Environment-friendly desilting method and system for high-pressure gas-water linkage negative-pressure mud suction

Abstract

The invention relates to the technical field of water area desilting, and discloses a green desilting method and system for high-pressure gas-water linkage negative-pressure mud suction, and the method comprises the following steps: S1, collecting pressure data of a muddy water medium in an area through a density sensing assembly and a speed sensing assembly; s2, a low-pressure area is judged according to the collected pressure data; s3, a high-pressure water pump is started, and high-pressure water flow is sprayed to the periphery of the suction domain through a high-pressure water nozzle; s4, a high-pressure air compressor is started, and high-pressure gas is sprayed into the muddy water medium through a high-pressure air nozzle; s5, in the water flow and gas injection process, the water flow injection direction or injection amount is adjusted according to the preset velocity field constraint; and S6, according to the density deviation value, the water flow variable quantity and the pressure variable quantity, constructing a comprehensive control quantity. The gas injection amount and the water flow injection amount are adjusted in a linkage mode, so that the local density change and the velocity field change are matched with the negative pressure suction requirement at the same time, and the effect of synchronously controlling sediment suspension and the transportation path is achieved.

Description

Technical Field

[0001] This invention relates to the field of water dredging technology, specifically to a green dredging method and system that uses high-pressure air-water linkage negative pressure suction. Background Technology

[0002] With the increasing demand for water environment management and ecological restoration, the dredging of silt in rivers, lakes, and reservoirs is gradually moving towards eco-friendly and low-disturbance methods. "Green dredging," a governance concept that has emerged in recent years, emphasizes minimizing disturbance to aquatic ecosystems, water transparency, benthic organisms, and shoreline environments while removing silt. To achieve a more environmentally friendly effect on water bodies, dredging equipment and methods are gradually shifting from traditional heavy-duty excavation to more flexible and controllable dredging modes such as hydrodynamic disturbance, gas loosening, and negative pressure transport.

[0003] In related technologies, gas disturbance and water jet are often controlled independently, and negative pressure suction lacks real-time correlation with density changes and velocity field changes, resulting in unstable sediment suspension height, easy interruption of transport path due to local settlement, and difficulty in maintaining continuity of the overall transport process. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a green dredging method and system for high-pressure air-water linkage negative pressure sludge suction, which solves the problems of unstable sludge suspension height, easy interruption of the transport path due to local settlement, and difficulty in maintaining continuity of the overall transport process.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A green sludge removal method using high-pressure air-water linkage negative pressure suction includes the following steps: S1. The sludge removal head, which integrates a high-pressure water nozzle, a high-pressure air nozzle, and a negative pressure sludge suction port, is lowered to the target sludge layer area, and the pressure data of the mud-water medium in the area is collected by the density sensing component and the velocity sensing component. S2. Based on the collected pressure data, determine the low-pressure area, take the low-pressure area as the suction area, and monitor the boundary of the suction area according to the pressure distribution to control the suction force. S3. Start the high-pressure water pump and spray high-pressure water jets into the surrounding area of ​​the suction zone through the high-pressure water nozzles to cut and disturb the silt, and adjust the water jet volume according to the density field distribution. S4. Start the high-pressure air compressor and inject high-pressure gas into the mud-water medium through the high-pressure air nozzle. Set the gas injection amount according to the density field change to adjust the mud and sand distribution and density change. S5. During the process of water flow and gas jetting, the velocity field distribution is analyzed, and the water jetting direction or jetting amount is adjusted according to the preset velocity field constraints to maintain the specified flow structure of the velocity field. S6. Construct a comprehensive control quantity based on the density deviation, water flow change, and pressure change, and adjust the gas injection module, water flow injection module, and negative pressure suction module in a coordinated manner based on the comprehensive control quantity to ensure that the operating parameters of the modules are coordinated.

[0006] As a further description of the above technical solution: the density sensing component in S1 includes a conductivity sensor, and the velocity sensing component includes a flow velocity measurement sensor, which are used to synchronously collect the density and velocity of the mud-water medium at multiple spatial locations. The pressure data includes density distribution and velocity distribution. S1 also includes the following steps: The density of the mud-water medium at various locations within a spatial range is obtained using a conductivity sensor. The three-dimensional velocity field distribution within the spatial range is obtained using a flow velocity measurement sensor.

[0007] Through the above technical solution, the density sensing component includes a conductivity sensor, which acquires the density of the mud-water medium at various locations within a spatial range, and the velocity sensing component includes a flow velocity measurement sensor, which acquires the three-dimensional velocity field distribution within the spatial range.

[0008] As a further description of the above technical solution: S2 includes the following steps: Set a pressure threshold and define the region where the pressure is below the threshold as the suction zone; The change in the boundary pressure gradient of the suction domain is calculated to determine whether the topology of the suction domain has changed. When a topological change trend occurs in the suction domain, a suction domain adjustment operation is triggered. The low-pressure region is determined based on a preset pressure threshold. A continuous region with pressure below the threshold is defined as a suction region, and the boundary of the suction region is continuously monitored based on the change in the boundary pressure gradient of the region.

[0009] Through the above technical solution, a pressure threshold is set and the area with pressure below the threshold is determined as the suction domain. The change in the boundary pressure gradient of the suction domain is calculated to determine whether the topology of the suction domain has changed. When the suction domain shows a trend of topological change, the suction domain adjustment operation is triggered. The determination of the low-pressure area is based on the preset pressure threshold. The continuous area with pressure below the threshold is defined as the suction domain, and the boundary of the suction domain is continuously monitored according to the change in the boundary pressure gradient of the area.

[0010] As a further description of the above technical solution: S3 includes the following steps: The density diffusion amount is set based on the spatial variation of the density distribution; The sediment accumulation inhibition amount is set based on local sediment content changes; The density source quantity is set based on the gas injection behavior and the source quantity is dynamically adjusted. Based on the deviation distribution between the density field and the target density field, the deviation values ​​at each location are weighted and summarized, and the summarized results are used as the basis for adjusting the gas injection amount.

[0011] The above technical solution enables a controllable relationship between density changes and gas injection, water flow disturbance, and sediment distribution, thereby allowing subsequent velocity field settings and negative pressure suction adjustments to be set based on a relatively stable density distribution.

[0012] As a further description of the above technical solution: S4 includes the following steps: Set the constraint that the curl of the velocity field is zero; The direction or amount of water jet is adjusted based on the velocity field divergence deviation to ensure that the velocity field meets the curl constraint.

[0013] The above technical solution can keep the flow direction and flow structure within the working area within the preset velocity field constraint range, thereby allowing the water flow disturbance, mud and water transport and negative pressure suction processes to be controlled based on the interrelated velocity distribution.

[0014] As a further description of the above technical solution: S5 includes the following steps: Construct a set of delay parameters that includes density deviation and density gradient. Feedforward compensation is performed on the negative pressure suction force based on the input quantity corresponding to the set of delay parameters; The constraint on the velocity field is achieved by setting the velocity field curl to zero, and the direction of water jet is corrected based on this control condition.

[0015] The above technical solution keeps the input of negative pressure suction and the response of the mud-water medium to changes over time within a controllable range, thereby establishing a correspondence between suction, water flow distribution and density regulation based on delay characteristics.

[0016] As a further description of the above technical solution: S6 includes the following steps: Set a comprehensive control quantity that includes density deviation, water flow change, and negative pressure suction change; The gas injection volume, water injection volume, and negative pressure suction are adjusted in a correlated manner based on the aforementioned comprehensive control parameters. The comprehensive control quantity consists of density deviation, water flow change, and pressure change. The comprehensive control quantity is used to uniformly set the three types of control quantities: gas injection, water flow injection, and negative pressure suction.

[0017] The above technical solution enables gas injection, water flow disturbance and negative pressure suction to form a corresponding relationship under the same control framework, so that the adjustment logic of each control quantity remains consistent during the time and space changes, thereby enabling the multi-physics parameters in the dredging process to be in a state of coordinated control.

[0018] As a further description of the above technical solution: S3 further includes: during the joint control process, constraining the structure of the suction domain according to the correspondence between the density field, velocity field and pressure field, so as to keep the suction domain continuous; The high-pressure water jet volume is set based on the spatial variation of sediment distribution in the density field to ensure that the jet volume corresponds to the sediment distribution.

[0019] The above technical solutions ensure the continuity of the suction domain boundary while enabling water jetting and gas injection to match the distribution of the mud-water medium in real time, thereby improving the control accuracy and spatial coordination during operation.

[0020] As a further description of the above technical solution: S4 further includes: the adjustment includes setting the gas injection position and the gas injection duration; The amount of gas injected is adjusted based on local changes in the density field; The adjustment of the water jet volume is based on the change in the divergence of the velocity field; The change is used to correct the flow rate of the water jet module.

[0021] The above technical solution can maintain a corresponding relationship between gas injection, water jetting and local changes in velocity and density fields, and set the values ​​of velocity distribution curl constraint, water flow disturbance and density adjustment under the same control logic, so that the relevant control behaviors maintain a relatively consistent response relationship during spatial and temporal changes.

[0022] As a further description of the above technical solution: a high-pressure air-water linkage negative pressure sludge suction green dredging system, the system comprising: Density sensing module, used to acquire the density distribution of mud-water medium; The velocity sensing module is used to acquire the fluid velocity distribution; The negative pressure suction module is used to provide negative pressure suction and form a suction area; Gas injection module, used to inject gas into the target area; Water jet module, used to spray water jets onto target areas; The control module is used to control the gas injection module, water injection module, and negative pressure suction module based on density data, velocity data, and pressure data. Through the above technical solution, a corresponding control relationship can be formed between density sensing, velocity sensing, negative pressure suction, gas injection, and water injection. This allows multi-source data to be comprehensively processed under the same control framework, enabling the formation of the suction domain, the gas disturbance effect, and the water injection process to be controlled based on the spatial distribution of the mud-water medium. This ensures that the density, velocity, and pressure changes involved in the dredging process are in a coordinated adjustment state.

[0023] As a further description of the above technical solution, the system further includes: A surface work platform is used to carry all equipment and personnel. The dredging unit includes a dredging head and a connecting hose; The sludge removal head is an integrated design, which integrates at least one high-pressure water nozzle, at least one high-pressure air nozzle, and a suction port that surrounds or is located in the center. The power and control unit includes a high-pressure water pump, a high-pressure air compressor, a negative pressure suction system, and a centralized control cabinet for regulating the pressure and flow rate of water and air and the suction force of the suction system. The mud-water separation and treatment unit is used to receive the pumped mud, perform solid-liquid separation, and use it for water recycling and environmentally friendly soil disposal.

[0024] This invention provides a green sludge removal method and system using high-pressure air-water linkage negative pressure sludge suction. It has the following beneficial effects: 1. In this invention, by adjusting the gas injection volume and water jet volume in a coordinated manner, the local density change and velocity field change are simultaneously matched with the negative pressure suction demand, which achieves the effect of synchronously controlling the suspension and transport path of sediment. Compared with related technologies that rely on a single water flow or a single negative pressure drive, this invention solves the problems of rapid sediment settling and unstable transport chain.

[0025] 2. In this invention, by combining density field sensing and velocity field sensing, real-time mapping of the state of mud-water medium is achieved, which has the effect of constructing a dynamic suction domain. Compared with the method of judging the suction zone by single-point pressure in related technologies, this invention solves the problems of easy drift of the suction domain and inaccurate boundary locking.

[0026] 3. In this invention, the direction and amount of water jet are corrected by constraining the velocity field divergence and curl, which ensures the continuity of the flow structure. Compared with the control strategies in related technologies that cannot maintain the velocity field structure, this invention solves the technical defects of water flow turbulence and unstable mud-water transport path.

[0027] 4. In this invention, by constructing a comprehensive control quantity composed of density deviation, water flow change and pressure change, and jointly adjusting gas injection, water flow injection and negative pressure suction, the effect of multi-physical quantity coordinated control is achieved. Compared with the control system in related technologies where each module operates independently and responds asynchronously, this invention solves the problems of adjustment lag, control quantity conflict and low overall efficiency. Attached Figure Description

[0028] Figure 1 This is a flowchart of a green dredging method using high-pressure air-water linkage negative pressure sludge suction according to the present invention; Figure 2 This is a schematic diagram of the system architecture of a green dredging system with high-pressure air-water linkage negative pressure sludge suction according to the present invention. Detailed Implementation

[0029] The technical solution of the present invention will now be clearly and completely described 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 them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] To better understand the above technical solutions, the technical solutions of the present invention will be clearly and completely described below in conjunction with embodiments.

[0031] Please see the appendix Figure 1 This invention provides a green sludge removal method using high-pressure air-water linkage negative pressure sludge suction, comprising the following steps: S1. The sludge removal head, which integrates a high-pressure water nozzle, a high-pressure air nozzle, and a negative pressure sludge suction port, is lowered to the target sludge layer area, and the pressure data of the mud-water medium in the area is collected by the density sensing component and the velocity sensing component. The density sensing component in S1 includes a conductivity sensor, and the velocity sensing component includes a flow velocity measurement sensor, which are used to synchronously collect the density and velocity of the mud-water medium at multiple spatial locations. The pressure data includes density distribution and velocity distribution. S1 also includes the following steps: The density of the mud-water medium at various locations within a spatial range is obtained using a conductivity sensor. The three-dimensional velocity field distribution within a spatial range is obtained through a flow velocity measurement sensor.

[0032] Specifically, several conductivity sensors are deployed within the dredging area to acquire the density distribution of the sludge-water medium in real time. These sensors are typically mounted on the outer frame or suction port of the dredging equipment, ensuring coverage of every important location within the dredging area. Each sensor reflects the conductivity of the sludge-water medium by measuring a conductivity value (σ), which has a linear relationship with the density of the sludge-water medium. The conductivity value is converted to a density value using the following formula: ρ=ρ0+k·(σ-σ0); Where: ρ is the calculated density of the mud-water medium; ρ0 is the reference water density; σ is the conductivity measured by the sensor in real time; σ0 is the corresponding reference conductivity value; k is the proportionality coefficient between the change in conductivity and the change in density; To prevent signal fluctuations caused by localized changes in sediment concentration, a smoothing process can be used to preprocess the data. The smoothing formula is as follows: Where, σ i This represents the conductivity value at the current sampling point. This is the smoothed conductivity value; Flow velocity measurement sensors are used to obtain the three-dimensional velocity field distribution of the dredging area. The flow velocity sensor can be an acoustic Doppler current meter, an impeller sensor or an electromagnetic current meter, etc. The specific selection can be based on the actual environment and needs. The velocity measured by the flow velocity sensor is local flow velocity data. The three-dimensional velocity field of the entire area can be reconstructed by interpolation method. The three components of the velocity field are u, v and w. Where: u is the velocity component in the x-direction; v is the velocity component in the y-direction; and w is the velocity component in the z-direction. Velocity field interpolation can be performed using the weighted inverse distance interpolation method, with the specific expression as follows: u(x,y,z)=∑ j w j ·u j ; v(x,y,z)=∑ j w j ·v j ; w(x,y,z)=∑ j w j ·w j ; Where j represents the surrounding sampling points, w j The interpolation weights are calculated using the following formula: Where, d jUsing the distance between the interpolation point and the sensor, the three-dimensional velocity field of the entire region is obtained through interpolation. Density field ρ(x,y,z) and velocity field This data will be sent to the control module as input. To ensure data consistency, the control module will perform time alignment on the data from different sensors. The time alignment formula is: t corr =t sensor +Δt offset ; Among them, t sensor Δt represents the time when the sensor data is acquired. offset The time offset between sensors is pre-calibrated using the sensor refresh rate. In this way, the system can acquire complete density field and velocity field data in real time and use them as the basis for subsequent control steps.

[0033] S2. Based on the collected pressure data, determine the low-pressure area, take the low-pressure area as the suction area, and monitor the boundary of the suction area according to the pressure distribution to control the suction force. S2 includes the following steps: Set a pressure threshold and define the area where the pressure is below the threshold as the suction zone; The change in the boundary pressure gradient of the suction domain is calculated to determine whether the topology of the suction domain has changed. When a topological change trend occurs in the suction domain, a suction domain adjustment operation is triggered. The low-pressure region is determined based on a preset pressure threshold. A continuous region with pressure below the threshold is defined as a suction region, and the boundary of the suction region is continuously monitored based on the change in the boundary pressure gradient of the region.

[0034] Specifically, after the negative pressure suction module is activated, the dredging equipment will generate a significant pressure trough in and around the suction port. It can automatically identify this low-pressure area in three dimensions and preset a pressure threshold p. t h, the formula for determining this is as follows: p(x,y,z) <p t h; Where: p(x,y,z) represents the instantaneous pressure value at a spatial point; p t h is a preset pressure threshold. When the area that meets this condition is continuously distributed in space, the system denotes this continuous area as the suction domain Ω. s The mathematical definition can be written as: Ω s ={(x,y,z)∣p(x,y,z) <p t h} Based on the above formula representing the three-dimensional structure of the entire low-pressure region, continuity is determined by connecting adjacent meshes. However, pressure gradient calculations are needed at the suction domain boundary to monitor for topological changes. The suction domain boundary can be defined as the region where the pressure value is near a threshold, taking the form: The system calculates the pressure gradient at the boundary location using the standard gradient formula: in: For the pressure gradient vector, the three partial derivatives are obtained using the finite difference method, with the central difference as follows: The same principle applies to other directions. The magnitude of the pressure gradient is used to determine whether abrupt changes occur at the boundary, and is written as: If G suddenly decreases or abnormally increases at certain locations on the boundary, it indicates that the shape of the suction domain may be changing, or that water backflow in a certain direction is causing a local pressure increase. In this case, the boundary will contract inward. The change in the boundary pressure gradient over time should be recorded. ΔG t =G(t)-G(t-δt); in: G(t) is the boundary gradient at the current time. δt is the time interval; ΔG t This represents the gradient change.

[0035] When the change in pressure gradient at the boundary of the suction domain reaches a preset threshold, it is considered that the suction domain exhibits a topological change trend. The judgment condition is expressed as follows: |ΔG t |>γ; in, γ is the gradient change threshold. When the condition is met, the system believes that the suction domain is about to experience structural fracture or morphological deformation. In this case, the system will trigger suction domain adjustment operations, such as temporarily increasing the negative pressure suction, adjusting the water flow disturbance intensity, or locally correcting the jet angle near the suction port.

[0036] S3. Start the high-pressure water pump and spray high-pressure water jets into the surrounding area of ​​the suction zone through the high-pressure water nozzles to cut and disturb the silt, and adjust the water jet volume according to the density field distribution. S3 includes the following steps: The density diffusion amount is set based on the spatial variation of the density distribution; The sediment accumulation inhibition amount is set based on local sediment content changes; The density source quantity is set based on the gas injection behavior and the source quantity is dynamically adjusted. Based on the deviation distribution between the density field and the target density field, the deviation values ​​at each location are weighted and summarized, and the summarized results are used as the basis for adjusting the gas injection amount.

[0037] Specifically, during dredging operations, sediment particles are affected by different flow velocities, gas jets, and water jets, causing the density field to diffuse or accumulate. The diffusion rate must be set based on the current density field, and the density gradient can be calculated based on the spatial variations of the density field. Therefore, the formula for diffusion amount is: in: D is the density diffusivity; α is the diffusion coefficient, calibrated based on actual environment and experimental data; The gradient of the density field represents the degree to which the density varies with spatial location; In areas with high diffusion, density changes rapidly, indicating a looser distribution of sediment. In areas with low diffusion, sediment is more concentrated, showing a tendency to aggregate near the suction zone boundary. During dredging, sediment aggregation reduces the dredging effect. (Sediment aggregation inhibition amount S) 抑制 The formula can be set based on the changes in sediment concentration and density: in: S 抑制 This represents the amount of sediment accumulation inhibition. β is the adjustment coefficient; C mud The concentration of sediment; ρ is the density of the muddy water; This suppression method reduces the tendency of sediment to accumulate by adjusting the speed of local water flow and the intensity of gas injection, ensuring that sediment is evenly distributed within the dredging area and avoiding the formation of excessively dense sediment deposits in certain areas. Gas injection during the dredging process disturbs the slurry medium and accelerates sediment suspension. The density source quantity Φ... 气 The setting can be determined by the relationship between the amount of gas injected and the density change, using the following formula: in: Φ 气 The amount of gas injected into the source; γ is the gas injection coefficient; Δρ is the deviation between the current density and the target density field; ρ is the density of the mud-water medium in the current region; When there is a large deviation between the current density field and the target density field, the system will increase the gas injection volume to enhance the disturbance effect and promote the suspension of sediment. When the density field approaches the target density, the gas injection volume will gradually decrease. Finally, the system will calculate the deviation Δρ between the density field and the target density field and perform weighted summation of the deviation values ​​at different locations. The purpose of weighted summation is to prioritize areas with large density deviations and adjust the gas injection volume accordingly. The formula for weighted summation is: Δρ 加权 =∑ i w i ·Δρ i ; Where, Δρ 加权 This is the density deviation value after weighted aggregation; w i The weighting coefficient for position i is determined based on factors such as the distance between that position and the boundary of the suction domain, and the local sediment concentration. Δρ i The density deviation at position i; The weighted density deviation value is used to dynamically adjust the gas injection volume Φ 气 : Φ 气 =k·Δρ 加权 ; in: k is an adjustment coefficient, calibrated based on experimental data; By using the above formulas and methods, the amount of gas injected during the dredging process can be precisely controlled, so that the gas injection and sediment disturbance can be better matched with the changes in the density field, thus preventing the dredging efficiency from decreasing due to excessive or insufficient gas injection.

[0038] S3 further includes: during the joint control process, constraining the structure of the suction domain according to the correspondence between the density field, velocity field and pressure field to keep the suction domain continuous; The high-pressure water jet volume is set based on the spatial variation of sediment distribution in the density field to ensure that the jet volume corresponds to the sediment distribution.

[0039] Specifically, the suction domain structure is constrained by the correspondence between the density field, velocity field and pressure field to keep the suction domain continuous and stable. The density field reflects the distribution of sediment, the velocity field reflects the transport direction, and the pressure field determines the boundary state of the suction domain. Based on the correspondence between the three, the system constrains the boundary morphology of the suction domain in real time to avoid the suction domain from breaking or shrinking locally, thereby ensuring that sediment continues to move towards the suction port area. In the joint control system, the system simultaneously monitors the spatial distribution of the density field and sets the high-pressure water jet volume accordingly, ensuring a correspondence between the jet volume and the sediment distribution. When the sediment density increases in a localized area, the system increases the jet volume in that area to promote sediment dispersion and resuspension; when the sediment density decreases, the system reduces the jet volume to avoid excessive disturbance. By ensuring the jet volume corresponds to the density distribution, the system maintains the uniformity of sediment within the suction domain, preventing deformation of the suction domain structure due to local sediment accumulation or sparseness. Through constraint and jet volume matching control, the system achieves continuous maintenance of the suction domain and dynamic stability of sediment distribution during operation, improving the dredging efficiency and flow field consistency under joint control.

[0040] S4. Start the high-pressure air compressor and inject high-pressure gas into the mud-water medium through the high-pressure air nozzle. Set the gas injection amount according to the density field change to adjust the mud and sand distribution and density change. S4 includes the following steps: Set the constraint that the curl of the velocity field is zero; The direction or amount of water jet is adjusted based on the velocity field divergence deviation to ensure that the velocity field meets the curl constraint.

[0041] Specifically, the system first sets a constraint that the curl of the velocity field is zero to limit the formation of a rotational flow structure in the dredging area. When the velocity field exhibits flow around, swirling, or local vortex cores, it can cause sediment to circulate and stagnate near the suction inlet, or flow around laterally, thereby reducing dredging efficiency. Therefore, by using a zero-curvature constraint, the velocity field tends to have a linear distribution, meaning that streamlines mainly converge along the direction of the suction inlet, rather than forming a transverse rotational structure. After setting the irrotation constraint, the system adjusts the water jet direction or jet volume based on the real-time velocity field divergence deviation to ensure that the actual velocity field meets the irrotation constraint requirements. When the divergence is too large, the local water flow diverges outward, weakening the streamline concentration in the suction direction and potentially inducing secondary disturbances. In this case, reducing the jet volume or moderately converging the jet direction can suppress the divergence behavior and allow the water flow to converge back towards the inlet. When the divergence is too small or even negative, excessive convergence of the local fluid can easily lead to a velocity field accumulation effect in front of the inlet, causing sediment to stagnate in local areas. In this case, the system increases the jet volume or adjusts the jet direction to allow the water flow to diffuse appropriately in this area, avoiding local turbulence caused by the compression of dense streamlines. When divergence deviation causes the initial formation of vortices in a local area, that is, when the velocity direction is continuously deflected, the system immediately makes a small and rapid correction to the injection direction. If necessary, the injection volume is increased briefly to disrupt the rotational velocity distribution structure and return the velocity field to an irrotational state. Through the dual control of curl constraint and divergence adjustment, the system can maintain the irrotational, stable and controllable velocity field during the dredging process, so that the silt can enter the suction area along a stable mainstream direction, avoiding flow around, rollback and accumulation, and improving the overall dredging efficiency.

[0042] S4 further includes: adjusting settings including the gas injection location and the gas injection duration; The amount of gas injected is adjusted based on local changes in the density field; The adjustment of the water jet volume is based on the change in the divergence of the velocity field; The change is used to correct the flow rate of the water jet module.

[0043] Specifically, based on the irrotational constraint of the velocity field, the system further adjusts the gas injection position and the gas injection duration to ensure that the gas distribution is consistent with the density field changes. The system adjusts the gas injection amount according to the local changes in the density field. When the density in a certain area increases, the gas injection amount at that position is increased or the injection time is extended to reduce the local density. When the density decreases, the gas injection amount is reduced accordingly, so that the density field can be kept uniformly distributed, which is beneficial to maintaining the stability of the suction domain structure. At the same time, the system adjusts the water jet volume according to the divergence change of the velocity field. The divergence change is used to characterize the degree of local convergence or divergence of water flow. When the divergence increases and shows a divergent trend, the system reduces the water jet volume to suppress excessive divergence. When the divergence decreases or becomes negative and tends to be excessive convergence, the system increases the jet volume to improve local flow stability. The system uses the divergence change to directly correct the flow rate of the water jet module, so that the velocity field maintains irrotational constraints. By jointly adjusting the gas injection position, jet duration, and water jet volume, the gas distribution is consistent with the density field and the water jet behavior is consistent with the velocity field constraints during use, thereby maintaining flow field stability and suction domain structure continuity.

[0044] S5. During the process of water flow and gas jetting, the velocity field distribution is analyzed, and the water jetting direction or jetting amount is adjusted according to the preset velocity field constraints to maintain the specified flow structure of the velocity field. S5 includes the following steps: Construct a set of delay parameters that includes density deviation and density gradient. Feedforward compensation is performed on the negative pressure suction force based on the input quantity corresponding to the delay parameter set; The constraint on the velocity field is achieved by setting the velocity field curl to zero, and the direction of water jet is corrected based on this control condition.

[0045] Specifically, firstly, the set of delay parameters constructed by the system reflects the changing trend of the density field and predicts its hysteresis response. The density deviation represents the difference between the current density and the target density, and the density gradient reflects spatial changes. The system uses these parameters to predict density changes in advance and adjust the suction response to reduce the hysteresis effect. When the density increases, the system increases the negative pressure in advance, and when the density decreases, it decreases the negative pressure. Meanwhile, by setting the control condition that the curl of the velocity field is zero, the system ensures that the fluid does not generate vortices and avoids local disturbances. If the velocity field deviates from this condition, the system corrects the water jet direction according to the deviation to ensure that the water always flows along the suction direction and avoids vortex interference. Through the coordinated control of delay parameter feedforward compensation and velocity field without curl constraint, the system can maintain suction stability in dynamic environments and improve the continuity and response speed of the dredging process.

[0046] S6. Construct a comprehensive control quantity based on the density deviation, water flow change, and pressure change, and adjust the gas injection module, water flow injection module, and negative pressure suction module in a coordinated manner based on the comprehensive control quantity to ensure that the operating parameters of the modules are coordinated.

[0047] S6 includes the following steps: Set a comprehensive control quantity that includes density deviation, water flow change, and negative pressure suction change; The gas injection rate, water injection rate, and negative pressure suction are adjusted in a correlated manner based on the comprehensive control parameters. The comprehensive control quantity consists of density deviation, water flow change, and pressure change. The comprehensive control quantity is used to uniformly set the three types of control quantities: gas injection, water flow injection, and negative pressure suction.

[0048] Specifically, firstly, the system constructs a comprehensive control quantity, which consists of density deviation, water flow variation, and negative pressure suction variation. This quantity reflects the overall state of the current dredging area. Density deviation provides information on sediment distribution changes, water flow variation reflects the need for flow field structure adjustment, and pressure variation corresponds to the trend of negative pressure suction changes. By integrating these three quantities into a single control benchmark, the adjustment targets for gas, fluid, and negative pressure are consistent, avoiding uncoordinated responses caused by independent control items. Based on this comprehensive control quantity, the system performs correlated adjustments on gas injection volume, water injection volume, and negative pressure suction. When the comprehensive control quantity shows an increase in density, a decrease in flow velocity, or a decrease in negative pressure... When conditions are low, the system simultaneously increases gas injection to reduce local density, increases water injection to improve flow field transport, and increases negative pressure to enhance suction. When the integrated control parameters show a decrease in density, a high flow velocity, or excessive negative pressure, the three control parameters are simultaneously reduced to maintain the fluid mixing state and suction intensity within the target range. Through this correlated adjustment, the three types of regulation behaviors can be kept consistent, reducing instability in the flow field or density field caused by deviations in a single control parameter. By setting the integrated control parameters and the correlated adjustment mechanism, gas injection, water injection, and negative pressure suction can be uniformly controlled, improving the coordination and stability of the system in dynamic dredging environments.

[0049] Please see the appendix Figure 2 A green sludge removal system with high-pressure air-water linkage and negative pressure sludge suction, the system includes: Density sensing module, used to acquire the density distribution of mud-water medium; The velocity sensing module is used to acquire the fluid velocity distribution; The negative pressure suction module is used to provide negative pressure suction and form a suction area; Gas injection module, used to inject gas into the target area; Water jet module, used to spray water jets onto target areas; The control module is used to control the gas injection module, water jet module, and negative pressure suction module based on density data, velocity data, and pressure data.

[0050] Specifically, the system collects the density distribution of the mud-water medium through the density sensing module and obtains the fluid motion state in the area through the velocity sensing module. The negative pressure suction module forms a stable suction port in the dredging area to provide basic suction for mud and sand transport. The gas injection module releases gas into the designated area to change the local density stratification and the looseness of the mud and sand. The water injection module injects water into the target area to adjust the local flow direction and transport capacity. The injection volume and injection position are automatically matched according to the changes in the density field and velocity field, respectively. The control module performs comprehensive analysis on real-time data from density, velocity, and pressure, generates corresponding control commands, and synchronously adjusts gas injection, water injection, and negative pressure suction to keep the three types of actions working in synergy. This ensures that the suction field remains continuous and the flow field structure remains stable during use, and maintains the overall controllability of the dredging process.

[0051] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A green dredging method using high-pressure air-water linkage negative pressure sludge suction, characterized in that, Includes the following steps: S1. The sludge removal head, which integrates a high-pressure water nozzle, a high-pressure air nozzle, and a negative pressure sludge suction port, is lowered to the target sludge layer area, and the pressure data of the mud-water medium in the area is collected by the density sensing component and the velocity sensing component. S2. Based on the collected pressure data, determine the low-pressure area, take the low-pressure area as the suction area, and monitor the boundary of the suction area according to the pressure distribution to control the suction force. S3. Start the high-pressure water pump and spray high-pressure water jets into the surrounding area of ​​the suction zone through the high-pressure water nozzles to cut and disturb the silt, and adjust the water jet volume according to the density field distribution. S4. Start the high-pressure air compressor and inject high-pressure gas into the mud-water medium through the high-pressure air nozzle. Set the gas injection amount according to the density field change to adjust the mud and sand distribution and density change. S5. During the process of water flow and gas jetting, the velocity field distribution is analyzed, and the water jetting direction or jetting amount is adjusted according to the preset velocity field constraints to maintain the specified flow structure of the velocity field. S6. Construct a comprehensive control quantity based on the density deviation, water flow change, and pressure change, and adjust the gas injection module, water flow injection module, and negative pressure suction module in a coordinated manner based on the comprehensive control quantity to ensure that the operating parameters of the modules are coordinated.

2. The green dredging method using high-pressure air-water linkage negative pressure sludge suction according to claim 1, characterized in that, The density sensing component in S1 includes a conductivity sensor, and the velocity sensing component includes a flow velocity measurement sensor, which are used to synchronously collect the density and velocity of the mud-water medium at multiple spatial locations. The pressure data includes density distribution and velocity distribution. S1 also includes the following steps: The density of the mud-water medium at various locations within a spatial range is obtained using a conductivity sensor. The three-dimensional velocity field distribution within the spatial range is obtained using a flow velocity measurement sensor.

3. The green dredging method using high-pressure air-water linkage negative pressure sludge suction according to claim 1, characterized in that, S2 includes the following steps: Set a pressure threshold and define the region where the pressure is below the threshold as the suction zone; The change in the boundary pressure gradient of the suction domain is calculated to determine whether the topology of the suction domain has changed. When a topological change trend occurs in the suction domain, a suction domain adjustment operation is triggered. The low-pressure region is determined based on a preset pressure threshold. A continuous region with pressure below the threshold is defined as a suction region, and the boundary of the suction region is continuously monitored based on the change in the boundary pressure gradient of the region.

4. The green dredging method using high-pressure air-water linkage negative pressure sludge suction according to claim 1, characterized in that, S3 includes the following steps: The density diffusion amount is set based on the spatial variation of the density distribution; The sediment accumulation inhibition amount is set based on local sediment content changes; The density source quantity is set based on the gas injection behavior and the source quantity is dynamically adjusted. Based on the deviation distribution between the density field and the target density field, the deviation values ​​at each location are weighted and summarized, and the summarized results are used as the basis for adjusting the gas injection amount.

5. The green dredging method using high-pressure air-water linkage negative pressure sludge suction according to claim 1, characterized in that, S4 includes the following steps: Set the constraint condition that the curl of the velocity field is zero; The direction or amount of water jet is adjusted based on the velocity field divergence deviation to ensure that the velocity field meets the curl constraint.

6. The green dredging method using high-pressure air-water linkage negative pressure sludge suction according to claim 1, characterized in that, S5 includes the following steps: Construct a set of delay parameters that includes density deviation and density gradient. Feedforward compensation is performed on the negative pressure suction force based on the input quantity corresponding to the set of delay parameters; The constraint on the velocity field is achieved by setting the velocity field curl to zero, and the direction of water jet is corrected based on this control condition.

7. The green dredging method using high-pressure air-water linkage negative pressure sludge suction according to claim 1, characterized in that, S6 includes the following steps: Set a comprehensive control quantity that includes density deviation, water flow change, and negative pressure suction change; The gas injection volume, water injection volume, and negative pressure suction are adjusted in a correlated manner based on the aforementioned comprehensive control parameters. The comprehensive control quantity consists of density deviation, water flow change, and pressure change. The comprehensive control quantity is used to uniformly set the three types of control quantities: gas injection, water flow injection, and negative pressure suction.

8. The green dredging method using high-pressure air-water linkage negative pressure sludge suction according to claim 1, characterized in that, The S3 further includes: during the joint control process, constraining the structure of the suction domain according to the correspondence between the density field, velocity field and pressure field, so as to keep the suction domain continuous; The high-pressure water jet volume is set based on the spatial variation of sediment distribution in the density field to ensure that the jet volume corresponds to the sediment distribution.

9. A green dredging method using high-pressure air-water linkage negative pressure sludge suction according to claim 1, characterized in that, The S4 further includes: the adjustment includes setting the gas injection position and the gas injection duration; The amount of gas injected is adjusted based on local changes in the density field; The adjustment of the water jet volume is based on the change in the divergence of the velocity field; The change is used to correct the flow rate of the water jet module.

10. A high-pressure air-water linkage negative pressure sludge suction green dredging system, applied to the high-pressure air-water linkage negative pressure sludge suction green dredging method according to any one of claims 1-9, characterized in that, The system includes: Density sensing module, used to acquire the density distribution of mud-water medium; The velocity sensing module is used to acquire the fluid velocity distribution; The negative pressure suction module is used to provide negative pressure suction and form a suction area; Gas injection module, used to inject gas into the target area; Water jet module, used to spray water jets onto target areas; The control module is used to control the gas injection module, water jet module, and negative pressure suction module based on density data, velocity data, and pressure data.

Images