CN107516172A

CN107516172A - Salty tide influences area and robs light Emergency water supply dispatching method of storing fresh water

Info

Publication number: CN107516172A
Application number: CN201710785760.1A
Authority: CN
Inventors: 贺新春; 汝向文; 丁波; 郑江丽; 张丽; 王凌河
Original assignee: Pearl River Hydraulic Research Institute of PRWRC
Current assignee: Pearl River Hydraulic Research Institute of PRWRC
Priority date: 2017-09-04
Filing date: 2017-09-04
Publication date: 2017-12-26

Abstract

It is related to salty tide influence area and robs light Emergency water supply dispatching method of storing fresh water, comprises the following steps：S1, integrated Zhujiang Estuary network of waterways entirety salty tide mathematical modeling, accurately to determine salinity border outside lock, fine formulation sluice operation scheme in the joint lock pump group's combined dispatching of delta；S2, structure rob light Emergency water supply scheduling model of storing fresh water based on sluice creek Reservoir Pump Station joint debugging, including sluice robs that light, creek is stored fresh water, reservoir adjusts salty and pumping plant to supply light four modules；The expression-form of model includes object function and constraints；S3, establish salty tide influence area rob light Emergency water supply dispatching effect evaluation index system of storing fresh water, that is, rob light evaluation index system of storing fresh water；S4, using salty tide influence area rob light Emergency water supply dispatching method of storing fresh water, determine that light scheme of storing fresh water is robbed in region.Effective guarantee of the present invention salty tide influences regional dry season water supply security, belongs to water supply security safeguards technique field.

Description

Method for emergency water supply scheduling for regions affected by salt tides

Technical Field

The invention relates to a water supply safety guarantee technology in the water supply field, in particular to a dimming and fresh-keeping emergency water supply scheduling technology for guaranteeing drinking water safety in regions affected by salt tides.

Background

The salt tide at the dry season of the Yangtze river estuary is serious, and particularly since the 90 s of the 20 th century, the salt tide is more and more frequent, the range is larger and larger, the intensity is higher and higher, and the time is more and more advanced. The chlorine content of a water body at a water intake exceeds the standard due to upward tracing of salt tides, the water supply safety of the Yangtze river delta area is greatly influenced, the influenced range relates to cities such as Macau, zhu sea, zhongshan, guangzhou and Dongguan, and the influenced population reaches as many as 1500 million people.

In order to deal with the crisis of salt tide, emergency water supply in a 'rush to fresh water and little to fresh' mode is commonly adopted in all the areas of the Zhujiang Delta, namely, the effective surge capacity of the river surge in the water network area is fully utilized, the fresh water is rushed to be introduced through a sluice gate, and the fresh water in the outer river is accumulated to the river surge so as to ensure the safety of drinking water in the dry period. However, the implementation of sluice scheduling is influenced by the water quality change of the water inflow of the inland river, the runoff condition of the external river, the activity of the salt tide and the like, so that in the implementation process of the emergency desalination and desalination emergency scheduling, various problems that the desalination opportunity is difficult to grasp, the desalination process and the desalination process are difficult to coordinate organically, the desalination and desalination efficiency is low and the like are often encountered. How to consider runoff characteristics of the external river and the activity rule of the salt tide, fully play the scheduling function of the water conservancy project of the water network area, and efficiently implement the light and light emergency water supply scheduling, is an important scientific and technological problem to be solved urgently for guaranteeing the safety of drinking water in the Yangtze river delta.

The research of a water gate-river surge-reservoir-pump station joint regulation-based light and light robbing emergency water supply scheduling technology is developed, an optimized scheduling scheme is researched and proposed, the utilization efficiency of the fresh water resources in the water network area of the Yangtze river mouth is improved, the water supply capacity of the area is enhanced, and the method has important significance for guaranteeing the drinking water safety of the Yangtze delta.

Disclosure of Invention

The invention aims to overcome the defects and shortcomings of the traditional water supply scheme in the Zhujiang delta united enclosure, and provides a systematic scheduling optimization scheme by developing key technical research of emergency light-saving and light-saving water supply scheduling based on sluice-river surge-reservoir-pump station joint regulation in a region affected by salt tide, thereby scientifically improving regional water environment and enhancing regional water supply capacity.

In order to achieve the purpose, the invention adopts the following technical scheme:

the core of the method for dispatching the emergency water supply for saving fresh water and saving fresh water in the regions affected by the salt tide is a water gate-river surge-reservoir-pump station joint dispatching model, and the method is specifically realized by the following steps:

s1, integrating a mathematical model of the integral salt tide of the Zhujiang estuary-river network so as to more accurately determine the salinity boundary outside the gate and more finely establish a water gate scheduling scheme in the united scheduling of the pumping group of the delta-linked enclosure gate.

S2, establishing a water gate-river surge-reservoir-pump station joint regulation-based light and salt emergency water supply scheduling model, which mainly comprises four technical modules of water gate light and salt emergency, river surge light and salt emergency, reservoir salt emergency, pump station light and salt emergency and comprises a target function and constraint conditions.

And S3, establishing a light-saving and light-saving emergency water supply dispatching effect evaluation index system in the region influenced by the salt tide, namely the light-saving and light-saving evaluation index system.

And S4, determining a regional desalination and desalination scheme by using a desalination and desalination emergency water supply scheduling method in the region affected by the salt tide.

Preferably, in S1, the mathematical model of the integral salt tide between the entrance of the pearl river and the river network comprises the following steps:

s11, model building

In order to realize the delta-coupled enclosure gate pump group scheduling under the overall regulation and control of the upstream reservoir, the simulation and coupling of the coastal estuary, the delta integral river network and the coupled enclosure inland river water inrush dynamic water quality regulation and control process are combined to construct a complete Zhujiang estuary-river network-coupled enclosure water flow salinity simulation and gate pump group scheduling model. Considering the complexity of the time-space variation of the Zhujiang estuary salt tide and the importance of the external river salinity to the gate pump scheduling rule determination, the model of the water flow and the salinity adopts an estuary-river network integral three-dimensional salt tide mathematical model, and a typical linkage gate pump group scheduling model is coupled with the mathematical model.

S12, model composition

(1) Calculation equation

The basis of the three-dimensional salt tide mathematical model is an N-S equation of Reynolds averaging, which comprises the turbulence influence and density change and simultaneously comprises a salinity and temperature balance equation:

in the formula: x is a radical of a fluorine atom _i And x _j A Cartesian coordinate system; ρ is the density of water; c. C _s Is the propagation velocity of sound in seawater; u. u _i And u _j Are respectively x _i And x _j A velocity component of the direction; omega _ij Is the Krebs tensor; p is pressure; g is a radical of formula _i Is a gravity vector; v _T Is the turbulent viscosity coefficient; delta _ij Is a crohnac function; k is turbulent kinetic energy; s and T respectively refer to temperature and salinity; d _T And D _S Respectively indicating the relevant temperature and salinity diffusion coefficients; t refers to time; the SS is the respective source and sink item.

(2) Boundary condition

For hydrodynamic calculation, corresponding position water level change sequences are respectively adopted at the upstream and the downstream of the model; for water quality calculation, salinity is the main predicted pollutant and is set as a salinity variation sequence of corresponding positions.

(3) Initial conditions

And performing vertical interpolation on the salinity value according to the hydrodynamic condition at the initial moment and the empirical rule of salinity distribution of each layer of the river mouth of the Zhujiang river by utilizing the surface salinity value obtained by inversion of satellite remote sensing data to obtain a salinity initial field required by calculation.

S13, model calculation

The hydrodynamics module integrates momentum and mass conservation equations by adopting an alternate direction implicit iteration method, and solves a generated mathematical matrix by adopting a double-precision scanning method.

Preferably, in S2, the light-saving and light-saving emergency water supply scheduling model based on sluice-river-reservoir-pump station joint regulation is implemented as follows:

s21, structural mode

In order to realize the purpose of saving fresh water and guarantee the safety of drinking water, the whole scheduling process of the model consists of four important links: firstly, a sluice desalination link is adopted, and extra river fresh water is introduced into the connected and enclosed river through sluice scheduling; secondly, in the river surge fresh water accumulation link, the effective surge volume accumulation fresh water of the river surge in the united periphery is utilized; thirdly, a reservoir adjusting and salty link, when the river surge fresh water is insufficient or the chlorine content exceeds the standard in the dry water period, the river surge is subjected to water supplementing adjustment by using the fresh water stored in the reservoir so as to meet the requirements of water quantity and water quality (salinity) of water taken by a water plant; and fourthly, a pumping station is used for supplying fresh water to a water plant by using a water taking pumping station.

S22, expression forms

(1) Principle of calculation

The one-dimensional hydrodynamics mathematical module of the network river area adopts a one-dimensional Saint-Venn equation set, and the equation is as follows:

equation of continuity

Equation of momentum

In the formula: z is the average water level of the section; q, A and B are respectively the section flow, the water passing area and the water surface width; x and t are distance and time; q is side inflow, negative values indicate outflow; beta is a momentum correction coefficient; g is gravity acceleration; s _f For the friction resistance of the slope, the formula of Manning is adopted to calculate S _f ＝g/C ² ，C＝h ^1/6 /n；u _l Is the component of the lateral outflow velocity in the main flow direction per unit flow path.

One-dimensional water quality migration and transformation basic equation:

in the formula: a is the cross-section water passing area; q is the section flow; c is the section pollutant concentration; e _x Is a longitudinal dispersion coefficient; k is the pollutant degradation coefficient, and x and t are the distance and the time.

(2) Boundary condition

According to the boundary position of the constructed model, corresponding water level (flow) data are respectively adopted as hydrodynamic boundaries and corresponding pollutant concentrations (COD and NH) ₃ -N, chlorinity) data as water quality boundary.

(3) Initial conditions

And setting initial water level and water quality calculation conditions within a model range according to the actually measured data of the region.

(4) Solving method

And (3) carrying out discretization on the control equation by using an Abbott six-point hidden format, and alternately calculating the water level and the flow of each grid point in sequence, wherein the corresponding points are h point and Q point respectively.

S23, objective function

The emergency water supply dispatching of the light and light saving is multi-target dispatching and comprises a general target and two sub-targets: the overall goal is that the water supply system meets the raw water shortage minimum of the chlorine content standard; the links of water gate desalination and river surge desalination are respectively targeted to the highest available quantity of inland river surge water body; the pumping station fresh water supply link is targeted to maximize the total amount of fresh water supplied by the pumping station, namely, the longest duration time for meeting the water supply requirement.

(1) General object

The water supply system meets the raw water shortage minimum of the chlorinity standard, and the objective function is as follows:

WD＝min(D-W)

in the formula: WD is the raw water shortage of a water supply system meeting the chlorine content standard; w is the raw water supply quantity meeting the chlorine content standard of a pump station supply water plant after the fresh water in the outer river is stored into the inner river surge or the reservoir; d is the raw water requirement of the water plant.

(2) Water gate desalination and river surge desalination scheduling target

The inland river water inrush level is increased during dispatching, the accumulated fresh water quantity is the most, and the objective function is as follows:

V＝max(V ₀ +Q _into -Q _{Go out} )

In the formula, V is the water storage capacity of the river; v ₀ Initial water storage capacity as a river surge; q _{Go into} 、Q _{Go out} The water inflow of the upstream water inlet sluice and the water outflow of each downstream sluice are adopted.

(3) Pump station fresh water supply and fresh water supply scheduling target

The guarantee time of water supply in the salt period is longest, the standard (lower than 250 mg/L) of the chlorinity is met, the requirement of the water level of a pump station is met, and a comprehensive objective function is as follows:

T _{for supplying to} ＝max(min(T ₁ +T ₂ +…+T _n ))

In the formula: t is _{For supplying to} Supplying water for guaranteeing time during the exceeding of the chlorine content of the Yangtze river; t is ₁ 、T ₂ …T _n And respectively supplying water to each water intake to guarantee time.

S24, constraint conditions

The constraint conditions mainly comprise the aspects of river surge control water level in a river network area, gate boundary water flow calculation, gate hole scheduling number, gate scheduling modes and the like, and specifically comprise the following steps:

(1) River surge water level restraint in river network area

In the formula: z _k,t The water level of the kth section of the river surge in the scheduled time t is determined; z _k,t The lowest limit water level at the kth section of the river surge in the scheduled time t;and scheduling the highest limit water level at the kth section of the river surge in the time t.

(2) Design flow restriction for passing gate

Q _j,t ≤Q _j,max

In the formula: q _j,t The gate passing flow of the jth water gate of the inland river at the moment t is scheduled; q _j,max The overflow capacity is designed for the j-th water gate of inland river surge.

(3) Restriction of gate opening mode

The main considerations in the model are as follows:

(1) the sluice only has two states of full closing and full opening;

(2) in order to avoid the water gate from being opened and closed too frequently, a certain specific opening and closing state of the water gate must be maintained for a certain time;

T _j ≥T _j

in the formula: t is _j The time length for maintaining a certain specific working state (such as the gate is fully opened or fully closed) for the jth water gate of the inland river surge;T _j the shortest time allowed by a certain specific working state is maintained for the inland river surge jth water gate.

(4) Reservoir salt regulation restraint

C _j,t ≤C _j,max

In the formula: c _j,t Dispatching a pollutant (chlorinity) concentration value at the section of the river j at the moment t for ex-warehouse; c _j,max The concentration value of the pollutants (chlorinity) in the j section of the inland river surge is shown.

(5) Pump station water intaking restraint

C _j,t ≤C _j,max

Z _j,t ≥Z _j,min

In the formula: c _j,t The pollutant concentration of the j section of the inland river at the moment t is scheduled; c _j,max Satisfying the pollutant concentration limit value of the pump station operation for the jth section of the inland river surge; z is a linear or branched member _j,t Scheduling the water level of the j section of the inland river at the time t; z is a linear or branched member _j,min And the jth section of the inland river surge meets the water level limit value of the operation of the pump station.

Preferably, in S3, the evaluation index system for the emergency water supply scheduling effect of the fresh water and light water saving in the region affected by the salt tide comprises the following implementation steps:

the aim of the light-weight and light-weight saving dispatching is to guarantee the water supply problem of the regional water plant, and certain indexes are adopted for optimal evaluation aiming at various established schemes. In the analysis of the simulation result, the total operation time of the pump station and the total pumped water amount are used as main evaluation indexes, and other indexes are used for auxiliary evaluation, such as the change of the water level and the chlorine content of the river surge control section is used for evaluating the effect of robbery, and the change of the water storage capacity of the river surge and the change of the water volume of the water intake section are used for evaluating the effect of river surge.

Preferably, in S4, the determination of the regional dimming and desalination emergency water supply scheduling scheme requires that on the basis of the clear regional hydrodynamic and salinity characteristics and the influence of the sluice on the water power and salinity in the enclosure, the discussion of scheduling targets and rules is carried out, different combined scheduling schemes are drawn up, and the evaluation result of the evaluation system established in S3 is combined to carry out balance optimization and final determination.

Compared with the prior art, the invention has the following advantages and effects:

1. the invention provides a concept of a water gate-river surge-reservoir-pump station joint regulation-based fresh water and fresh water emergency water supply scheduling method for a salt tide affected area systematically, fully exerts the functions of water network area river surge regulation and water conservancy project scheduling on the basis of considering the runoff characteristics of the external river and the salt tide activity rule, and performs water gate-river surge-reservoir-pump station joint scheduling.

2. The invention constructs a light and light robbing emergency water supply dispatching model system based on sluice-river-reservoir-pump station joint dispatching, which comprises a sluice light robbing module, a river light storing module, a reservoir salt dispatching module and a pump station light supplying module. The model system overcomes the problems that the desalination opportunity is difficult to grasp, the desalination process and the desalination process are difficult to coordinate organically, the desalination efficiency is low and the like in empirical scheduling, optimizes and determines the key scheduling opportunity of each link, realizes the scheduling targets of the minimum raw water shortage, the maximum available water quantity of the inland river water accumulation and the maximum fresh water supply quantity of a pump station which meet the chlorinity standard, and effectively ensures the water supply safety of a region affected by the salt tide in the dry season.

3. The invention establishes a light-fast and light-slow emergency water supply dispatching effect evaluation index system in the region influenced by the salt tide, and comprehensively and scientifically evaluates and analyzes the setting of a dispatching scheme.

Drawings

FIG. 1 is a schematic illustration of the location of an embodiment of the present invention (with the center bead enclosed).

Fig. 2 is a water lock dilution quantity accumulation diagram of the west river at the water dilution and dilution scheduling stage in the embodiment of the invention.

FIG. 3 is a line of the change process of the section water storage capacity of the Tanzhou water plant in the light saving and impoverishment dispatching stage in the embodiment of the invention.

Fig. 4a to 4d are diagrams of an operation process of a pumping station of a tanaka water plant in a light-saving and light-storing dispatching stage according to an embodiment of the present invention, where 4a corresponds to a first scheme, 4b corresponds to a second scheme, 4c corresponds to a third scheme, and 4d corresponds to a fourth scheme.

Fig. 5a to 5d are diagrams illustrating an operation process of a freehand and thin-storage dispatching stage yuzhou pumping station according to an embodiment of the present invention, where 5a corresponds to a first solution, 5b corresponds to a second solution, 5c corresponds to a third solution, and 5d corresponds to a fourth solution.

Fig. 6 is a diagram of a process of changing the salinity of a section of a showa water plant under four dispatching schedules in an embodiment of the present invention.

FIG. 7 is a diagram of a process of controlling the salty taste of the Feichan mountain reservoir in the stage of the auxiliary reservoir salty taste regulation scheduling according to the embodiment of the invention.

Fig. 8 is a comparison diagram of the change of the salinity of the section of the tanaka water plant in the reservoir salt-adjusting auxiliary dispatching stage in the embodiment of the invention.

Fig. 9 is a comparison diagram of the change of the section water level of the tanaka water plant in the reservoir salt-adjusting auxiliary dispatching stage in the embodiment of the invention.

Detailed Description

The present invention will be described in further detail with reference to examples and drawings, but the embodiments of the present invention are not limited thereto.

The invention discloses a method for dispatching emergency water supply for saving fresh water and saving fresh water in regions affected by salt tides, which integrates a mathematical model of the integral salt tides of a river mouth and a river network of a Zhujiang river and constructs a water saving emergency water supply dispatching model based on joint dispatching of sluice, river surge, reservoir and pump station, and the specific implementation process comprises the following steps:

1. and integrating a mathematical model of the integral salt tide of the Yangtze river estuary-river network so as to more accurately determine the salinity boundary outside the gate and more finely establish a water gate scheduling scheme in the united scheduling of the pumping group of the delta-linked enclosure gate.

(1) Model building

In order to realize the delta-linked enclosure gate pump group scheduling under the overall regulation and control of the upstream reservoir, the offshore estuary, the delta integral river network and the linked inland river water inrush dynamic water quality regulation and control process are simulated and coupled, and a complete Zhujiang estuary-river network-linked enclosure water flow salinity simulation and gate pump group scheduling model is integrally constructed. Considering the complexity of the time-space variation of the salt tide at the river mouth of the Zhujiang river and the importance of the salinity of the outer river to the determination of the gate pump scheduling rule, a mathematical model of the river mouth-river network integrated three-dimensional salt tide is adopted for the model of the water flow and the salinity, and a typical gate pump group scheduling model is coupled with the mathematical model. In the embodiment, the upstream boundary positions of the model are a Makou station, a Sanshui station, a Laoyou station, a Xin shop and a Sisheng station respectively, the downstream boundary positions are taken at the depth lines of about 200m and the like of the open sea, and the calculation range covers the main river channel of the network river area of the Zhujiang delta river, the Badaogoumen of the Zhujiang river estuary and the range of flushing fresh water of the open sea.

(2) Model composition

(1) Calculation equation

in the formula, x _i And x _j A Cartesian coordinate system; ρ is the density of water; c. C _s The propagation velocity of sound in seawater; u. u _i And u _j Are respectively x _i And x _j A velocity component of the direction; omega _ij Is the Krebs tensor; p is pressure; g is a radical of formula _i Is a gravity vector; v _T Is the turbulent viscosity coefficient; delta _ij Is a crohnac function; k is turbulent kinetic energy; s and T respectively refer to temperature and salinity; d _T And D _S Respectively, the relevant temperature and salinity diffusion coefficients; t refers to time; the SS is the respective source and sink item.

(2) Boundary condition

The upstream flow and salinity boundary conditions can both be given by the measured time series of the respective sites, and since the mode calculation range is large enough, the upstream boundary salinity value is a fixed value substantially close to zero, which can be directly given as zero.

The tidal and salinity boundary of the open sea of the downstream boundary has no corresponding measured data, and the setting is difficult. When the depth of the open sea is large, the tide is affected by the land near the shoreThe influence of the form and river runoff is small and can be calculated by a tide harmonic constant. At this time, the seaside tide boundary of the model is calculated by a tide harmonic constant obtained by T/P satellite altimeter data harmonic analysis, including M ₂ 、S ₂ 、N ₂ 、K ₂ 、K ₁ 、P ₁ 、O ₁ 、Q ₁ And checking the boundary conditions according to seasonal changes of the sea level in south China and offshore site data. Because the open sea boundary is arranged far enough away from the estuary and is basically not influenced by dilute water, the boundary condition of salinity can be given a fixed value within a certain simulation calculation period.

(3) Initial conditions

(3) Model computation

The hydrodynamics module integrates momentum and mass conservation equations by adopting an alternate direction implicit iteration method, and solves a mathematical matrix generated by the momentum and mass conservation equations by adopting a double-precision scanning method.

2. Establishing a light and light emergency water supply scheduling model based on sluice-river surge-reservoir-pump station joint regulation, wherein the model mainly comprises four modules of sluice light and water storage, river surge, reservoir salt regulation, pump station light and water supply and the like; the expression form of the model includes an objective function and a constraint condition.

(1) Structural mode

(2) Forms of expression

(1) Principle of calculation

equation of continuity

Equation of momentum

In the formula: z is the average water level of the section; q, A and B are respectively the section flow, the water passing area and the water surface width; x and t are distance and time; q is a side inflow, and a negative value indicates outflow; beta is a momentum correction coefficient; g is gravity acceleration; s _f For the friction resistance to fall, the Manning formula is adopted to calculate S _f ＝g/C ² ，C＝h ^1/6 /n；u _l Is the component of the lateral outflow velocity in the main flow direction per unit flow path.

One-dimensional water quality migration and transformation basic equation:

in the formula: a is the cross-section water passing area; q is the section flow; c is the section pollutant concentration; e _x Is a longitudinal dispersion coefficient; k is a pollutant degradation coefficient; x, t are distance and time.

(2) Data preparation

The shape of the Zhongzhu Liandi uses the actual measurement data in 2010, the achievement of the Changzhou Shuihe Lijing plan in Zhongshan City and the dredging data of 'one river and two gushes' in Zhuhai City.

(3) Boundary condition

In the scheduling model of this embodiment, the maokang surge is selected as the boundary at the upstream of the boundary, and the maokang sluice, the allied rock bay sluice, the lantern mountain sluice, the large-gush-mouth sluice, the guangchang sluice, the flood bay sluice, the rock corner nozzle sluice, and the like are selected as the boundaries at the downstream.

Since no hydrological station exists in the upstream gulf surge, upstream incoming water is calculated according to rainfall in the dry water period; and the downstream adopts the actual measurement of the tide level and salinity data outside each sluice.

(4) Initial conditions

Initial conditions of water quality: the water quality in the enclosure is monitored according to the water quality, the salinity is 30mg/L, the COD is 30mg/L, and NH is generated ₃ N is 1.5mg/L, and before carrying out the desalination and desalination scheduling, the water quality of the river in the united enclosure needs to be improved, so that favorable water quality conditions are provided for the desalination and desalination of the river.

Initial conditions of water level: the initial water level in the enclosure is +/-0 m.

(5) Solving method

And (4) discretizing the control equation by using an Abbott six-point hidden format, and alternately calculating the water level and the flow in each grid point in sequence, wherein the corresponding points are h point and Q point respectively.

(3) Objective function

The emergency water supply dispatching of the light and light saving is multi-target dispatching and comprises a general target and two sub-targets: the overall goal is that the water supply system meets the raw water shortage minimum of the chlorinity standard; the links of water gate desalination and river surge desalination are respectively targeted to the highest available quantity of inland river surge water body; the pumping station fresh water supply link is targeted to maximize the total amount of fresh water supplied by the pumping station, namely, the longest duration time for meeting the water supply requirement.

(1) General object

WD＝min(D-W)

in the formula: WD is the raw water shortage of which the water supply system meets the chlorinity standard; w is the raw water supply quantity of a pump station supply water plant meeting the chlorine content standard after the fresh water of the external river is rush stored in an internal river or a reservoir; d is the raw water requirement of the water plant.

(2) Water gate desalination and river flow desalination scheduling target

V＝max(V ₀ +Q _{go into} -Q _{Go out} )

In the formula, V is the water storage capacity of the river; v ₀ Initial water storage capacity as a river surge; q _Into 、Q _{Go out} The water inflow of the upstream water inlet sluice and the water outflow of each downstream sluice are adopted.

(3) Pump station fresh water supply and fresh water supply scheduling target

T _{for supplying to} ＝max(min(T ₁ +T ₂ +…+T _n ))

In the formula: t is _{For supplying to} Supplying water for the period when the salinity of the Yangtze river exceeds the standard for guaranteeing the time; t is ₁ 、T ₂ …T _n And water supply guarantee time is respectively provided for a water intake of a Tanshou water plant and a water intake of a Yuzhou pump station in the period of the over-standard salinity of the external river.

(4) Constraint conditions

The constraint conditions mainly comprise the aspects of river surge control water level in a river network area, gate boundary water flow calculation, gate hole scheduling quantity, gate scheduling modes and the like, and specifically comprise the following steps:

(1) river surge water level restraint in river network area

The geographical elevation of each area surrounded by the river network area is generally low, and the water inflow from the external river is too high, the water discharge from the sluice is insufficient, so that the water level of part of river surge exceeds the highest limit water level, and the water flow overflows to form waterlogging. Meanwhile, the water level of the inland river water inrush is ensured to meet the requirements of normal production, the water quality, the landscape, the shipping and the bank stability are ensured, and the inland river water inrush level is not lower than the minimum limit water level. Namely:

in the formula: z _k,t The water level of the kth section of the river surge in the scheduled time t is determined; z _k,t The lowest limit water level at the kth section of the river surge in the scheduled time t;and scheduling the highest limit water level at the k-th section of the river surge within the time t.

And (3) controlling the water level of the west irrigation river by the fresh water saving and fresh water storage dispatching: z <0.7m; water level in other rivers in the enclosure: z <0.3m.

(2) Design flow restriction for passing gate

The flow of the water gate can be obtained by calculation through a formula, but the flow of the water gate cannot exceed the design flow of the water gate, otherwise, the flow can only overflow according to the design flow of the water gate. Namely:

Q _j,t ≤Q _j,max

in the formula: q _j,t The gate passing flow of the jth water gate of the inland river at the time t is scheduled; q _j,max And designing the overflowing capacity for the j-th water gate of the inland river surge.

(3) Restriction of gate opening mode

In the actual operation process of the sluice engineering, in order to avoid the occurrence of an unfavorable working state, the opening mode of the sluice often has a plurality of constraints and technical limiting conditions. The main considerations in the model are as follows:

a. the sluice only has two states of full closing and full opening;

b. in order to avoid the water gate from being opened and closed too frequently, a certain specific opening and closing state of the water gate must be maintained for a certain time;

T _j ≥T _j

(4) Reservoir salt regulation restraint

The river surge river course water quality when utilizing the iron stove mountain water storehouse exceeds standard carries out the regulation of draining to satisfy the water supply demand, its constraint condition is:

C _j,t ≤C _j,max

in the formula: c _j,t Dispatching a pollutant (chlorinity) concentration value at the section of the river j at the time t for the reservoir; c _j,max For the first gush of inland riverConcentration limit of contaminant (chlorine content) in j section.

(5) Pump station water intaking restraint

In the process of saving fresh water and storing fresh water, the water quality and the water level of the water intake river reach meet the requirement of pumping station water intake at the same time, namely:

C _j,t ≤C _j,max

Z _j,t ≥Z _j,min

in the formula: c _j,t The pollutant concentration of the j section of the inland river at the moment t is scheduled; c _j,max Meeting the limit value of the concentration of pollutants for the operation of a pump station for the jth section of the inland river surge; z _j,t Scheduling the water level of the j section of the inland river at the time t; z is a linear or branched member _j,min And the jth section of the inland river surge meets the water level limit value of the operation of the pump station.

This time, the pollutant concentration constraint: degree of chlorinity<250mg/L；COD<20mg/L；NH ₃ -N<1.0mg/L。

3. And establishing a light-saving and light-saving emergency water supply dispatching effect evaluation index system in the region influenced by the salt tide, namely the light-saving and light-saving evaluation index system.

The aim of the intermediate bead-bound desalination and desalination scheduling is to ensure the water supply of the regional water plant, and a certain index is also adopted for optimal evaluation aiming at various established schemes. In the simulation result analysis, the total pump station operation time and the total pumping amount are used as main evaluation indexes, and other indexes are used for auxiliary evaluation, such as the change of the water level and the chlorine content of the river surge control section is used for evaluating the effect of robbery, and the change of the water storage capacity of the river surge and the change of the water volume of the water intake section are used for evaluating the effect of river surge.

4. And determining a fresh water saving and fresh water saving water supply scheduling scheme by utilizing a fresh water saving and fresh water saving emergency water supply scheduling technology in the region affected by the salt tide.

(1) Developing scheduling targets and rule formulation on the basis of finding out the influence of the middling pearl-linked surrounding water power and salinity characteristics and the influence of a sluice on the surrounding water power and salinity;

(2) Determining the direction of the light-robbing, light-storing and fresh-water changing of the middle bead united periphery as 'northwest entering and southeast exiting' according to the united periphery water taking and draining pattern;

(3) On the basis of the layout of the enclosure-connected gate, the combined scheduling of the water gates inside and outside the enclosure of the middling pearl is considered, the operation mode of the water gates is changed as little as possible, and the scheduling target is realized with the minimum change;

(4) And combining the evaluation system established in the S3 to carry out balance optimization final determination.

Example base case:

the invention selects the middle bead union as a demonstration engineering experiment site, the west boundary of the research range is from the position below a horse corner sluice connected with a sharpening gate water channel to a flood bay sluice, the east boundary is an east irrigation channel, the most northern end of the research range starts from a Maowan to enter a town of Tanshou, and the south part of the research range is bounded by a rock corner nozzle sluice. The water system of the central bead-enclosed inland river network is densely distributed, the area has certain regulation and storage capacity, and the enclosed inland gates and pumps are numerous, so that convenient conditions are provided for hydraulic scheduling regulation and control; meanwhile, due to the fact that the middle pearl connected with the imminent knife sharpening watercourse has serious salt tide upward, the research on the light-robbing and light-storing emergency water supply scheduling technology in the area is developed, and the method has important significance for guaranteeing the safety of drinking water in the area of the Zhujiang delta and promoting the healthy development of social economy.

The middle pearl is surrounded and located in the towns of the Tanzhou, the plain net river area of the middle pearl is like a water collecting basin, and the rainfall in the east, west and north directions is collected: the catchment area of the township area of the Tanshou is about 127.6km ² The north area from the three villages is about 113.0km ² The produced water is gathered into the Mao Bayong; east Pearl sea has an area of about 99.5km ² The produced water is collected into the interior of the Tanzhou, so that the actual water collecting area of the Tanzhou town is 340.1km ² . The water system in the ballast area is especially developed, the river surge is criss-cross, and the river surge capacity reaches 2946 ten thousand m ³ Wherein the river with width of more than 15m mainly comprises 40 river gushes including thaumata gushes, west irrigation canals, tanzhou gushes, east irrigation canals, three-dipping gushes, shentang gushes, south sand gushes, cobia gushes, two-dipping gushes and sow gushes, and the longest river is the front mountain water channel; in addition, there are 5 short rivers with length less than 0.5km, such as twin-billed, sugar refinery, wild billed, big tip tail and triangle-surrounded billed.

The middle bead is connected with the water gate with the same size and the same number of 20, and the running condition is basically good. The water gate 7 is built on the dry dike of the front mountain river basin, and the water gate with the horsehorn, the river trap, the lantern, the large-gushing-mouth, the Guangchang, the river trap and the river trap from west to east respectively have the functions of blocking tide and draining waterlogging. In addition, the horsehorn sluice has a water diversion function, and the allied rock bay sluice, the lantern sluice and the large-gush-mouth sluice have functions of receiving tide for irrigation, maintaining an internal-gush landscape water body, conducting water and improving a river water environment.

The technical scheme of the embodiment is as follows:

1. plan setting

According to the characteristics of the central bead-linked surrounding water power and water quality, the water body replacement of the internal river gush is completed as soon as possible, so that the water quality of the internal river gush water body reaches the standard, favorable water quality conditions are provided for the fresh water accumulated in the internal river gush, and the water gate desalination, the river gush desalination, the reservoir desalination, the pump station desalination and other scheduling can be implemented on the basis.

(1) Quick-response, light-weight and weak-light-weight

In the research, the pearl-connected surrounding desalination and dilution emergency dispatching idea is adopted, on one hand, when the quality of the water body of the external river is better, the opening height of a diversion gate is improved, the requirement of the open water quality of the gate is lowered, and a high-quality water source of a sharpening door enters the interior of a river to achieve the purpose of desalination; on the other hand, the quantity and the water storage height of the storage river are increased, and the height limit of a gate for discharging the water burst in the water reservoir is improved, so that the purpose of 'fresh water storage' is achieved. Particularly, according to the upward tracing rule and the tide level condition of the salt tide of an external river, the water gate of a horsehorn, the sluice gate of a stone-connected bay, the sluice gate of a lantern and the sluice gate of a large surge port are utilized to guide water to the internal rivers such as a west river, the sluice gate of a stone-connected bay, a large surge, a second surge, a third surge, a south sand surge, a shentang surge and the like, so as to ensure the water supply safety of the middle pearl connection.

On the basis of the arrangement of the central pearl connected enclosure river and the gate pump, in order to ensure the safety of water supply in the enclosure and achieve the dispatching target, the current central pearl connected enclosure robbing light and light emergency dispatching scheme is set as follows:

a. the first scheme is as follows: the fresh water is stored in the west river by the way of water inlet of the horsetail sluice and water discharge of the permanent sluice.

The main scheduling engineering scheduling rules are as follows:

(1) horse-horn sluice:

condition 1: when the salinity of the outer river is less than 250mg/L, the water level in the gate is less than 0.7m, and the water level of the outer river is greater than the water level of the inner river, the gate of the water gate of the horsehorn is opened to feed water, and if one of the three water levels cannot meet the condition 2;

condition 2: when the salinity of the outer river is more than 250mg/L, the salinity in the gate is less than 250mg/L, the water level in the gate is less than 0.7m, and the water level of the outer river is more than the water level of the inner river, the gate of the horsehorn sluice is opened to feed water, and if one of the four water levels cannot meet the requirement, the gate is closed.

(2) A permanent water gate: when the water level of the west irrigation river is higher than the gulf surge water level and the water level of the west irrigation river is higher than 0.5m, opening a permanent sluice gate to discharge water; otherwise, the water gate is closed to ensure that the water gate only goes out but not goes in.

(3) Other six floodgates of west river irrigation: are all in the off state.

(4) Other sluice operation modes are as usual.

b. Scheme II: water is fed through a horseshoe sluice, water is not drained from a permanent sluice, and fresh water is diluted and stored in river bodies of inland rivers such as west rivers, united rock rivers, large flooding, two flooding, three flooding, south sand sluice, shengtang sluice and the like in a drainage mode of sluice such as united rock gulf sluice, large flooding sluice, two flooding, three flooding, south sand flooding, shengtang flooding and the like.

The main scheduling engineering scheduling rules are as follows:

(1) horse-horn sluice:

condition 2: when the salinity of the outer river is more than 250mg/L, but the salinity in the gate is less than 250mg/L, the water level in the gate is less than 0.7m, and the water level of the outer river is more than the water level of the inner river, the gate of the water gate of the horsehorn is opened for water inlet, and if one of the four water levels cannot meet the requirement, the gate is closed.

(2) A permanent water gate: and closing.

(3) Other six floodgates of west river irrigation: when the water level of the west irrigation river is higher than the six inner river surge water levels and the water level of the west irrigation river is higher than 0.5m,

opening six water gates to drain water; otherwise, the gate is closed. Ensure that the sluice gate only goes out but not in.

(4) Other sluice operation modes are as usual.

c. The third scheme is as follows: fresh water is stored in inland river bodies such as west river, united rock bay, large surge, two surge, three surge, south sand sluice, shengtang sluice and the like through water inflow of a horsehorn sluice, united rock bay sluice and united rock bay tail sluice and water drainage of sluice gates such as a large surge, two surge, three surge, south sand surge and shengtang surge.

The main scheduling engineering scheduling rules are as follows:

(1) horse-horn sluice:

(2) A united-rock bay sluice:

condition 1: when the salinity of the external river is less than 250mg/L, the water level in the sluice is less than 0.5m, and the water level of the external river is greater than the water level of the internal river, the sluice of the river of the united rock bay is opened to feed water, and if one of the three cannot meet the condition 2;

condition 2: when the salinity of the external river is more than 250mg/L, but the salinity in the gate is less than 250mg/L, the water level in the gate is less than 0.5m, and the water level of the external river is more than the water level of the internal river, the gate of the allied rock bay is opened to supply water, and if one of the four water levels cannot meet the requirement, the gate is closed.

(3) A permanent water gate: and closing.

(4) A united stone bay tailwater gate: and (4) fully opening.

(5) Other five water gates of the west river: when the water level of the west irrigation river is higher than the water level of the five inner rivers and the water level of the west irrigation river is higher than 0.5m, the five water gates are opened to drain water; otherwise, the gate is turned off. Ensure that the sluice can only go out but not go in.

(6) Other sluice operation modes are as usual.

d. The scheme four is as follows: water is fed through a horsehorn sluice, a stone-connected bay sluice, a lantern sluice and a large surge port sluice, and the sluice such as a large-dipping sluice, a second-dipping sluice, a third-dipping sluice, a south-sand sluice, a shengtang sluice and the like discharges water to dilute and accumulate fresh water in river bodies of rivers such as a west river, a stone-connected bay, a large-dipping surge, a second-dipping surge, a third-dipping surge, a south-sand surge, a shengtang surge and the like.

The main scheduling engineering scheduling rules are as follows:

(1) horse-horn sluice:

(2) United stone bay sluice, lantern sluice and large-opening sluice:

condition 1: when the salinity of the external river is less than 250mg/L, the water level in the sluice is less than 0.5m, and the water level of the external river is greater than the water level of the internal river, the sluice of the allite trap is opened to feed water, and if one of the three cannot meet the condition 2;

condition 2: when the salinity of the external river is more than 250mg/L, the salinity in the gate is less than 250mg/L, the water level in the gate is less than 0.5m, and the water level of the external river is more than the water level of the internal river, the gate of the river-united bay is opened to feed water, and if one of the four water levels cannot meet the requirement, the gate is closed.

(3) A permanent water gate: and closing.

(4) A united stone bay tailwater gate: and (4) fully opening.

(5) West river irrigation five other sluice: when the water level of the west irrigation river is higher than the water level of the five inner rivers and the water level of the west irrigation river is higher than 0.5m, the five water gates are opened to drain water; otherwise, the gate is closed. Ensure that the sluice gate only goes out but not in.

(6) Other sluice operation modes are as usual.

(2) Adjusting salt content in reservoir

The activity of the salty tide in the middle pearl-associated surrounding area is controlled by the runoff, the tide and the sluice, and the influence of the salty tide on the river surge is restrained as much as possible by the sluice in the setting of the fresh water, the fresh water and the fresh water. However, in order to further improve the water supply capacity of the area and meet the water supply requirement, the water diversion regulation of the upstream hot metal furnace mountain water reservoir with large piping can be considered. Through preferably selecting four kinds of light-saving and fresh-keeping gate regulation and control schemes, on the basis of selecting an optimal scheme, the flow of a molten iron furnace mountain water reservoir is introduced for regulation and assistance, and the specific scheme is as follows:

for the preferred dimming and dilution scheme: properly reducing the control opening requirement of the gate, and increasing the chlorine content requirement of the gate at the Malus asiatica sluice and the Union Stone Bay sluice to 300mg/L; the chlorine content requirement at the lantern sluice and the large-surge-opening sluice is increased to 400mg/L, and the water inlet capacity is improved; meanwhile, for the operation scheme of the reservoir: and opening the iron furnace mountain reservoir to adjust the salt at the same time when the water inlet is opened at the water gate of the horsehorn, so as to ensure that the chlorine content of the inland river cannot exceed the standard.

2. Evaluation of effects

(1) Quick-response, light-weight and weak-light-weight

In this study, the problem of water intake in a tanaka water plant and a yuzhou pump station is a difficult point which needs to be considered with great importance. Under the four designed scheduling schemes, the hydraulic conditions of the riverway are inconsistent, so the actual operating conditions of the pumping stations are different. For evaluating the light-weight supply effect, the water supply duration and the water supply amount (see fig. 2, 3, 4a-4d and 5a-5 d) meeting the requirements can be calculated from the perspective of salinity and water level, and the advantages and disadvantages of the evaluation scheme are taken as the basis, and are specifically shown in table 1.

TABLE 1 evaluation chart of the quick-change, light-change and fresh-keeping scheme

Note: thickening in the table is a better scheme

The scheme IV has absolute advantages in the aspect of water supply guarantee of the two water taking sections, and the requirement of water supply is completely guaranteed in the simulation period; the third scheme has good water supply effect guarantee in the aspect of the Tanzhou waterworks, but is slightly insufficient in the aspect of the Yuzhou pumping stations, and the second scheme is opposite to the first scheme, has good water supply guarantee in the aspect of the Yuzhou pumping stations, and has slightly better overall water supply guarantee effect than the second scheme in consideration of the important position of the Tanzhou waterworks; the first scheme has the worst effect, and both water plants cannot be completely guaranteed. And selecting according to the advantages and disadvantages of the simulation results of the schemes, and sequencing the advantages and disadvantages of the middlebox associated surrounding area light-saving and light-saving scheduling schemes into a scheme IV, a scheme III, a scheme II and a scheme I, so that the scheme IV is comprehensively selected as a light-saving and light-saving optimal scheme.

(2) Adjusting salt content in reservoir

For the preferred scheme four, when the water of the external river tide enters 12 months with continuous high salinity, the water supply requirement is difficult to guarantee by only relying on the gate pump scheduling. Therefore, the iron furnace mountain reservoir is introduced for adjusting the salt, and after the water discharging process of the reservoir is adjusted, when the reservoir continuously discharges water between 12 months 1 day and 12 months 7 days (see the attached drawing 7), the water taking requirements of a Tanshou water plant and a Yuzhou pump station can be just met: under the action of gate dispatching, the water of the external river enters the internal river through the gate in the initial stage, so that the water level of the internal river is quickly raised, and the corresponding change of the chlorine content also presents a remarkable ascending trend, but the fresh water regulation function of the Feishan reservoir effectively ensures that the chlorine content of the section of the Tanzhou water plant meets the standard (see figure 8); then the water level in the river is gradually reduced under the continuous water pumping action of the pump station, and the water level is always above the minimum water intake water level limit in the whole process (see figure 9), so that the stable operation of the pump station is ensured. Overall, under the function of adjusting the salt of the Feicheshan reservoir, the preferable scheme of the desalting and storing stage is combined, the problem of water supply during the period that the chlorine content of the Yangtze river continuously exceeds the standard is solved, and the safety of drinking water in the region is fully guaranteed.

According to the method, aiming at the characteristics that the Yangtze river delta influences the runoff and the salt tide of the water network area by the salt tide, the middle-pearl united enclosure is selected as a typical research area, and the light-water-saving and light-saving emergency water supply scheduling model based on sluice-river-reservoir-pump station united scheduling is reasonably feasible. The embodiment provides a fresh water and light storage emergency water supply optimized scheduling technology, and by means of the water gate fresh water control, the river fresh water storage, the reservoir salt regulation, the pump station fresh water supply and other scheduling technologies, the effective surge capacity of the river in the united enclosure and the scheduling function of the water conservancy project are fully exerted, the water supply capacity of the area is enhanced, and the healthy development of social economy is guaranteed.

The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such modifications are intended to be included in the scope of the present invention.

Claims

1. A method for dispatching emergency water supply for fresh water and light water storage in regions affected by salt tides is characterized by comprising the following steps: a light and light saving emergency water supply dispatching model based on sluice-river surge-reservoir-pump station joint dispatching comprises the following steps:

s1, integrating a mathematical model of the integral salt tide of a Zhujiang estuary-river network so as to accurately determine the salinity boundary outside a gate and finely make a water gate scheduling scheme in the united scheduling of a pumping group of a delta united gate;

s2, constructing a light and light emergency water supply scheduling model based on sluice-river surge-reservoir-pump station joint regulation, wherein the light and light emergency water supply scheduling model comprises four modules of sluice light control, river surge light control, reservoir salt regulation and pump station light and light supply; the expression form of the model comprises an objective function and a constraint condition;

s3, establishing a light-robbing and light-storing emergency water supply dispatching effect evaluation index system in the region influenced by the salt tide, namely a light-robbing and light-storing evaluation index system;

and S4, determining a regional dimming and light storage scheme by using a dimming and light storage emergency water supply scheduling method in the region affected by the salt tide.

2. The method for emergency water supply dispatching for fresh water and light water in the regions affected by salt tides according to claim 1, wherein the method comprises the following steps: in the step S1, the mathematical model of the integral salt tide of the Yangtze river estuary-river network comprises the following steps:

s11, model building

In order to realize the delta-coupled enclosure gate pump group scheduling under the overall regulation and control of an upstream reservoir, the simulation and coupling of the offshore estuary, delta integral river network and the coupled enclosure inland river water inrush dynamic water quality regulation and control process are combined, and a complete Zhujiang estuary-river network-coupled enclosure water flow salinity simulation and gate pump group scheduling model is constructed; considering the complexity of the time-space variation of the Zhujiang estuary salt tide and the importance of the external river salinity on the determination of the gate pump scheduling rule, a estuary-river network integral three-dimensional salt tide mathematical model is adopted for the model of water flow and salinity, and a typical linkage gate pump group scheduling model is coupled with the mathematical model;

s12, model construction

(1) Calculation equation

The three-dimensional salt tide mathematical model is based on an N-S equation of Reynolds averaging, including turbulence influence and density change, and simultaneously comprises a salinity and temperature balance equation:

in the formula: x is the number of _i And x _j A Cartesian coordinate system; ρ is the density of water; c. C _s The propagation velocity of sound in seawater; u. of _i And u _j Are respectively x _i And x _j A velocity component of the direction; omega _ij Is the Krebs tensor; p is pressure; g _i Is a gravity vector; v _T Is the turbulent viscosity coefficient; delta _ij Is a crohnac function; k is turbulent kinetic energy; s and T respectively refer to temperature and salinity; d _T And D _S Respectively indicating the relevant temperature and salinity diffusion coefficients; t refers to time; SS is the respective source and sink item;

(2) Boundary condition

For hydrodynamic calculation, corresponding position water level change sequences are respectively adopted at the upstream and the downstream of the model; for water quality calculation, predicting the salinity of pollutants, and setting the salinity change sequence at a corresponding position;

(3) Initial conditions

Utilizing the surface salinity value obtained by inversion of satellite remote sensing data, and then carrying out vertical interpolation on the salinity value according to the hydrodynamic condition at the initial moment and the empirical rule of salinity distribution at each layer of the river mouth of the Zhujiang river to obtain a salinity initial field required by calculation;

s13, model calculation

3. The method for emergency water supply dispatching for fresh water and light water accumulation in regions affected by salt tide according to claim 1, characterized in that: in the step S2, based on a structural mode of a light-water saving and light-storage emergency water supply scheduling model of sluice-river surge-reservoir-pump station joint scheduling, the whole scheduling process of the model comprises four links: firstly, the sluice is used for rushing to dilute, and the outfield fresh water is introduced into the river surge in the enclosure through the sluice scheduling; secondly, the river surge is light, and the river surge in the river is effectively surged and stored with fresh water; thirdly, adjusting the salinity of the reservoir, and when the fresh water of the inland river connected in the dry season is insufficient or the chlorine content exceeds the standard, utilizing the fresh water stored in the reservoir to perform water supplementing adjustment on the inland river to meet the requirements of the water quantity and the salinity of the water quality of water taken by a water plant; and fourthly, a pumping station is used for supplying fresh water, and the water taking pumping station is used for supplying the fresh water accumulated in the inland river to a water plant.

4. The method for emergency water supply dispatching between fresh water and light water in the regions affected by salt tides according to claim 3, wherein the method comprises the following steps: in the step S2, the expression form of the emergency water supply dispatching model based on sluice-river surge-reservoir-pump station joint dispatching is as follows:

(1) Principle of calculation

The one-dimensional hydrodynamics mathematical module of the net river area adopts a one-dimensional Saint-Weinan equation set, and the equation is as follows:

equation of continuity

Equation of momentum

In the formula: z is the average water level of the section; q, A and B are respectively the section flow, the water passing area and the water surface width; x and t are distance and time; q is side inflow, negative values indicate outflow; beta is a momentum correction coefficient; g is gravity acceleration; s _f For the friction resistance to fall, the Manning formula is adopted to calculate S _f ＝g/C ² ，C＝h ^1/6 /n；u _l Is the component of the lateral outflow velocity in the main flow direction on the unit flow;

the one-dimensional water quality migration transformation basic equation:

in the formula: a is the cross-section water passing area; q is the section flow; c is the section pollutant concentration; e _x Is a longitudinal dispersion coefficient; k is the pollutant degradation coefficient; x and t are distance and time;

(2) Boundary condition

According to the boundary position of the built model, corresponding water level data are respectively adopted as hydrodynamic boundaries, and corresponding pollutant concentration data are used as water quality boundaries;

(3) Initial conditions

Setting initial water level and water quality calculation conditions within a model range according to the actually measured data of the region;

(4) Solving method

The control equation is discretized by an Abbott six-point hidden format, and the water level and the flow rate of the control equation are alternately calculated in sequence in each grid point.

5. The method for emergency water supply dispatching for fresh water and light water in regions affected by salt tide according to claim 4, characterized in that: in the step S2, a sluice joint dispatching model objective function of the emergency water supply of the fresh water supply and the fresh water supply is as follows:

(1) General object

The water supply system meets the raw water shortage minimum of the chlorine content standard, and the objective function is as follows:

WD＝min(D-W)

in the formula: WD is the raw water shortage of which the water supply system meets the chlorinity standard; w is the raw water supply quantity meeting the chlorine content standard of a pump station supply water plant after the fresh water in the outer river is stored into the inner river surge or the reservoir; d is the raw water requirement of the water plant;

(2) Water gate desalination and river surge desalination scheduling target

V＝max(V ₀ +Q _{go into} -Q _{Go out} )

In the formula, V is the water storage capacity of the river; v ₀ Initial water storage capacity as a river surge; q _{Go into} 、Q _{Go out} The water inflow of the upstream water inlet sluice and the water outflow of each downstream sluice are obtained;

(3) Pump station fresh water supply scheduling target

The water supply guarantee time in the salt period is longest, the requirement of the salinity standard is lower than 250mg/L, the requirement of the water level of a pump station is met, and the comprehensive objective function is as follows:

T _{for supplying to} ＝max(min(T ₁ +T ₂ +…+T _n ))

In the formula: t is a unit of _{For supplying to} Ensuring the time for supplying water during the period that the salinity of the Yangtze river exceeds the standard; t is ₁ 、T ₂ …T _n And water is supplied to each water intake to guarantee time.

6. The method for emergency water supply dispatching for fresh water and light water in regions affected by salt tide according to claim 4, characterized in that: in the step S2, the water gate joint scheduling model constraint conditions of the emergency water supply for the light water saving and fresh water saving are as follows:

the constraint conditions comprise a river surge control water level in the river network area, gate boundary water flow calculation, gate hole scheduling quantity and a gate scheduling mode, and the constraint conditions comprise the following concrete steps:

(1) River surge water level restriction in river network area

In the formula: z is a linear or branched member _k,t The water level at the kth section of the river surge within the moment t is scheduled;Z _k,t the lowest limit water level at the kth section of the river surge in the scheduled time t;the highest limiting water level at the kth section of the river surge in the scheduling time t;

(2) Design flow restriction for lockage

Q _j,t ≤Q _j,max

In the formula: q _j,t The gate passing flow of the jth water gate of the inland river at the moment t is scheduled; q _j,max Designing the flow capacity of the jth inland river surge water gate;

(3) Restriction of gate opening mode

The following are considered in the model:

(1) the sluice only has two states of full closing and full opening;

(2) in order to avoid the frequent opening and closing of the sluice, a certain specific opening and closing state of the sluice must be maintained for a certain time;

T _j ≥T _j

in the formula: t is _j Maintaining the duration of a certain specific working state for the jth inland river surge water gate;T _j maintaining the shortest allowable time length of a certain specific working state for the jth inland river surge water gate;

(4) Reservoir salt regulation restraint

C _j,t ≤C _j,max

In the formula: c _j,t Dispatching a pollutant concentration value at the section of the river j at the time t for the reservoir; c _j,max The pollutant concentration limit value of the j section of the inland river surge is obtained;

(5) Pump station water intaking restraint

C _j,t ≤C _j,max

Z _j,t ≥Z _j,min

In the formula: c _j,t For scheduling j section of inland river at t momentThe concentration of the contaminant; c _j,max Meeting the limit value of the concentration of pollutants for the operation of a pump station for the jth section of the inland river surge; z _j,t Scheduling the water level of the j section of the inland river at the time t; z _j,min And the jth section of the inland river surge meets the water level limit value of the operation of the pump station.

7. The method for emergency water supply dispatching for fresh water and light water in the regions affected by salt tides according to claim 1, wherein the method comprises the following steps: in step S3, the light-to-light and light-to-light emergency water supply dispatching effect evaluation index system in the region affected by the salt tide specifically comprises the following steps:

the fresh water and light water saving dispatching aims at guaranteeing the water supply safety of the regional water plant, a certain index is adopted for optimal evaluation aiming at various established schemes, and in the analysis of simulation results, the total running time and the total pumping amount of a pump station are adopted as evaluation indexes, and meanwhile, auxiliary evaluation is carried out.

8. The method for emergency water supply dispatching for fresh water and light water in the regions affected by salt tides according to claim 1, wherein the method comprises the following steps: in the step S4, the determination of the regional dimming and dimming emergency water supply scheme requires that on the basis of the clear regional hydrodynamic force, the salinity characteristics and the influence of the sluice on the water dynamic force and the salinity in the enclosure, the discussion of scheduling targets and rules is carried out, different combined scheduling schemes are formulated, and the evaluation result of the evaluation index system established in the step S3 is combined to carry out balance optimization and final determination.