A reservoir ice layer growth and disappearance regulation method and system based on underwater power disturbance

Abstract

This invention discloses a method and system for regulating the formation and dissipation of ice layers in reservoirs based on subglacial hydrodynamic disturbance. The method includes: acquiring initial ice conditions and water temperature profile data; drawing warm water from the ice layer to generate directional flow at the ice bottom, forming an isothermal mixing layer; calculating real-time ice-water heat flux based on the heat balance principle and determining a target value; adjusting the outflow elevation or device power according to the heat flux deviation to regulate the interface heat exchange rate; and dynamically compensating based on meteorological monitoring and feedback. The system consists of hydrodynamic disturbance, elevation adjustment, monitoring, and control modules. This invention establishes a quantitative relationship between heat flux, hydrodynamics, and water temperature, achieving precise, low-consumption, and targeted regulation of ice layer formation and dissipation, effectively solving the problem of ice damage affecting the safe operation of reservoirs in cold regions.

Description

Technical Field

[0001] This invention belongs to the field of ice layer formation and dissipation control technology, specifically relating to a method and system for regulating the formation and dissipation of reservoir ice layers based on subglacial hydrodynamic disturbance. Background Technology

[0002] In winter, the freezing of reservoirs and pumped-storage power stations in high-altitude, cold climate zones poses a significant impact and limitation on water conservancy projects and hydropower generation due to reservoir icing. On the one hand, ice breakage can cause physical damage to hydraulic machinery such as gates and turbines; the adhesion of ice to hydraulic structures and slopes can significantly reduce the cross-sectional area of ​​water flow, thereby greatly reducing the flow capacity and operating efficiency of hydropower generation. On the other hand, in certain specific engineering applications, such as ice transportation during winter, underwater ecological insulation, or counterweighting of specific structures, it is necessary to maintain a stable ice cover layer of a certain thickness.

[0003] From a mechanistic perspective, the formation and melting of ice sheets is a comprehensive result of the energy balance between the ice sheet surface, bottom, and interior. Especially in arid, low-snowfall, and high-radiation plateau lake and reservoir environments, the formation and melting of ice sheets are primarily influenced by ice-water heat flux; that is, heat flux significantly inhibits ice sheet growth or promotes ice sheet melting. Ice-water heat flux is, in turn, significantly constrained by hydrodynamic processes such as vertical turbulent mixing under the ice and planar thermal convection. During the daily operation of large-scale water conservancy facilities such as pumped-storage power stations, strong hydrodynamic processes are typically generated within the reservoir basin, which inevitably affects the freezing or melting of the bottom of the floating ice sheet.

[0004] However, current research on ice condition evolution in cold-region reservoirs and practical ice prevention and disaster reduction engineering still have certain limitations. Existing technologies have not fully clarified the quantitative influence mechanism between hydrodynamic conditions, water temperature distribution, and ice-water heat flux, especially lacking a parameterized scheme for ice-bottom heat flux that comprehensively considers the special climatic conditions at high altitudes. Due to the failure to accurately grasp the quantitative feedback mechanism of different hydrodynamic fields on the heat transfer rate at the ice-water interface, existing ice prevention and disaster reduction measures mostly rely on passive protection or lack targeted open-loop regulation, making it difficult to establish accurate ice condition forecasting models for reservoir areas. Consequently, reservoirs and pumped storage power stations struggle to conduct scientific, precise, and targeted ice generation and dissipation control when facing complex and variable ice hazards during the wintering period.

[0005] Therefore, it is necessary to propose a method and system for regulating the formation and dissipation of reservoir ice based on subglacial hydrodynamic disturbances in order to solve or at least alleviate the above-mentioned defects. Summary of the Invention

[0006] The purpose of this invention is to provide a reservoir ice layer generation and dissipation control system and method based on subglacial hydrodynamic disturbance, in order to solve the problems in the existing technology where the lack of quantitative basis for ice-water heat flux leads to the reliance on blind start-up or passive protection for ice prevention and disaster reduction measures, resulting in low control accuracy, high energy consumption and inability to achieve targeted and precise control.

[0007] To achieve the above objectives, the present invention provides the following technical solution: A method for regulating the formation and dissipation of reservoir ice based on subglacial hydrodynamic disturbance includes the following steps: S1. Obtain the initial state parameters of the target area, wherein the initial state parameters include at least the initial ice condition data and the initial water temperature profile data of the subglacial water body; S2. Based on the initial water temperature profile data, determine a relatively high-temperature water layer, and drive the water in the relatively high-temperature water layer to be transported to a preset outflow position to generate a directional disturbed water flow pointing towards the ice-water interface in the target area; S3. Obtain real-time ice thickness change data and real-time ice layer temperature data of the target area, calculate the real-time ice-water heat flux based on the principle of ice bottom heat balance, and determine the corresponding target heat flux according to the preset ice layer generation and dissipation target. S4. Based on the deviation between the target heat flux and the real-time ice-water heat flux, adjust the relative distance between the preset outflow position and the ice-water interface, and / or adjust the operating power driving the water transport, so as to control the heat exchange rate of the ice-water interface.

[0008] Preferably, the initial ice condition data in step S1 includes the initial ice thickness of the target area before hydrodynamic disturbance and the initial temperature inside the ice layer.

[0009] Preferably, the acquisition of initial water temperature profile data in step S1 specifically includes: taking the center point of the preset outflow position as a reference, deploying temperature chains at multiple monitoring points within the horizontal influence radius generated by the directional disturbance water flow, and using multiple temperature probes fixedly deployed on each temperature chain to simultaneously acquire water temperature data at multiple depth layers in the target area, so as to construct a three-dimensional temperature field array of the subglacial water body.

[0010] Preferably, the step S2 of driving the water in the relatively high temperature water layer to the preset outflow position specifically includes: using a hydrodynamic disturbance device to transport the water in the relatively high temperature water layer upward to the preset outflow position, so as to use the generated directional surge to break the inverted temperature stratification structure of the water under the ice, thereby forming an isothermal mixing layer below the ice layer.

[0011] Preferably, the formula for calculating the real-time ice-water heat flux in step S3 is: In the formula, Fw is the ice-water heat flux, ki is the thermal conductivity of ice, T is the ice temperature, z is the vertical depth, ΔT / Δz is the ice temperature gradient, ρi is the ice density, Li is the latent heat of melting or freezing of ice, h is the ice thickness, t is time, and Δh / Δt is the rate of change of ice thickness.

[0012] Preferably, after calculating the real-time ice-water heat flux using the formula in step S3, the method further includes a cross-validation step: quantitatively estimating the heat loss rate of the water beneath the ice using the water body heat budget equation, and comparing the heat loss rate with the ice-water heat flux. The water body heat budget equation is as follows: In the formula, For lateral heat transfer in water, It is transmitted radiation. For heat transfer to the bottom mud, For ice-water heat flux, The density of water, For the specific heat of water, Because of the water depth, Because the ice is thick, The temperature of the water beneath the ice. Let t represent the water temperature and t represent the time.

[0013] Preferably, before calculating the real-time ice-water heat flux in step S3, the method further includes simultaneously acquiring real-time flow velocity data of multiple vertical layers adjacent to the bottom of the ice layer using an acoustic Doppler current profiler, and using a multivariate nonlinear regression algorithm to parameterize and fit the real-time flow velocity data, the subglacial water temperature, and the calculated real-time ice-water heat flux, establishing a multivariate fitting relationship between the ice-water heat flux and the subglacial water temperature and flow velocity, so as to quantitatively characterize the influence of hydrodynamic field changes on heat flux, and provide parameterization basis for numerical simulation and forecasting of ice condition evolution in the target area.

[0014] Preferably, adjusting the relative distance between the preset outflow position and the ice-water interface in step S4 specifically includes: when the preset ice layer formation and dissipation target is to accelerate ice melting, and the real-time ice-water heat flux is lower than the target heat flux, reducing the relative distance between the preset outflow position and the ice-water interface, or increasing the operating power driving the water transport, so as to enhance the turbulence intensity and coverage of the isothermal mixing layer below the ice layer, and after adjusting the relative distance or adjusting the operating power in step S4, cyclically returning to execute step S3 to form real-time state feedback control.

[0015] Preferably, after step S4, a dynamic compensation step is further included: acquiring meteorological monitoring data of the target area in real time, the meteorological monitoring data including at least ambient temperature and solar radiation intensity; if the decrease in ambient temperature or solar radiation intensity is determined to reach a preset meteorological compensation threshold based on the meteorological monitoring data, and the real-time ice thickness change data indicates that the ice melting rate has decreased to a preset melting rate threshold or turned negative, the heat loss caused by the meteorological change is compensated by changing the relative distance or adjusting the operating power; after the ice melting rate recovers to a value greater than the melting rate threshold, the process returns to the loop to execute steps S2 to S4 to form real-time state feedback control.

[0016] This invention also provides a reservoir ice layer formation and dissipation control system based on subglacial hydrodynamic disturbance, comprising: a hydrodynamic disturbance device for driving subglacial water to generate a disturbed water flow pointing towards the bottom of the ice layer; an outflow elevation adjustment module, cooperating with the hydrodynamic disturbance device, for adjusting the vertical distance between the outflow position of the disturbed water flow and the bottom of the ice layer; a monitoring module for acquiring ice layer and hydrological state parameters of the target area; and a control module, communicatively connected to the hydrodynamic disturbance device, the outflow elevation adjustment module, and the monitoring module, wherein the control module is configured to execute the above-described reservoir ice layer formation and dissipation control method based on subglacial hydrodynamic disturbance.

[0017] Compared with the prior art, the present invention has the following beneficial effects: This solution adopts a core architecture in the control stage that "calculates real-time ice-water heat flux based on the principle of ice-bottom heat balance, and adjusts the relative distance of the outflow position and / or operating power according to the deviation of the target heat flux." This enables the system to obtain accurate heat exchange physical quantities as the basis for action, changing the open-loop blind state of traditional anti-icing methods without quantitative feedback, and realizing precise and quantitative control of the ice generation and dissipation rate in the target area.

[0018] By driving water from a deep, relatively high-temperature water layer upwards and generating directional turbulent water flow, the system actively breaks the inverted temperature stratification structure of the water under the ice and forms an isothermal mixing layer. The system makes full use of the naturally stored thermal energy resources at the bottom of the reservoir and requires only extremely low equipment power consumption. For example, by driving a small submersible pump, it can leverage a huge amount of heat exchange at the ice-water interface, solving the problem of excessive energy consumption of traditional electric heating or heavy mechanical ice-breaking equipment. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0020] Figure 1 This is a flowchart of the reservoir ice layer generation and dissipation control method based on subglacial hydrodynamic disturbance of the present invention; Figure 2 This is a block diagram of the module logic of the reservoir ice layer generation and dissipation control system based on subglacial hydrodynamic disturbance of the present invention. Figure 3 This is a schematic diagram of the on-site physical layout of the control system and the three-dimensional temperature field monitoring array structure in an embodiment of the present invention; Figure 4 This is a graph showing the ice thickness variation process of each monitoring hole during the first time period under the first outflow elevation condition, according to an embodiment of the present invention. Figure 5 This is a graph showing the ice thickness variation process of each monitoring hole during the second time period under the first outflow elevation condition, according to an embodiment of the present invention. Figure 6 This is a graph showing the ice thickness variation process of each monitoring hole under the second outflow elevation condition according to an embodiment of the present invention. Figure 7 This is a graph showing the dynamic change of ice thickness at each monitoring well under the condition of third outflow elevation and sudden meteorological changes, according to an embodiment of the present invention. Figure 8 This is a time-series change of the sub-ice water temperature profile and the evolution of the isothermal mixing layer at a certain monitoring point under the first outflow elevation condition according to an embodiment of the present invention; wherein (a) is a line graph of real-time water temperature change at different depths from the bottom of the ice layer, and (b) is a thermal distribution map of the water temperature field in the depth-time dimension. Detailed Implementation

[0021] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0023] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0024] Furthermore, the use of terms such as "first" and "second" in this invention is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0025] Example 1 Combination Figure 2 and Figure 3 As shown in the figure, this embodiment discloses a reservoir ice layer formation and dissipation control system based on sub-ice hydrodynamic disturbance, which is deployed in a distributed manner on the reservoir ice surface and in the sub-ice water. The control system mainly includes a hydrodynamic disturbance device, an outflow elevation adjustment module, a monitoring module, a control module, and a power supply component.

[0026] Regarding the specific assembly logic and connection relationships: The support frame of the outflow elevation adjustment module is placed horizontally and supported on the outer ice layer at the opening of the natural ice surface of the reservoir. To adapt to the cold environment, the support frame is made of aluminum alloy profiles with anti-corrosion treatment or rigid fixed wooden piles, assembled into a cross structure by mortise and tenon joints or bolts. The base of the lifting mechanism is anchored to the top surface of the central intersection of the support frame by fastening bolts.

[0027] The submersible pump of the hydrodynamic disturbance device is suspended in the warm water layer below the ice surface, i.e., the relatively high-temperature water layer. The outlet of the submersible pump is rigidly connected to the bottom inlet of the guide pipe via a stainless steel clamp. The guide pipe extends vertically upward from underwater, with its top open end forming the outlet. The upper half of the outer wall of the guide pipe is mechanically connected to the traction component of the lifting mechanism via a clamping device. The submersible pump is preferably a brushless DC pump with a rated voltage of 12V and an operating power of 80W. The guide pipe is preferably made of low-temperature resistant high-density polyethylene (HDPE) pipe with a wall thickness of 3mm to 5mm to prevent low-temperature brittleness.

[0028] The monitoring module includes a three-dimensional temperature field monitoring array, an acoustic Doppler flow profiler (ADCP), and a thermal resistance ice thickness gauge. Figure 3(Represented by resistance wire) and a meteorological monitoring station. The three-dimensional temperature field monitoring array consists of multiple temperature chains suspended vertically under the ice. These temperature chains are respectively tied and fixed to nylon ropes at horizontal distances of 0m, 0.5m, 1.0m, and 2.0m from the center point of the guide pipe. The nylon ropes are equipped with counterweights, such as a weighted hammer. An acoustic Doppler current profiler is mounted upside down on the bottom surface of the ice layer via a rigid bracket, with its acoustic probe pointing downwards towards the water area where the submersible pump is located.

[0029] The data acquisition controller of the control module is built into the cavity of the sealed insulated box. The sealed insulated box is fixed to the side edge of the ice surface of the support frame by straps, and its cavity is filled with a polyurethane foam insulation layer with a thickness of not less than 50mm. The battery of the power supply component is also placed in the sealed insulated box and is electrically connected to the data acquisition controller, submersible pump and lifting mechanism through flexible wires. The photovoltaic panel on the ice surface is fixed to the ice surface at an angle by a bracket, and its output end is connected to the charging interface of the battery through an anti-freeze cable.

[0030] Expanding on the implementation of the higher-level concept of the "outflow elevation adjustment module": Specific Implementation A (Manual Low-Cost Type): The lifting mechanism is a manual crank winch, and the traction component is a rust-proof steel wire rope. The steel wire rope is wound by manually rotating the crank, which drives the guide pipe and submersible pump to lift vertically. It is suitable for small-scale or experimental control points.

[0031] Specific embodiment B (fully automatic precision type): The lifting mechanism includes a waterproof stepper motor and a gear and rack transmission pair. The rack is vertically fixed to the outside of the guide pipe. The stepper motor receives the electrical signal from the data acquisition controller to perform forward and reverse rotation, so as to realize the automatic and precise adjustment of the distance between the water outlet and the ice bottom.

[0032] Example 2 After the static structure is assembled as described above, the dynamic working principle and operation process of the control system are as follows: S1. Initial State Perception and 3D Archiving: The system is powered on and initialized. The data acquisition controller reads the initial hydrological state beneath the ice through the three-dimensional temperature field monitoring array. Specifically: 1. Acquiring initial ice condition data: The data acquisition controller reads the initial ice thickness data of the target area detected by the resistance temperature detector (RTD) before hydrodynamic disturbance through a wired communication link. For example, the initial floating ice cover thickness measured on site is 24cm. Simultaneously, it collects the initial temperature data of the ice layer inside each layer of the ice body, specifically the initial temperature data measured by temperature probes deployed at 10cm intervals along the vertical direction inside the ice layer, in order to establish the initial state benchmark of the ice body.

[0033] 2. Acquiring initial water temperature profile data of the subglacial water: The data acquisition controller initiates a three-dimensional temperature field monitoring array for spatial scanning. Specifically, using the center point of the preset outflow position defined by the outflow elevation adjustment module as a reference, multiple monitoring points are selected within the horizontal influence radius generated by the directional disturbance water flow. These points are located at horizontal distances of 0m, 0.5m, 1.0m, and 2.0m from the center point of the preset outflow position. Multiple temperature chains are suspended from these points. Using multiple high-precision thermistor temperature probes fixed at vertical distances of 20cm, 40cm, and 80cm from the bottom of the ice layer on each temperature chain, water temperature data at multiple depths within the target area are read synchronously and frequently. The control module performs matrix arrangement of these discrete multi-point and multi-layer water temperature data to construct the initial three-dimensional temperature field array of the subglacial water.

[0034] S2. Hydrodynamic Drive and Isothermal Mixing Layer Reconstruction: The data acquisition controller determines the depth of the relatively high-temperature water layer based on the initial water temperature profile data obtained in step S1. The relatively high-temperature water layer is a relative concept based on the physical characteristics of natural temperature inversion stratification under ice. Specifically, it refers to the warm water storage layer located in the lower part of the temperature inversion stratification structure, relative to the shallow cold water close to the bottom surface of the ice layer at near 0°C. In the specific logic control of the system, the data acquisition controller quantifies and limits it to a water temperature greater than or equal to a preset temperature threshold, preferably 2.0°C or higher in this embodiment, and a physical depth located at a preset depth, preferably 80cm or deeper below the ice bottom in this embodiment. Subsequently, the controller outputs a closed signal to drive the submersible pump of the hydrodynamic disturbance device. The submersible pump transports the warm water in the relatively high-temperature water layer upwards to a preset outflow position, generating a directional disturbed water flow pointing towards the ice-water interface within the target area. The ice-water interface refers to the physical critical boundary where the bottom of the solid floating ice sheet on the reservoir surface meets and contacts the liquid water below. Within the realm of thermodynamics, this interface is the heat exchange surface where the solid and liquid phases undergo phase transition, i.e., the melting of the ice bottom or the freezing of the water body. The heat transfer rate of this interface determines the dynamic process of the formation and dissipation of the ice layer at the bottom of the reservoir.

[0035] Under natural conditions without pumping disturbance, the water beneath the ice layer typically exhibits a "temperature inversion stratification" structure, with lower temperatures in the shallower layers and higher temperatures in the deeper layers. This structure hinders the transfer of heat from the deeper layers to the ice-water interface. The mechanical kinetic energy of the aforementioned directional flow actively breaks down and agitates the original temperature inversion stratification of the cold and hot water bodies, thereby forming an isothermal mixing layer beneath the ice layer. Specifically, this isothermal mixing layer refers to a dynamic mixed water layer of a certain thickness with essentially the same temperature at both the top and bottom, formed in the vertical space immediately adjacent to the bottom of the ice layer. This isothermal mixing layer directly serves as the high heat exchange boundary of the ice-water interface, providing a stable and direct basic heat source for accelerating ice melting.

[0036] S3. Multidimensional data cross-validation and heat flux calculation: During the disturbance, the data acquisition controller executes its core computational logic. First, it reads the ice thickness change rate Δh / Δt from the resistance temperature detector and the ice temperature gradient ΔT / Δz measured by the temperature probe, and substitutes these values ​​into the internally stored ice bottom heat balance equation: In the formula, For ice-water heat flux, Let be the thermal conductivity coefficient of ice, ΔT / Δz be the ice temperature gradient, and ρi be the density of ice. Let Δh / Δt be the latent heat of melting or freezing of ice, and let Δh / Δt be the rate of change of ice thickness.

[0037] Real-time ice-water heat flux was calculated using a forward method. .

[0038] To ensure precise and accurate control, the controller simultaneously captures velocity data from an acoustic Doppler current profiler across multiple shear layers ranging from 5 cm to 20 cm below the ice. In conjunction with meteorological and hydrological data such as transmitted radiation and bottom heat transfer, the water body heat budget equation is used: In the formula, For lateral heat transfer in water, It is transmitted radiation. For heat transfer to the bottom mud, For ice-water heat flux, The density of water, For the specific heat of water, Because of the water depth, Because the ice is thick, The temperature of the water beneath the ice. Let t be the water temperature and t be the time, where t represents the lateral heat transfer of the water body. The calculations were performed based on classical fluid heat transfer formulas, using horizontal flow velocities measured by the acoustic Doppler velocity profiler. The results were obtained by combining the horizontal temperature gradient between multiple temperature chains located at different horizontal distances from the outlet.

[0039] Estimate the rate of heat loss, and compare it with the previously calculated rate. Perform a comparison. If the error is within the preset tolerance range, a judgment is made. If valid, the abnormal data is input as the current real-time ice-water heat flux into the subsequent step S4 for deviation calculation; otherwise, the abnormal data is discarded and a remeasurement is triggered.

[0040] In addition, before calculating the real-time ice-water heat flux, a parameterized modeling step is included to quantitatively characterize the impact of hydrodynamic field changes on the heat flux. The specific construction process includes the following steps: First, real-time flow velocity data of multiple vertical layers adjacent to the bottom of the ice layer were acquired simultaneously using an acoustic Doppler flow profiler. Specifically, flow velocity values ​​were collected at distances of 5cm, 10cm, 15cm, and 20cm from the bottom of the ice layer. Secondly, the data acquisition controller performs spatial averaging on the real-time flow velocity data from multiple vertical layers to eliminate instantaneous fluctuations in local turbulence and obtain representative characteristic flow velocities as sub-ice flow velocities. Simultaneously, real-time probe data adjacent to the ice bottom in the three-dimensional temperature field array is extracted as the current subglacial water temperature. ; Subsequently, at the aforementioned sub-ice flow rate and real-time ice water temperature The current real-time ice-water heat flux, calculated based on the aforementioned ice-bottom heat budget balance principle, is used as the independent variable. As the dependent variable, a multivariate nonlinear regression analysis algorithm, such as least squares or multivariate polynomial regression, is run to perform parameterized solutions, thereby establishing the real-time ice-water heat flux. With the temperature of water under ice and sub-ice flow velocity The multivariate fitting relationship between them is represented by the conceptual framework as follows: ; Finally, the empirical formula coefficients determined by the fitting are solidified into the data acquisition controller of the control module, enabling the system to run the parameterization scheme online to quantitatively characterize the impact of hydrodynamic field changes on the ice-water heat flux, and to provide parameterization basis for numerical simulation and forecasting of ice condition evolution in the target area.

[0041] S4. Deviation Correction and Feedback Control: In step S4, the accelerated melting of ice refers to an active control target state of the system. Specifically, during the wintering period of the reservoir or the period of high incidence of ice damage, a target melting rate is artificially set by the control module so that the target heat flux required by the control system is greater than the inherent heat flux of the environment under the natural temperature inversion stratification state. This is achieved by driving the hydrodynamic disturbance device to input kinetic energy into the water body under the ice, thereby increasing the heat exchange rate of the ice-water interface and making the melting rate of the bottom of the ice layer significantly exceed its natural melting rate or change from the ice growth state to the rapid melting state.

[0042] In the specific implementation process, when the preset ice layer formation and dissipation target is the accelerated ice melting, and the system calculates the real-time ice-water heat flux in step S3... When the heat flux is lower than the target, it indicates that the current turbulent mixing intensity and boundary layer heat transport cannot meet the preset melting rate requirement. Based on this deviation, the control module outputs an adjustment command to drive the lifting mechanism to reduce the relative distance between the outflow position and the ice-water interface, and / or increase the operating power of the submersible pump. By shortening the jet distance or increasing the kinetic energy of the inrush flow, the turbulence intensity and coverage of the isothermal mixing layer below the ice layer are enhanced, so that the real-time ice-water heat flux at the interface is rapidly increased to the expected level, thereby achieving the technical effect of accelerating ice melting.

[0043] After adjusting the output, the system automatically returns to step S3 in a loop, forming a dynamic correction loop through high-frequency status data feedback.

[0044] During the continuous operation of the aforementioned closed-loop feedback control or meteorological dynamic compensation, the data acquisition controller of the control module executes the termination determination procedure of the control system based on the real-time acquired status parameters and preset safety boundaries, so as to safely exit the current control mode or shut down the system in a timely manner. The specific termination conditions cover the following three operating path: 1. Termination upon achievement of target conditions: When the system's preset melting target is to accelerate ice melting, and the real-time ice thickness reported by the thermal resistance ice thickness gauge decreases to zero, or reaches the preset safe non-icing radius of the gate or water diversion structure, the control module determines that the ice hazard threat within the protected area has been completely eliminated; or, when the preset target is to delay ice melting or promote icing, and the real-time ice thickness increases and stably reaches the preset target thickness threshold required for winter traffic load and structure counterweight, the control module determines that the target conditions have been achieved, and outputs a control termination command accordingly, disconnects the submersible pump's power supply, and drives the lifting mechanism to lift and reset the outlet and submersible pump to the highest safe elevation position. The system then enters standby monitoring mode or exits the winter control program.

[0045] 2. Heat source depletion safety protection termination: During system regulation, if the initial water temperature profile data or real-time temperature display of the mixing layer fed back by the three-dimensional temperature field monitoring array shows that the water temperature at all depths under the ice is consistently below the set threshold, for example, consistently below 0.5°C, it indicates that the heat content of the naturally stored inverted warm water layer at the bottom of the reservoir can no longer meet the regulation requirements and can no longer provide effective heat flux to the ice-water interface. At this time, in order to avoid the submersible pump running dry in the absence of a heat source, which would cause energy waste or even secondary freezing of the water flow at the local outlet, the control module triggers a safety protection interruption, actively terminates the adjustment of the relative distance of the outflow and the operating power, shuts down the submersible pump, and sends a heat source depletion warning signal to the remote data acquisition terminal.

[0046] 3. Seasonal environmental changes naturally cease, and the control system continues to operate during the wintering period. When the daily average meteorological data and ambient air temperature reported by the meteorological monitoring station are higher than the set temperature for several consecutive days, such as five consecutive days with a daily average temperature above 0°C, or when real-time ice thickness change data indicates that the floating ice cover in the reservoir area has entered the stage of large-scale natural thawing and complete melting during the spring ice jam season, the control module determines that the reservoir area has left the winter ice damage cycle and the natural environment has the ability to melt autonomously. The system then automatically terminates the closed-loop feedback control program, cuts off the power supply link of all hardware modules, and completes the ice prevention and control task for the entire wintering cycle.

[0047] Example 3 The weather in the cold plateau region is complex and changeable during the winter. In order to ensure that the ice melting link is not interrupted under extreme conditions, this embodiment further introduces a meteorological change compensation response, namely a dynamic compensation step, after step S4.

[0048] During normal system operation, the data acquisition controller acquires digital signals from the weather station in real time. When encountering sudden weather events such as snowfall, heavy overcast skies, or cold waves, causing a drop in ambient temperature or solar radiation intensity to reach the preset meteorological compensation threshold, and when the data acquisition controller simultaneously monitors real-time ice thickness change data from the resistance temperature detector (RTD) indicating that the ice melting rate has dropped to the preset melting rate threshold or turned negative, the system determines that the conventional hydrodynamic field can no longer resist the severe heat dissipation from the external environment.

[0049] At this point, the system automatically triggers the underlying interrupt priority: bypassing the conventional heat flux deviation calculation closed loop in step S4, and outputting a super-level compensation signal for full-load operation. Specifically, the controller increases the submersible pump's operating power from the normal cruising state, such as 60% of rated power, to 100% full-load operation, while simultaneously driving the lifting mechanism to raise the preset outflow position to within a very small safe distance from the ice-water interface, i.e., maximally shortening the relative distance. This dynamic compensation mechanism maximizes the extraction and delivery of basic heat from the relatively high-temperature water layer under the ice by enhancing physical and mechanical disturbances, offsetting the heat loss caused by drastic external weather changes, thereby reconstructing and maintaining an isothermal mixing layer that meets compensation requirements in a very short time, ensuring that the ice layer does not freeze irreversibly. During the execution of dynamic compensation, the system continuously monitors real-time ice thickness change data. Once the indicated ice melting rate recovers to a level greater than the melting rate threshold, the controller automatically releases the compensation signal and returns to the loop to execute steps S2 to S4 to restore the conventional heat flux deviation calculation and hydrodynamic closed-loop control.

[0050] It should be noted that the meteorological compensation threshold described in this embodiment is not a fixed absolute constant. Those skilled in the art can adaptively calibrate it in practical engineering applications based on historical wintering meteorological statistics of the target reservoir, the basic heat capacity of the submersible water, and the maximum compensation power of the submersible pump. For example, for solar radiation intensity, the compensation threshold can be set to correspond to a critical attenuation of 30% of the average transmitted radiation falling below the average on a severely cloudy day or under heavy snowfall; for ambient temperature, it can be set to the critical temperature difference at which a sharp drop in temperature occurs within a short period, such as within one hour. This dynamic calibration rule based on engineering practice ensures that the dynamic compensation mechanism is not blindly triggered during minor meteorological fluctuations, and that it can achieve a precise and decisive escalation response when encountering extreme heat dissipation crises.

[0051] Compared with the prior art, the preferred embodiments have the following advantages. This system is further equipped with a dynamic compensation mechanism that includes meteorological monitoring and deviation feedback. Therefore, when severe weather conditions such as snowfall, cloudy days, or a sharp drop in temperature at night occur in high-altitude and cold regions, which hinder the melting of ice, the system can adaptively reduce the relative distance or increase the disturbance power to offset the heat loss caused by the harsh environment, thereby ensuring the system stability and continuous ice melting efficiency under extremely cold conditions.

[0052] Because the control system automatically cycles back to the execution status monitoring and heat flux calculation after the control action is executed, the entire control system forms a tight closed-loop feedback link. It can achieve status correction without continuous manual intervention, which greatly reduces the risk and maintenance cost of manual inspection at the reservoir site in winter. The closed-loop response also solves the technical problem of low control accuracy in existing technologies.

[0053] Experimental verification and effect analysis To verify the control effect of the method and system described in this invention under different hydrodynamic fields and meteorological conditions, a multi-condition field test was conducted at the Pangduo Reservoir in Tibet. It should be noted beforehand that, to visually demonstrate the ice condition evolution under various conditions, this embodiment uses a diagram... Figures 4 to 7 The curve showing the dynamic change process of ice thickness is shown. Figures 4 to 7 In the figure, the horizontal axis represents the horizontal distance of each monitoring hole from the central hole, and the vertical axis represents the ice thickness value. The data lines in the figure represent the spatial distribution of ice cover thickness at different measurement times.

[0054] 1. Comparative Verification of Elevation Adjustment Control The system was tested under the following operating conditions: first outflow elevation, 100cm from the ice bottom; and second outflow elevation, 200cm from the ice bottom.

[0055] As shown in Table 1, Table 2 and Figure 4 , Figure 5As shown, when the outflow position is 100cm from the ice bottom, for ease of recording, the center point of the preset outflow position is designated as the central hole in this embodiment. The closer to the central hole, the greater the ice thickness melting, with the ice thickness change at the central hole being approximately 10.6cm. During this operating condition, the peak melting rate at the central hole reaches 0.077 cm / min, and the calculated ice-water heat flux jumps to approximately 2290 W / m². This indicates that the system can leverage the ice using only about 80W of operating power. Interfacial heat exchange at the W / m² level enables highly energy-efficient targeted ice melting.

[0056] For comparative verification, see Table 3 and Figure 6 As shown, when the system lowers the outflow position to 200 cm from the ice bottom, although the temperature of the deep-extracted mixed layer water increases, reaching 3.5℃ at a depth of 80 cm, the local hydrodynamic turbulence intensity weakens due to the distance of the outflow position from the ice bottom, resulting in a decrease in the melting rate of the central orifice to 0.011 cm / min. This set of comparative experiments strongly confirms the scientific nature of step S4 of the method of the present invention: by changing the vertical elevation of the outflow position, the intensity of the local hydrodynamic field can be effectively changed, thereby precisely controlling the ice-water heat flux and the ice melting rate.

[0057] Table 1: Rate of change of ice thickness at each measuring point during the first time period under the 100cm working condition (cm / min) Table 2: Rate of change of ice thickness at various measuring points during the second time period under the 100cm working condition (cm / min) This indicates that the data was not measured. Table 3: Rate of change of ice thickness at various measuring points under the 200cm working condition (cm / min) 2. Verification of the dynamic meteorological compensation mechanism As shown in Table 4 and Figure 7 As shown, the system encountered snowfall while operating at the third outflow elevation, 150 cm below the ice bottom, followed by overcast skies and nighttime. The snowfall and overcast weather directly suppressed the source of transmitted radiative heat from the water beneath the ice, leading to a significant decrease in the melting rate at various points, and even refreezing at night. The rate at the central orifice dropped to -0.0014 cm / min after 18:50. This operating condition clearly indicates the severe inhibitory effect of adverse weather conditions on anti-icing effectiveness, thus confirming the necessity of introducing a dynamic meteorological compensation step in this invention: based on this type of heat attenuation feedback, the system can promptly trigger actions to further reduce the elevation or increase power to offset the precipitous drop in heat radiation caused by drastic external weather changes, ensuring uninterrupted ice melting under extreme conditions.

[0058] Table 4: Rate of change of ice thickness at various measuring points (cm / min) under the 150cm operating condition (including sudden meteorological changes) 3. Reconstruction Verification of the Under-Ice Isothermal Hybrid Layer To visually verify the actual effect of the hydrodynamic disturbance of this invention on the three-dimensional temperature field under ice, combined with Figure 8 As shown in the figure, this diagram illustrates the temporal variation of the subglacial water temperature profile and the evolution of the isothermal mixing layer at a monitoring point, such as 50 cm to the right of the central orifice, under the first outflow elevation (100 cm) condition. Among these, Figure 8 The upper part (a) shows the real-time water temperature variation lines at 20cm, 40cm and 80cm from the ice bottom; the lower part (b) shows the thermodynamic distribution of the water temperature field in the depth-time dimension.

[0059] Combination Figure 8 As can be seen, in the natural state before the experimental disturbance, the water under the ice exhibits a significant "temperature inversion stratification" structure, meaning that the water temperature is lower at a shallow depth of 20cm and higher at a deep depth of 80cm, with the thermogram showing obvious lateral stratification color differences. When the system is triggered and the submersible pump starts, as shown by the dotted line in the experimental period, the temperature lines at different depths quickly converge and overlap, and the temperature gradient in the vertical direction of the thermogram decreases sharply. This measured monitoring data directly confirms that the directional disturbance water flow of the present invention can successfully break the natural temperature inversion layer, transport the relatively high-temperature water stored at the bottom upwards, and construct an "isothermal mixing layer" with a more uniform temperature adjacent to the bottom of the ice layer, thus providing experimental data support for the underlying physical mechanism of step S2 mentioned above.

[0060] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A method for regulating the formation and dissipation of reservoir ice layers based on subglacial hydrodynamic disturbance, characterized in that, Includes the following steps: S1, Obtain the initial state parameters of the target area, wherein the initial state parameters include at least the initial ice condition data and the initial water temperature profile data of the subglacial water body; S2, determine a relatively high-temperature water layer based on the initial water temperature profile data, and drive the water in the relatively high-temperature water layer to be transported to a preset outflow position to generate a directional disturbed water flow pointing towards the ice-water interface in the target area; S3, acquire real-time ice thickness change data and real-time ice layer temperature data of the target area, calculate real-time ice-water heat flux based on the principle of ice bottom heat balance, and determine the corresponding target heat flux according to the preset ice layer generation and dissipation target. S4. Based on the deviation between the target heat flux and the real-time ice-water heat flux, adjust the relative distance between the preset outflow position and the ice-water interface, and / or adjust the operating power driving the water transport, so as to control the heat exchange rate of the ice-water interface.

2. The reservoir ice layer formation and dissipation control method based on subglacial hydrodynamic disturbance as described in claim 1, characterized in that, The initial ice condition data in step S1 includes the initial ice thickness of the target area before the hydrodynamic disturbance is implemented and the initial temperature inside the ice layer.

3. The reservoir ice layer formation and dissipation control method based on subglacial hydrodynamic disturbance as described in claim 1, characterized in that, The specific steps of obtaining the initial water temperature profile data in step S1 include: using the center point of the preset outflow location as a reference, deploying temperature chains at multiple monitoring points within the horizontal influence radius generated by the directional disturbance water flow, and using multiple temperature probes fixedly deployed on each temperature chain to simultaneously acquire water temperature data at multiple depth layers within the target area, so as to construct a three-dimensional temperature field array of the subglacial water body.

4. The reservoir ice layer formation and dissipation control method based on subglacial hydrodynamic disturbance as described in claim 1, characterized in that, The step S2 of driving the water in the relatively high temperature water layer to the preset outflow position specifically includes: using a hydrodynamic disturbance device to transport the water in the relatively high temperature water layer upward to the preset outflow position, so as to use the generated directional flow to break the inverted temperature stratification structure of the water under the ice, thereby forming an isothermal mixing layer below the ice layer.

5. The reservoir ice layer formation and dissipation control method based on subglacial hydrodynamic disturbance as described in claim 1, characterized in that, The formula for calculating the real-time ice-water heat flux in step S3 is as follows: In the formula, For ice-water heat flux, Let T be the thermal conductivity coefficient of ice, T be the ice temperature, z be the vertical depth, and ΔT / Δz be the ice temperature gradient. The density of ice, Let be the latent heat of melting or freezing of ice, h be the ice thickness, t be time, and Δh / Δt be the rate of change of ice thickness.

6. The reservoir ice layer formation and dissipation control method based on subglacial hydrodynamic disturbance according to claim 5, characterized in that, After calculating the real-time ice-water heat flux using the formula in step S3, the method further includes a cross-validation step: quantitatively estimating the heat loss rate of the water beneath the ice using the water body heat budget equation, and comparing the heat loss rate with the ice-water heat flux. The water body heat budget equation is as follows: In the formula, For lateral heat transfer in water, It is transmitted radiation. For heat transfer to the bottom mud, For ice-water heat flux, The density of water, For the specific heat of water, Because of the water depth, Because the ice is thick, The temperature of the water beneath the ice. Let t represent the water temperature and t represent the time.

7. The reservoir ice layer formation and dissipation control method based on subglacial hydrodynamic disturbance as described in claim 1, characterized in that, Before calculating the real-time ice-water heat flux in step S3, the method further includes using an acoustic Doppler current profiler to simultaneously acquire real-time flow velocity data of multiple vertical layers adjacent to the bottom of the ice layer, and using a multivariate nonlinear regression algorithm to parametrically fit the real-time flow velocity data, the subglacial water temperature, and the calculated real-time ice-water heat flux, thereby establishing a multivariate fitting relationship between the ice-water heat flux and the subglacial water temperature and flow velocity, in order to quantitatively characterize the influence of changes in the hydrodynamic field on the ice-water heat flux.

8. The reservoir ice layer formation and dissipation control method based on subglacial hydrodynamic disturbance as described in claim 1, characterized in that, The adjustment of the relative distance between the preset outflow position and the ice-water interface in step S4 specifically includes: when the preset ice layer formation and dissipation target is to accelerate ice melting, and the real-time ice-water heat flux is lower than the target heat flux, reducing the relative distance between the preset outflow position and the ice-water interface, or increasing the operating power driving the water body to transport water, so as to enhance the turbulence intensity and coverage of the isothermal mixing layer below the ice layer, and after adjusting the relative distance or adjusting the operating power in step S4, cyclically returning to execute step S3 to form real-time state feedback control.

9. The reservoir ice layer formation and dissipation control method based on subglacial hydrodynamic disturbance as described in claim 1, characterized in that, Following step S4, a dynamic compensation step is also included: real-time acquisition of meteorological monitoring data of the target area, the meteorological monitoring data including at least ambient temperature and solar radiation intensity; if the decrease in ambient temperature or solar radiation intensity is determined to reach a preset meteorological compensation threshold based on the meteorological monitoring data, and real-time ice thickness change data indicates that the ice melting rate has decreased to a preset melting rate threshold or turned negative, the heat loss caused by meteorological changes is compensated by changing the relative distance or adjusting the operating power; after the ice melting rate recovers to a level greater than the melting rate threshold, the process returns to the loop to execute steps S2 to S4 to form real-time state feedback control.

10. A reservoir ice layer formation and dissipation control system based on subglacial hydrodynamic disturbance, characterized in that, include: A hydrodynamic disturbance device is used to drive the water body under the ice to generate a disturbed water flow pointing towards the bottom of the ice layer; The outflow elevation adjustment module, in conjunction with the hydrodynamic disturbance device, is used to adjust the vertical distance between the outflow position of the disturbed water flow and the bottom of the ice layer; the monitoring module is used to acquire ice layer and hydrological state parameters of the target area; the control module is communicatively connected to the hydrodynamic disturbance device, the outflow elevation adjustment module, and the monitoring module, respectively, and the control module is configured to execute the reservoir ice layer generation and dissipation control method based on sub-ice hydrodynamic disturbance as described in any one of claims 1 to 9.

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