CN-122020783-A - Construction position and scheduling scheme optimization method for resisting upstream effect of salt tide

CN122020783ACN 122020783 ACN122020783 ACN 122020783ACN-122020783-A

Abstract

The invention relates to the technical field of hydraulic engineering planning and operation management, and discloses a construction position and scheduling scheme optimization method for resisting the upstream tracing effect of salt tide, which comprises the steps of obtaining basic hydrodynamic force and geological data of river mouth of a river basin, and removing an unstable area to determine the feasible construction range of a tide blocking gate; establishing a two-dimensional numerical simulation model of the estuary, calibrating by using measured data to obtain an effective model, setting a plurality of candidate positions in the model, simulating a salt tide tracing process, determining an optimal construction position by comparing salinity indexes, setting a gate at the optimal position, simulating a plurality of scheduling working conditions, and determining an optimal scheduling scheme. According to the invention, through coupling space site selection and time scheduling optimization, the salt blocking efficiency of different section and average value threshold scheduling modes is quantitatively evaluated by utilizing numerical simulation, and the salt water channel is accurately cut off in the high water level period of the flood tide, so that the average salinity of the estuary area and the salinity of key measuring points are reduced, and the estuary fresh water resource safety is effectively ensured.

Inventors

RUAN WEIFANG
WANG XIBIN
LI SHIEN
Lin Xiutan

Assignees

福建省水利水电科学研究院

Dates

Publication Date: 20260512
Application Date: 20260113

Claims (10)

1. The construction position and scheduling scheme optimization method for resisting the upstream effect of salt tide is characterized by comprising the following steps of: Step S1, acquiring basic hydrodynamic parameter data of a river mouth of a region traced by a salty tide, acquiring geological survey data of the river mouth, and determining a feasible construction range for constructing a tidal barrier according to the geological survey data of the river mouth; S2, establishing a two-dimensional numerical simulation model of the estuary, setting model parameters by using the basic hydrodynamic parameter data, and comparing and calibrating the two-dimensional numerical simulation model of the estuary by using the measured salinity data until the simulation error meets the preset requirement to obtain an effective two-dimensional numerical simulation model of the estuary; S3, setting a plurality of tide gate candidate positions in the two-dimensional numerical simulation model of the estuary by utilizing the two-dimensional numerical simulation model of the effective estuary, respectively simulating a salt tide tracing process, and determining an optimal tide gate construction position from the feasible construction range by comparing average salinity of an estuary area with salinity of key measuring points; And S4, setting a gate boundary at the construction position of the optimal tidal barrier, simulating flow fields and salinity fields under various scheduling working conditions, and determining an optimal tidal barrier scheduling scheme by comparing average salinity of estuary areas and salinity of key measuring points.
2. The method for optimizing a construction position and a scheduling scheme for resisting a salt tide tracing effect according to claim 1, wherein in step S1, the basic hydrodynamic parameter data includes: geographic topography data comprising boundary coordinates of land shorelines of the underwater topography Gao Chengji measured in the estuary water area; Hydrodynamic boundary data comprising a time series of tide levels at open sea boundaries and runoff flow at boundary upstream of the inland river; and fluid physical attribute parameters including coriolis force parameters, gravitational acceleration, reference density of water, actual density of water, atmospheric pressure, surface wind field data, bed surface roughness data, and seawater salinity data.
3. The construction position and scheduling scheme optimizing method for resisting upstream tracing effect of salt tide according to claim 1, wherein in step S1, the specific step of determining a feasible construction range for constructing a tide gate comprises: Acquiring riverbed stratum structure data, fault distribution data and geomechanical parameters according to the estuary geological survey data; Estimating the foundation bearing capacity and stability of the river bed, and analyzing the dredging change trend of the river bed by combining the historical river bed evolution data; and removing unstable areas with insufficient foundation bearing capacity, movable faults and violent flushing states in the river mouth river basin range, and screening out areas with stable geological conditions as the feasible construction range.
4. The method for optimizing a construction position and a scheduling scheme for resisting an upstream tracing effect of a salt tide according to claim 1, wherein in step S2, a grid is constructed by adopting a multi-scale nesting or local encryption technology when a two-dimensional numerical simulation model of a estuary is established; And in the range of five hundred meters to one kilometer upstream and downstream of the preset tide gate candidate axis, the grid resolution is transited from the coarse grid of the open sea area to the fine grid by encryption.
5. The method for optimizing a construction position and a scheduling scheme for resisting an upstream tracing effect of a salt tide according to claim 1, wherein the estuary two-dimensional numerical simulation model comprises a hydrodynamic calculation module and a salinity migration diffusion calculation module; the hydrodynamic force calculation module is based on an unsteady shallow water equation set of two-dimensional depth average, and the momentum equation of the unsteady shallow water equation set comprises: A coriolis force term, a water level gradient term, an atmospheric pressure gradient term, an inclined pressure term generated by a density gradient, a water surface wind stress term, a bed surface bottom friction stress term, a wave radiation shear stress term and a horizontal vortex viscosity stress term; The salinity migration and diffusion calculation module is based on a substance transportation equation, and the flow velocity field and the total water depth calculated by the hydrodynamic calculation module are utilized to simulate the convection and diffusion processes of salinity in the water body.
6. The method for optimizing a construction position and a scheduling scheme for resisting an upstream tracing effect of a salt tide according to claim 1, wherein in step S2, the specific step of comparing and calibrating the estuary two-dimensional numerical simulation model to obtain the effective estuary two-dimensional numerical simulation model comprises the following steps: setting soft start time, and linearly increasing boundary driving force from zero to an actual value until a flow field and a salinity field of the estuary two-dimensional numerical simulation model reach a dynamic balance state; comparing the simulated tide level, the simulated flow velocity and the simulated salinity process line output by the estuary two-dimensional numerical simulation model with measured data; And adjusting the bed surface roughness, the vortex viscosity coefficient and the horizontal salinity diffusion coefficient in the estuary two-dimensional numerical simulation model until the Nash efficiency coefficient of the simulated tide level and the actually measured tide level is larger than a preset threshold value and the relative error of the simulated salinity and the actually measured salinity is smaller than a preset proportion.
7. The method for optimizing a construction position and a scheduling scheme for resisting an upstream tracing effect of a salt tide according to claim 1, wherein in step S3, the average salinity of the estuary area is the average salinity of all grid nodes in a water area range of a selected estuary in the two-dimensional numerical simulation model of the estuary; the salinity of the key measuring points is the salinity time-varying process of the sensitive position in the estuary two-dimensional numerical simulation model; The standard for determining the construction position of the optimal tidal barrier is that the average salinity of the estuary area is selected to be reduced to the maximum, and the salinity of the key measuring points can be controlled to be below the national control standard.
8. The method for optimizing a construction position and a scheduling scheme for resisting a salt tide tracing effect according to claim 1, wherein in step S4, the plurality of scheduling conditions includes a conventional peak-shifting scheduling mode, and a control strategy of the conventional peak-shifting scheduling mode is as follows: identifying a highest and a lowest tide level value during the annual tide level; when the real-time tide level reaches the highest tide level value, limiting the opening degree of the gate to a half-open state; When the real-time tide level is the lowest tide level value, setting the gate opening to be in a full-open state; for real-time tide levels between the highest and the lowest tide level values, a gate opening is calculated using a linear interpolation function.
9. The method for optimizing a construction position and a scheduling scheme for resisting a salt tide tracing effect according to claim 1, wherein in step S4, the plurality of scheduling conditions includes a reverse peak-staggering scheduling mode, and a control strategy of the reverse peak-staggering scheduling mode is as follows: when the real-time tide level reaches the highest tide level value, setting the opening of the gate to be in a fully closed state; When the real-time tide level is the lowest tide level value, setting the gate opening to be in a full-open state; For real-time tide levels between the highest and lowest tide level values, the gate opening decreases linearly with increasing tide level.
10. The method for optimizing a construction position and a scheduling scheme for resisting a salt tide tracing effect according to claim 1, wherein in step S4, the plurality of scheduling conditions includes an average threshold scheduling mode, and a control strategy of the average threshold scheduling mode is as follows: Calculating the average value of the tide level in the simulation period as a control threshold value; Judging the relation between the real-time tide level and the tide level average value in each time step of the estuary two-dimensional numerical simulation model: If the real-time tide level is larger than the average tide level, judging that the tide-rising salt water invasion high risk period is carried out, and setting the opening of the gate to be in a fully closed state; If the real-time tide level is smaller than the average tide level, judging that the tide falls or the low water level period, and setting the opening of the gate to be in a full-open state; And comparing the mean value threshold scheduling modes to determine the optimal tide gate scheduling scheme.

Description

Construction position and scheduling scheme optimization method for resisting upstream effect of salt tide Technical Field The invention relates to the technical field of hydraulic engineering planning and operation management, in particular to a construction position and scheduling scheme optimization method for resisting a salt tide tracing effect. Background River mouth areas are used as crossing zones of rivers and oceans, and are frequently traced to salty tides under the dual effects of runoffs and tide. The invasion of the high salinity water body threatens the fresh water resource supply of coastal cities and the safety of an estuary ecosystem, and the construction of a tide gate is a common engineering measure for blocking the backtracking of salty tides and guaranteeing the fresh water resource of inland rivers at present. In the existing tidal stop gate engineering planning and design process, the selection of construction positions and the formulation of operation scheduling schemes are often in a relatively fractured state. Under the general condition, the site selection mainly focuses on engineering economic indexes such as river terrain, construction conditions or land sign shifting, and the like, and the physical barrier difference of different section positions on salinity migration and diffusion in a complex hydrodynamic environment is less deeply quantized. The site selection mode of the water power salt resistance effect is neglected due to the convenience of the implementation of the bias engineering, so that the gate has a physical barrier function after being built, but the kinetic energy of salt tide cannot be maximally weakened by utilizing the river topography. Meanwhile, the site selection method simply relying on the hydraulic index sometimes easily ignores the geological risk of complex estuaries, and if a hydraulic building is built in a soft foundation area with active faults or severe erosion and deposition, the long-term potential safety hazard is brought. In addition, in the aspect of operation management of the tide gate, the existing scheduling strategy is mostly dependent on manual experience or simple constant water level control. Conventional scheduling often adopts fixed switch gate time or single water level threshold value, and lacks a dynamic optimization mechanism based on refined numerical simulation. The rough scheduling mode is difficult to accurately capture the key time period with the biggest invasion flux of the salty tide, can not effectively cut off the salt water supply in the flood tide period and fully utilize the radial pressure salty water in the falling tide period, so that the salinity reduction effect of the estuary area is poor when the salty tide is encountered, and the water supply safety of the key water intake is difficult to be guaranteed in all weather. Therefore, there is a need for an optimization method that can systematically couple geologic security constraints, spatial site selection optimization, and time scheduling strategies. Disclosure of Invention Aiming at the defects of the prior art, the invention provides a construction position and scheduling scheme optimization method for resisting the tracing effect of a salt tide, which solves the problems that the salinity control effect of a estuary area is not ideal and the water quality of a key water intake is difficult to stably reach the standard due to improper site selection layout or rough scheduling strategy when the existing tide gate engineering is used for coping with strong salt tide invasion. The invention aims to realize the aim by adopting the following technical scheme that the construction position and scheduling scheme optimization method for resisting the upstream tracing effect of salt tide comprises the following steps: Firstly, basic hydrodynamic parameter data of a river mouth of a region traced by a salty tide are obtained, simultaneously, geological survey data of the river mouth are obtained, and a feasible construction range for constructing a tidal barrier is determined according to the geological survey data of the river mouth. Secondly, establishing a two-dimensional numerical simulation model of the estuary, setting model parameters by using basic hydrodynamic parameter data, and comparing and calibrating the two-dimensional numerical simulation model of the estuary by using measured salinity data until simulation errors meet preset requirements, so as to obtain an effective two-dimensional numerical simulation model of the estuary. And then, setting a plurality of tide gate candidate positions in the model by using the effective estuary two-dimensional numerical simulation model, respectively simulating the upstream process of the salt tide, and determining the optimal tide gate construction position from the feasible construction range by comparing the average salinity of the estuary area with the salinity of the key measuring points. And finally, setti