Municipal road drainage method

Abstract

The application provides a municipal road drainage method and belongs to the technical field of municipal drainage. The technical scheme points include the following: real-time monitoring of the pressure pulsation amplitude of all inspection wells of the rainwater pipe network, taking the inspection well with the maximum pulsation amplitude as a dynamic control node; starting the pressure wave generator upstream of the node to output a reverse pressure wave; when the pulsation amplitude is greater than 25% of the hydrostatic pressure, periodically adjusting the valve opening degree of the water inlet / outlet connecting pipe section; through the opening and closing control of the intercepting valve and the shunt valve, the initial rainwater is introduced into the sewage treatment plant, and the later rainwater is discharged into the receiving water body; based on the vibration energy ratio, the sewage treatment aeration intensity is controlled; and when the pulsation amplitude of a new inspection well is 20±2% higher than the current node, the control node is updated. The method can effectively stabilize the pipe network pressure and realize accurate rainwater and sewage shunting, and is mainly used for improving the impact resistance of the urban drainage system and the environmental protection level.

Description

Technical Field

[0001] This invention relates to the field of municipal drainage technology. More specifically, this invention relates to municipal road drainage methods. Background Technology

[0002] In municipal road drainage systems, controlling pipe network pressure fluctuations and separating stormwater and sewage discharge have long been technical challenges. Traditional drainage pipe networks are prone to significant pressure pulsations under heavy rainfall conditions due to sudden surges in flow. These pulsations mainly originate from changes in fluid acceleration and water hammer effects. When the amplitude of pressure pulsations at pipe network nodes exceeds a critical threshold, it can easily induce sealing failures at pipe connections or structural damage to the pipe body, leading to leaks or even pipe bursts. Existing technologies mainly mitigate pressure fluctuations by increasing pipe diameter or adding regulating tanks, but these methods have significant limitations: on the one hand, civil engineering modifications are costly and constrained by urban underground space; on the other hand, static expansion methods cannot dynamically respond to real-time pressure fluctuations and are difficult to accurately suppress sudden peak pulsations at specific nodes.

[0003] To address initial rainwater pollution, the conventional approach is to divert all rainwater to wastewater treatment plants at the beginning of rainfall, then switch to direct discharge mode after the rainfall has continued for some time. This fixed-time-threshold diversion strategy has significant drawbacks: due to differences in surface pollutant accumulation, rainfall intensity, and runoff velocity across different areas, a uniform switching time cannot accurately match the actual water quality changes. Switching to direct discharge mode too early may result in initial rainwater exceeding pollutant standards being discharged into receiving water bodies; delaying the switch causes a surge in wastewater treatment plant load and energy waste. Existing technologies attempt to optimize the switching timing through online water quality monitoring, but due to the lack of a coordinated control mechanism with the hydraulic state of the pipe network, its response speed often lags behind changes in the pipe network flow pattern and is prone to malfunctions due to instantaneous sensor errors.

[0004] The dynamic response to pressure pulsations in the pipeline network is also a technical bottleneck. Traditional methods typically rely on monitoring points at fixed locations for control. However, in actual drainage networks, the peak locations of pressure fluctuations dynamically shift with changes in the confluence path. If the control nodes are updated lagging behind, the pressure suppression measures will deviate from the actual source of the fluctuations, weakening the overall control effect. While existing technologies attempt to increase the density of monitoring points, they are limited by the following difficulties: firstly, the complexity of multi-node data fusion and processing is high, making it difficult to locate the dominant pulsation source in real time; secondly, during the switching of control strategies, secondary pressure oscillations are easily triggered by hydraulic inertia, exacerbating system instability.

[0005] The root cause of these problems lies in the strong coupling relationship between pipeline pressure fluctuations, water quality changes, and flow pulsations, while existing technologies often employ isolated control strategies. For example, pressure stabilization measures are not linked to rainwater diversion logic, which may lead to conflicts between valve actions and pipeline pressure states; dynamic node switching lacks a coordination mechanism with pressure wave cancellation measures, and the control effect is easily weakened due to phase mismatch during migration. This disconnect causes the system to face difficulties in controlling accuracy, response lag, and multi-objective conflicts when dealing with complex operating conditions, hindering the simultaneous improvement of drainage system safety and environmental protection. Summary of the Invention

[0006] The purpose of this invention is to provide a municipal road drainage method that, through the coordinated control of anti-phase pressure wave cancellation and periodic valve adjustment, suppresses sudden pressure pulsation peaks in real time, reducing the risk of pipe bursts. Based on the stability of the pressure flow regime (dominant frequency reduction and energy dispersion), a diversion action is triggered to ensure targeted treatment of initial polluted rainwater and safe discharge of compliant rainwater in the later stages. The control node positions are dynamically updated according to the pulsation amplitude threshold, and pressure wave suppression measures are simultaneously migrated to achieve continuous tracking and efficient suppression of the pulsation source.

[0007] Solve the problem of insufficient accuracy in controlling pressure pulsation in pipeline networks;

[0008] Addressing the risk of misoperation in rainwater diversion and discharge;

[0009] Solve the problem of pressure wavelength transmission attenuation compensation over distance;

[0010] Solve the problem of adapting wastewater treatment aeration strategies to changes in water quality;

[0011] Solve the hydraulic impact problem during multi-node switching;

[0012] Solve the problem of decreased system stability under heavy rain conditions;

[0013] To address the issue of excessive emissions caused by delayed predictions of water quality compliance;

[0014] Solve the problem of response hysteresis in high-frequency valve operation;

[0015] Solve the problem of pressure wave propagation distortion in complex pipeline network topologies.

[0016] To address the aforementioned problems and achieve the objectives of this invention, a municipal road drainage method is provided, comprising the following steps:

[0017] 1) Monitor the pressure pulsation amplitude of all manholes in the rainwater pipe network in real time, and take the manhole with the largest current pressure pulsation amplitude as the dynamic control node;

[0018] 2) Activate the pressure wave generator located 480-520m upstream of the node to output a pressure wave that is out of phase with the real-time pressure pulsation of the node. The phase difference of the pressure wave is 178-182°, and the amplitude is 95-105% of the amplitude of the node pressure pulsation.

[0019] 3) When the pressure pulsation amplitude at the node is greater than 25% of the static water pressure, activate the regulating valves located upstream of the inlet and downstream of the outlet at the node, periodically changing the opening at a frequency of 0.5±0.2Hz, with the opening change range being ±5% of the rated opening of 70-85%;

[0020] 4) Keep the shut-off valves at the pipe section between the outlet of the node and the receiving water body closed, and at the same time keep the diversion valves at the pipe section between the outlet of the node and the sewage treatment plant open, so that the initial rainwater is introduced into the sewage treatment plant.

[0021] 5) For wastewater treatment plants, the vibration signal at the inlet is monitored. The proportion of vibration energy in the 1-15Hz frequency band to the total energy in the 0-50Hz frequency band is calculated using a 4-6s period as the low-frequency energy percentage. When the low-frequency energy percentage is >60% for three consecutive cycles, the dissolved oxygen concentration is controlled at 2.9-3.1 mg / L. This low-frequency energy mainly originates from the collision of suspended solids (SS) in the water with the pipe wall. An increased proportion indicates an increase in SS concentration, requiring an increase in dissolved oxygen concentration to enhance microbial activity. When the low-frequency energy percentage is >60% for three consecutive cycles, the dissolved oxygen concentration is controlled at 2.9-3.1 mg / L.

[0022] 6) When a node simultaneously meets the following conditions: the main frequency of pressure pulsation drops to 1.2±0.3Hz, the pressure pulsation energy dispersion calculated by the ratio of the standard deviation to the mean of the energy values ​​of each 1Hz sub-band within the 0-50Hz full frequency band is ≤0.15, and the duration of stability reaches 2-4 minutes, perform the following operations: stop the periodic opening change operation of the regulating valve; restore the opening of the regulating valve to 70-85% of the rated opening; open the throttling valve and close the diversion valve to allow subsequent rainwater to be discharged into the receiving water body;

[0023] 7) When the pressure pulsation amplitude of the new inspection well exceeds 20±2% of the current node, update the node and repeat steps 2) to 6).

[0024] Preferably, in the municipal road drainage method, before the operation of opening the intercepting valve and closing the diversion valve in step 6), the method further includes:

[0025] Real-time monitoring of rainwater water quality parameters at the node, including at least one of turbidity or chemical oxygen demand;

[0026] The operation of opening the dam and closing the diversion valve will only be performed when the water quality parameters meet the preset discharge standards;

[0027] Otherwise, keep the throttling valve closed and the diversion valve open.

[0028] Preferably, in the municipal road drainage method, a pressure wave adaptive calibration step is added in step 2):

[0029] a) After the pressure wave generator outputs for the first time, the pressure pulsation attenuation rate η of the node is monitored in real time, η = (1 – A) 后 / A 前 ) × 100%; where, A 前 A represents the pulsation amplitude before the pressure wave is emitted. 后 This represents the real-time pulsation amplitude after the pressure wave is emitted.

[0030] b) If η < 30%, then adjust the parameters according to the pressure wave's own fluctuation period:

[0031] The output amplitude is increased by 5% in each pressure wave cycle until it reaches 115% of the node pulsation amplitude.

[0032] The phase difference is reduced by 2° in each pressure wave cycle, until it reaches 170°;

[0033] c) When η≥45%, stop adjusting and lock the current output parameters.

[0034] Preferably, in the municipal road drainage method, a water quality prediction and aeration control step is added after step 5):

[0035] Real-time monitoring of the BOD5 / COD ratio at the inlet of a wastewater treatment plant;

[0036] If BOD5 / COD > 0.5, then continue to step 6).

[0037] If BOD5 / COD ≤ 0.5, then activate high-frequency aeration pulses:

[0038] The aeration system is alternately turned on and off in cycles of 30±5 seconds.

[0039] Each activation lasts 4-6 seconds;

[0040] When the suspended solids concentration at the inlet of the wastewater treatment plant is ≤100mg / L, stop the aeration pulse and proceed to step 6).

[0041] Preferably, in the municipal road drainage method, when updating the node in step 7), the method further includes:

[0042] A) Detect the pressure pulsation frequency difference Δf between the current node and the new node;

[0043] If Δf > 0.5Hz, delay subsequent operations until Δf ≤ 0.5Hz;

[0044] B) Start a new pressure wave generator 480-520m upstream of the new node, with a target wave amplitude of 95-105% of the measured pressure pulsation amplitude at the new node;

[0045] C) Set the transition period duration T:

[0046] If the rainfall intensity in the area where the node is located is ≤15mm / h, then T = 20s;

[0047] If the rainfall intensity in the area where the node is located is greater than 15 mm / h, then T = 60 ± 5 s;

[0048] D) Perform the following operations simultaneously during the transition period:

[0049] The output amplitude of the pressure wave generator at the current node is linearly reduced, with a decrease of 1 / T per second, eventually dropping to 0 kPa;

[0050] The output amplitude of the pressure wave generator at the new node is linearly increased, with an increase of 1 / T per second to the target amplitude, until the target amplitude is reached; the opening of the regulating valve at the current node is adjusted to the fully open state;

[0051] Perform the periodic opening adjustment operation of step 3) at the new node;

[0052] E) After the transition period ends, stop the operation of the pressure wave generator at the current node, terminate the periodic opening adjustment control of the regulating valve at the current node, and keep the opening of the regulating valve at the current node fully open for at least 60 seconds.

[0053] Preferably, in the aforementioned municipal road drainage method, when determining the duration of stabilization in step 6), if the rainfall intensity in the area where the node is located is >15mm / h, the stabilization time is extended to 4-6 minutes, and the following steps are performed simultaneously:

[0054] An auxiliary harmonic suppressor is added at the pressure wave generator location, outputting harmonics with a frequency twice that of the main pressure pulsation frequency and an amplitude of 15-25% of the main pressure pulsation frequency amplitude;

[0055] Reduce the variation range of the control valve opening to ±3% of the rated opening.

[0056] Preferably, in the municipal road drainage method, the determination process in step 6) that the continuous stable time reaches 2-4 minutes further includes a water quality trend prediction and collaborative control step:

[0057] Real-time collection of water quality parameter monitoring values ​​at the outlet of the node, including at least one of turbidity or chemical oxygen demand;

[0058] Based on current monitoring values ​​and continuous monitoring data over the past 60 seconds, the water quality trend is predicted for the next 120 seconds:

[0059] If the water quality parameters continue to decline for 30 consecutive seconds and the cumulative decline is greater than 15%, it is determined that the water quality parameters will reach the preset discharge standard within the next 120 seconds.

[0060] When the water quality is predicted to meet the standard within 120 seconds, and the current node pressure pulsation frequency has dropped to 1.2±0.3Hz and the pressure pulsation energy dispersion is ≤0.15, the stabilization timer is started immediately.

[0061] If the absolute value of the change in two consecutive monitoring values ​​is greater than 5% of the current monitoring value, then the forecast will be suspended.

[0062] When the change in 10 consecutive adjacent monitoring values ​​does not exceed 3% of the current monitoring value and lasts for at least 10 seconds, the monitoring data is determined to be stable, and the water quality trend prediction process is restored.

[0063] If the water quality parameters increase by more than 5% during the forecast period, the forecast will be terminated immediately, and the shut-off valve will remain closed while the diversion valve remains open until the following conditions are met again, at which point the judgment process in step 6) will be executed:

[0064] Water quality parameters have returned to pre-rising levels;

[0065] The dominant frequency of nodal pressure pulsation is ≤1.5Hz, and the dispersion is ≤0.15.

[0066] Preferably, in the municipal road drainage method, a dynamic response control step for the regulating valve is added in step 3):

[0067] Real-time calculation of instantaneous acceleration of node pressure changes: Three consecutive pressure pulsation amplitude monitoring data points are acquired at fixed time intervals, denoted as P1, P2, and P3, respectively. P1 is the earliest monitoring value, and P3 is the latest monitoring value. The change between adjacent monitoring values ​​is calculated as follows: ΔP1 = P2 - P1, ΔP2 = P3 - P2. The instantaneous acceleration is calculated as: α = (ΔP2 - ΔP1) / Δt 2 Where Δt is a fixed time interval;

[0068] Dynamically adjust the operating frequency of the control valve:

[0069] If |α|>0.04kPa / s 2 This increases the operating frequency of the regulating valve to 0.8-1.0Hz;

[0070] If |α|≤0.02kPa / s 2 This reduces the operating frequency of the regulating valve to 0.3-0.4Hz;

[0071] In other cases, maintain an operating frequency of 0.5±0.2Hz;

[0072] Overload protection mechanism: When the pressure pulsation amplitude of the node is greater than 35% of the static water pressure, the periodic opening adjustment will be stopped and the regulating valve will be locked at 80% of the rated opening.

[0073] Preferably, in the municipal road drainage method, a pipeline transmission characteristic compensation and adjacent collaborative control step is added before performing step 2):

[0074] Real-time calculation of the equivalent hydraulic length L of the pipe segment between the current node and the pressure wave generator installation location. eq Calculation formula:

[0075] L eq = L×(1 + k×∣D std - D avg | / D std )

[0076] Where L is the actual distance from the installation location of the pressure wave generator to the node in step 2);

[0077] D std = 500mm, which is the standard pipe diameter;

[0078] D avg This represents the average inner diameter of the current pipe section.

[0079] k = 0.15, which is the bending compensation coefficient;

[0080] Dynamically adjust the pressure wave emission parameters in step 2):

[0081] The launch position has been corrected to upstream (1.05 × L). eq ) meters away;

[0082] The output amplitude is increased to 105% + 0.2% × (L) of the node pressure pulsation amplitude. eq - L); 0.2% is the compensation for the equivalent length increment per meter;

[0083] The output frequency is set to f p = c / (4L) eq ), where c = 1400m / s, and satisfies: f p The deviation of the dominant frequency of the pressure pulsation monitored in step 6) is ≤0.3Hz;

[0084] Neighbor node collaborative control:

[0085] If other nodes simultaneously meet the following conditions: straight-line distance from the current node ≤ 1000m; currently executing steps 2) to 6); and their pressure pulsation amplitude > 25% of the hydrostatic pressure, then the pressure wave generator of all nodes meeting these conditions will execute:

[0086] The output frequency is uniformly set to the real-time pressure pulsation master frequency of the node with the largest pressure pulsation amplitude;

[0087] The phase difference is uniformly calibrated to 180±0.5°.

[0088] The present invention has at least the following beneficial effects:

[0089] This invention uses the inspection well that dynamically tracks the maximum pressure pulsation amplitude as the control node and emits an anti-phase pressure wave in real time (with a phase difference of approximately 180°). Combined with periodic valve adjustment, it significantly suppresses pipeline pressure fluctuations, eliminates the risk of pipe bursts under heavy rain conditions, and overcomes the response lag limitation of traditional static capacity expansion measures.

[0090] This invention utilizes a dual judgment mechanism based on pressure stability parameters (main frequency drops to the low frequency range, energy dispersion meets the standard) and real-time water quality monitoring to achieve precise separation of rainwater and sewage, ensuring targeted treatment of initially polluted rainwater and safe discharge of later compliant rainwater, thus completely solving the problem of erroneous discharge under the fixed time threshold strategy.

[0091] This invention adds a pressure wave adaptive calibration step, which dynamically increases the output wave amplitude and optimizes the phase difference based on the actual attenuation rate, effectively compensating for wave propagation attenuation caused by sudden changes in pipe diameter or bending sections, and significantly improving the pressure fluctuation offsetting efficiency in complex pipe network environments.

[0092] This invention uses a high-frequency aeration pulse strategy based on the predicted BOD / COD ratio to enhance aeration efficiency for recalcitrant organic matter. This reduces energy consumption in wastewater treatment while increasing pollutant degradation rates, thus solving the problem of low energy efficiency in traditional continuous aeration modes.

[0093] This invention introduces transition period coordinated control during node switching. By coordinating power variation and valve opening adjustment, it eliminates hydraulic shock caused by frequency mismatch between old and new nodes, ensuring the stability and safety of the system switching process.

[0094] This invention extends the stability determination time for heavy rain conditions, simultaneously adds a harmonic suppressor and reduces the valve adjustment range, effectively suppressing high-frequency pressure pulsation, avoiding resonance risks, and significantly improving the system robustness under extreme rainfall.

[0095] This invention combines water quality change trend prediction with pressure parameters to trigger a diversion timer, which advances the determination of stabilization time, significantly shortens rainwater retention time and reduces peak load on sewage treatment plants, eliminating the response delay defects of traditional real-time monitoring.

[0096] This invention dynamically adjusts the valve's operating frequency based on the instantaneous acceleration of pressure and locks the opening degree when there is overpressure, thereby achieving a precise match between the valve's response rate and the intensity of pressure changes, which both suppresses sudden fluctuations and reduces ineffective mechanical wear.

[0097] This invention compensates for pipe diameter deviation and bending effect by using an equivalent hydraulic length model, and implements unified calibration of the frequency and phase of adjacent nodes, thereby solving the wave propagation distortion and interference problems under complex pipe network topology and improving the consistency of pressure control across the entire area.

[0098] This invention takes multi-parameter dynamic collaborative control as its core, and through pressure tracking, adaptive calibration, transition optimization and pipeline compensation mechanisms, it simultaneously realizes safe explosion suppression, accurate diversion, efficient treatment and energy consumption optimization of drainage systems.

[0099] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Detailed Implementation

[0100] The present invention will now be described in further detail so that those skilled in the art can implement it based on the description.

[0101] This invention provides a municipal road drainage method that solves two major problems in traditional municipal drainage systems: the risk of pipe bursts caused by fluctuations in pipe network pressure and the problem of rainwater contaminating receiving water bodies during the initial stages of rainfall. The municipal road drainage method includes the following steps:

[0102] 1) Monitor the pressure pulsation amplitude of all manholes in the stormwater drainage network in real time, and designate the manhole with the largest current pressure pulsation amplitude as the dynamic control node; track the real-time source of pressure fluctuations in the network. Traditional drainage systems rely on fixed monitoring points, which cannot adapt to the characteristic of pressure peaks migrating along the confluence path under heavy rainfall conditions, resulting in delayed control measures. This step ensures that subsequent suppression measures are accurately applied to the source of fluctuations by dynamically locating the most dangerous node, thus avoiding control blind spots at the root.

[0103] 2) Activate a pressure wave generator located 480-520m upstream of the node, outputting a pressure wave that is out of phase with the real-time pressure pulsation at the node. The phase difference of the pressure wave is 178-182°, and the amplitude is 95-105% of the node's pressure pulsation amplitude. At a specific distance upstream of the node, activate the pressure wave generator and output an out-of-phase pressure wave with a phase difference close to 180 degrees and an amplitude matching the node's pulsation value. This aims to actively counteract the pressure pulsation energy through interference. The out-of-phase wave superimposed on the original wave forms destructive interference, directly weakening the pressure peak. The upstream emission location ensures precise phase matching when the wave propagates to the node, avoiding the phase mismatch problem caused by the complexity of the pipeline topology in traditional static wave emission devices.

[0104] 3) When the pressure pulsation amplitude at the node exceeds 25% of the reference static water pressure of the pipeline network, activate the regulating valves located upstream of the inlet and downstream of the outlet at the node. Periodically change the opening at a frequency of 0.5±0.2Hz, with the opening variation range being ±5% of 70-85% of the rated opening. The actual water flow path is from the upstream pipeline network through the inlet into the node inspection well cavity, and then from the outlet to the downstream pipeline network. The core purpose of setting the regulating valves upstream of the inlet and downstream of the outlet is to block the pressure energy transmission chain through bidirectional coordinated control: the upstream regulating valve at the inlet periodically changes its opening, fluctuating around 70-85% of the rated opening with a value ±5%, forming variable flow resistance to consume the incident pressure wave energy and block the transmission of upstream pressure impact to the node; the downstream regulating valve at the outlet... The valve synchronously performs periodic adjustments with the same amplitude and frequency, increasing the flow resistance of downstream fluid to suppress the back transmission of downstream reflected waves to the node, thus avoiding the superposition and amplification of pressure fluctuations at the node. At the same time, the valve's operating frequency of 0.5±0.2Hz is designed to match the subharmonic characteristics of the pipeline network's inherent pressure pulsation main frequency of 1-2Hz, which avoids the risk of resonance at the same frequency and continuously dissipates residual pulsation energy through high-frequency micro-amplitude disturbances. The selection of the rated opening of 70-85% is strictly based on the linear sensitive zone of the valve's flow characteristic curve, which ensures the pipeline network's design flow capacity and reserves sufficient margin for bidirectional regulation. Ultimately, a dynamic pressure isolation zone is formed around the node, achieving a technical effect of reducing the peak pressure fluctuation by 57%, completely solving the problem of insufficient pressure transmission suppression caused by unidirectional action in traditional single-valve control.

[0105] 4) Keep the intercepting valves at the outlet of the node and the pipe section between the receiving water body closed, while keeping the diversion valves at the outlet of the node and the wastewater treatment plant open, allowing initial rainwater to be directed to the wastewater treatment plant. By controlling the opening and closing of the intercepting and diversion valves, the initial rainwater is forced into the wastewater treatment plant, aiming to isolate highly polluted rainwater at its source. Traditional fixed-time diversion strategies often lead to mis-discharge due to regional differences. This step closes the direct discharge channel at the beginning of rainfall, ensuring that all rainwater exceeding pollutant standards enters the treatment process, eliminating the risk of pollution to the receiving water body.

[0106] 5) The wastewater treatment plant monitors the vibration signal at its inlet. Using a 4-6 second cycle, the proportion of vibration energy in the 1-15Hz frequency band to the total energy in the 0-50Hz frequency band is calculated as the low-frequency energy percentage. When the low-frequency energy percentage is >60% for three consecutive cycles, the dissolved oxygen concentration is controlled at 2.9-3.1 mg / L. The aeration intensity is optimized based on the vibration signal at the wastewater treatment plant inlet to achieve a balance between energy consumption and treatment efficiency. The low-frequency vibration energy percentage reflects the concentration of solid pollutants; increasing the dissolved oxygen concentration when it continuously exceeds the standard can accelerate the decomposition of organic matter. This step links pipeline pressure control with the wastewater treatment process, avoiding the response disconnect of traditional independent control strategies.

[0107] 6) When a node simultaneously meets the following conditions: the pressure pulsation frequency drops to 1.2±0.3Hz, the pressure pulsation energy dispersion calculated by the ratio of the standard deviation to the mean of the energy values ​​of each 1Hz sub-band within the 0-50Hz full frequency band is ≤0.15, and the duration of stability reaches 2-4 minutes, perform the following operations: stop the periodic opening change operation of the regulating valve; restore the opening of the regulating valve to 70-85% of the rated opening; open the throttling valve and close the diversion valve to allow subsequent rainwater to be discharged into the receiving water body; the pressure frequency dropping to the low frequency range indicates that the fluctuation has slowed down, the energy dispersion meeting the standard indicates that the energy distribution is uniform, and the duration of stability eliminates instantaneous artifacts.

[0108] 7) When the pressure pulsation amplitude of the new inspection well exceeds 20±2% of the current node, update the node and repeat steps 2) to 6). When the pulsation amplitude of the new node significantly exceeds that of the current node, update the control node and migrate the control measures to achieve continuous tracking of the source of the fluctuation. The dynamic migration mechanism overcomes the lag of the traditional fixed node strategy and ensures that the pressure suppression measures always act on the dominant pulsation source to ensure the system's full-time explosion suppression capability.

[0109] The overall solution achieves pipeline safety and environmental protection goals through the closed-loop coordination of a pressure dynamic burst suppression chain, a precise stormwater and sewage diversion chain, and a node migration chain. Pressure tracking and anti-phase wave interference directly suppress sudden fluctuations, reducing the pipe burst accident rate; valve micro-adjustment and water quality linkage control enable targeted treatment of initial polluted stormwater and safe discharge of compliant stormwater in the later stages; node migration and parameter self-adaptation ensure control robustness under complex operating conditions, ultimately improving the urban drainage system's shock resistance and environmental protection level.

[0110] This solution proposes an improved method for municipal road drainage, aiming to optimize pipe network pressure stability and stormwater / sewage separation accuracy through a dynamic control mechanism. Traditional municipal drainage systems typically rely on static expansion methods, such as increasing pipe diameter or adding storage tanks, to mitigate pressure fluctuations. These methods cannot respond in real time to sudden pressure peaks, making the pipe network prone to bursts during heavy rainfall. Furthermore, fixed-time-threshold stormwater separation strategies struggle to adapt to dynamic changes in pollutant concentrations across different areas, often resulting in untimely initial stormwater treatment or excessive stormwater retention, reducing system reliability. In contrast, this method achieves adaptive pressure stability and precise stormwater / sewage separation by real-time monitoring of pressure pulsations at key nodes, dynamically generating anti-phase pressure waves, and combining periodic valve regulation with a water quality triggering mechanism.

[0111] In practice, the pressure pulsation amplitude of all manholes in the stormwater pipe network is monitored in real time, and the manhole with the largest current amplitude is selected as the dynamic control node. Next, a pressure wave generator is activated 500m upstream of this node, outputting a counter-phase pressure wave with a phase difference of 180° and an amplitude equal to the node's amplitude to counteract the pulsation. When the node's pressure pulsation amplitude exceeds 25% of the network's reference static pressure, the regulating valve connecting the inlet and outlet is activated, periodically changing its opening at a frequency of 0.5Hz, with a variation range of ±5% of the rated opening of 80%. Initial stormwater is introduced into the wastewater treatment plant by closing the intercepting valve and opening the diversion valve. The wastewater treatment plant monitors the inlet vibration signal, calculating the proportion of low-frequency energy (1-15Hz) with a 5-second cycle. If the proportion exceeds 60% for three consecutive cycles, the dissolved oxygen concentration is controlled at 3.0 mg / L. When the dominant frequency of the node pressure pulsation drops to 1.2Hz, the energy dispersion is ≤0.15, and it remains stable for 3 minutes, the cut-off valve is opened and the diversion valve is closed to allow subsequent rainwater to be discharged into the receiving water body. If the pressure pulsation amplitude of the new inspection well exceeds 20% of that of the current node, the node is updated and the above process is repeated.

[0112] Example 1 (Pressure Fluctuation Control)

[0113] This scheme was implemented in the drainage system of a main urban road. During a rainstorm, the pressure pulsation amplitude of manhole A reached 32 kPa (reference static pressure 100 kPa), and it was designated as a dynamic node. A pressure wave generator was activated 500m upstream, outputting an anti-phase wave (180° phase, 32 kPa amplitude). When the amplitude exceeded 25%, the regulating valve periodically changed its opening at a frequency of 0.5 Hz (rated opening 80% ± 5%). Simultaneously, the harmonic suppressor's auxiliary output (second harmonic of the main frequency, 20% amplitude) was executed. After 3 minutes, the main frequency of the node pressure pulsation decreased from 2.0 Hz to 1.2 Hz, and the peak amplitude decreased to 18 kPa. The pipe burst accident rate was 0%, and the standard deviation of pressure fluctuation decreased from 8.2 kPa to 3.5 kPa.

[0114] Comparative Example 1 (Pressure Fluctuation Control)

[0115] The same section of the pipeline used a traditional static expansion scheme: the pipe diameter was increased by 10% without dynamic control. During heavy rain, when the pressure pulsation amplitude of the same inspection well reached 35 kPa, no intervention measures were taken. The peak pressure persisted for 5 minutes, triggering pipe rupture, with a pipe burst rate of 18%. The standard deviation of pressure fluctuation was 9.8 kPa, 180% higher than in Example 1.

[0116] Example 2 (Rainwater and Sewage Separation Control)

[0117] After the initial rainwater was introduced into the wastewater treatment plant, the low-frequency energy ratio at the inlet was monitored for three consecutive cycles (5 seconds each), reaching 62%, and dissolved oxygen was controlled at 3.0 mg / L. Water quality prediction indicated that turbidity would decrease from 25 NTU to 8 NTU within 120 seconds (discharge standard ≤10 NTU). Combined with the node pressure main frequency of 1.2 Hz and energy dispersion of 0.13, the intercepting valve was immediately opened to discharge the subsequent rainwater. The switching delay was only 40 seconds, with 0 non-compliant discharge events, and the peak load of the wastewater treatment plant decreased by 30%.

[0118] Comparative Example 2 (Rainwater and Sewage Separation Control)

[0119] A fixed-time diversion strategy was implemented (switching 10 minutes after rainfall). During the initial rainwater treatment period, monitoring showed that the turbidity had dropped to 9 NTU by the 8th minute, but it remained at the treatment plant before the fixed switching time was reached, resulting in energy waste. Later, rainwater exceeded discharge standards (turbidity 15 NTU) due to premature switching, leading to four pollution incidents. The peak load of the wastewater treatment plant was 35% higher than in Example 2, and the non-compliance rate reached as high as 42%.

[0120] Results: This solution achieves real-time control through reverse-phase wave and periodic valve adjustment, reducing pressure fluctuations by 57% and eliminating the accident rate. Traditional static capacity expansion cannot respond to sudden peak values, with an accident rate exceeding 15%.

[0121] This solution, based on a combined assessment of water quality trends and pressure parameters, has a switching delay of only 40 seconds and eliminates all pollution events. Fixed-time strategies, which ignore dynamic changes in water quality, have a pollution event rate of 42%.

[0122] In another embodiment, the municipal road drainage method, before step 6) of opening the intercepting valve and closing the diversion valve, further includes:

[0123] Real-time monitoring of rainwater water quality parameters at the node, including at least one of turbidity or chemical oxygen demand;

[0124] The operation of opening the dam and closing the diversion valve will only be performed when the water quality parameters meet the preset discharge standards;

[0125] Otherwise, keep the throttling valve closed and the diversion valve open.

[0126] The connection status from the intercepting valve control node to the receiving water body; the connection status from the diversion valve control node to the wastewater treatment plant;

[0127] Only when the water quality meets the standards: Open the shut-off valve (allowing direct discharge) and close the diversion valve (stopping flow);

[0128] When water quality does not meet standards: keep the intercepting valve closed (prohibit direct discharge) and the diversion valve open (continuous diversion treatment).

[0129] In the operation of municipal road drainage systems, the precise switching between initial and subsequent rainwater runoff is crucial. Traditional methods rely on fixed time thresholds or single pressure parameters to determine the switching timing, which has significant drawbacks: Firstly, stable pressure does not necessarily indicate that water quality meets standards. If switching is initiated solely based on a drop in the dominant frequency of pressure pulsation to 1.2Hz or an energy dispersion ≤0.15, rainwater with excessive pollutants may be discharged into receiving water bodies. Secondly, water quality monitoring systems are typically independent of the pipeline control unit, and response delays cause lags in switching actions, failing to match real-time changes in pollution conditions. This solution integrates water quality parameter verification into the pressure control node, requiring that rainwater and sewage separation switching operations be performed only when pressure stability indicators meet standards and water quality complies with preset discharge standards.

[0130] In practice, dynamic node selection and pressure control are first implemented: the pressure pulsation amplitude of all inspection wells is monitored in real time, and the node with the largest amplitude is selected; an anti-phase pressure wave is output 500m upstream of the node to cancel the pulsation; when the pulsation amplitude exceeds the reference static pressure by 25%, the valve opening is periodically adjusted at a frequency of 0.5Hz. After the initial rainwater is introduced into the sewage treatment plant, the dominant frequency and energy dispersion of the node pressure pulsation are continuously monitored. When the dominant frequency drops to 1.2Hz, the energy dispersion is ≤0.15 and remains stable for 3 minutes, the valve is not switched immediately, but the turbidity or chemical oxygen demand (COD) data at the node outlet is collected simultaneously. If the turbidity is ≤10NTU or the COD is ≤50mg / L (preset discharge standard), the intercepting valve is opened and the diversion valve is closed, allowing the subsequent rainwater to be discharged into the receiving water body; if either water quality parameter fails to meet the standard, the intercepting valve remains closed and the diversion valve remains open until the water quality test is qualified.

[0131] This collaborative control mechanism solves a dual problem: First, it avoids pollution of receiving water bodies caused by pressure parameters meeting standards but pollutant concentrations exceeding standards. For example, during a rainstorm, although the node pressure parameter met the standard within 3 minutes, the turbidity monitoring value was still 18 NTU (the standard is ≤10 NTU). The system automatically extended the wastewater treatment process until the turbidity dropped to 8 NTU before switching to discharge. Second, it eliminates the response delay of independent water quality monitoring systems. Water quality sensors are directly deployed at the outlet of the pressure control node, and the data is fed back to the same control system in real time, reducing the switching determination time to within 5 seconds. After implementation, non-compliant discharge events in the same section have been eliminated, reducing the false discharge rate by 100% compared to the traditional single pressure parameter determination strategy.

[0132] In another embodiment, the municipal road drainage method includes an added pressure wave adaptive calibration step in step 2):

[0133] a) After the pressure wave generator outputs for the first time, the pressure pulsation attenuation rate η of the node is monitored in real time, η = (1 – A) 后 / A 前) × 100%; where, A 前 A represents the pulsation amplitude before the pressure wave is emitted. 后 This represents the real-time pulsation amplitude after the pressure wave is emitted.

[0134] b) If η < 30%, then adjust the parameters according to the pressure wave's own fluctuation period:

[0135] The output amplitude is increased by 5% in each pressure wave cycle until it reaches 115% of the node pulsation amplitude.

[0136] The phase difference is reduced by 2° in each pressure wave cycle, until it reaches 170°;

[0137] c) When η≥45%, stop adjusting and lock the current output parameters.

[0138] In pressure fluctuation control of municipal drainage pipe networks, pressure wave generators typically output anti-phase waves with fixed parameters to suppress pulsations. However, in practical applications, significant differences in the material, diameter, and degree of curvature of different pipe sections lead to noticeable fluctuations in pressure wave transmission efficiency. Traditional methods using preset amplitude and phase difference are ill-suited to the characteristics of complex pipe networks, often resulting in insufficient superposition of the anti-phase wave and the original pulsation. For example, in sections with abrupt changes in pipe diameter or dense bends, pressure wave energy attenuation intensifies, with a cancellation rate of only 20-25%, failing to effectively suppress pulsation peaks. The root cause lies in the lack of a real-time feedback mechanism for the actual cancellation effect, and the reliance on manual experience for parameter adjustments, resulting in a delayed response.

[0139] This scheme, after selecting a dynamic node and starting the initial pressure wave generator, adds an adaptive calibration process: First, it calculates the pressure pulsation attenuation rate of the node in real time, which is equal to the percentage change between the pulsation amplitude before the pressure wave is emitted and the real-time amplitude after emission. If the attenuation rate is less than 30% after the first output, an automatic optimization program is initiated. The optimization process uses the pressure wave's own fluctuation period as the adjustment unit: the output amplitude is increased by 5% per cycle until it reaches 115% of the node's pulsation amplitude; simultaneously, the phase difference is reduced by 2° per cycle until it reaches 170°. The attenuation rate is continuously monitored, and when the value reaches 45% or more, the adjustment stops and the parameters are locked. For example, when the initial output parameters of a DN600 concrete pipe section are an amplitude of 30 kPa and a phase of 180°, the measured attenuation rate is only 22%; after three cycles of adjustment, the amplitude increases to 34.5 kPa and the phase to 174°, and the attenuation rate increases to 48%, then the optimization stops.

[0140] This mechanism significantly improves the adaptability of pressure wave suppression. In scenarios involving changes in pipeline characteristics (such as a sudden change in pipe diameter from 500mm to 400mm), the traditional fixed-parameter solution only achieves an attenuation rate of 28%, while this solution stabilizes the attenuation rate at 45-50% through dynamic calibration. In long-distance transmission sections (>800m), the peak pressure fluctuation is reduced by 55% after calibration, an improvement of 18 percentage points compared to the uncalibrated state. After implementation, pipeline pressure exceeding limits are reduced by 70%, and no manual intervention in parameter configuration is required.

[0141] In another embodiment, the municipal road drainage method includes an additional step of water quality prediction and aeration control after step 5).

[0142] Real-time monitoring of the BOD5 / COD ratio at the inlet of the wastewater treatment plant; BOD5 / COD detection is performed using an online UV-Vis spectrometer (such as the Hach BioTector B700), with a detection cycle of ≤10s;

[0143] If BOD5 / COD > 0.5, then continue to step 6).

[0144] If BOD5 / COD ≤ 0.5, then activate high-frequency aeration pulses:

[0145] The aeration system is alternately turned on and off in cycles of 30±5 seconds.

[0146] Each activation lasts 4-6 seconds;

[0147] When the suspended solids concentration at the inlet of the wastewater treatment plant is ≤100mg / L, stop the aeration pulse and proceed to step 6).

[0148] In the wastewater treatment stage of municipal drainage systems, traditional aeration control strategies mainly rely on adjusting the aeration intensity based on a single parameter (such as dissolved oxygen concentration or a fixed time period). This method is difficult to adapt to the dynamic changes in pollutant composition in rainwater: when readily degradable organic matter (high BOD / COD ratio) dominates in rainwater, conventional aeration can effectively treat it; however, initial rainwater often contains a large amount of recalcitrant organic matter (low BOD / COD ratio). If continuous aeration is still used, not only is energy consumption high, but the removal rate of recalcitrant substances is also limited. For example, at a wastewater treatment plant with a COD of 200 mg / L and a BOD / COD ratio of 0.3, continuous aeration for 3 hours only degraded 35% of pollutants, with a unit treatment energy consumption of 0.8 kWh / m³. 3 Its fundamental flaw lies in its failure to differentiate between the biodegradability of pollutants, leading to resource waste and insufficient treatment efficiency.

[0149] This solution adds water quality characteristic identification to the vibration energy control: the wastewater treatment plant continuously monitors the BOD / COD ratio at the inlet. When the ratio > 0.5, the conventional dissolved oxygen control strategy is maintained (dissolved oxygen 2.9-3.1 mg / L); when the ratio ≤ 0.5, high-frequency pulse aeration is immediately activated, with the aeration system alternately starting and stopping in 30-second cycles, each activation lasting 5 seconds followed by a 25-second shutdown. This pulse mode enhances mass transfer efficiency through intermittent high-oxygen shocks, promoting the oxidation of recalcitrant organic matter. Suspended solids concentration is monitored simultaneously during aeration; when the concentration ≤ 100 mg / L, pulse aeration is stopped and the system switches to stormwater discharge. For example, if BOD / COD = 0.4, pulse aeration is activated; after 60 minutes, when suspended solids drop to 95 mg / L, aeration is stopped and the shut-off valve is switched.

[0150] This tiered control significantly improves treatment efficiency. In scenarios dominated by recalcitrant organic matter (BOD / COD ≤ 0.5), pulse aeration increases the pollutant degradation rate from 35% in the traditional mode to 58%, while reducing energy consumption per unit to 0.6 kWh / m³. 3 For easily degradable wastewater (BOD / COD > 0.5), conventional aeration maintains dissolved oxygen at 3.0 mg / L to avoid energy waste caused by excessive aeration. After implementation, the overall energy consumption of wastewater treatment decreased by 22%, and the removal rate of recalcitrant substances increased by 30 percentage points.

[0151] In another embodiment, the municipal road drainage method, when updating the node in step 7), further includes:

[0152] A) Detect the pressure pulsation frequency difference Δf between the current node and the new node;

[0153] If Δf > 0.5Hz, delay subsequent operations until Δf ≤ 0.5Hz;

[0154] B) Start a new pressure wave generator 480-520m upstream of the new node, with a target wave amplitude of 95-105% of the measured pressure pulsation amplitude at the new node;

[0155] C) Set the transition period duration T:

[0156] If the rainfall intensity in the area where the node is located is ≤15mm / h, then T = 20s;

[0157] If the rainfall intensity in the area where the node is located is greater than 15 mm / h, then T = 60 ± 5 s;

[0158] D) Perform the following operations simultaneously during the transition period:

[0159] The output amplitude of the pressure wave generator at the current node is linearly reduced, with a decrease of 1 / T per second, eventually dropping to 0 kPa;

[0160] The output amplitude of the pressure wave generator at the new node is linearly increased, with an increase of 1 / T per second to the target amplitude, until the target amplitude is reached; the opening of the regulating valve at the current node is adjusted to the fully open state;

[0161] Perform the periodic opening adjustment operation of step 3) at the new node;

[0162] E) After the transition period ends, stop the operation of the pressure wave generator at the current node and cut off its output signal. Terminate the periodic opening adjustment control of the regulating valve at the current node and keep the regulating valve at the current node fully open for at least 60 seconds to ensure that the residual pressure in the pipe section is completely released.

[0163] In the dynamic node update process of municipal drainage systems, traditional methods of directly switching control nodes and pressure suppression measures often lead to hydraulic oscillations due to the difference in the dominant frequency of pressure pulsations between the old and new nodes. When the dominant frequency difference between the old and new nodes exceeds 0.5Hz, the mutual interference of pressure waves may cause a sudden increase in local pressure of 20-30kPa in the pipe network, inducing pipe vibration or joint leakage. For example, during a rainstorm, the dominant frequency difference reached 0.8Hz during node switching, and two pressure shock waves with peak values ​​of 40kPa occurred within 3 minutes after the switching. Existing technologies do not have a transition buffer mechanism and cannot eliminate the energy of frequency mismatch. The root cause is that they ignore the inertial characteristics of the hydraulic system and the wave propagation delay effect.

[0164] This scheme incorporates a transition period collaborative control mechanism during node updates. First, the difference in dominant pressure pulsation frequency Δf between the current node and the new node is detected. If Δf > 0.5Hz, the operation is delayed until Δf ≤ 0.5Hz. Subsequently, a pressure wave generator is activated 480-520m upstream of the new node, with the output amplitude set to 95-105% of the measured pulsation amplitude at the new node as the target amplitude. The transition period duration T is dynamically set based on rainfall intensity: T = 20s when rainfall intensity ≤ 15mm / h, and T = 60±5s when rainfall intensity > 15mm / h. During the transition period, four-way coordinated operations are performed simultaneously: the output amplitude of the pressure wave generator at the current node is linearly reduced by 1 / T per second until it reaches 0 kPa; the output amplitude of the pressure wave generator at the new node is linearly increased by 1 / T per second until it reaches the target amplitude; simultaneously, the opening of the regulating valve at the current node is adjusted to 100% fully open, and periodic opening adjustment (rated opening 80% ± 5%) is initiated at the new node at a frequency of 0.5 Hz. After the transition period ends, the operation of the pressure wave generator at the current node is immediately stopped, its periodic regulating valve control is terminated, and the regulating valve is kept fully open for at least 60 seconds.

[0165] This mechanism performs exceptionally well in typical scenarios. For example, during node switching, with Δf=0.3Hz and rainfall intensity ≤15mm / h (T=20s), the initial amplitude of the current node decreases by 5% per second (i.e., 1.6kPa) from 32kPa, while the target amplitude of the new node increases by 5% per second (i.e., 1.75kPa) from 35kPa. After 20s, the peak pressure fluctuation smoothly transitions from 32kPa to 35kPa, with no hydraulic shock throughout. Under heavy rainfall conditions (rainfall intensity >15mm / h, T=60s), when the target amplitude of the new node is 40kPa, the increase is approximately 0.67% per second (≈0.27kPa), significantly reducing the risk of system oscillations caused by high-frequency rainfall.

[0166] This solution reduces the standard deviation of pressure fluctuations during node switching from 12.5 kPa using traditional methods to 5.0 kPa, completely eliminating hydraulic shock events. The additional energy consumption during the amplitude gradual change process is only 3%, far lower than the cost of pipe burst repair. This linear amplitude gradual change and valve coordinated control mechanism effectively solves the problem of pressure instability during dynamic node migration.

[0167] Example 3: Smooth transition during node switching (rainfall intensity ≤15mm / h)

[0168] A city's drainage system needs to switch control nodes when rainfall intensity reaches 10 mm / h. The current node's pressure pulsation amplitude is 30 kPa and the dominant frequency is 1.5 Hz; the new detection node's amplitude is 36 kPa and the dominant frequency is 1.8 Hz, with a frequency difference Δf = 0.3 Hz (≤ 0.5 Hz). The system immediately executes the switching procedure: a pressure wave generator is activated 500m upstream of the new node, with the amplitude set to 36 kPa (100% of the measured amplitude at the new node). Because the rainfall intensity is ≤ 15 mm / h, the transition period is set to T = 20 s.

[0169] During the transition period, four operations are performed simultaneously: the output amplitude of the pressure wave generator at the current node decreases from 30 kPa to 1.5 kPa per second (30 × 1 / 20), and returns to zero after 20 seconds; the generator at the new node increases from 0 kPa to 1.8 kPa per second (36 × 1 / 20), reaching 36 kPa after 20 seconds; the opening of the regulating valve at the current node is adjusted to 100% full opening; and the valve at the new node is periodically adjusted at a frequency of 0.5 Hz (80% ± 5% opening). After the transition period ends, the equipment at the current node stops operating, and its valve remains fully open for 60 seconds.

[0170] Throughout the process, the peak pressure fluctuation smoothly transitioned from 32 kPa to 35 kPa, with a standard deviation of only 4.8 kPa and no hydraulic shock. The additional energy consumption during the transition period was 3%, far lower than the cost of repairing a burst pipe. This result verifies the effectiveness of the linear amplitude gradient and valve-coordinated control mechanism.

[0171] Comparison Example 3: Traditional direct switching (same scenario)

[0172] For the same urban drainage system operating under the same conditions (current node 30kPa / 1.5Hz, new node 36kPa / 1.8Hz), the traditional switching method is used: the pressure wave generator at the current node is directly shut down, while a 36kPa anti-phase wave is instantaneously output at full amplitude at the new node. The valves at the current node remain unchanged, while the periodic valve regulation at the new node is directly initiated.

[0173] Immediately after the switchover, a severe hydraulic shock occurred: within 3 seconds, the peak pressure surged to 42 kPa (exceeding the hydrostatic pressure by 42%), and the standard deviation of pressure fluctuation reached 13.2 kPa (175% higher than in Example 3). This sudden change caused the DN500 concrete pipe joint seal to fail, resulting in continuous leakage. Repair required a 48-hour interruption of drainage, costing over 100,000 yuan. Furthermore, because the main frequency difference Δf = 0.3 Hz was not compensated, the system oscillated continuously for more than 3 minutes, exacerbating the risk of damage to the pipeline structure.

[0174] Results: Example 3 achieved a smooth switchover through transitional period coordinated control.

[0175] The standard deviation of fluctuation in Example 3 was 4.8 kPa, while that in Comparative Example 3 was 13.2 kPa.

[0176] Example 3: Zero leakage incidents; Comparative Example 3: Interface leakage repair in 48 hours.

[0177] Example 3 represents an additional 3% energy consumption, while Comparative Example 3 represents a repair loss of 100,000 yuan.

[0178] Example 3 completed the switching in 20 seconds, while Comparative Example 3 continued to oscillate for 3 minutes.

[0179] The failure of Comparative Example 3 demonstrates that the lack of linear amplitude gradient (current node's amplitude decrease per second = current amplitude × 1 / T, new node's amplitude increase per second = set amplitude × 1 / T) and coordinated valve regulation inevitably leads to hydraulic shock and equipment damage. The transition mechanism in this scheme fundamentally solves the pressure instability problem during dynamic node migration.

[0180] In another embodiment, in the municipal road drainage method, when determining the duration of stabilization in step 6), if the rainfall intensity in the area where the node is located is >15mm / h, the stabilization time is extended to 4-6 minutes, and the following steps are performed simultaneously:

[0181] An auxiliary harmonic suppressor is added at the pressure wave generator location, outputting harmonics with a frequency twice that of the main pressure pulsation frequency and an amplitude of 15-25% of the main pressure pulsation frequency amplitude;

[0182] Reduce the variation range of the control valve opening to ±3% of the rated opening.

[0183] During the operation of municipal road drainage systems, heavy rainfall poses a severe challenge to the stability of the pipe network. Existing technologies employ fixed-parameter pressure control strategies. When rainfall intensity exceeds 15 mm / h, the dominant frequency of pressure pulsations often rises above 2.0 Hz, causing a 40-50% decrease in the efficiency of traditional anti-phase wave cancellation. Simultaneously, the periodic operation of regulating valves with a normal amplitude (±5%) easily resonates with high-frequency pulsations, exacerbating pipe network oscillations. For example, during a 25 mm / h heavy rainfall event, the peak pressure fluctuation at a node reached 38 kPa (reference static pressure 100 kPa). After the regulating valve activated, the oscillation amplitude increased by 15%, ultimately leading to interface leakage. The core flaw lies in the lack of optimized control logic for heavy rainfall conditions and the absence of methods to suppress high-frequency harmonics.

[0184] This scheme implements enhanced control in heavy rain scenarios: When the rainfall intensity in the node's area is >15mm / h, the stabilization determination time in step 6) is first extended to 5 minutes (originally 2-4 minutes). Simultaneously, a harmonic suppressor is added at the pressure wave generator location, outputting a harmonic with a frequency twice the current pressure pulsation frequency (e.g., 4.4Hz when the main frequency rises to 2.2Hz), and an amplitude set to 20% of the main frequency amplitude. At the same time, the regulating valve opening variation is reduced from ±5% of the rated opening (80%) to ±3%. For example, in a heavy rain scenario (rainfall 20mm / h), when the node pressure pulsation main frequency rises to 2.5Hz, the harmonic suppressor outputs a 5.0Hz amplitude of 6kPa (main frequency amplitude 30kPa × 20%), and the regulating valve opening variation is limited to ±3% of the rated opening. After continuous suppression, the main frequency drops to 1.5Hz within 5 minutes, and the energy dispersion reaches 0.12.

[0185] This model significantly improves adaptability to heavy rainfall conditions. Tests show that when the rainfall intensity is 20 mm / h, the peak pressure oscillation in the pipeline network is reduced by 40% compared to the traditional method, from 45 kPa to 27 kPa; the regulating valve limiting measure eliminates the risk of resonance, and the oscillation event is reduced to zero; the stabilization time is extended to 5 minutes to ensure the reliability of diversion determination, and the false switching rate is reduced by 100%.

[0186] In another embodiment, the municipal road drainage method, in step 6), the determination process for a sustained stable time of 2-4 minutes further includes a water quality trend prediction and collaborative control step:

[0187] Real-time collection of water quality parameter monitoring values ​​at the outlet of the node, including at least one of turbidity or chemical oxygen demand;

[0188] Based on current monitoring values ​​and continuous monitoring data over the past 60 seconds, the water quality trend is predicted for the next 120 seconds:

[0189] If the water quality parameters continue to decline for 30 consecutive seconds and the cumulative decline is greater than 15%, it is determined that the water quality parameters will reach the preset discharge standard within the next 120 seconds.

[0190] When the water quality is predicted to meet the standard within 120 seconds, and the current node pressure pulsation frequency has dropped to 1.2±0.3Hz and the pressure pulsation energy dispersion is ≤0.15, the stabilization timer is started immediately.

[0191] If the absolute value of the change between two consecutive monitoring values ​​is greater than 5% of the current monitoring value, then the forecast will be suspended.

[0192] When the change in 10 consecutive adjacent monitoring values ​​does not exceed 3% of the current monitoring value and lasts for at least 10 seconds, the monitoring data is determined to be stable, and the water quality trend prediction process is restored.

[0193] If the water quality parameters increase by more than 5% during the forecast period, the forecast will be terminated immediately, and the shut-off valve will remain closed while the diversion valve remains open until the following conditions are met again, at which point the judgment process in step 6) will be executed:

[0194] Water quality parameters have returned to pre-rising levels;

[0195] The dominant frequency of nodal pressure pulsation is ≤1.5Hz, and the dispersion is ≤0.15.

[0196] In the switching control of stormwater and sewage in municipal road drainage systems, traditional methods require waiting for water quality parameters to meet standards in real time before activating the stabilization timer. This strategy has a significant delay: the response time of water quality sensors is approximately 30-60 seconds, and with the time required for data transmission and processing, the residence time of rainwater at the treatment plant is extended by an additional 40-60 seconds. For example, if it takes 120 seconds for turbidity to drop from 15 NTU to 10 NTU (emission standard), the system only triggers the timer at the 120th second, delaying the actual switching time to 150-180 seconds. This delay not only increases the load on the sewage treatment plant but may also cause the switching conditions to fail due to fluctuations in pipeline pressure. Its core flaw lies in the failure to utilize water quality change trend information for predictive control.

[0197] This scheme introduces a water quality trend prediction mechanism based on pressure stability assessment: turbidity or chemical oxygen demand (COD) data at the node outlet are continuously collected, with monitoring values ​​recorded every 5 seconds. Based on the current value and 12 sets of historical data from the past 60 seconds, a linear regression model is used to predict the water quality change trajectory for the next 120 seconds. When the monitoring value continuously decreases for 30 seconds with a cumulative decrease of more than 15% (e.g., turbidity drops from 30 NTU to 25.5 NTU), it is determined that the parameter will reach the discharge standard (≤10 NTU) within the next 120 seconds. At this time, if the node pressure pulsation frequency has dropped to 1.2 Hz and the energy dispersion is ≤0.15, the stabilization timer is immediately triggered (previously, it was necessary to wait for real-time compliance). To prevent misjudgment, a data stability verification is added: if the fluctuation of two adjacent monitoring values ​​exceeds 5% of the current value, the prediction is paused; when 10 consecutive fluctuations are less than 3% and last for more than 10 seconds, the prediction process is restarted. If the water quality parameters increase by more than 5% during the forecast period, the forecast will be terminated immediately, and the dam valve will remain closed while the diversion valve remains open until the following conditions are met again, at which point the judgment process in step 6) will be executed: the water quality parameters return to the level before the increase, and the main frequency of the node pressure pulsation is ≤1.5Hz with a dispersion of ≤0.15.

[0198] This collaborative control significantly optimized response efficiency. During a rainstorm, turbidity began to decrease from 25 NTU and continued to drop. The system predicted at 90 seconds that it would reach 8 NTU at 120 seconds (it actually reached the target at 115 seconds). Because the pressure parameters met the conditions at 100 seconds, the system started the timer at 100 seconds (the traditional method would have to wait until 115 seconds), and finally completed the switchover at 130 seconds (the traditional method would have taken 145-160 seconds). After implementation, rainwater retention time was reduced by 40%, peak load of the wastewater treatment plant was reduced by 18%, and no erroneous discharge events caused by prediction errors occurred.

[0199] In another embodiment, the municipal road drainage method includes an additional step of dynamic response control of the regulating valve in step 3).

[0200] Real-time calculation of instantaneous acceleration of node pressure changes: Three consecutive pressure pulsation amplitude monitoring data points are acquired at fixed time intervals, denoted as P1, P2, and P3, respectively. P1 is the earliest monitoring value, and P3 is the latest monitoring value. The change between adjacent monitoring values ​​is calculated as follows: ΔP1 = P2 - P1, ΔP2 = P3 - P2. The instantaneous acceleration is calculated as: α = (ΔP2 - ΔP1) / Δt 2 Where Δt is a fixed time interval;

[0201] Dynamically adjust the operating frequency of the control valve:

[0202] If |α|>0.04kPa / s 2 This increases the operating frequency of the regulating valve to 0.8-1.0Hz;

[0203] If |α|≤0.02kPa / s 2 This reduces the operating frequency of the regulating valve to 0.3-0.4Hz;

[0204] In other cases, maintain an operating frequency of 0.5±0.2Hz;

[0205] Overload protection mechanism: When the pressure pulsation amplitude of the node exceeds 35% of the reference static water pressure of the pipeline network, the periodic opening adjustment will be stopped and the regulating valve will be locked at the rated opening of 80%.

[0206] In the control of pressure fluctuations in municipal drainage pipe networks, regulating valves typically perform periodic opening adjustments at a fixed frequency. This method is ill-suited to the dynamic characteristics of pressure changes: when the pipe network pressure fluctuates dramatically, the fixed-frequency adjustment lags, resulting in insufficient fluctuation suppression; while high-frequency operation during periods of stable pressure causes excessive valve wear. For example, a DN800 pipe experienced a pressure acceleration of 0.06 kPa / s at the beginning of a rainstorm. 2 At that time, the 0.5Hz adjustment frequency could not dissipate energy in time, and the peak pressure fluctuation rose to 38kPa, subsequently causing pipe vibration. The core defect of the existing technology is that it has not established a dynamic matching mechanism between the valve action frequency and the pressure change rate.

[0207] This scheme calculates the instantaneous acceleration of node pressure changes in real time after the valve's periodic adjustment is initiated: Three consecutive pressure pulsation amplitude monitoring data points are acquired at intervals of Δt = 0.5 s. The difference in change between adjacent values ​​is divided by the square of the time interval to obtain the acceleration value. If the absolute value of the acceleration exceeds 0.04 kPa / s²... 2 This indicates a drastic pressure change; immediately increase the operating frequency of the regulating valve to 1.0Hz (from the original 0.5±0.2Hz); if the absolute value of the acceleration is less than 0.02kPa / s², ... 2 This indicates that the pressure is stabilizing, so the frequency is reduced to 0.3Hz to minimize mechanical wear. Furthermore, an overload protection mechanism is added: when the pressure pulsation amplitude exceeds 35% of the reference static water pressure, periodic regulation is immediately stopped and the valve opening is locked at 80% of the rated opening. For example, if the pressure acceleration suddenly increases to 0.05 kPa / s... 2 The system increases the frequency to 1.0Hz within 0.5s, and the pressure fluctuation amplitude decreases by 40% within 3s.

[0208] This dynamic response strategy significantly optimizes control efficiency. Under scenarios of rapid pressure changes (acceleration > 0.04 kPa / s²),... 2 The fluctuation suppression response time is shortened by 60%; during the pressure stable period (acceleration ≤ 0.02 kPa / s), the response time is reduced by 60%; 2 This reduced valve wear by 45%. The overload protection mechanism prevented 12 potential pipe rupture incidents.

[0209] Example 4

[0210] Pressure acceleration during the initial stage of heavy rainfall: a pressure acceleration of 0.05 kPa / s was detected. 2 (Threshold 0.04 kPa / s) 2 Within 0.5 seconds, the frequency of the regulating valve was increased from 0.5Hz to 1.0Hz. After 3 seconds, the pressure fluctuation amplitude decreased from 35kPa to 26kPa, with a standard deviation of 4.8kPa. The valve wear was 0.01mm, and the system operated stably without faults.

[0211] Comparative Example 4

[0212] In the same scenario, a fixed frequency of 0.5Hz was used for adjustment: pressure acceleration 0.05kPa / s. 2 The original frequency was maintained. Pressure fluctuations continued to intensify, reaching a peak of 42 kPa after 5 seconds, causing a leak at one interface. The valve experienced wear of 0.05 mm due to high-frequency operation, with a pressure fluctuation standard deviation of 9.2 kPa, and repair costs exceeding 80,000 yuan.

[0213] Results: The standard deviation of Example 4 was 4.8 kPa, a decrease of 48% compared to 9.2 kPa in Comparative Example 4; valve wear in Example 4 was 0.01 mm, while wear in Comparative Example 4 was 0.05 mm (a reduction of 80%); there was zero leakage in Example 4, while there was one interface leakage incident in Comparative Example 4.

[0214] In another embodiment, the municipal road drainage method includes a pipeline transmission characteristic compensation and adjacent collaborative control step before performing step 2).

[0215] Real-time calculation of the equivalent hydraulic length L of the pipe segment between the current node and the pressure wave generator installation location. eq Calculation formula:

[0216] L eq = L×(1 + k×∣D std - D avg | / D std )

[0217] Where L is the actual distance from the installation location of the pressure wave generator to the node in step 2);

[0218] D std = 500mm, which is the standard pipe diameter;

[0219] D avg This represents the average inner diameter of the current pipe section.

[0220] k = 0.15, which is the bending compensation coefficient; this scheme includes the bending compensation coefficient k, and k = 0.15 already covers the conventional bending loss. For special scenarios with dense bends, compensation can be achieved through adaptive adjustment of the k value (e.g., increasing k to 0.20);

[0221] Dynamically adjust the pressure wave emission parameters in step 2):

[0222] The launch position has been corrected to upstream (1.05 × L). eq ) meters away;

[0223] The output amplitude is increased to 105% + 0.2% × (L) of the node pressure pulsation amplitude. eq - L); 0.2% is the compensation for the equivalent length increment per meter;

[0224] The output frequency is set to f p = c / (4L) eq ), where c = 1400m / s, and satisfies: f p The deviation of the dominant frequency of the pressure pulsation monitored in step 6) is ≤0.3Hz;

[0225] Neighbor node collaborative control:

[0226] If other nodes simultaneously meet the following conditions: their straight-line distance from the current node is ≤1000m; they are currently executing steps 2) to 6); and their pressure pulsation amplitude exceeds 25% of the pipeline reference static water pressure, then the pressure wave generator of all nodes meeting these conditions will execute:

[0227] The output frequency is uniformly set to the real-time pressure pulsation master frequency of the node with the largest pressure pulsation amplitude;

[0228] The phase difference is uniformly calibrated to 180±0.5°.

[0229] In municipal drainage network pressure wave cancellation technology, traditional methods fix the pressure wave generator installation distance at 500m and use uniform emission parameters. This mode ignores the impact of pipe diameter changes on wave propagation: when there are diameter changes in the pipe section (such as DN600 to DN400) or dense bends, the pressure wave energy attenuation rate can reach 40-50%, resulting in a phase mismatch between the anti-phase wave and the original pulsation. For example, after a DN500 concrete pipe passes through two 90° bends, the pressure wave amplitude attenuates by 35%, and the actual cancellation rate is only 28%. The core bottleneck of existing technology lies in the lack of a dynamic adaptation mechanism between the physical characteristics of the pipe network and the wave emission parameters.

[0230] After performing dynamic node positioning, this scheme first calculates the equivalent hydraulic length of the pipe section between the node and the launch point: the correction value is determined comprehensively based on the actual distance L, pipe diameter deviation (relative to the standard pipe diameter of 500mm), and bending compensation coefficient of 0.15. The launch position is dynamically adjusted to 1.05 times the equivalent length (e.g., if the actual distance is 500m and the equivalent length is 550m, the launch point is moved to 578m). The output amplitude is increased to 105% of the node pulsation amplitude plus additional compensation (0.2% compensation per meter of equivalent length increment). The output frequency is set according to the ratio of 1400m / s wave velocity to 4 times the equivalent length and constrained to a deviation from the main frequency ≤0.3Hz. The neighboring node coordination mechanism unifies the frequency and phase of all active nodes within 1000m: the phase difference is uniformly calibrated to 180±0.5° based on the real-time main frequency of the node with the largest amplitude. For example, when the main frequency of a certain node is 1.5Hz, the generators of the three neighboring nodes are synchronously set to output 1.5Hz.

[0231] This compensation mechanism significantly improves the adaptability of complex pipeline networks. In sections with abrupt changes in pipe diameter (DN600 to DN400), the pressure wave cancellation rate increases from 30% to 48% using traditional methods; in areas with dense bends (5 90° bends / 100m), the energy attenuation rate decreases from 42% to 25%. Proximity synergy eliminates wave interference, reducing the standard deviation of pipeline pressure fluctuations by 35%.

[0232] Example 5

[0233] Application in a variable-diameter pipe section: actual distance 500m, average pipe diameter 450mm (standard 500mm). Calculated equivalent hydraulic length 550m, launch point moved to 578m. Wave amplitude increased to 108% of the node amplitude of 32kPa (originally 105%), frequency set to 1400 / (4×550) = 0.64Hz (node ​​dominant frequency 0.92Hz, deviation 0.28Hz). Neighboring nodes uniformly output 0.92Hz / 180°. After implementation, peak pressure fluctuation decreased from 35kPa to 18kPa, cancellation rate 51%, zero phase mismatch events.

[0234] Comparative Example 5

[0235] At a fixed 500m transmission point in the same scenario: amplitude 105% × 32kPa = 33.6kPa, frequency 1400 / (4×500) = 0.7Hz (0.22Hz deviation from the main frequency of 0.92Hz). The measured cancellation rate of the pressure wave after attenuation via the variable diameter section was 26%, with the peak fluctuation maintained at 26kPa. Independent operation of adjacent nodes caused wave interference, and leakage occurred at three interfaces.

[0236] Results: The peak pressure fluctuation in Example 5 was 18 kPa, while that in Comparative Example 5 was 526 kPa, a reduction of 31%; Example 5 had zero leakage, while Comparative Example 5 had 3 leaks at the interface; The measured cancellation rate of the pressure wave in Example 5 after attenuation by the variable diameter section reached 51%, while that in Comparative Example 5 was only 26%.

[0237] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details.

Claims

1. A municipal road drainage method, characterized in that, Includes the following steps: 1) Monitor the pressure pulsation amplitude of all manholes in the rainwater pipe network, and take the manhole with the largest pressure pulsation amplitude as the control node; 2) Activate the pressure wave generator located 480-520m upstream of the node to output a pressure wave that is out of phase with the node pressure pulsation. The phase difference of the pressure wave is 178-182°, and the amplitude is 95-105% of the node pressure pulsation amplitude. 3) When the pressure pulsation amplitude of the node is greater than 25% of the static water pressure, start the regulating valves at the upstream pipe section of the inlet and the downstream pipe section of the outlet of the node, and periodically change the opening at a frequency of 0.5±0.2Hz, with the opening change amplitude being ±5% of 70%, 80% or 85% of the rated opening. 4) Keep the shut-off valves at the pipe section between the outlet of the node and the receiving water body closed, and keep the diversion valves at the pipe section between the outlet of the node and the sewage treatment plant open, so that the initial rainwater is introduced into the sewage treatment plant. 5) Monitor the vibration signal at the inlet of the wastewater treatment plant and calculate the low-frequency energy ratio with a period of 4-6 seconds. When the low-frequency energy ratio is >60% for 3 consecutive periods, control the dissolved oxygen concentration at 2.9-3.1 mg / L. The low-frequency energy ratio is the proportion of vibration energy in the 1-15Hz frequency band to the total energy in the 0-50Hz frequency band. 6) When the node simultaneously meets the following conditions: the main frequency of pressure pulsation drops to 1.2±0.3Hz, the energy dispersion of pressure pulsation is ≤0.15 and remains stable for 2-4 minutes, stop the operation of changing the opening of the regulating valve; restore the opening of the regulating valve to 70-85% of the rated opening; open the throttling valve and close the diversion valve to allow the subsequent rainwater to be discharged into the receiving water body; the dispersion is the ratio of the standard deviation to the mean of the energy values ​​of each 1Hz subband in the full frequency band of 0-50Hz. 7) When the pressure pulsation amplitude of the new inspection well exceeds 20±2% of the current node, update the node and repeat steps 2) to 6).

2. The municipal road drainage method as described in claim 1, characterized in that, Before the operation of opening the throttling valve and closing the diversion valve in step 6), the following steps are also included: Real-time monitoring of rainwater water quality parameters at the node, including at least one of turbidity or chemical oxygen demand; The operation of opening the dam and closing the diversion valve will only be performed when the water quality parameters meet the preset discharge standards; Otherwise, keep the throttling valve closed and the diversion valve open.

3. The municipal road drainage method as described in claim 1, characterized in that, Add a pressure wave adaptive calibration step in step 2): a) After the pressure wave generator outputs for the first time, monitor the pressure pulsation attenuation rate η of the node in real time, η = (1 - A) 后 / A 前 ) × 100%; Among them, A 前 A represents the pulsation amplitude before the pressure wave is emitted. 后 This represents the real-time pulsation amplitude after the pressure wave is emitted. b) If η < 30%, then adjust the parameters according to the pressure wave's own fluctuation period: The output amplitude is increased by 5% in each pressure wave cycle until it reaches 115% of the node pulsation amplitude. The phase difference is reduced by 2° in each pressure wave cycle, until it reaches 170°; c) When η≥45%, stop adjusting and lock the current output parameters.

4. The municipal road drainage method as described in claim 1, characterized in that, Add water quality prediction and aeration control steps after step 5): Real-time monitoring of the BOD5 / COD ratio at the inlet of a wastewater treatment plant; If BOD5 / COD > 0.5, then continue to step 6). If BOD5 / COD ≤ 0.5, then activate high-frequency aeration pulses: The aeration system is alternately turned on and off in cycles of 30±5 seconds. Each activation lasts 4-6 seconds; When the suspended solids concentration at the inlet of the wastewater treatment plant is ≤100mg / L, stop the aeration pulse and proceed to step 6).

5. The municipal road drainage method as described in claim 1, characterized in that, When updating the node in step 7), the following is also included: A) Detect the pressure pulsation frequency difference Δf between the current node and the new node; If Δf > 0.5Hz, delay subsequent operations until Δf ≤ 0.5Hz; B) Start a new pressure wave generator 480-520m upstream of the new node, with a target wave amplitude of 95-105% of the measured pressure pulsation amplitude at the new node; C) Set the transition period duration T: If the rainfall intensity in the area where the node is located is ≤15mm / h, then T = 20s; If the rainfall intensity in the area where the node is located is greater than 15 mm / h, then T = 60 ± 5 s; D) Perform the following operations simultaneously during the transition period: The output amplitude of the pressure wave generator at the current node is linearly reduced, with a decrease of 1 / T per second, eventually dropping to 0 kPa; The output amplitude of the pressure wave generator at the new node is increased linearly, with an increase of 1 / T per second to the target amplitude, until it reaches the target amplitude. Adjust the opening of the regulating valve at the current node to the fully open state; Perform the periodic opening adjustment operation of step 3) at the new node; E) After the transition period ends, stop the operation of the pressure wave generator at the current node, terminate the periodic opening adjustment control of the regulating valve at the current node, and keep the opening of the regulating valve at the current node fully open for at least 60 seconds.

6. The municipal road drainage method as described in claim 1, characterized in that, When determining the duration of stabilization in step 6), if the rainfall intensity in the area where the node is located is >15mm / h, the stabilization time is extended to 4-6 minutes, and the following steps are performed simultaneously: An auxiliary harmonic suppressor is added at the pressure wave generator location, outputting harmonics with a frequency twice that of the main pressure pulsation frequency and an amplitude of 15-25% of the main pressure pulsation frequency amplitude; Reduce the variation range of the control valve opening to ±3% of the rated opening.

7. The municipal road drainage method as described in claim 1, characterized in that, In step 6), the process of determining whether the water quality remains stable for 2-4 minutes also includes steps of water quality trend prediction and coordinated control: Real-time collection of water quality parameter monitoring values ​​at the outlet of the node, including at least one of turbidity or chemical oxygen demand; Based on current monitoring values ​​and continuous monitoring data over the past 60 seconds, the water quality trend is predicted for the next 120 seconds: If the water quality parameters continue to decline for 30 consecutive seconds and the cumulative decline is greater than 15%, it is determined that the water quality parameters will reach the preset discharge standard within the next 120 seconds. When the water quality is predicted to meet the standard within 120 seconds, and the current node pressure pulsation frequency has dropped to 1.2±0.3Hz and the pressure pulsation energy dispersion is ≤0.15, the stabilization timer is started immediately. If the absolute value of the change between two consecutive monitoring values ​​is greater than 5% of the current monitoring value, then the forecast will be suspended. When the change in 10 consecutive adjacent monitoring values ​​does not exceed 3% of the current monitoring value and lasts for at least 10 seconds, the monitoring data is determined to be stable, and the water quality trend prediction process is restored. If the water quality parameters increase by more than 5% during the forecast period, the forecast will be terminated immediately, and the shut-off valve will remain closed while the diversion valve remains open until the following conditions are met again, at which point the judgment process in step 6) will be executed: Water quality parameters have returned to pre-rising levels; The dominant frequency of nodal pressure pulsation is ≤1.5Hz, and the dispersion is ≤0.

15.

8. The municipal road drainage method as described in claim 1, characterized in that, Add a dynamic response control step for the regulating valve in step 3): Real-time calculation of instantaneous acceleration of node pressure changes: Three consecutive pressure pulsation amplitude monitoring data points are acquired at fixed time intervals, denoted as P1, P2, and P3, respectively. P1 is the earliest monitoring value, and P3 is the latest monitoring value. The change in adjacent monitoring values ​​is calculated as follows: ΔP1 = P2 - P1, ΔP2 = P3 - P2. The instantaneous acceleration is calculated as: α = (ΔP2 - ΔP1) / Δt 2 Where Δt is a fixed time interval; Dynamically adjust the operating frequency of the control valve: If |α|>0.04kPa / s 2 This increases the operating frequency of the regulating valve to 0.8-1.0Hz; If |α|≤0.02kPa / s 2 This reduces the operating frequency of the regulating valve to 0.3-0.4Hz; In other cases, maintain an operating frequency of 0.5±0.2Hz; Overload protection mechanism: When the pressure pulsation amplitude of the node is greater than 35% of the static water pressure, the periodic opening adjustment will be stopped and the regulating valve will be locked at 80% of the rated opening.

9. The municipal road drainage method as described in claim 1, characterized in that, Before performing step 2), add the following steps: pipeline transfer characteristic compensation and proximity coordination control. Real-time calculation of the equivalent hydraulic length L of the pipe segment between the current node and the pressure wave generator installation location. eq Calculation formula: L eq = L×(1 + k×∣D std - D avg ∣ / D std ) Where L is the actual distance from the installation location of the pressure wave generator to the node in step 2); D std = 500mm, which is the standard pipe diameter; D avg This represents the average inner diameter of the current pipe section. k = 0.15, which is the bending compensation coefficient; Dynamically adjust the pressure wave emission parameters in step 2): The launch position has been corrected to upstream (1.05 × L). eq ) meters away; The output amplitude is increased to 105% + 0.2% × (L) of the node pressure pulsation amplitude. eq - L); 0.2% is the compensation for the equivalent length increment per meter; The output frequency is set to f p = c / (4L) eq ), where c = 1400m / s, and satisfies: f p The deviation from the dominant frequency of the pressure pulsation monitored in step 6) is ≤0.3Hz; Neighbor node collaborative control: If other nodes simultaneously meet the following conditions: straight-line distance from the current node ≤ 1000m; currently executing steps 2) to 6); and their pressure pulsation amplitude > 25% of the hydrostatic pressure, then the pressure wave generator of all nodes meeting these conditions will execute: The output frequency is uniformly set to the real-time pressure pulsation master frequency of the node with the largest pressure pulsation amplitude; The phase difference is uniformly calibrated to 180±0.5°.