CN113836758A - Water quantity and water quality simulation calculation method for low-influence development facility - Google Patents
Water quantity and water quality simulation calculation method for low-influence development facility Download PDFInfo
- Publication number
- CN113836758A CN113836758A CN202110835175.4A CN202110835175A CN113836758A CN 113836758 A CN113836758 A CN 113836758A CN 202110835175 A CN202110835175 A CN 202110835175A CN 113836758 A CN113836758 A CN 113836758A
- Authority
- CN
- China
- Prior art keywords
- layer
- water
- formula
- low
- water quality
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
- G06F30/23—Design optimisation, verification or simulation using finite element methods [FEM] or finite difference methods [FDM]
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2111/00—Details relating to CAD techniques
- G06F2111/10—Numerical modelling
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2113/00—Details relating to the application field
- G06F2113/08—Fluids
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Computer Hardware Design (AREA)
- Evolutionary Computation (AREA)
- Geometry (AREA)
- General Engineering & Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Management, Administration, Business Operations System, And Electronic Commerce (AREA)
Abstract
A water quantity and water quality simulation calculation method of a low-influence development facility comprises the following steps: 1. simulating the transmission process of hydrological runoff, canal water flow and water quality of a research area, and calculating the accumulation amount and the scouring amount of pollutants under the current condition; 2. solving the storage stagnation and transmission conversion process of water quantity and water quality based on a water quantity continuity equation and a pollutant first-level degradation reaction equation of each structural layer of the low-impact development facility; 3. and analyzing the control effect of the low-impact development facilities on water quantity and water quality, and evaluating the target accessibility of the low-impact development design scheme. The method comprehensively considers the regulation and storage and reduction capacity of each structural layer on water quantity and water quality, and starts from the fine simulation of the water quantity and the water quality of each structural layer of the low-influence development facility, so that the fine simulation of the water quantity and the water quality of the low-influence development facility is realized, and indexes such as surface runoff control rate and pollutant reduction rate are evaluated.
Description
Technical Field
The invention relates to the technical field of simulation of low-impact development facilities in sponge city construction, in particular to a water quantity and water quality simulation calculation method for the low-impact development facilities.
Background
In recent years, sponge cities are fierce, limited rainwater is preferentially reserved when the urban drainage system capacity is improved, natural force is preferentially used for drainage, and a 'sponge city' with natural accumulation, natural penetration and natural purification is built.
In sponge city construction, low-influence development facilities are important engineering measures and have the functions of controlling surface runoff and surface source pollution, and accurate evaluation of the effect of the low-influence development facilities has important significance on auxiliary scheme design. At present, the water quantity and water quality simulation of low-influence development facilities by using a mathematical model has related researches, but the calculation methods of the water quantity and the water quality in the model are different.
Disclosure of Invention
The invention provides a water yield and water quality simulation calculation method of a low-impact development facility, which comprehensively considers the regulation and reduction capacity of each structural layer on water yield and water quality, realizes the fine simulation of the water yield and the water quality of the low-impact development facility from the aspect of fine simulation of the water yield and the water quality of each structural layer of the low-impact development facility, and evaluates indexes such as surface runoff control rate, pollutant reduction rate and the like.
As conceived above, the technical scheme of the invention is as follows: a water quantity and water quality simulation calculation method of a low-influence development facility is characterized by comprising the following steps: the method comprises the following steps:
simulating the transmission process of hydrological runoff, canal water flow and water quality of a research area, and calculating the accumulation amount and the scouring amount of pollutants under the current condition;
solving the stagnation storage and transmission conversion process of water quantity and water quality based on a water quantity continuity equation and a pollutant first-level degradation reaction equation of each structural layer of the low-impact development facility;
and step three, analyzing the control effect of the low-impact development facilities on water quantity and water quality, and evaluating the target accessibility of the low-impact development design scheme.
Further, the hydrological runoff calculation in the first step comprises surface runoff yield and surface confluence, the infiltration amount of the surface runoff yield is calculated by solving a Hoton Horton formula, the surface confluence is calculated by adopting a nonlinear reservoir equation, the calculation of the transmission process of the canal water flow and the water quality is calculated by adopting a Mastokyo-Kouzu method or a modified Puls method, the accumulation amount of pollutants is calculated by adopting an index accumulation algorithm, and the scouring amount is calculated by adopting an index scouring algorithm or an EMC scouring algorithm.
Further, the method for calculating the infiltration amount of the surface produced flow by adopting a Hoton Horton formula comprises the following steps:
the calculation formula of the infiltration capacity and the infiltration amount in rainy season is as follows:
in the formula: f is infiltration capacity at the moment t, mm/s; f is the infiltration amount at the moment t, mm; f. of∞Is the minimum infiltration capacity, mm/s; f. of0Is the maximum infiltration capacity, mm/s; t is the infiltration time, s; k is a radical ofdIs an infiltration attenuation coefficient, s-1；
Secondly, the calculation formula of the infiltration capacity in dry seasons is as follows:
in the formula: t is twF is f in the surface infiltration capacity recovery curve∞Time corresponding to time, krFor the recovery coefficient of infiltration, s-1。
Further, the method for solving the earth surface confluence by adopting a nonlinear reservoir method comprises the following steps:
the surface runoff calculation formula is as follows:
in the formula: a is the area of the catchment area, m2(ii) a n is the Manning coefficient of the catchment area; w is the characteristic width of the catchment area, m; s is the gradient of the catchment area, d is the surface water depth m; dsThe surface depression depth is m;
the calculation formula of the surface water depth along with the time is as follows:
in the formula: d is the surface water depth m; i is rainfall intensity, mm/s; e is evaporation intensity, mm/s; f is the infiltration rate, mm/s; q is the runoff, mm/s.
Further, the calculation method of the masjing root method adopted in the transmission process of the canal water flow and the water quality is as follows: the tank storage equation is adopted to replace a momentum equation, the water balance equation is adopted to replace a continuity equation, and the calculation formula is as follows:
in the formula: v is the tank storage amount, m3(ii) a I is the inflow, m3S; q is the flow rate, m3S; Δ t is the calculation step length, s; i and i-1 respectively represent the physical quantities of the current moment and the last moment, K, X respectively represent the Mas Jing root parameter, and have no specific physical significance;
the following equations 6 and 7 are solved:
Qi＝CXIi+CYVi-1 (8)
wherein CX and CY are K, X and delta t functions, and the calculation formula is as follows:
the limiting conditions are as follows:
the relation is obtained from the constraint:
the above is a single river reach calculation formula, and for the multi-river reach case, K/N (N is the number of sub-river reach) is used as a new K value to participate in the calculation.
Further, the calculation method of the modified Puls model adopted in the transmission process of the canal water flow and the water quality is as follows: the modified PULS model, namely a horizontal pool model, adopts a finite difference format, couples a momentum equation expressed by experience, and calculates the pipeline outflow by giving an inflow process line and a regulation-outflow relation curve;
the continuity equation is:
in the formula:
is the average out-flow, m, over a time step3/s；
Is the average incoming flow, m, over a time step3S; l is the length of the pipeline, m; delta A is the variation of the cross-sectional area of the pipeline, m2(ii) a Delta S is the pipeline regulation and storage variation; Δ t is the time step, s;
assuming that the flow rate varies linearly in time steps, the above equation can be written as:
in the formula: si+1For regulating the storage capacity, m, of the pipeline at the next moment3；SiFor regulating the storage capacity, m, of the pipeline at the present moment3；Qi+1For the next moment of the pipeline outlet flow, m3/s；QiM is the current time of the pipeline outlet flow3/s；Ii+1For the next moment of the pipe inflow, m3/s；IiM is the current pipe inflow3/s；
Si+1And Qi+1The unknown number is the unique unknown number calculated by utilizing a storage-outflow relation curve, and the storage-outflow relation curve is calculated by adopting a Manning formula.
Further, the method for calculating the accumulation amount of the surface runoff pollutants by the exponential accumulation method comprises the following steps: the basic equation is as follows:
in the formula: b is the accumulated amount of pollutants, kg/hm2；BmaxIs the maximum cumulative amount of pollutants, kg/hm2；KBIs an exponential cumulative coefficient of contamination, day-1(ii) a t is the cumulative time, day.
Further, the method for calculating the scouring amount of the surface runoff pollutants by the exponential scouring method comprises the following steps: the basic equation is as follows:
mB(t)＝mB(0)e-kt (17)
W(t)＝mB(0)-mB(t)＝mB(0)(1-e-kt) (18)
in the formula: w (t) is the flushing amount of the pollutants at the time t, kg; m isB(0) Is the initial cumulant of the earth's surface, kg; m isB(t) is the earth surface cumulant at the moment t; kg; k is an index coefficient, h,
the above equation is obtained by integrating equation (19).
In the formula: w is the rate of flushing, kg/h,
since k is related to the radial flow rate, it can be expressed as equation (20),
wherein: kWIs the coefficient of erosion, mm-1(ii) a q is the runoff of the catchment area, mm/h; n is a radical ofWIs the scouring index.
Thus, the formula (21) can be obtained,
further, the method for calculating the scouring amount of the surface runoff pollutants by the EMC scouring method comprises the following steps: the scouring concentration in the runoff scouring process is regarded as the same value, namely the field average concentration.
Further, the specific steps of the second step include:
(1) calculating the water storage stagnation and transmission process of the low-influence development facility by adopting a water continuity equation;
the low-impact development facility consists of five structural layers, which are respectively: the surface course, the layer of mating formation, soil layer, regulation layer and evacuation bed course, each structural layer water yield computational formula is:
surface layer:
a soil layer:
a storage layer:
paving a layer:
and (3) emptying the cushion layer:
in the formula: is the face layer void fraction; d1 is surface water depth, m; i is the rainfall of the surface layer, m/s; q0 is the runoff of the catchment area merging into the surface layer, m/s; e1 is the amount of evaporation of the surface layer, m/s; f1 is the infiltration amount from the surface layer to the soil layer, m/s; q1 is surface layer outflow rate, m/s; d2 is soil layer thickness, m; the water content of the soil layer; e2 is the evapotranspiration of the soil layer, m/s; f2 is the infiltration amount from the soil layer to the storage regulating layer, m/s; adjusting the porosity of the storage layer; d3 is the depth of reservoir water, m; e3 is the evapotranspiration of the storage regulating layer, m/s; f3 is the infiltration amount from the regulation layer to the lower soil (assuming the saturated hydraulic conductivity of the lower soil), m/s; q3 is blind pipe outlet flow rate, m/s; phi is a4The porosity of the cushion layer is emptied; d4M is the depth of the water of the cushion layer; f. of4The infiltration amount from the soil layer to the emptying cushion layer is m/s; e.g. of the type4In order to exhaust the evapotranspiration amount of the cushion layer, m/s; q. q.s4M/s to evacuate the outflow of the cushion layer; d4To thickness of the paving layer, θ4The water content of the soil layer; e.g. of the type5The evaporation capacity of the pavement layer is m/s; f. of5M/s is the output flow of the pavement layer;
(2) calculating the water quality reduction process of the low-impact development facility by adopting a pollutant first-stage degradation method;
in the water quality calculation, the pollutants of each structural layer are assumed to be completely mixed, the removal effect of the pollutants is reflected by setting a first-level degradation coefficient of each structural layer, and the calculation formula is as follows:
in the formula: v is the water quantity of the structural layer, m 3; c is the water quality concentration in the structural layer, mg/L; c. C0The inflow concentration of the structural layer is mg/L; q. q.s0The inflow rate of the structural layer is m/s; q is the structural layer outlet flow, m/s; k is the first-order degradation coefficient of water quality in the structural layer, s-1。
Further, in the second step, the surface runoff is calculated by using a manning formula, and if the width of the surface runoff is far greater than the depth of the surface runoff, the calculation formula of the surface runoff is obtained by derivation and is as follows:
in the formula: n is1The coefficient of surface roughness; s1Is a slope; w1Is the flow length, m; d1Surface depression depth, m; a. the1Is the area of the surface layer, m2；
The evapotranspiration calculation formula of the surface layer, the soil layer and the storage regulating layer is as follows:
e1＝min[E0(t),d1/Δt] (26)
e2＝min[E0(t)-e1,(θ2-θWP)D2/Δt] (27)
in the formula: e0(t) is the potential evaporation capacity of the system at the moment t, m/s; thetaWPPorosity corresponding to wilting points;
when the water content of the soil layer is lower than the porosity of the wilting point, the soil layer does not evaporate; if the soil layer is saturated, no evapotranspiration exists in the storage layer; if the soil layer and the storage regulating layer have surface layer infiltration amount, no evapotranspiration occurs;
the formula for calculating the infiltration amount from the soil layer to the storage regulating layer is as follows:
in the formula: k2SThe saturated hydraulic conductivity of the soil layer is m/s; HCO is the attenuation coefficient in a relation curve of hydraulic conductivity and water content; thetaFCThe field water capacity;
the blind pipe outlet flow calculation formula is as follows:
in the formula: h is3Water head above the blind pipe, m; c3DThe blind pipe outflow coefficient; eta3DBlind tube outflow index.
The water head calculation formula above the blind pipe is as follows:
in the formula: d3DThe embedding height of the blind pipe in the storage layer is set;
the pavement layer has the calculation formula as follows:
in the formula: d4To thickness of the paving layer, θ4The water content of the soil layer; e.g. of the type5The evaporation capacity of the pavement layer is m/s; f. of5M/s is the output flow of the pavement layer;
the empty pad calculation formula is:
in the formula: phi is a4The porosity of the cushion layer is emptied; d4M is the depth of the water of the cushion layer; f. of4The infiltration amount from the soil layer to the emptying cushion layer is m/s; e.g. of the type4In order to exhaust the evapotranspiration amount of the cushion layer, m/s; q. q.s4M/s to evacuate the outflow of the mat.
And further, selecting a certain full-year rainfall as continuous rainfall data, simulating the current working condition under the same rainfall condition and the production confluence condition and the pollution load condition of the low-influence development facility design scheme, calculating the annual runoff total control rate and the annual pollutant load reduction rate, and analyzing the target accessibility of the scheme.
The invention realizes the water quantity and water quality refined simulation of low-influence development facilities by constructing the urban water system control simulation model Simuwater, and can evaluate the indexes such as surface runoff control rate, pollutant reduction rate and the like. The model is developed by solving a Hoton formula and a nonlinear reservoir equation to calculate the production confluence of the earth surface, calculating the transmission process of the water flow of the pipeline by using a Maskikyu method or a modified Puls method, calculating the accumulation amount and the scouring amount of pollutants by using an exponential accumulation algorithm, an exponential scouring algorithm or an EMC scouring algorithm of the pollutants, and solving the storage and transmission conversion processes of water quantity and water quality based on a water quantity continuity equation and a pollutant one-level degradation reaction equation of each structural layer of a low-impact development facility, so that compared with the prior art, the model has the advantages that:
(1) the method for calculating the water flow of the pipe canal adopts a MaskJetty method or a modified Puls model method, is suitable for rapid modeling under the condition of pipeline data loss, and improves the calculation efficiency.
(2) Each structural layer of the low-influence development facility can be provided with a first-level degradation coefficient, so that the reduction condition of each structural layer on pollutants is reflected more truly.
Drawings
FIG. 1 is a graph of the recovery of surface infiltration capacity during soil drying;
FIG. 2 is a schematic diagram of the physical significance of the Massjing root method;
FIG. 3 is a regional overview;
FIG. 4 is a diagram of a Simuwater model topology;
FIG. 5 is a plot of an existing runoff process;
FIG. 6 is a low impact development facility scenario runoff process line plot;
FIG. 7 is a present contamination load process line graph;
FIG. 8 is a plot of a low impact development facility scenario pollution load process line.
Detailed Description
The present invention will be described in detail with reference to the following embodiments and the accompanying drawings. It should be understood that the examples of the present invention are for better understanding of the present invention by researchers in the field, and are not intended to limit the present invention.
The invention provides a water quantity and water quality simulation calculation method of a low-influence development facility, which comprises the following specific implementation steps of firstly constructing a control simulation model (Simuwater) based on an urban water system:
step 1: and (3) simulating the transmission process of hydrological runoff, canal water flow and water quality in the research area, and calculating the surface runoff and the pollutant load under the current condition.
(1) The hydrological runoff calculation comprises surface runoff production and surface confluence, the infiltration amount of the surface runoff production in the Simuwater model is calculated by a Hoston (Horton) formula, and the surface confluence is solved by a nonlinear reservoir method.
1) Hotten infiltration calculation method
The Hotten infiltration calculation method is used for analyzing the change process of the surface infiltration capacity and the infiltration quantity along with the time.
The calculation formula of the infiltration capacity and the infiltration amount in rainy season is as follows:
in the formula: f is infiltration capacity at the moment t, mm/s; f is the infiltration amount at the moment t, mm; f. of∞Is the minimum infiltration capacity, mm/s; f. of0Is the maximum infiltration capacity, mm/s; t is the infiltration time, s; k is a radical ofdIs an infiltration attenuation coefficient, s-1。
Secondly, the calculation formula of the infiltration capacity in dry seasons is as follows:
in the formula: t is twFor the surface infiltration capacity recovery curve (as shown in figure 1) f is f∞Time corresponding to time, krFor the recovery coefficient of infiltration, s-1。
2) Nonlinear reservoir calculation method
The catchment area is generalized to a rectangular surface with shallow water depth, and the surface has uniform slope, width and runoff outlet. After the rainfall deducts the evaporation amount, the infiltration amount and the depression storage amount, the residual water amount forms surface runoff.
The surface runoff calculation formula is as follows:
in the formula: a is the area of the catchment area, m2(ii) a n is the Manning coefficient of the catchment area; w is the characteristic width of the catchment area, m; s is the gradient of the catchment area, d is the surface water depth m; dsThe surface depression depth, m.
The calculation formula of the surface water depth along with the time is as follows:
in the formula: d is the surface water depth m; i is rainfall intensity, mm/s; e is evaporation intensity, mm/s; f is the infiltration rate, mm/s; q is the runoff, mm/s.
(2) The simulwater model uses the masjing heel method or a modified Puls model method to calculate the canal flow.
1) Masjing heel method
The masjing root method was originally used to simulate river channel currents, assuming that the water storage in the channel consists of two parts, columnar and wedge-shaped (see fig. 2). When the water flow of the pipeline is simulated by adopting the Masjing's root method, the water quantity propagation process in the pipeline is approximately regarded as the water quantity propagation process in a river channel. The MaskGen calculation method adopts a tank storage equation to replace a momentum equation and adopts a water balance equation to replace a continuity equation, and the calculation formula is as follows:
in the formula: v is the tank storage amount, m3(ii) a I is the inflow, m3S; q is the flow rate, m3S; Δ t is the calculation step length, s; i and i-1 respectively represent the physical quantities at the current moment and the last moment, and K, X respectively represent the Mas Jing root parameter, and have no specific physical significance.
The following equations 6 and 7 are solved:
Qi＝CXIi+CYVi-1 (8)
wherein CX and CY are K, X and delta t functions, and the calculation formula is as follows:
the limiting conditions are as follows:
the relation is obtained from the constraint:
the above is a single river reach calculation formula, and for the multi-river reach case, K/N (N is the number of sub-river reach) is used as a new K value to participate in the calculation.
2) Modified Puls model method
The modified PULS model, namely the horizontal pool model, adopts a finite difference format and couples an empirically expressed momentum equation, and calculates the pipeline outflow by giving an inflow process line and a regulation-outflow relation curve.
The continuity equation is:
in the formula:
is the average out-flow, m, over a time step3/s；
Is the average incoming flow, m, over a time step3S; l is the length of the pipeline, m; delta A is the variation of the cross-sectional area of the pipeline, m2(ii) a Delta S is the pipeline regulation and storage variation; Δ t is the time step, s.
Assuming that the flow rate varies linearly in time steps, the above equation can be written as:
in the formula: si+1For regulating the storage capacity, m, of the pipeline at the next moment3；SiFor regulating the storage capacity, m, of the pipeline at the present moment3；Qi+1For the next moment of the pipeline outlet flow, m3/s；QiM is the current time of the pipeline outlet flow3/s；Ii+1For the next moment of the pipe inflow, m3/s；IiM is the current pipe inflow3/s。
Si+1And Qi+1For unknown numbers, regulation-discharge can be usedThe flow relation curve is calculated as a unique unknown number, and the storage-outflow relation curve is calculated by adopting a Manning formula.
(3) And calculating the water quality, namely calculating the surface runoff pollutants. In the Simuwater model, the accumulated amount of the pollutants is calculated by adopting an exponential accumulation method, and the scouring amount of the pollutants is calculated by adopting an exponential scouring method or an EMC scouring method.
1) The exponential accumulation method, i.e. the accumulation amount grows exponentially with time until the maximum accumulation amount, and the basic equation is as follows:
in the formula: b is the accumulated amount of pollutants, kg/hm2；BmaxIs the maximum cumulative amount of pollutants, kg/hm2；KBIs an exponential cumulative coefficient of contamination, day-1(ii) a t is the cumulative time, day.
2) The exponential scouring method, i.e. the scouring quantity increases exponentially with time until the initial cumulant, and the basic equation is as follows:
mB(t)＝mB(0)e-kt (17)
W(t)＝mB(0)-mB(t)＝mB(0)(1-e-kt) (18)
in the formula: w (t) is the flushing amount of the pollutants at the time t, kg; m isB(0) Is the initial cumulant of the earth's surface, kg; m isB(t) is the earth surface cumulant at the moment t; kg; k is the index coefficient, h.
The above equation is obtained by integrating equation (19).
In the formula: w is the flushing rate, kg/h.
Since k is related to the radial flow rate, it can be expressed by equation (20).
Wherein: kWIs the coefficient of erosion, mm-1(ii) a q is the runoff of the catchment area, mm/h; n is a radical ofWIs the scouring index.
Thus, formula (21) can be obtained.
3) The EMC scouring method considers the scouring concentration in the runoff scouring process as the same value, namely field-average concentration.
Step 2: simulating the accumulation, transmission and degradation processes of water quantity and water quality of low-influence development facilities, and calculating the surface runoff and the pollutant load of the design scheme.
The low impact development facility in the simulwater model includes: bioretention facilities, rain gardens, green roofs, infiltration canals, water permeable pavements, rainwater tanks and grass planting ditches. In the calculation, the following assumptions are made:
(1) The Simuwater model adopts a water continuity equation to calculate the water storage and transmission process of the low-impact development facility
The low-impact development facility consists of five structural layers, which are respectively: the soil layer comprises a surface layer, a pavement layer, a soil layer, a storage regulation layer and an emptying cushion layer. Each structural layer all has the evapotranspiration effect, and the rainfall is received to the surface course and the runoff converges, and after the surface course saturation, partly infiltration inflow soil horizon, partly inflow overflow well of unnecessary water volume, after the soil horizon saturation, unnecessary water volume continues to infiltrate to the regulation layer down, and after the regulation layer saturation, unnecessary water volume continues to infiltrate to the underground, if the regulation layer is equipped with the blind pipe, when the regulation layer water level is higher than the blind pipe height, the water yield passes through the blind pipe and flows into the overflow well.
1) Water quantity calculation for bioretention facilities
The bioretention facility structural layer comprises a surface layer, a soil layer and a regulation and storage layer, and the calculation formula of each layer is as follows:
surface layer:
a soil layer:
a storage layer:
in the formula: phi is a1Is the face layer void fraction; d1Is the surface water depth, m; i is the rainfall of the surface layer, m/s; q. q.s0The runoff quantity of the water gathering area which is gathered into the surface layer is m/s; e.g. of the type1The surface layer evapotranspiration amount is m/s; f. of1The infiltration amount from the surface layer to the soil layer is m/s; q. q.s1The surface layer outlet flow is m/s; d2Is the thickness of the soil layer, m; theta2The water content of the soil layer; e.g. of the type2The evapotranspiration amount of the soil layer is m/s; f. of2The infiltration amount from the soil layer to the storage regulation layer is m/s; phi is a3Adjusting the porosity of the storage layer; d3Adjusting the depth of water in the storage layer by m; e.g. of the type3The evaporation capacity of the storage layer is adjusted in m/s; f. of3The infiltration amount from the storage layer to the lower soil (assumed to be the saturated hydraulic conductivity of the lower soil), m/s; q. q.s3M/s for blind pipe outlet flow.
The surface runoff is calculated by using a Manning formula, and if the width of the surface runoff is far greater than the depth of the surface runoff, the calculation formula of the surface runoff is obtained by derivation:
in the formula: n is1The coefficient of surface roughness; s1Is a slope; w1Is the flow length, m; d1Surface depression depth, m; a. the1Is the area of the surface layer, m2。
The evapotranspiration calculation formula of the surface layer, the soil layer and the storage regulating layer is as follows:
e1＝min[E0(t),d1/Δt] (26)
e2＝min[E0(t)-e1,(θ2-θWP)D2/Δt] (27)
in the formula: e0(t) is the potential evaporation capacity of the system at the moment t, m/s; thetaWPPorosity corresponding to wilting points.
When the water content of the soil layer is lower than the porosity of the wilting point, the soil layer does not evaporate; if the soil layer is saturated, no evapotranspiration exists in the storage layer; if the soil layer and the storage regulating layer have surface layer infiltration amount, no evapotranspiration occurs.
The formula for calculating the infiltration amount from the soil layer to the storage regulating layer is as follows:
in the formula: k2SThe saturated hydraulic conductivity of the soil layer is m/s; HCO is the attenuation coefficient in a relation curve of hydraulic conductivity and water content; thetaFCIs the field water capacity.
The blind pipe outlet flow calculation formula is as follows:
in the formula: h is3Water head above the blind pipe, m; c3DThe blind pipe outflow coefficient; eta3DBlind tube outflow index.
The water head calculation formula above the blind pipe is as follows:
in the formula: d3DThe height of the blind pipe embedded in the storage layer is adjusted.
2) Rainwater garden water quantity calculation
The structure layer of the rainwater garden comprises a surface layer and a soil layer, see the formula (22-23), f2The infiltration amount from the soil layer to the regulation layer is not represented any more, but the infiltration amount from the soil layer to the lower soil layer is represented, and the calculation is carried out by the formula (29).
3) Green roof water volume calculation
The structural layer of the green roof comprises a surface layer, a soil layer and an emptying cushion layer, the surface layer and the soil layer are calculated according to a formula (22-23), and the emptying cushion layer is calculated according to the formula:
in the formula: phi is a4The porosity of the cushion layer is emptied; d4M is the depth of the water of the cushion layer; f. of4The infiltration amount from the soil layer to the emptying cushion layer is m/s; e.g. of the type4In order to exhaust the evapotranspiration amount of the cushion layer, m/s; q. q.s4M/s to evacuate the outflow of the mat.
Assuming that the inside of the drainage cushion layer is uniform flow of an open channel, the flow calculation formula of the drainage cushion layer is as follows:
in the formula: n is2To evacuate the roughness factor of the mat.
4) Calculation of seepage water volume
The structural layer of the infiltration channel comprises a surface layer and a regulation layer, which are shown in formulas (22) and (24).
5) Water-permeable paving water quantity calculation
The permeable pavement structure layer comprises a surface layer, a pavement layer and a regulation and storage layer. The calculation of the surface layer and the regulation and storage layer is shown in formulas (22) and (24), and the calculation formula of the pavement layer is as follows:
in the formula: d4To thickness of the paving layer, θ4The water content of the soil layer; e.g. of the type5The evaporation capacity of the pavement layer is m/s; f. of5M/s for the flow of the paving layer.
6) Rainwater tank water volume calculation
The rainwater jar's structural layer only has the regulation layer, and the porosity of regulation layer is 1.0, and the computational formula is:
in the formula: f. of6M/s is the amount of water entering the storage layer; q. q.s5M/s is used for regulating the output flow of the storage layer.
Calculating q3Time, let η be3DIs 0.5.
7) Grass planting ditch water amount calculation
The structure layer of the grass planting ditch only has a surface layer, and the calculation formula is as follows:
in the formula: a. the1Surface area corresponding to surface layer depth of water, m2(ii) a A is the area of the grass planting ditch.
The surface area calculation formula is:
in the formula: w1The width m corresponding to the storage depth on the surface of the grass planting ditch; sXIs a slope gradient.
Discharge q of grass planting ditch1The calculation formula of A is as follows:
in the formula: a. theXM2 for cross-sectional area; rXIs the hydraulic radius, m.
AXAnd RXThe calculation formula is as follows:
AX＝d1(W1-2SXD1+d1SX)φ1 (39)
(2) the Simuwater model adopts a pollutant first-level degradation method to calculate the water quality reduction process of the low-impact development facility
The low influence development facility realizes the effect of getting rid of the inflow pollutant through self regulation and storage and reaction, and the pollutant of supposing each structural layer is for mixing completely in the water quality calculation, and each structural layer is through setting for one-level degradation coefficient, and the effect of getting rid of reaction pollutant, the computational formula is:
in the formula: v is the water quantity of the structural layer, m 3; c is the water quality concentration in the structural layer, mg/L; c. C0The inflow concentration of the structural layer is mg/L; q. q.s0The inflow rate of the structural layer is m/s; q is the structural layer outlet flow, m/s; k is the first-order degradation coefficient of water quality in the structural layer, s-1。
And constructing a simulater based on the urban water system control simulation model based on the calculation method.
And step 3: and analyzing the control effect of the low-impact development facilities on water quantity and water quality, and evaluating the target accessibility of the low-impact development design scheme.
Selecting a certain full-year rainfall as continuous rainfall data, simulating the current working condition under the same rainfall condition and the production confluence condition and the pollution load condition of a low-influence development facility design scheme, calculating the annual runoff total control rate and the annual pollutant load reduction rate, and analyzing the target accessibility of the scheme.
(1) Annual runoff total quantity control effect analysis of low-impact development facility
And (4) counting the runoff change value at the drainage port, and analyzing the control effect of the low-influence development facility on the flood peak flow and the annual runoff total amount.
(2) Analysis of pollutant load reduction effect of low-impact development facility
And (4) counting the change value of the pollutant concentration at the discharge outlet and the daily pollution load, and analyzing the weakening effect of the low-influence development facility on the pollution load.
(3) Target reachability analysis
And calculating the total annual runoff control rate and the reduction rate of the annual pollutant load of the low-impact development facility and analyzing the target accessibility of the scheme.
The following provides specific application examples of the present invention, which are implemented as follows:
step 1: constructing a SimuWater current water quantity and water quality model
Firstly, a research area is divided into 26 catchment areas by combining with regional vector information (such as a map, a drainage pipeline walking diagram, a cell road diagram and the like) (as shown in fig. 3), and a Simuwater model topological structure (such as fig. 4) is established according to topological relations of the catchment areas, pipelines, inspection wells and the like.
Secondly, setting model parameters, including the area of a catchment area, the length of flow, the impermeable percentage, the permeable surface Manning coefficient, the impermeable surface Manning coefficient, the permeable surface depression storage capacity, the impermeable surface depression storage capacity, infiltration, land utilization area ratio and other parameters; parameters such as pipe diameter, length and gradient of the pipeline; the class of contaminant; cumulative parameters and washout parameters for different underlying surfaces.
And finally, setting parameters of the model such as rainfall, evaporation, simulation duration, simulation step length and the like.
Step 2: water yield and water quality model for Simuwater low-influence development facility
Firstly, according to a design scheme, determining the type of low-impact development facilities in a research area, and calculating the area and the area ratio of the low-impact development facilities in each catchment area.
And secondly, setting low-influence development facility parameters of the model, including physical parameters and first-level degradation parameters of each structural layer. Wherein the physical parameters of the surface layer comprise the height of a dike dam, the coverage rate of vegetation, the surface roughness, the surface gradient and the like; physical parameters of the soil layer comprise thickness, porosity, actual water content, wilting point, conductivity gradient and the like; physical parameters of the storage regulating layer comprise thickness, porosity, leakage rate and the like; physical parameters of the pavement layer comprise thickness, void ratio, permeability and the like; the physical parameters of the drainage cushion layer comprise a drainage coefficient, a drainage index, a drainage offset height and the like.
And finally, calculating the model, checking parameters such as continuity errors of the model and the like, and analyzing whether the parameters are in a reasonable range.
And step 3: and (5) carrying out statistical analysis on the water quantity and water quality simulation result to evaluate the effect of low-impact development facilities.
Firstly, extracting the runoff process line at the model drainage port in the step 1 and the step 2, and counting the total annual runoff amount. And (5) analyzing the control conditions of the low-impact development facilities on the flood peak flow and the annual runoff total amount (such as figures 5-6).
And secondly, extracting a pollutant concentration process line at the model discharge port in the step 1 and the step 2, and calculating daily pollutant load and annual pollutant load total. The reduction of the pollutant load by the low impact development facility is analyzed (as in figures 7-8).
Finally, the effect of the low impact development facility was evaluated. Analysis shows that the low-impact development facilities obviously reduce the peak flow and the total annual runoff amount at the drainage port, the total annual runoff amount control rate reaches 83 percent, and the design target that the total annual runoff amount control rate is 72 percent in the design scheme is met; the low-influence development facilities obviously reduce the total annual pollutant load at the discharge outlet, so that the annual pollutant load reduction rate reaches 50.2 percent, and the design target that the area-source pollutant reduction rate in the design scheme is more than 45 percent is met. Thus, the design scheme can achieve the target of controlling the total annual runoff quantity and the total annual pollutant load.
The above is a detailed description of the water quantity and water quality simulation calculation method for a low-impact development facility provided by the invention. It should be understood that the present invention is not limited to the above-described method steps and calculation procedures, the above-described embodiments are illustrative only and not intended to be limiting, and various changes and modifications may be made by those skilled in the art based on the present invention and fall within the scope of the present invention.
Claims (12)
1. A water quantity and water quality simulation calculation method of a low-influence development facility is characterized by comprising the following steps: the method comprises the following steps:
simulating the transmission process of hydrological runoff, canal water flow and water quality of a research area, and calculating the accumulation amount and the scouring amount of pollutants under the current condition;
solving the stagnation storage and transmission conversion process of water quantity and water quality based on a water quantity continuity equation and a pollutant first-level degradation reaction equation of each structural layer of the low-impact development facility;
and step three, analyzing the control effect of the low-impact development facilities on water quantity and water quality, and evaluating the target accessibility of the low-impact development design scheme.
2. The water quantity and water quality simulation calculation method of the low-influence development facility according to claim 1, characterized in that: step one, hydrological runoff calculation comprises surface runoff production and surface confluence, the infiltration amount of the surface runoff production is calculated by solving a Hoton Horton formula, the surface confluence is calculated by adopting a nonlinear reservoir equation, the calculation of the transmission process of the canal water flow and the water quality is calculated by adopting a Mastokyo-Kouch method or a modified Puls method, the accumulation amount of pollutants is calculated by adopting an index accumulation algorithm, and the scouring amount is calculated by adopting an index scouring algorithm or an EMC scouring algorithm.
3. The water quantity and water quality simulation calculation method of the low-influence development facility according to claim 2, characterized in that: the method for calculating the infiltration amount of the surface produced flow by adopting the Hoton Horton formula comprises the following steps:
the calculation formula of the infiltration capacity and the infiltration amount in rainy season is as follows:
in the formula: f is infiltration capacity at the moment t, mm/s; f is the infiltration amount at the moment t, mm; f. of∞Is the minimum infiltration capacity, mm/s; f. of0Is the maximum infiltration capacity, mm/s; t is the infiltration time, s; k is a radical ofdIs an infiltration attenuation coefficient, s-1；
Secondly, the calculation formula of the infiltration capacity in dry seasons is as follows:
in the formula: t is twF is f in the surface infiltration capacity recovery curve∞Time corresponding to time, krFor the recovery coefficient of infiltration, s-1。
4. The water quantity and water quality simulation calculation method of the low-influence development facility according to claim 2, characterized in that: the method for solving the earth surface confluence by adopting a nonlinear reservoir method comprises the following steps:
the surface runoff calculation formula is as follows:
in the formula: a is the area of the catchment area, m2(ii) a n is the Manning coefficient of the catchment area; w is the characteristic width of the catchment area, m; s is the gradient of the catchment area, d is the surface water depth m; dsThe surface depression depth is m;
the calculation formula of the surface water depth along with the time is as follows:
in the formula: d is the surface water depth m; i is rainfall intensity, mm/s; e is evaporation intensity, mm/s; f is the infiltration rate, mm/s; q is the runoff, mm/s.
5. The water quantity and water quality simulation calculation method of the low-influence development facility according to claim 2, characterized in that: the method for calculating the transmission process of the canal water flow and the water quality by adopting the Masjing root method comprises the following steps: the tank storage equation is adopted to replace a momentum equation, the water balance equation is adopted to replace a continuity equation, and the calculation formula is as follows:
in the formula: v is the tank storage amount, m3(ii) a I is the inflow, m3S; q is the flow rate, m3S; Δ t is the calculation step length, s; i and i-1 represent the current time, respectivelyAnd the physical quantity K, X at the previous moment are respectively the Mas Jing root parameters, and have no specific physical significance;
the following equations 6 and 7 are solved:
Qi＝CXIi+CYVi-1 (8)
wherein CX and CY are K, X and delta t functions, and the calculation formula is as follows:
the limiting conditions are as follows:
the relation is obtained from the constraint:
the above is a single river reach calculation formula, and for the multi-river reach case, K/N (N is the number of sub-river reach) is used as a new K value to participate in the calculation.
6. The water quantity and water quality simulation calculation method of the low-influence development facility according to claim 2, characterized in that: the calculation method of the modified Puls model adopted in the transmission process of the canal water flow and the water quality comprises the following steps: the modified PULS model, namely a horizontal pool model, adopts a finite difference format, couples a momentum equation expressed by experience, and calculates the pipeline outflow by giving an inflow process line and a regulation-outflow relation curve;
the continuity equation is:
in the formula:
is the average out-flow, m, over a time step3/s；
Is the average incoming flow, m, over a time step3S; l is the length of the pipeline, m; delta A is the variation of the cross-sectional area of the pipeline, m2(ii) a Delta S is the pipeline regulation and storage variation; Δ t is the time step, s;
assuming that the flow rate varies linearly in time steps, the above equation can be written as:
in the formula: si+1For regulating the storage capacity, m, of the pipeline at the next moment3；SiFor regulating the storage capacity, m, of the pipeline at the present moment3；Qi+1For the next moment of the pipeline outlet flow, m3/s；QiM is the current time of the pipeline outlet flow3/s；Ii+1For the next moment of the pipe inflow, m3/s；IiM is the current pipe inflow3/s；
Si+1And Qi+1The unknown number is the unique unknown number calculated by utilizing a storage-outflow relation curve, and the storage-outflow relation curve is calculated by adopting a Manning formula.
7. The water quantity and water quality simulation calculation method of the low-influence development facility according to claim 2, characterized in that: the method for calculating the accumulation amount of the surface runoff pollutants by the exponential accumulation method comprises the following steps: the basic equation is as follows:
in the formula: b is the accumulated amount of pollutants, kg/hm2；BmaxIs the maximum cumulative amount of pollutants, kg/hm2；KBIs an exponential cumulative coefficient of contamination, day-1(ii) a t is the cumulative time, day.
8. The water quantity and water quality simulation calculation method of the low-influence development facility according to claim 2, characterized in that: the method for calculating the scouring amount of the surface runoff pollutants by the exponential scouring method comprises the following steps: the basic equation is as follows:
mB(t)＝mB(0)e-kt (17)
W(t)＝mB(0)-mB(t)＝mB(0)(1-e-kt) (18)
in the formula: w (t) is the flushing amount of the pollutants at the time t, kg; m isB(0) Is the initial cumulant of the earth's surface, kg; m isB(t) is the earth surface cumulant at the moment t; kg; k is an index coefficient, h,
the above equation is obtained by integrating equation (19).
In the formula: w is the rate of flushing, kg/h,
since k is related to the radial flow rate, it can be expressed as equation (20),
wherein: kWIs the coefficient of erosion, mm-1(ii) a q is catchment areaRunoff, mm/h; n is a radical ofWIs the scouring index.
Thus, the formula (21) can be obtained,
9. the water quantity and water quality simulation calculation method of the low-influence development facility according to claim 2, characterized in that: the method for calculating the scouring amount of the surface runoff pollutants by the EMC scouring method comprises the following steps: the scouring concentration in the runoff scouring process is regarded as the same value, namely the field average concentration.
10. The water quantity and water quality simulation calculation method of the low-influence development facility according to claim 1, characterized in that: the second step comprises the following specific steps:
(1) calculating the water storage stagnation and transmission process of the low-influence development facility by adopting a water continuity equation;
the low-impact development facility consists of five structural layers, which are respectively: the surface course, the layer of mating formation, soil layer, regulation layer and evacuation bed course, each structural layer water yield computational formula is:
surface layer:
a soil layer:
a storage layer:
paving a layer:
and (3) emptying the cushion layer:
in the formula: is the face layer void fraction; d1 is surface water depth, m; i is the rainfall of the surface layer, m/s; q0 is the runoff of the catchment area merging into the surface layer, m/s; e1 is the amount of evaporation of the surface layer, m/s; f1 is the infiltration amount from the surface layer to the soil layer, m/s; q1 is surface layer outflow rate, m/s; d2 is soil layer thickness, m; the water content of the soil layer; e2 is the evapotranspiration of the soil layer, m/s; f2 is the infiltration amount from the soil layer to the storage regulating layer, m/s; adjusting the porosity of the storage layer; d3 is the depth of reservoir water, m; e3 is the evapotranspiration of the storage regulating layer, m/s; f3 is the infiltration amount from the regulation layer to the lower soil (assuming the saturated hydraulic conductivity of the lower soil), m/s; q3 is blind pipe outlet flow rate, m/s; phi is a4The porosity of the cushion layer is emptied; d4M is the depth of the water of the cushion layer; f. of4The infiltration amount from the soil layer to the emptying cushion layer is m/s; e.g. of the type4In order to exhaust the evapotranspiration amount of the cushion layer, m/s; q. q.s4M/s to evacuate the outflow of the cushion layer; d4To thickness of the paving layer, θ4The water content of the soil layer; e.g. of the type5The evaporation capacity of the pavement layer is m/s; f. of5M/s is the output flow of the pavement layer;
(2) calculating the water quality reduction process of the low-impact development facility by adopting a pollutant first-stage degradation method;
in the water quality calculation, the pollutants of each structural layer are assumed to be completely mixed, the removal effect of the pollutants is reflected by setting a first-level degradation coefficient of each structural layer, and the calculation formula is as follows:
in the formula: v is the water quantity of the structural layer, m 3; c is the water quality concentration in the structural layer, mg/L; c. C0The inflow concentration of the structural layer is mg/L; q. q.s0The inflow rate of the structural layer is m/s; q is the structural layer outlet flow, m/s; k is the first-order degradation coefficient of water quality in the structural layer, s-1。
11. The water quantity and water quality simulation calculation method of the low-impact development facility according to claim 10, characterized in that: in the second step, the surface runoff is calculated by using a Manning formula, and if the width of the surface runoff is far greater than the depth of the surface runoff, the surface runoff is calculated by derivation according to the following formula:
in the formula: n is1The coefficient of surface roughness; s1Is a slope; w1Is the flow length, m; d1Surface depression depth, m; a. the1Is the area of the surface layer, m2；
The evapotranspiration calculation formula of the surface layer, the soil layer and the storage regulating layer is as follows:
e1＝min[E0(t),d1/Δt] (26)
e2＝min[E0(t)-e1,(θ2-θWP)D2/Δt] (27)
in the formula: e0(t) is the potential evaporation capacity of the system at the moment t, m/s; thetaWPPorosity corresponding to wilting points;
when the water content of the soil layer is lower than the porosity of the wilting point, the soil layer does not evaporate; if the soil layer is saturated, no evapotranspiration exists in the storage layer; if the soil layer and the storage regulating layer have surface layer infiltration amount, no evapotranspiration occurs;
the formula for calculating the infiltration amount from the soil layer to the storage regulating layer is as follows:
in the formula: k2SIs full of soil layerAnd hydraulic conductivity, m/s; HCO is the attenuation coefficient in a relation curve of hydraulic conductivity and water content; thetaFCThe field water capacity;
the blind pipe outlet flow calculation formula is as follows:
in the formula: h is3Water head above the blind pipe, m; c3DThe blind pipe outflow coefficient; eta3DBlind tube outflow index.
The water head calculation formula above the blind pipe is as follows:
in the formula: d3DThe embedding height of the blind pipe in the storage layer is set;
the pavement layer has the calculation formula as follows:
in the formula: d4To thickness of the paving layer, θ4The water content of the soil layer; e.g. of the type5The evaporation capacity of the pavement layer is m/s; f. of5M/s is the output flow of the pavement layer;
the empty pad calculation formula is:
in the formula: phi is a4The porosity of the cushion layer is emptied; d4M is the depth of the water of the cushion layer; f. of4The infiltration amount from the soil layer to the emptying cushion layer is m/s; e.g. of the type4In order to exhaust the evapotranspiration amount of the cushion layer, m/s; q. q.s4M/s to evacuate the outflow of the mat.
12. The water quantity and water quality simulation calculation method of the low-influence development facility according to claim 1, characterized in that: and thirdly, selecting a certain full-year rainfall as continuous rainfall data, simulating the current working condition under the same rainfall condition and the production confluence condition and the pollution load condition of the low-influence development facility design scheme, calculating the annual runoff total control rate and the annual pollutant load reduction rate, and analyzing the target accessibility of the scheme.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110835175.4A CN113836758A (en) | 2021-07-23 | 2021-07-23 | Water quantity and water quality simulation calculation method for low-influence development facility |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110835175.4A CN113836758A (en) | 2021-07-23 | 2021-07-23 | Water quantity and water quality simulation calculation method for low-influence development facility |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113836758A true CN113836758A (en) | 2021-12-24 |
Family
ID=78962880
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110835175.4A Pending CN113836758A (en) | 2021-07-23 | 2021-07-23 | Water quantity and water quality simulation calculation method for low-influence development facility |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113836758A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115017727A (en) * | 2022-06-28 | 2022-09-06 | 河海大学 | Sewage collection simulation method based on Masjing root method |
-
2021
- 2021-07-23 CN CN202110835175.4A patent/CN113836758A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115017727A (en) * | 2022-06-28 | 2022-09-06 | 河海大学 | Sewage collection simulation method based on Masjing root method |
| CN115017727B (en) * | 2022-06-28 | 2023-04-21 | 河海大学 | Sewage collection simulation method based on Ma Sijing root method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109492299B (en) | Water resource simulation method based on SWMM and MODIflow coupling | |
| CN109492259B (en) | Urban hydrologic simulation system | |
| Nile et al. | An evaluation of flood mitigation using a storm water management model [SWMM] in a residential area in Kerbala, Iraq | |
| CN107239657B (en) | Object-oriented hydrodynamics modeling element management method | |
| Ren et al. | Evaluating the stormwater management model to improve urban water allocation system in drought conditions | |
| Her et al. | A new framework for modeling decentralized low impact developments using Soil and Water Assessment Tool | |
| Lancia et al. | Hydrogeological constraints and opportunities for “Sponge City” development: Shenzhen, southern China | |
| CN112084671B (en) | Urban time-varying gain rainfall-runoff process simulation calculation method | |
| Ben-Daoud et al. | The use of low impact development technologies in the attenuation of flood flows in an urban area: Settat city (Morocco) as a case | |
| Turco et al. | Modelling the hydraulic behaviour of permeable pavements through a reservoir element model | |
| CN113836758A (en) | Water quantity and water quality simulation calculation method for low-influence development facility | |
| CN114676473A (en) | Green infrastructure spatial layout optimization method based on artificial intelligence algorithm | |
| CN112663760A (en) | LID measure-based urban rainwater runoff regulation and control method | |
| Maurer | Geohydrology and simulated response to ground-water pumpage in Carson Valley, a river-dominated basin in Douglas County, Nevada, and Alpine County, California | |
| Zhang et al. | Restoration of urban water environment landscape system and SWMM technology integration in water-scarce cities | |
| Barkdoll et al. | Stormwater low-impact development: a call to arms for hydraulic engineers | |
| Shamsi | Modeling rain garden LID impacts on sewer overflows | |
| Douglas et al. | Characterisation of urban streams and urban flooding | |
| CN113006255B (en) | Early warning method for rainwater accumulation in sponge city | |
| CN111982780B (en) | Method for measuring and calculating relation between urban new district planning underlying surface and old underlying surface | |
| KR101181304B1 (en) | Simulation of water independence in the ubiquitous city | |
| CN111999228B (en) | Urban new area infiltration measuring and calculating method | |
| Kumar et al. | Infiltration Rate Assessment of Experimental Rain Garden Using Conventional Models and Machine Learning Algorithms | |
| Bradford et al. | Matching rainwater harvesting strategies with ecological flow needs | |
| CN109002740A (en) | Island rain-flood resources effective utilization system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |