runoff includes overinfiltration surface runoff, saturated surface runoff, soil flow and groundrunner.

[0067] Specifically, in this step, the grid vertical storage-overinfiltration combined precipitation-runoff model can simultaneously reflect two runoff generation modes by vertically combining overinfiltration modules and storage modules.

[0068] Furthermore, in step S101, based on the grid vertical storage-over-infiltration combined precipitation-runoff model, the flow yield of each grid is calculated, which may specifically include:

[0069] The Green-Ampter infiltration formula is used to calculate the infiltration capacity of the soil in each grid:

[0070]

[0071] Where f(t) is the soil infiltration capacity at time t (mm / h); K s is the saturated hydraulic conductivity (mm / h); ψ is the soil suction at the wetting front (mm); θ s is the saturated moisture content of soil; θ t is the soil moisture content at time t; F(t) is the cumulative infiltration at time t (mm), where K s ,θ s and ψ are determined by soil type;

[0072] Based on the infiltration capacity of the soil in each grid, the excess surface runoff of the grid in each time step is calculated:

[0073]

[0074] In the formula, R ies is the excess surface runoff (mm), Δt is the time step (h), P eis the net rainfall of each grid; at this time, the amount of water infiltrating into the soil is used as the net rainfall input of the full storage module, and the flow rate is:

[0075]

[0076] Where R is the flow rate, W is 1 and W are the tensile water storage capacity and initial tensile water storage of the soil, respectively;

[0077] Then according to the free water storage capacity S of the soil M and initial free water storage S to calculate saturated surface runoff, soil flow and ground runoff respectively:

[0078]

[0079] R i =K i ×(R+SR ss )#(6)

[0080] R g =L g ×(R+SR ss )#(7)

[0081] In the formula, S M and S are the free water storage capacity and initial free water storage of the soil (mm), respectively. i and K g are the outflow coefficients of surface free water content on soil flow and underground runoff, R ss is the saturated surface runoff, R i For the soil flow, R g It is underground runoff.

[0082] Step S102: If the grid ground is a slope, based on the flow rate of each grid, the improved grid Muskingum runoff method is used to calculate the runoff of each grid; wherein the runoff includes surface flow, soil flow and underground flow; when the improved grid Muskingum runoff method is used to calculate the surface runoff in the slope runoff, the re-infiltration process is taken into account.

[0083] Specifically, the runoff components include the superinfiltration surface runoff R ies , saturated surface runoff R ss 、Soil flow R i and underground runoff R g , where the excess surface runoff R ies and saturated surface runoff R ss The total surface runoff R s .

[0084] In the conventional scheme, the surface flow, soil flow and underground flow of the grid are as follows:

[0085]

[0086] Where: C i , C g are the recession coefficients of intersoil flow and groundwater, respectively. is the surface flow rate generated by the grid at time t (m 3 / s), is the soil flow rate generated by the grid at time t (m 3 / s), is the underground flow generated by the grid at time t (m 3 / s), A gr is the area of ​​the grid (km 2 ).

[0087] The confluence of surface runoff, subsoil flow and underground runoff all adopts the grid Muskingum confluence method. Muskingum confluence method (abbreviated as M method) is a river flow calculation method based on the channel storage equation and water balance equation. Due to its convenience and high accuracy, it has been widely used in production practice. In terms of method, it has developed from the calculation of the entire river section to the continuous calculation of each river section; in theory, it has been successfully proved that the calculation equation of M method is a difference format with second-order accuracy of the convection-diffusion equation.

[0088] Taking surface runoff as an example, refer to Figure 1 , assuming that grids a, b, and c are the adjacent upstream grids of grid e, the total inflow and outflow of surface runoff in grid a at time t are and The total surface runoff inflow of grid a at time t+Δt is At this time, the outflow of grid a is It can be expressed as:

[0089]

[0090] In the formula, k s and x s is the confluence parameter of surface runoff; the total surface runoff inflow of a grid includes the surface runoff outflow of all adjacent upstream grids plus the surface runoff generated by the current grid. Figure 2 As shown in Figure 2, the total surface runoff inflow of grid d at time t+Δt can be expressed as:

[0091]

[0092] In the formula, is the total surface runoff inflow of grid d at time t+Δt (m 3 / s), is the surface runoff outflow of grid b at time t+Δt (m 3 / s), is the surface runoff outflow of grid c at time t+Δt (m 3 / s).

[0093] Similarly, the confluence parameters of subsoil flow and groundwater runoff are k i and x i , k g and x g After the surface, soil and underground runoff of the non-river grid merges into the river grid, the river confluence also uses the grid Muskingum confluence method, and the corresponding parameter is k ch and x ch .

[0094] However, due to the large spatial heterogeneity of the underlying surface in large watersheds and the great differences in soil types in different regions, there are significant differences in the soil's infiltration capacity and water storage capacity. Therefore, in the slope runoff, re-infiltration of surface runoff often occurs to replenish the soil water deficit in the downstream area. This is often overlooked in hydrological modeling, which reduces the accuracy of precipitation runoff forecasts.

[0095] Therefore, this application proposes an improved grid Muskingum confluence algorithm to reflect the re-infiltration process of surface runoff in the slope confluence process. If the grid surface is a slope, the improved grid Muskingum confluence method is used to calculate the confluence of each grid based on the flow rate of each grid, as follows:

[0096] The surface runoff flow is calculated using the following formula:

[0097]

[0098] In the formula, and are the total surface runoff inflow (m 3 / s), including the surface runoff from the upstream grid into this grid and the surface runoff generated by the current grid; and is the surface runoff outflow of the grid; k s and x s is the runoff parameter of surface runoff; and are the re-infiltration amount of surface runoff of the grid at time t and time t+Δt respectively;

[0099] If there is over-seepage surface runoff or saturated surface runoff in the current grid during the runoff generation process, otherwise, It is expressed as:

[0100]

[0101] ΔW=WM-W 1 #(twenty one)

[0102] ΔF=f(t)Δt-P e #(twenty two)

[0103] Where ΔW is the soil water deficit; W 1 is the tension water storage capacity of the current grid after runoff calculation; ΔF is the residual infiltration capacity; P e The net rainfall infiltrating into the soil is the sum of the residual amount after deducting the interception of vegetation canopy and soil evaporation from the precipitation and the liquid water of snowmelt. When the soil moisture content of each layer of the current grid is updated in turn.

[0104] Furthermore, in some embodiments, for the confluence of subsoil flow and underground runoff, the original grid Muskingum confluence method is used to calculate the confluence of subsoil flow and underground runoff.

[0105] In addition, the above method may further include: if the grid ground is a non-slope surface, based on the flow generation of each grid, the original grid Muskingum flow confluence method is still used to calculate the confluence of each grid.

[0106] In addition, in this application, the determination coefficient (R 2 ), Nash-Sutcliffe efficiency coefficient (NSE), peak flow relative error (RE) and percentage deviation (PBIAS) are used as evaluation indicators for the simulation effect of typical flow processes. The calculation formulas for these four indicators are:

[0107]

[0108] Among them, Q i,k and Q j,k are the observed flow value and simulated flow value on the kth day (m 3 / s); and are the average values ​​of observed flow and simulated flow (m 3 / s); Q i,peak and Q j,peak are respectively the observed and simulated peak flows (m 3 / s); n is the total number of days.

[0109] Based on the above scheme, by considering the re-infiltration during the confluence of surface runoff, the simulated flood peak flow is effectively reduced, making it closer to the measured flood peak, and the simulated flow process line is closer to the measured flow process line. Therefore, compared with the traditional method, the prediction accuracy can be effectively improved.

[0110] In order to prove the effectiveness of the above scheme, an experimental verification was carried out, in which historical data of the Liyuan Basin and the Wunonglong Basin were used for simulation verification.

[0111] The distribution of soil types in the upper and lower layers of the Liyuan and Wunonglong watersheds is as follows: Figure 3 shown. Figure 3 The results show that the upper soil types in the Liyuan and Wunonglong basins are mainly sandy loam and loam, and sandy loam is mainly distributed in the upper reaches of the two basins, while loam is mainly distributed in the lower reaches of the two basins; while the lower soils in the two basins are mainly water / no value areas and clay loam. According to the hydrological grouping of each soil type, sandy loam has high infiltration potential, while loam has medium infiltration potential. Therefore, it is reasonable and necessary to consider the re-infiltration of the upstream grid during the confluence process in the hydrological simulation of the two river basins.

[0112] During the verification, a daily-scale flood process was selected from the Liyuan Basin and the Wunonglong Basin respectively. The runoff generation module of the grid vertical storage-over-infiltration combined precipitation-runoff model was used to calculate the runoff generation. The original grid Muskingum confluence algorithm and the improved Muskingum confluence method were used for simulation. The simulation results are shown in Figure 2. Figure 4 and Figure 5 shown.

[0113] Figure 4 It shows that compared with the original grid Muskingum confluence algorithm, the improved grid Muskingum confluence algorithm has a better simulation effect on the typical flood and water flow process in the Liyuan watershed, among which R 2 From 0.819 to 0.930, NSE from 0.794 to 0.930, RE from 1.53% to -0.76%, PBIAS from 0.6% to -0.04%. Figure 5 The results show that the improved grid Muskingum confluence algorithm has a better simulation effect on the typical flood and water flow process in the Wunonglong Basin. 2 It dropped from 0.944 to 0.894, but NSE increased from 0.823 to 0.891, RE dropped from 5.68% to 1.27%, and PBIAS dropped from 1.40% to 0.40%.

[0114] Through the above experiments, it can be concluded that the improved grid Muskingum confluence routing method proposed in this application significantly improves the simulation effect of the typical flood and receding process in the two river basins. By considering the re-infiltration during the confluence of surface runoff, the simulated flood peak flow is effectively reduced, making it closer to the measured flood peak, and the simulated flow process line is closer to the measured flow process line. Especially for precipitation events with the precipitation center located upstream, this method shows obvious advantages; while for precipitation events with the precipitation center located downstream, the advantages of this method are relatively weak.

[0115] In addition, the embodiment of the present application provides a precipitation runoff forecasting device based on an improved grid confluence algorithm, referring to Figure 6 , the precipitation runoff forecasting device based on the improved grid confluence algorithm includes:

[0116] The first calculation module 61 is used to calculate the runoff of each grid based on the grid vertical full storage-super infiltration combined precipitation runoff model; the grid vertical full storage-super infiltration combined precipitation runoff model calculates the runoff under the two runoff modes of full storage and super infiltration respectively through the vertical combination super infiltration module and the full storage module; the runoff includes super infiltration surface runoff, saturated surface runoff, soil flow and underground runoff;

[0117] The second calculation module 62 is used to calculate the runoff of each grid using an improved grid Muskingum runoff method based on the runoff of each grid if the grid ground is a slope; wherein the runoff includes surface runoff, soil runoff and underground runoff; and when the improved grid Muskingum runoff method is used to calculate the surface runoff in the slope runoff, the re-infiltration process is taken into account.

[0118] Based on the above device, optionally, when the second calculation module 62 uses the improved grid Muskingum confluence method to calculate the confluence of each grid, it is specifically used to:

[0119] The surface runoff flow is calculated using the following formula:

[0120]

[0121] In the formula, and are the total surface runoff inflow (m 3 / s), including the surface runoff from the upstream grid into this grid and the surface runoff generated by the current grid; and is the surface runoff outflow of the grid; k s and x s is the runoff parameter of surface runoff; and are the re-infiltration amount of surface runoff of the grid at time t and time t+Δt respectively;

[0122] If there is over-seepage surface runoff or saturated surface runoff in the current grid during the runoff generation process, otherwise, It is expressed as:

[0123]

[0124] ΔW=WM-W 1

[0125] ΔF=f(t)Δt-P e

[0126] Where ΔW is the soil water deficit; W 1 is the tension water storage capacity of the current grid after runoff calculation; ΔF is the residual infiltration capacity; P e is the net rain that infiltrates into the soil; When the soil moisture content of each layer of the current grid is updated in turn.

[0127] Optionally, the second calculation module 62 is further used for:

[0128] If the grid surface is non-slope, the original grid Muskingum flow method is used to calculate the flow of each grid based on the flow production of each grid.

[0129] Among them, regarding the specific implementation methods of each module of the above-mentioned precipitation runoff forecasting device based on the improved grid confluence algorithm, reference can be made to the corresponding contents in the aforementioned method embodiments, which will not be repeated here.

[0130] In addition, an embodiment of the present application provides an electronic device, such as Figure 7 As shown, the electronic device includes a memory 71 and a processor 72; wherein the memory 71 stores a computer program, and when the processor 72 calls and executes the computer program, the precipitation runoff forecasting method based on the improved grid confluence algorithm in any of the above embodiments is implemented.

[0131] The electronic device may be a computer or a controller, etc.

[0132] 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.

[0133] It should be noted that, in the description of the present invention, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of the present invention, unless otherwise specified, the meaning of "plurality" refers to at least two.

[0134] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code that includes 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 not be performed in 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 belong.

[0135] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0136] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0137] In addition, each functional unit in each embodiment of the present invention may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium. The above-mentioned storage medium may be a read-only memory, a disk or an optical disk, etc.

[0138] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0139] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A precipitation runoff forecasting method based on an improved grid confluence algorithm, characterized in that: include: Based on the grid vertical storage-over-infiltration combined precipitation-runoff model, the flow yield of each grid is calculated; The grid vertical full storage-over-infiltration combined precipitation-runoff model calculates the runoff under the two runoff generation modes of full storage and over-infiltration respectively through the vertical combined over-infiltration module and the full storage module; the runoff includes over-infiltration surface runoff, saturated surface runoff, soil flow and underground runoff; If the grid ground is a slope, the improved grid Muskingum confluence method is used to calculate the confluence of each grid based on the flow production of each grid; the confluence includes surface flow, soil flow and underground flow; when the improved grid Muskingum confluence method calculates the surface runoff in the slope confluence, the re-infiltration process is taken into account.

2. The method according to claim 1, characterized in that The flow generation of each grid is calculated based on the grid vertical storage-over-infiltration combined precipitation-runoff model, including: The Green-Ampter infiltration formula is used to calculate the infiltration capacity of the soil in each grid: Where f(t) is the soil infiltration capacity at time t (mm / h); K s is the saturated hydraulic conductivity (mm / h); ψ is the soil suction at the wetting front (mm); θ s is the saturated moisture content of soil; θ t is the soil moisture content at time t; F(t) is the cumulative infiltration at time t (mm), where K s ,θ s and ψ are determined by soil type; Based on the infiltration capacity of the soil in each grid, the excess surface runoff of the grid in each time step is calculated: In the formula, R ies is the excess surface runoff (mm), Δt is the time step (h), P e is the net rainfall of each grid; at this time, the amount of water infiltrating into the soil is used as the net rainfall input of the full storage module, and the flow rate is: Where R is the flow rate, W is M and W are the tensile water storage capacity and initial tensile water storage of the soil, respectively; Then according to the free water storage capacity S of the soil M and initial free water storage S to calculate saturated surface runoff, soil flow and ground runoff respectively: R i =K i ×(R+S-R ss ) R g =K g ×(R+S-R ss ) In the formula, S M and S are the free water storage capacity and initial free water storage of the soil (mm), respectively. i and K g are the outflow coefficients of surface free water content on soil flow and underground runoff, R ss is the saturated surface runoff, R i For the soil flow, R g It is underground runoff.

3. The method according to claim 1, characterized in that The improved grid Muskingum confluence method is used to calculate the confluence of each grid based on the flow generation of each grid, including: The surface runoff flow is calculated using the following formula: In the formula, and are the total surface runoff inflow (m 3 / s), including the surface runoff from the upstream grid into this grid and the surface runoff generated by the current grid; and is the surface runoff outflow of the grid; k s and x s is the runoff parameter of surface runoff; and are the re-infiltration amount of surface runoff of the grid at time t and time t+Δt respectively; If there is over-seepage surface runoff or saturated surface runoff in the current grid during the runoff generation process, otherwise, It is expressed as: ΔW=WM-W1 ΔF=f(t)Δt-P e Where ΔW is the soil water deficit; W1 is the tension water storage of the current grid after runoff calculation; ΔF is the residual infiltration capacity; P e is the net rain that infiltrates into the soil; When the soil moisture content of each layer of the current grid is updated in turn.

4. The method according to claim 3, characterized in that Also includes: The original grid Muskingum flow method is used to calculate the subsurface flow and subsurface runoff.

5. The method according to claim 1, characterized in that The determination coefficient, Nash-Sutcli ffe efficiency coefficient, peak flow relative error and percentage deviation were selected as evaluation indicators of the simulation effect of typical flow processes.

6. The method according to claim 1, characterized in that Also includes: If the grid ground is non-slope, the original grid Muskingum flow method is used to calculate the flow of each grid based on the flow production of each grid.

7. A precipitation runoff forecasting device based on an improved grid confluence algorithm, characterized in that: include: The first calculation module is used to calculate the flow rate of each grid based on the grid vertical storage-over-infiltration combined precipitation-runoff model; The grid vertical full storage-over-infiltration combined precipitation-runoff model calculates the runoff under the two runoff generation modes of full storage and over-infiltration respectively through the vertical combined over-infiltration module and the full storage module; the runoff includes over-infiltration surface runoff, saturated surface runoff, soil flow and underground runoff; The second calculation module is used to calculate the runoff of each grid by using the improved grid Muskingum runoff method based on the runoff of each grid if the grid ground is a slope; wherein the runoff includes surface runoff, soil runoff and underground runoff; and when the improved grid Muskingum runoff method is used to calculate the surface runoff in the slope runoff, the re-infiltration process is taken into account.

8. The device according to claim 7, characterized in that When the improved grid Muskingum confluence method is used to calculate the confluence of each grid, the second calculation module is specifically used to: The surface runoff flow is calculated using the following formula: In the formula, and are the total surface runoff inflow (m 3 / s), including the surface runoff from the upstream grid into this grid and the surface runoff generated by the current grid; and is the surface runoff outflow of the grid; k s and x s is the runoff parameter of surface runoff; and are the re-infiltration amount of surface runoff of the grid at time t and time t+Δt respectively; If there is over-seepage surface runoff or saturated surface runoff in the current grid during the runoff generation process, otherwise, It is expressed as: ΔW=WM-W1 ΔF=f(t)Δt-P e Where ΔW is the soil water deficit; W1 is the tension water storage of the current grid after runoff calculation; ΔF is the residual infiltration capacity; P e is the net rain that infiltrates into the soil; When the soil moisture content of each layer of the current grid is updated in turn.

9. The device according to claim 7, characterized in that The second calculation module is also used for: If the grid surface is non-slope, the original grid Muskingum flow method is used to calculate the flow of each grid based on the flow production of each grid.

10. An electronic device, characterized in that: It comprises a memory and a processor, wherein the memory stores a computer program, and when the processor calls and executes the computer program, the precipitation runoff forecasting method based on the improved grid confluence algorithm as described in any one of claims 1 to 6 is implemented.

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