Method and device for simulating urban rainfall-runoff relationship based on sensitivity function

Abstract

This invention provides a method and device for simulating the relationship between urban rainfall and runoff based on a sensitivity function. The method comprises: Step 1: determining the area of ​​different underlying surface types in a catchment area and generalizing the runoff paths; Step 2: constructing a runoff calculation formula for the catchment area. This method considers the impervious area ratio and spatial distribution characteristics of the catchment area in the calculation, providing support for rainfall-runoff calculations under different urban development scales or sponge construction scales.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of urban hydrological simulation, and in particular to a method and device for simulating the relationship between urban rainfall and runoff based on a sensitivity function. Background Art

[0002] The world is currently in a rapid urbanization process, and the average annual growth rate of urban land area worldwide is rapid. The expansion of urban impervious surfaces in the process of urbanization has seriously affected the natural hydrological cycle of urban watersheds, including the infiltration process of rainfall and the surface runoff process, further causing water problems such as frequent urban flooding and reduced base flow of urban rivers. Faced with this situation, relevant methods have adopted stormwater management measures to reduce the negative impact of the hydrological effects of urbanization. However, the runoff patterns of urban catchment areas transformed by these measures are complex, and how to reasonably simulate rainfall runoff has become a new topic. Therefore, the development of a method and equipment for simulating the relationship between urban rainfall and runoff based on sensitivity functions can effectively overcome the defects in the above-mentioned related technologies, which has become a technical problem that needs to be solved urgently in the industry. Summary of the Invention

[0003] In response to the above-mentioned problems existing in the prior art, an embodiment of the present invention provides a method and device for simulating the relationship between urban rainfall and runoff based on a sensitivity function.

[0004] In the first aspect, an embodiment of the present invention provides a method for simulating the relationship between urban rainfall and runoff based on a sensitivity function, comprising: step 1, determining the area of ​​different underlying surface types in the catchment area and generalizing the runoff path; step 2, constructing a runoff calculation formula for the catchment area: based on the runoff coefficient R-impervious surface area I sensitivity S R-I Function, the expression is:

[0005]

[0006] Among them, a, b, and c are fitting parameters related to the underlying surface conditions; P represents the total rainfall of the rainfall event; P 0.5h represents the maximum rainfall in 0.5 hours. For the receiving permeable surface RPA-disconnected impervious surface DIA system, the corresponding surface runoff coefficient α is calculated according to formula (2):

[0007]

[0008] Where P is the total rainfall of the rainfall event; I a,imp S is the storage capacity of impervious surface depression; R-I is the runoff coefficient-impervious surface area sensitivity function; IR is the system impervious area ratio; Substituting (1) into (2), the surface runoff of the receiving permeable surface RPA-disconnected impervious surface DIA system is calculated by (3):

[0009]

[0010] Among them, IR is the area ratio of disconnected impervious surface in the receiving permeable surface RPA-disconnected impervious surface DIA system. When calculating the natural pervious surface PA subsystem, I a,imp and IR takes the value of 0.

[0011] On the basis of the contents of the above-mentioned method embodiment, the urban rainfall-runoff relationship simulation method based on sensitivity function provided in the embodiment of the present invention, the step 1 specifically includes: according to the distribution characteristics of the impervious surface of the underlying surface after the construction of the sponge city, the urban catchment area is generalized into three parts: the receiving permeable surface RPA-disconnected impervious surface DIA system, the natural permeable surface PA and the connected impervious surface DCIA, and the areas A1, A2, A3 of the three parts, as well as the impervious area ratio IR in the receiving permeable surface RPA-disconnected impervious surface DIA system are determined.

[0012] Based on the content of the above method embodiment, the urban rainfall-runoff relationship simulation method based on sensitivity function provided in the embodiment of the present invention is a,imp After IR is 0, it also includes: the rainfall AR in the previous three days 3d There is a threshold x. There is a significant difference in runoff coefficients between two groups of rainfall events with values ​​greater than or less than the threshold x. The initial soil moisture levels of the rainfall events are divided, and different soil moisture levels correspond to different values ​​of the fitting parameters b and c. The average runoff coefficient of the catchment area is calculated using the area-weighted method based on the runoff coefficients of the receiving permeable surface RPA-disconnected impervious surface DIA system, the natural permeable surface PA, and the connected impervious surface DCIA:

[0013]

[0014] Among them, A1, A2, and A3 are the areas of the receiving permeable surface RPA-disconnected impermeable surface DIA system, the natural permeable surface PA, and the connected impermeable surface DCIA in the catchment area respectively; R RPA-DIA and R PA are the surface runoff of the receiving permeable surface RPA-disconnected impervious surface DIA system and the natural permeable surface PA in the catchment area; P is the total rainfall of the rainfall event; I DCIA It indicates the amount of depression storage loss of the connected impervious surface.

[0015] Based on the contents of the above method embodiments, the urban rainfall-runoff relationship simulation method based on the sensitivity function provided in the embodiments of the present invention has the fitting parameter a representing the minimum value of RI sensitivity, which is the difference between the runoff coefficients of the permeable surface and the impervious surface under extreme rainfall conditions and is proportional to the infiltration capacity of the permeable surface; the fitting parameter b represents the impact of changes in the total rainfall amount on the RI sensitivity, which is related to the rate at which the infiltration capacity of the permeable surface decays with increasing soil moisture; and the fitting parameter c reflects the impact of changes in rainfall intensity on the RI sensitivity, which is related to the change in the relative infiltration capacity of the permeable surface with rainfall intensity.

[0016] Based on the contents of the above-mentioned method embodiments, the urban rainfall-runoff relationship simulation method based on sensitivity function provided in the embodiments of the present invention includes: when calculating the runoff of the catchment area, the underlying surface is divided into three parts: the receiving permeable surface RPA-disconnected impervious surface DIA system, the natural permeable surface PA and the connected impervious surface DCIA according to the infiltration capacity of the underlying surface and the runoff generation characteristics, the runoff is calculated separately, and the total surface runoff of the catchment area is calculated according to the area weighted method.

[0017] Based on the content of the above method embodiment, the urban rainfall-runoff relationship simulation method based on sensitivity function provided in the embodiment of the present invention includes: when calculating the runoff of the receiving permeable surface RPA-disconnected impermeable surface DIA system and the natural permeable surface PA, according to the rainfall AR in the previous three days 3d The threshold x is used to divide the initial soil moisture of all rainfall events, and the values ​​of the fitting parameters b and c are calculated to reflect the influence of the initial soil moisture on runoff generation.

[0018] In a second aspect, an embodiment of the present invention provides an urban rainfall-runoff relationship simulation device based on a sensitivity function, comprising: a first main module for implementing step 1, determining the area of ​​different underlying surface types in the catchment area and generalizing the runoff path; a second main module for implementing step 2, constructing a catchment runoff calculation formula: based on the runoff coefficient R-impervious surface area I sensitivity S R-I Function, the expression is:

[0019]

[0020] Among them, a, b, and c are fitting parameters related to the underlying surface conditions; P represents the total rainfall of the rainfall event; P 0.5h represents the maximum rainfall in 0.5 hours. For the receiving permeable surface RPA-disconnected impervious surface DIA system, the corresponding surface runoff coefficient α is calculated according to formula (2):

[0021]

[0022] Where P is the total rainfall of the rainfall event; I a,impS is the storage capacity of impervious surface depression; R-I is the runoff coefficient-impervious surface area sensitivity function; IR is the system impervious area ratio; Substituting (1) into (2), the surface runoff of the receiving permeable surface RPA-disconnected impervious surface DIA system is calculated by (3):

[0023]

[0024] Among them, IR is the area ratio of disconnected impervious surface in the receiving permeable surface RPA-disconnected impervious surface DIA system. When calculating the natural pervious surface PA subsystem, I a,imp and IR takes the value of 0.

[0025] In a third aspect, an embodiment of the present invention provides an electronic device, including:

[0026] at least one processor; and

[0027] at least one memory communicatively coupled to the processor, wherein:

[0028] The memory stores program instructions that can be executed by the processor, and the processor calls the program instructions to execute the urban rainfall-runoff relationship simulation method based on sensitivity function provided by any one of the various implementation methods of the first aspect.

[0029] In a fourth aspect, an embodiment of the present invention provides a non-transitory computer-readable storage medium, which stores computer instructions, and the computer instructions enable a computer to execute the urban rainfall-runoff relationship simulation method based on sensitivity function provided by any one of the various implementation methods of the first aspect.

[0030] The urban rainfall-runoff relationship simulation method and equipment based on sensitivity function provided in the embodiment of the present invention take into account the impervious area ratio and spatial distribution characteristics of the catchment area in the calculation, providing support for rainfall-runoff calculation under different urban development scales or sponge construction scales. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are 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.

[0032] Figure 1 A flow chart of a method for simulating the relationship between urban rainfall and runoff based on a sensitivity function provided by an embodiment of the present invention;

[0033] Figure 2A schematic diagram of the structure of an urban rainfall-runoff relationship simulation device based on a sensitivity function provided by an embodiment of the present invention;

[0034] Figure 3 A schematic diagram of the physical structure of an electronic device provided by an embodiment of the present invention;

[0035] Figure 4 A schematic diagram of the location of the application area provided by an embodiment of the present invention;

[0036] Figure 5 A schematic diagram of DCIA event screening results provided by an embodiment of the present invention;

[0037] Figure 6 Schematic diagram of the fitting effect of the runoff coefficient calculated based on the runoff coefficient-impervious surface area sensitivity function and the calculation results of the measured rainfall runoff data provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. In addition, the technical features in the various embodiments or single embodiments provided by the present invention can be arbitrarily combined with each other to form a feasible technical solution. This combination is not restricted by the sequence of steps and / or structural composition mode, but must be based on the ability of ordinary technicians in this field to implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0039] In traditional urban development models, runoff from almost all impervious urban surfaces is discharged directly into the urban drainage system (e.g., stormwater pipe networks, hardened channels, etc.). The runoff generation processes of urban impervious surfaces and permeable surfaces (e.g., urban green spaces, bare land, etc.) are largely independent and mutually unaffected. However, in sponge-based urban development, the deployment of numerous headwater sponge facilities disrupts the hydraulic connection between urban impervious surfaces and the urban drainage system. Impervious surface runoff thus affects the runoff generation processes of permeable sponge facilities, which in turn affects the effectiveness of permeable surfaces in controlling impervious surface runoff. In this scenario, runoff from impervious and permeable surfaces can no longer be considered independent, and the hydrological effects of urban impervious surfaces are therefore more complex. When simulating urban rainfall runoff, the sub-catchment area is divided into multiple independent parts according to the underlying surface infiltration and runoff characteristics. A calculation method based on the runoff coefficient-impervious surface area sensitivity function is proposed, taking into account the impervious area ratio of the catchment area and its spatial distribution characteristics, providing a new method for rainfall runoff calculation under different urban development scales or sponge construction scales. Based on this idea, the embodiment of the present invention provides a method for simulating the relationship between urban rainfall and runoff based on the sensitivity function, see Figure 1 The method includes: step 1, determining the area of ​​different underlying surface types in the catchment area and generalizing the runoff path; step 2, constructing a runoff calculation formula for the catchment area: based on the runoff coefficient R-impervious surface area I sensitivity S R-I Function, the expression is:

[0040]

[0041] Among them, a, b, and c are fitting parameters related to the underlying surface conditions; P represents the total rainfall of the rainfall event; P 0.5h represents the maximum rainfall in 0.5 hours. For the receiving permeable surface RPA-disconnected impervious surface DIA system, the corresponding surface runoff coefficient α is calculated according to formula (2):

[0042]

[0043] Where P is the total rainfall of the rainfall event; I a,imp S is the storage capacity of impervious surface depression; R-I is the runoff coefficient-impervious surface area sensitivity function; IR is the system impervious area ratio; Substituting (1) into (2), the surface runoff of the receiving permeable surface RPA-disconnected impervious surface DIA system is calculated by (3):

[0044]

[0045] Among them, IR is the area ratio of disconnected impervious surface in the receiving permeable surface RPA-disconnected impervious surface DIA system. When calculating the natural pervious surface PA subsystem, I a,impand IR takes the value of 0.

[0046] Based on the content of the above method embodiment, as an optional embodiment, the urban rainfall-runoff relationship simulation method based on sensitivity function provided in the embodiment of the present invention, the step 1 specifically includes: according to the distribution characteristics of the impervious surface of the underlying surface after the construction of the sponge city, the urban catchment area is generalized into three parts: the receiving permeable surface RPA-disconnected impervious surface DIA system, the natural permeable surface PA and the connected impervious surface DCIA, and the areas A1, A2, A3 of the three parts, as well as the impervious area ratio IR in the receiving permeable surface RPA-disconnected impervious surface DIA system are determined.

[0047] Based on the content of the above method embodiment, as an optional embodiment, the urban rainfall-runoff relationship simulation method based on sensitivity function provided in the embodiment of the present invention is a,imp After IR is 0, it also includes: the rainfall AR in the previous three days 3d There is a threshold x. There is a significant difference in runoff coefficients between two groups of rainfall events with values ​​greater than or less than the threshold x. The initial soil moisture levels of the rainfall events are divided, and different soil moisture levels correspond to different values ​​of the fitting parameters b and c. The average runoff coefficient of the catchment area is calculated using the area-weighted method based on the runoff coefficients of the receiving permeable surface RPA-disconnected impervious surface DIA system, the natural permeable surface PA, and the connected impervious surface DCIA:

[0048]

[0049] Among them, A1, A2, and A3 are the areas of the receiving permeable surface RPA-disconnected impermeable surface DIA system, the natural permeable surface PA, and the connected impermeable surface DCIA in the catchment area respectively; R RPA-DIA and R PA are the surface runoff of the receiving permeable surface RPA-disconnected impervious surface DIA system and the natural permeable surface PA in the catchment area; P is the total rainfall of the rainfall event; I DCIA It indicates the amount of depression storage loss of the connected impervious surface.

[0050] Based on the content of the above method embodiment, as an optional embodiment, the urban rainfall-runoff relationship simulation method based on the sensitivity function provided in the embodiment of the present invention, the fitting parameter a represents the minimum value of RI sensitivity, which is the difference between the runoff coefficients of the permeable surface and the impervious surface under extreme rainfall conditions, and is proportional to the infiltration capacity of the permeable surface; the fitting parameter b represents the impact of changes in the total rainfall amount on the RI sensitivity, which is related to the rate at which the infiltration capacity of the permeable surface decays with increasing soil moisture; the fitting parameter c reflects the impact of changes in rainfall intensity on the RI sensitivity, and is related to the change in the relative infiltration capacity of the permeable surface with rainfall intensity.

[0051] Based on the content of the above method embodiment, as an optional embodiment, the urban rainfall-runoff relationship simulation method based on sensitivity function provided in the embodiment of the present invention includes: when calculating the runoff of the catchment area, the underlying surface is divided into three parts according to the infiltration capacity of the underlying surface and the runoff generation characteristics: the receiving permeable surface RPA-disconnected impervious surface DIA system, the natural permeable surface PA and the connected impervious surface DCIA, the runoff is calculated for each part, and the total surface runoff of the catchment area is calculated according to the area weighted method.

[0052] Based on the content of the above method embodiment, as an optional embodiment, the urban rainfall-runoff relationship simulation method based on sensitivity function provided in the embodiment of the present invention includes: when calculating the runoff of the receiving permeable surface RPA-disconnected impermeable surface DIA system and the natural permeable surface PA, according to the rainfall AR in the previous three days 3d The threshold x is used to divide the initial soil moisture of all rainfall events, and the values ​​of the fitting parameters b and c are calculated to reflect the influence of the initial soil moisture on runoff generation.

[0053] The urban rainfall-runoff relationship simulation method based on sensitivity function provided in an embodiment of the present invention takes into account the impervious area ratio and spatial distribution characteristics of the catchment area in the calculation, providing support for rainfall-runoff calculation under different urban development scales or sponge construction scales.

[0054] In another embodiment, a typical sponge community in a city is used as the research object ( Figure 4 ), based on the duration rainfall runoff data in the study area, the rainfall runoff calculation method based on runoff coefficient-impervious surface area sensitivity was calibrated and verified.

[0055] Step 1: Calculate the area of ​​different underlying surface types in the subcatchment area:

[0056] Table 1 shows the underlying surface composition of the two sub-catchments C1 and C2 within the community, as determined through remote sensing image analysis. The sponge facilities correspond to the receiving permeable surface (RPA), while the impervious surface includes the connected impervious surface (DCIA) and the disconnected impervious surface (DIA). To obtain the corresponding areas of the RPA-DIA system, natural pervious surface, and DCIA required for calculations, the area of ​​the connected impervious surface (DCIA) was also determined.

[0057] Table 1 Composition of underlying surface in subcatchment area of ​​study area

[0058]

[0059] *Indicates the area ratio of underlying surface type to subcatchment area.

[0060] Step 2: Determine the DCIA area of ​​the study area: In this case, the rainfall-runoff analysis method is used to determine the DCIA area of ​​the catchment area.

[0061] The rainfall-runoff sequence is divided into rainfall events to obtain a rainfall-runoff dataset for each rainfall event. The basis for rainfall event division is that the total rainfall of each rainfall event is greater than 2 mm and the interval between adjacent rainfall events should be greater than 6 hours without rainfall.

[0062] Remove outlier data points. Plot the rainfall-runoff data points with rainfall as the X-axis and runoff as the Y-axis and perform ordinary least squares regression to calculate the standardized residual for each rainfall-runoff data point:

[0063]

[0064] Among them, SE i represents the standardized residual of the i-th rainfall-runoff data point; e i represents the residual of the ith data point; MSE represents the average of the sum of squared residuals of all data points.

[0065] The filtered data points are re-performed with ordinary least squares regression, and the weight of each data point is calculated using formula (6):

[0066]

[0067] Among them, w i represents the weight of the i-th data point.

[0068] After that, weighted least squares regression is performed based on the weights of the data points, and the residuals of the weighted least squares regression of each data point are calculated. The residual threshold for screening DCIA event data points is then determined according to the following formula:

[0069] e DCIA =max(2·SE,1mm) (7)

[0070] Where SE represents the standard error of regression. Based on the residuals of the weighted least squares regression calculated above, the residuals greater than e DCIA Data points with the same or similar events were classified as non-DCIA events and excluded.

[0071] Repeat the calculation and elimination of the remaining data points in order until the residuals of all data points are less than e DCIA The slope of the regression formula is the ratio of DCIA to the catchment area, and the intercept of the regression line on the X-axis is the impervious surface depression depth.

[0072] According to the above process, after removing outliers, weighted least squares regression and DCIA event screening are performed, and the results are as follows Figure 5 As shown. Figure 5The results show that the DCIA ratio (the ratio of DCIA to the total area of ​​the catchment) of sub-catchments C1 and C2 are 0.04 and 0.07 respectively, and the impervious surface depression storage are 4.8 mm and 3.1 mm respectively.

[0073] Step 3: Construction of surface runoff calculation formula for the catchment area and calibration and verification of empirical parameters:

[0074] Based on the DCIA and impervious surface depression storage calculated in step 2, combined with the area of ​​sponge facilities, natural pervious surfaces, and total impervious surfaces, the surface runoff coefficients of subcatchments C1 and C2 are expressed as follows according to the area weighting method:

[0075] α C1 =[0.04·(P-4.8)+0.88·R RPA-DIA,C1 +0.08·R PA,C1 ] / P (8)

[0076] α C2 =[0.07·(P-3.1)+0.89·R RPA-DIA,C2 +0.04·R PA,C2 ] / P (9)

[0077] Among them, α C1 represents the surface runoff coefficient of subcatchment C1; α C2 represents the surface runoff coefficient of subcatchment C2; P represents the total rainfall of the rainfall event (mm); R RPA-DIA,C1 and R RPA-DIA,C2 are the surface runoff of the RPA-DIA system in subcatchment C1 and subcatchment C2 respectively; R PA,C1 and R PA,C2 Represent the runoff of the natural permeable surface in subcatchment C1 and subcatchment C2 respectively. RPA-DIA,C1 、R RPA-DIA,C2 、R PA,C1 and R PA,C2 The empirical formula (10) is used for calculation.

[0078]

[0079] Where IR is the ratio of the impervious surface area of ​​the RPA-DIA system.

[0080] Assuming that the underlying surface conditions of the sponge facilities in the two sub-catchments C1 and C2, such as the overall engineering structure, filler texture, slope, confluence length, and initial soil moisture of each rainfall, are similar, the same set of empirical parameters are used to calculate the RRPA-DIA of the two sub-catchments. Similarly, assuming that the underlying surface conditions of the natural permeable surfaces in the two sub-catchments, such as the overall soil texture, slope, confluence length, and initial soil moisture of each rainfall, are similar, the same set of empirical parameters are used to calculate the RPA of the two sub-catchments.

[0081] Rainfall events were grouped using a threshold of 80 mm rainfall over the first three days. The runoff coefficients of the two groups were tested using a Mann-Whitney test. The results showed a significant difference in the runoff coefficients between the two groups at the P = 0.001 level. Based on this, the initial soil moisture levels of all rainfall events were divided using a threshold of 80 mm rainfall over the first three days. The empirical parameter values ​​for rainfall events within the same initial soil moisture level were calculated without considering the influence of initial soil moisture. The runoff of each subcatchment (R RPA-DIA and R PA ) is expressed as formula (11) to formula (14):

[0082]

[0083]

[0084]

[0085]

[0086] Among them, AR 3d represents the rainfall in the previous three days; f represents the empirically fitted parameters a, b, c, as well as the impervious area ratio IR, the total rainfall P, and the maximum 0.5-hour rainfall P 0.5h The function formula for calculating the surface runoff coefficient of the RPA-DIA system is as shown in formula (15).

[0087]

[0088] All rainfall events were sorted according to the size of the surface runoff coefficient. After sorting, the rainfall events in odd and even rows were selected as the calibration and verification events, respectively. Finally, a total of 87 calibration events were obtained for the two sub-catchments, with an average surface runoff coefficient of 0.048; a total of 88 verification events were obtained, with an average surface runoff coefficient of 0.052.

[0089] The empirical parameter calibration is carried out using genetic algorithm to determine the coefficient R 2 As an indicator for evaluating the accuracy of the response function prediction value, the calculation formula includes formula (16), with max(R 2) as the objective function of the genetic algorithm:

[0090]

[0091] Among them, Y i represents the runoff coefficient of the ith measurement; X i = represents the runoff coefficient of the ith simulation; Y represents the average value of the measured runoff coefficient. The calibration range of parameters a1 and a2 is 0 to 0.5; the calibration range of parameters b1, b2, b3, and b4 is 0 to 200; and the calibration range of parameters c1, c2, c3, and c4 is 0 to 20. Running the genetic algorithm, the optimal calibration result is finally obtained as follows Figure 6 As shown in part (a) of the figure, the parameter calibration results are shown in Table 2; the verification results based on the calibrated parameters are shown in Figure 6 As shown in part (b) of .

[0092] Table 2 Empirical parameter calibration results

[0093]

[0094] This example specifically explains the calculation steps of the urban rainfall runoff calculation method based on the runoff coefficient-impervious surface area sensitivity function and verifies the applicability of the method.

[0095] The implementation basis of each embodiment of the present invention is to implement it through programmed processing by a device with processor function. Therefore, in engineering practice, the technical solutions and functions of each embodiment of the present invention can be encapsulated into various modules. Based on this reality, on the basis of the above embodiments, an embodiment of the present invention provides an urban rainfall-runoff relationship simulation device based on a sensitivity function, which is used to execute the urban rainfall-runoff relationship simulation method based on a sensitivity function in the above method embodiment. Figure 2 The device includes: a first main module for implementing step 1, determining the area of ​​different underlying surface types in the catchment area and generalizing the runoff path; a second main module for implementing step 2, constructing a runoff calculation formula for the catchment area: based on the runoff coefficient R-impervious surface area I sensitivity S R-I Function, the expression is:

[0096]

[0097] Among them, a, b, and c are fitting parameters related to the underlying surface conditions; P represents the total rainfall of the rainfall event; P 0.5h represents the maximum rainfall in 0.5 hours. For the receiving permeable surface RPA-disconnected impervious surface DIA system, the corresponding surface runoff coefficient α is calculated according to formula (2):

[0098]

[0099] Where P is the total rainfall of the rainfall event; I a,imp S is the storage capacity of impervious surface depression; R-I is the runoff coefficient-impervious surface area sensitivity function; IR is the system impervious area ratio; Substituting (1) into (2), the surface runoff of the receiving permeable surface RPA-disconnected impervious surface DIA system is calculated by (3):

[0100]

[0101] Among them, IR is the area ratio of disconnected impervious surface in the receiving permeable surface RPA-disconnected impervious surface DIA system. When calculating the natural pervious surface PA subsystem, I a,imp and IR takes the value of 0.

[0102] The urban rainfall-runoff relationship simulation device based on sensitivity function provided by the embodiment of the present invention adopts Figure 2 Several modules in the system consider the impervious area ratio and spatial distribution characteristics of the catchment area in the calculation, providing support for rainfall runoff calculation under different urban development scales or sponge construction scales.

[0103] It should be noted that the device in the device embodiment provided by the present invention can be used to implement the method in the above-mentioned method embodiment as well as the method in other method embodiments provided by the present invention. The only difference is that the corresponding functional modules are set. The principle is basically the same as the principle of the above-mentioned device embodiment provided by the present invention. As long as those skilled in the art refer to the specific technical solutions in other method embodiments on the basis of the above-mentioned device embodiment, obtain the corresponding technical means and the technical solutions composed of these technical means by combining technical features, and ensure the practicality of the technical solutions, they can improve the device in the above-mentioned device embodiment to obtain the corresponding device class embodiment, thereby obtaining the corresponding device class embodiment for implementing the methods in other method class embodiments. For example:

[0104] Based on the content of the above-mentioned device embodiment, as an optional embodiment, the urban rainfall-runoff relationship simulation device based on sensitivity function provided in the embodiment of the present invention further includes: a first submodule, which is used to implement the step 1, specifically including: according to the distribution characteristics of the impervious surface of the underlying surface after the construction of the sponge city, the urban catchment area is generalized into three parts: the receiving permeable surface RPA-disconnected impervious surface DIA system, the natural permeable surface PA and the connected impervious surface DCIA, and the areas A1, A2, A3 of the three parts, as well as the impervious area ratio IR in the receiving permeable surface RPA-disconnected impervious surface DIA system are determined.

[0105] Based on the content of the above device embodiment, as an optional embodiment, the urban rainfall-runoff relationship simulation device based on sensitivity function provided in the embodiment of the present invention further includes: a second submodule for implementing the above I a,imp After IR is 0, it also includes: the rainfall AR in the previous three days 3d There is a threshold x. There is a significant difference in runoff coefficients between two groups of rainfall events with values ​​greater than or less than the threshold x. The initial soil moisture levels of the rainfall events are divided, and different soil moisture levels correspond to different values ​​of the fitting parameters b and c. The average runoff coefficient of the catchment area is calculated using the area-weighted method based on the runoff coefficients of the receiving permeable surface RPA-disconnected impervious surface DIA system, the natural permeable surface PA, and the connected impervious surface DCIA:

[0106]

[0107] Among them, A1, A2, and A3 are the areas of the receiving permeable surface RPA-disconnected impermeable surface DIA system, the natural permeable surface PA, and the connected impermeable surface DCIA in the catchment area respectively; R RPA-DIA and R PA are the surface runoff of the receiving permeable surface RPA-disconnected impervious surface DIA system and the natural permeable surface PA in the catchment area; P is the total rainfall of the rainfall event; I DCIA It indicates the amount of depression storage loss of the connected impervious surface.

[0108] Based on the contents of the above-mentioned device embodiment, as an optional embodiment, the urban rainfall-runoff relationship simulation device based on sensitivity function provided in the embodiment of the present invention further includes: a third sub-module, used to realize that the fitting parameter a represents the minimum value reached by RI sensitivity, which is the difference between the runoff coefficients of the permeable surface and the impervious surface under extreme rainfall conditions, and is proportional to the infiltration capacity of the permeable surface; the fitting parameter b represents the impact of changes in the total amount of rainfall on the RI sensitivity, which is related to the rate at which the infiltration capacity of the permeable surface decays with increasing soil moisture; the fitting parameter c reflects the impact of changes in rainfall intensity on the RI sensitivity, and is related to the change in the relative infiltration capacity of the permeable surface with rainfall intensity.

[0109] Based on the content of the above-mentioned device embodiment, as an optional embodiment, the urban rainfall-runoff relationship simulation device based on sensitivity function provided in the embodiment of the present invention also includes: a fourth sub-module, which is used to implement the above, including: when calculating the runoff of the catchment area, dividing the underlying surface into three parts according to the infiltration capacity of the underlying surface and the runoff generation characteristics: a receiving permeable surface RPA-disconnected impermeable surface DIA system, a natural permeable surface PA and a connected impermeable surface DCIA, calculating the runoff for each part, and calculating the total surface runoff of the catchment area according to the area weighted method.

[0110] Based on the content of the above device embodiment, as an optional embodiment, the urban rainfall-runoff relationship simulation device based on sensitivity function provided in the embodiment of the present invention further includes: a fifth submodule for realizing the above, including: calculating the runoff generation of the receiving permeable surface RPA-disconnected impermeable surface DIA system and the natural permeable surface PA according to the rainfall AR in the previous three days 3d The threshold x is used to divide the initial soil moisture of all rainfall events, and the values ​​of the fitting parameters b and c are calculated to reflect the influence of the initial soil moisture on runoff generation.

[0111] The method of the embodiment of the present invention is implemented by electronic devices, so it is necessary to introduce the relevant electronic devices. Based on this purpose, the embodiment of the present invention provides an electronic device, such as Figure 3 As shown, the electronic device includes: at least one processor, a communications interface, at least one memory, and a communications bus, wherein the at least one processor, the communications interface, and the at least one memory communicate with each other via the communications bus. The at least one processor can call logic instructions in the at least one memory to execute all or part of the steps of the methods provided in the aforementioned method embodiments.

[0112] In addition, the logic instructions in the at least one memory mentioned above can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when sold or used as an independent product. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each method embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0113] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in one location or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of the present embodiment. Persons of ordinary skill in the art will be able to understand and implement the present invention without inventive effort.

[0114] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and of course can also be implemented by hardware. Based on this understanding, the essence of the above technical solution or the part that contributes to the existing technology can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiment.

[0115] The flowcharts and block diagrams in the accompanying drawings show the possible architectures, functions and operations of the systems, methods and computer program products according to multiple embodiments of the present invention. Based on this understanding, each box in the flowchart or block diagram can represent a module, program segment or part of the code, and the module, program segment or part of the code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, or sometimes in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart, can be implemented with a dedicated hardware-based system that performs the specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0116] It should be noted that the terms "comprise," "include," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, the elements defined by the phrase "comprise..." do not preclude the presence of additional identical elements in the process, method, article, or apparatus comprising the elements.

[0117] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for simulating urban rainfall-runoff relationship based on sensitivity function, characterized in that: include: Step 1: determine the area of ​​different underlying surface types in the catchment area and generalize the runoff path; Step 2: Construct a watershed runoff calculation formula: Based on the runoff coefficient R-impervious surface area I sensitivity S R-I Function, the expression is: Among them, a, b, and c are fitting parameters related to the underlying surface conditions; P represents the total rainfall of the rainfall event; P 0.5h represents the maximum rainfall in 0.5 hours. For the receiving permeable surface RPA-disconnected impervious surface DIA system, the corresponding surface runoff coefficient α is calculated according to formula (2): Where P is the total rainfall of the rainfall event; I a,imp S is the storage capacity of impervious surface depression; R-I is the runoff coefficient-impervious surface area sensitivity function; IR is the system impervious area ratio; Substituting (1) into (2), the surface runoff of the receiving permeable surface RPA-disconnected impervious surface DIA system is calculated by (3): Among them, IR is the area ratio of disconnected impervious surface in the receiving permeable surface RPA-disconnected impervious surface DIA system. When calculating the natural pervious surface PA subsystem, I a,imp and IR takes the value of 0.

2. The urban rainfall-runoff relationship simulation method based on sensitivity function according to claim 1 is characterized in that: The step 1 specifically includes: according to the distribution characteristics of the underlying impervious surface after the construction of the sponge city, the urban catchment area is generalized into three parts: the receiving permeable surface RPA-disconnected impervious surface DIA system, the natural permeable surface PA and the connected impervious surface DCIA, and the areas A1, A2 and A3 of the three parts, as well as the impervious area ratio IR in the receiving permeable surface RPA-disconnected impervious surface DIA system are determined.

3. The urban rainfall-runoff relationship simulation method based on sensitivity function according to claim 2 is characterized in that: In the I a,imp After IR is 0, it also includes: the rainfall AR in the previous three days 3d There is a threshold x. There is a significant difference in runoff coefficients between two groups of rainfall events with values ​​greater than or less than the threshold x. The initial soil moisture levels of the rainfall events are divided, and different soil moisture levels correspond to different values ​​of the fitting parameters b and c. The average runoff coefficient of the catchment area is calculated using the area-weighted method based on the runoff coefficients of the receiving permeable surface RPA-disconnected impervious surface DIA system, the natural permeable surface PA, and the connected impervious surface DCIA: Among them, A1, A2, and A3 are the areas of the receiving permeable surface RPA-disconnected impermeable surface DIA system, the natural permeable surface PA, and the connected impermeable surface DCIA in the catchment area respectively; R RPA-DIA and R PA are the surface runoff of the receiving permeable surface RPA-disconnected impervious surface DIA system and the natural permeable surface PA in the catchment area; P is the total rainfall of the rainfall event; I DCIA It indicates the amount of depression storage loss of the connected impervious surface.

4. The urban rainfall-runoff relationship simulation method based on sensitivity function according to claim 3 is characterized in that: The fitting parameter a represents the minimum value of RI sensitivity. It is the difference between the runoff coefficients of permeable and impervious surfaces under extreme rainfall conditions and is proportional to the infiltration capacity of the permeable surface. The fitting parameter b indicates the impact of changes in total rainfall on RI sensitivity and is related to the rate at which the infiltration capacity of the permeable surface decays with increasing soil moisture. The fitting parameter c reflects the impact of changes in rainfall intensity on RI sensitivity and is related to the change in the relative infiltration capacity of the permeable surface with rainfall intensity.

5. The urban rainfall-runoff relationship simulation method based on sensitivity function according to claim 4 is characterized in that: The method includes: when calculating the runoff of the catchment area, dividing the underlying surface into three parts according to the infiltration capacity of the underlying surface and the runoff generation characteristics, namely the receiving permeable surface RPA-disconnected impervious surface DIA system, the natural permeable surface PA and the connected impervious surface DCIA, calculating the runoff for each part, and calculating the total surface runoff of the catchment area according to the area weighted method.

6. The urban rainfall-runoff relationship simulation method based on sensitivity function according to claim 5 is characterized in that: The above includes: when calculating the flow generation of receiving permeable surface RPA-disconnected impermeable surface DIA system and natural permeable surface PA, the rainfall AR in the previous three days is used. 3d The threshold x is used to divide the initial soil moisture of all rainfall events, and the values ​​of the fitting parameters b and c are calculated to reflect the influence of the initial soil moisture on runoff generation.

7. A device for simulating the relationship between urban rainfall and runoff based on a sensitivity function, characterized in that: include: The first main module is used to implement step 1, determine the area of ​​different underlying surface types in the catchment area and generalize the runoff path; The second main module is used to implement step 2 and construct the watershed runoff calculation formula: based on the runoff coefficient R-impervious surface area I sensitivity S R-I Function, the expression is: Among them, a, b, and c are fitting parameters related to the underlying surface conditions; P represents the total rainfall of the rainfall event; P 0.5h represents the maximum rainfall in 0.5 hours. For the receiving permeable surface RPA-disconnected impervious surface DIA system, the corresponding surface runoff coefficient α is calculated according to formula (2): Where P is the total rainfall of the rainfall event; I a,imp S is the storage capacity of impervious surface depression; R-I is the runoff coefficient-impervious surface area sensitivity function; IR is the system impervious area ratio; Substituting (1) into (2), the surface runoff of the receiving permeable surface RPA-disconnected impervious surface DIA system is calculated by (3): Among them, IR is the area ratio of disconnected impervious surface in the receiving permeable surface RPA-disconnected impervious surface DIA system. When calculating the natural pervious surface PA subsystem, I a,imp and IR takes the value of 0.

8. An electronic device, characterized in that: include: At least one processor, at least one memory and a communication interface; wherein, The processor, memory and communication interface communicate with each other; The memory stores program instructions that can be executed by the processor, and the processor calls the program instructions to execute the method according to any one of claims 1 to 6.

9. A non-transitory computer-readable storage medium, characterized in that The non-transitory computer-readable storage medium stores computer instructions, which cause the computer to execute the method of any one of claims 1 to 6.

Images