163 results about "Cavitation erosion" patented technology

The invention provides a dynamic grid-based cavitation erosion and secondary cavitation erosion prediction method, and belongs to the technical field of fluid machinery and cavitation flow simulation. The prediction method comprises the following steps: carrying out parameter measurement on a deformed engineering material, selecting a computational domain of the deformed engineering material, and carrying out grid division on the computational domain; determining boundary conditions, gas-liquid phase physical property parameters and a mass transfer rate between liquid and gas caused by cavitation; calculating collapse energy, and performing node movement on the gridded computational domain to simulate damage caused by the collapse energy; according to the method, the fluid volume method is used for capturing a multi-phase interface, the cavitation model is used as the basis, the cavity collapse release impact energy is subjected to prediction calculation and converted into distribution of point-shaped cavitation pits with different depths and radiuses on the surface of the model, and the cavitation distribution is predicted according to the collapse energy. And the cavitation erosion collapse on the surface of the prediction model is more visual and accurate.

The invention discloses an inducer cavitation erosion resistance optimization design method based on an optimal meta model, which is applied to the technical field of pump inducer optimization design. Determining an inducer hydraulic performance simulation model by adjusting the coefficient of the cavitation model, and determining a cavitation calculation model by comparing the cavitation prediction error of the existing cavitation calculation model based on the unsteady numerical simulation result of the hydrofoil; on the basis of a small sample test design method, geometric parameters with the influence weight on the cavitation erosion area and the pump performance larger than a preset influence weight threshold value are determined, a hydraulic performance simulation model and a cavitation erosion calculation model are used for prediction, and a sample database is established; and training different meta-models based on the sample database, determining the meta-model with the best prediction precision, and solving the meta-model by using a global optimization algorithm. According to the induction wheel, the cavitation erosion phenomenon of the induction wheel can be effectively avoided, and the cavitation erosion resistance of the induction wheel is improved.

The invention discloses a cavitation erosion strength prediction method and system coupled with a multi-scale material model, relates to the technical field of engineering computational fluid mechanics, and aims to solve the problem that the influence of material response cannot be considered in cavitation erosion assessment of a hydraulic machinery overflow pipeline in the prior art. Calculating the macroscopic evolution process of the cavitation bubbles in the cavitation flow field by using the cavitation model to obtain macroscopic evolution information of the cavitation bubbles, and converting all small cavitation bubbles into single bubbles according to the macroscopic evolution information; and calculating the microcosmic dynamic process of the single bubble to obtain microcosmic dynamic information, calculating the impact load of the single bubble according to the microcosmic dynamic information, and synthesizing the impact load of the single bubble in all time steps to calculate the material cavitation erosion incubation period of the overflowing pipeline, namely the cavitation erosion strength. According to the method, the dynamic evolution process of large-scale cavitation bubbles and small-scale cavitation bubbles can be described at the same time, and the cavitation erosion strength forecasting is spanned from qualitative to quantitative.

The present invention discloses a method and device for numerical simulation of near-wall single cavitation collapse coupled with boundary motion, comprising: step 1, introducing a physical model of a near-wall single cavitation into a pre-constructed external flow field to obtain a corresponding flow field physical model; step 2, meshing the flow field physical model; setting initial conditions and flow field boundary conditions, and setting a time step that meets the calculation requirements; step 3, setting specific calculation parameters for solving the flow field process, and introducing a fluid volume method to capture the gas-liquid interface; step 4, applying wall vibration in the form of a user-defined function to simulate the cavitation dynamics behavior under vibration impact. The present invention takes into account the influence of wall vibration in the numerical simulation process by coupling boundary motion, and realizes the simulation of the dynamics behavior of near-wall single cavitation under vibration impact conditions. On this basis, the influence of conditions such as vibration frequency on the cavitation collapse process can be further explored, providing theoretical guidance for optimized cavitation suppression design.

The invention belongs to the technical field of industrial automation control, and particularly relates to a control system and method of a battery shell cleaning machine, and the method comprises the steps: obtaining a sound field signal in a cleaning tank, and carrying out the preprocessing to remove direct current drift and low-frequency mechanical vibration; the permutation entropy of the sound field signals is calculated to evaluate load complexity, a penalty factor of variational mode decomposition is adaptively constructed according to the load complexity, and then a fundamental frequency mode and a high frequency mode are separated; constructing a risk index reflecting the cavitation erosion degree according to the energy ratio of the high-frequency mode and the time domain volatility of the high-frequency mode; and according to the deviation between the risk index and the safety threshold, cooperatively adjusting the frequency jitter amplitude and the power amplitude of the ultrasonic generator. According to the method, through a self-adaptive decoupling damage signal and double-variable cooperative control strategy, on the premise that high cleaning efficiency is guaranteed, destructive cavitation and resonance damage are effectively restrained, and the balance between the cleaning effect and workpiece safety is achieved.

The invention discloses a corrosion-resistant cavitation-erosion-resistant self-repairing marine protective coating suitable for a high-temperature environment and a preparation method thereof, belongs to the technical field of marine protective coatings, and aims to further improve the comprehensive performance of existing self-repairing polyurethane. FA-FGE diol is used as a chain extender, and on the basis of a DA bond, the corrosion-resistant cavitation-erosion-resistant self-repairing marine protective coating suitable for the high-temperature environment and the preparation method of the corrosion-resistant cavitation-erosion-resistant self-repairing marine protective coating are prepared. A hydrogen bond is used as a supplement to adjust the content of a chain extender according to different molar ratios, and is introduced into a PU system to obtain self-repairing performance. The dopamine is used for performing surface modification on the carbon nano tube, so that the binding property and the dispersity of the dopamine modified carbon nano tube and a polyurethane interface are improved, and the overall protection performance of the material is improved. Tests show that the material toughness of the coating can reach 356 MJ / m < 3 >, and the tensile strength can reach 72 MPa. Compared with previous reports, the corrosion resistance and cavitation erosion resistance are remarkably improved, the self-healing rate under infrared light for 90 s is 93%, and the self-healing rate after repeating for 3 times is 81%.

The invention discloses an elastic material hydrofoil fluid-solid coupling cavitation erosion forecasting method based on a potential energy theory, and belongs to the field of computational fluid mechanics and cavitation. The implementation method comprises the following steps: simulating the cavitation of the hydrofoil made of the elastic material by using a tight coupling algorithm to obtain the pressure and steam volume fraction distribution of the surface of the hydrofoil; a steam volume fraction distribution based on pressure; constructing an erosion index correction factor F for representing the bending torsional deformation degree of the elastic material hydrofoil to correct the cavitation erosion index represented by the pressure wave power density; the cavitation erosion indexes larger than a threshold value are screened out, and the final cavitation erosion risk index is a quotient after superposition of the cavitation erosion indexes; the corrected cavitation erosion index data are interpolated into RGB color data, the data serve as a geometric structure model of a fourth-dimensional mapping elastic material hydrofoil, and the corrected cavitation erosion index numerical value is represented through color change. The corrected cavitation erosion index can more accurately forecast a cavitation erosion risk part on the surface of the hydrofoil made of the elastic material.

The invention discloses a water turbine cavitation fault diagnosis method based on vibration monitoring, and the method comprises the steps: obtaining water turbine signals, carrying out the data combination of the water turbine signals through machine learning, obtaining to-be-matched data, carrying out the preprocessing of the to-be-matched data, and obtaining first data; constructing a machine learning model based on cavitation and cavitation erosion classification by using the first data; according to the built machine learning model based on cavitation and cavitation erosion classification, the operation state of the water turbine is detected, when the cavitation state of the water turbine is abnormal, an early warning signal is sent out, and the early warning signal is converted into a configuration output signal of a water turbine vibration detection protection module; the intelligent and automatic monitoring mode can reduce the frequency and intensity of manual inspection and improve the working efficiency.

The invention relates to a rapid measurement method and device for cavitation damage of a water turbine runner and computer equipment. The method comprises the following steps: acquiring point cloud data collected by a 3D laser scanner for the surface of the turbine runner; determining a cavitation erosion area according to geometric features of the point cloud data; according to the point cloud data corresponding to the cavitation erosion area, the cavitation erosion damage area, the cavitation erosion damage depth and the cavitation erosion damage volume are determined; and according to the cavitation erosion area, the cavitation erosion damage area, the cavitation erosion damage depth and the cavitation erosion damage volume, determining a cavitation erosion damage measurement result of the water turbine runner. According to the method, based on the characteristics of high precision and interference resistance of the 3D laser scanner, the area with cavitation erosion is determined by using the acquired point cloud data, the area, depth and volume of the cavitation erosion area are calculated, an accurate cavitation erosion damage measurement result of the water turbine runner is generated, the limitation of a detection environment and an operation condition on cavitation erosion damage detection is avoided, and the accuracy of the detection result is improved. And efficient cavitation damage detection is realized, so that the safety of the hydroelectric equipment is improved.

The invention discloses a near-wall single-cavity collapse numerical simulation method and device coupled with boundary motion, and the method comprises the steps: 1, introducing a near-wall single-cavity physical model into a pre-constructed external flow field, and obtaining a corresponding flow field physical model; step 2, carrying out grid division on the flow field physical model; setting an initial condition and a flow field boundary condition, and setting a time step length meeting a calculation requirement; 3, setting specific calculation parameters in the process of solving the flow field, and introducing a fluid volume method to capture a gas-liquid interface; and 4, applying wall surface vibration in the form of a user-defined function, and simulating cavitation dynamic behaviors under vibration impact. According to the method, the influence of wall surface vibration is considered in the numerical simulation process in a mode of coupling boundary motion, the simulation of the dynamic behavior of the near-wall single cavitation bubble under the vibration impact condition is realized, and the influence of conditions such as vibration frequency on the cavitation bubble collapse process can be further explored on the basis; and theoretical guidance is provided for optimized cavitation inhibition design.

The invention discloses an inducer efficient anti-cavitation numerical optimization method based on blade reverse parameterization, and relates to the technical field of optimization design of inducers for pumps, the inducer is designed and machined through five-axis linkage numerical control, and meanwhile, an inducer visual cavitation test testbed is built; hydraulic performance and cavitation erosion tests are carried out through a test bed, and curves of lift, efficiency, net positive suction head and cavitation erosion area changing along with time are obtained; finding an inducer turbulence model, an inducer cavitation model and a cavitation erosion calculation model with the minimum calculation error; carrying out reverse parametric modeling on the inducer blade; building an inducer parameterized intelligent computing platform based on modeling; screening main geometric parameters of the inducer; optimizing the inducer based on the turbulence model, the cavitation model, the cavitation erosion model and the intelligent computing platform; and performing hydraulic performance test and cavitation erosion test verification on the optimized inducer. The anti-cavitation performance of the inducer can be effectively improved.

The invention belongs to the technical field of engine detection, and particularly relates to a detection method and system for a heavy-load engine coolant cavitation erosion bench test, and the detection method comprises the following steps: S1, injecting a coolant and engine oil into an engine, starting the engine, and carrying out the running-in of the engine; s2, after engine running-in is completed, testing cooling liquid and testing engine oil are injected into the engine after running-in, the engine is started, and cooling liquid running-in is conducted; s3, after cooling liquid running-in is completed, cooling liquid circulation is conducted; s4, after circulation of the cooling liquid is completed, a cylinder sleeve of the engine is disassembled; and S5, counting the number of the corrosion spots on the engine cylinder sleeve, and judging whether the test cooling liquid is qualified or not according to the counting result of the number of the corrosion spots. According to the invention, the vacancy of an engine pedestal detection method for cavitation corrosion of inorganic and organic engine coolant products at present is filled up, and an earlier-stage research foundation is laid for subsequent improvement of the standard technical level of the engine coolant products.

The invention discloses equipment and a method for testing a material under the coupling action of erosion, cavitation erosion and corrosion. The equipment comprises a grinding fluid circulating unit, an ultrasonic generation unit, a multi-angle erosion generation unit and a reaction unit, based on the equipment, the abrasive type, concentration and pH value of abrasive liquid are adjusted according to corrosion and erosion test requirements, whether a circulating cooler is started or not is selected according to set reaction liquid temperature requirements, and when the circulating cooler needs to be started, the temperature is set for cooling; setting the amplitude and frequency of the ultrasonic controller according to cavitation erosion test requirements, and setting test duration; the control valve is used for adjusting the rotating speed of the grinding liquid pump according to the erosion test requirement, adjusting the jet velocity and regulating the nozzle with the required jet angle; the sample can be subjected to one or more coupling tests of cavitation erosion, erosion and corrosion. Compared with an existing scheme, the method is more practical, the cavitation erosion process of the material under the actual working condition can be better reflected, and a guarantee is provided for deeper development of hydraulic material test research.

The invention relates to the technical field of water pump engineering, and provides a water pump blade cavitation erosion area shape and material loss amount calculation method under a sand carrying condition, and the method comprises the following specific steps: determining characteristic parameters, carrying out transient numerical simulation on a research object to determine a cavitation area, and obtaining related flow field parameters; introducing a flow velocity correction factor and a sediment carrying correction factor to respectively reflect the influence of the water flow velocity and sediment particles on the loss amount of the cavitation erosion material; the cavitation erosion offset distance is calculated, and the shape of the cavitation erosion area is determined according to the cavitation erosion offset distance and the geometric contour of the cavitation area; and calculating the material loss amount of the cavitation erosion area by using the flow velocity correction factor and the sand carrying correction factor. Aiming at a given water pump, the cavitation erosion area shape and the material loss amount of the blade of the water pump under different sand carrying working conditions can be quickly and accurately predicted, the problem that the cavitation erosion area shape and the material loss amount of the blade of the water pump under the sand carrying condition are difficult to accurately predict by an existing method is solved, and effective guarantee is provided for cavitation erosion protection of the water pump under the sand carrying condition.

A temperature-control low-pressure beaker for a vibration cavitation erosion test is characterized in that a beaker body is a double-layer beaker body composed of an inner-layer beaker body and an outer-layer beaker body, a cavity is formed between the inner-layer beaker body and the outer-layer beaker body, and a main control board, an operation panel and an electric heating coil are arranged in the cavity at the bottom of the beaker body, an electric connector connected with the operation panel is further arranged, two or more semiconductor refrigeration chips are symmetrically arranged in a cavity located in the side wall of the cup body, a magnetostriction instrument amplitude-change pole penetrates through the center of the cup cover, and the end of the magnetostriction instrument amplitude-change pole is connected with a tested test piece located in the cup body. An exhaust mechanism communicated with the interior of the cup body is arranged on the side wall of the cup body. The test device capable of autonomously controlling air pressure and intelligently controlling temperature is designed on the basis of original test requirements, can be used for simulating a low-air-pressure environment at a high altitude, and is convenient for researching a cavitation mechanism at low air pressure by using a vibration cavitation test.

The invention belongs to the technical field of anti-freezing solutions, particularly relates to an anti-freezing cooling liquid and a preparation method and application thereof, and provides an all-organic heat transfer system anti-freezing cooling liquid which contains efficient all-organic adsorption acid and an anti-corrosion inhibition additive, has better anti-corrosion and anti-rust capabilities on various metals, and has a good anti-freezing effect. And the anti-corrosion agent has excellent anti-rust function for soldering tin, cast aluminum, cast iron, steel, brass, red copper and the like, especially the anti-corrosion performance of a wet cylinder sleeve of a heavy-duty vehicle. The lubricating oil has excellent cavitation erosion resistance and pitting corrosion resistance, and has an excellent protection effect on an engine cooling system. The anti-freezing cooling liquid product is free of precipitates, stable in performance, safe, non-toxic, green and environment-friendly.

The invention belongs to the technical field of seawater desalination, and particularly relates to a pressure exchanger and a water treatment system.The pressure exchanger comprises a sleeve part, a rotor and an end cover assembly, a communicating structure is formed between a first end cover and the rotor, and / or a communicating structure is formed between a second end cover and the rotor, and the communicating structures are used for communicating with the first end cover and the second end cover when the rotor rotates. The adjacent input channels and output channels on the corresponding end covers are communicated, so that the transmission of pressure in the overflowing channels of the rotor forms a gradient between corresponding ports of the input channels and the output channels of the end cover assembly; in the rotating process of the rotor, liquid carried in the overflowing channel and pressure energy of the overflowing channel can be gradually released or loaded in the rotating process, pressure sudden change is avoided, cavitation erosion caused by the pressure sudden change can be eliminated, the pressure transmission time is prolonged, and vibration and noise are reduced.

A low-temperature pipeline cavitation and cavitation erosion experiment table disclosed by the present invention comprises a liquid supply tank, a venturi tube assembly and a receiving tank, the venturi tube assembly comprises a venturi tube, a test piece mounting seat and a plurality of sensors, one end of the venturi tube assembly is communicated with the liquid supply tank, the other end of the venturi tube assembly is communicated with the receiving tank, and the cross section of a flow channel of the venturi tube is rectangular. An embedding groove and a plurality of sensor mounting grooves are formed in the flow channel wall of the venturi tube; the test-piece mounting seat is used for fixing a test-piece; the plurality of sensors comprise a vibration sensor, a temperature sensor and a pressure sensor, and the vibration sensor is arranged on the test piece mounting seat; the temperature sensor and the pressure sensor are respectively embedded in the corresponding sensor mounting grooves; by adopting the design of the venturi tube with the rectangular section, the space adaptability and the experiment controllability are remarkably improved. The test piece and various sensors are arranged along the venturi tube, so that the accurate association between the material cavitation damage and the multi-physical field signal is realized, the cavitation collapse transient process is accurately captured, and the reliability of experimental data is guaranteed.

The present invention discloses a long-lasting anti-corrosion multilayer coating on the surface of a turbine blade and a preparation method thereof, specifically comprising: preparing powder particles for spraying, preparing an anti-erosion coating and a composite anti-cavitation coating by HVOF, and alternately spraying to obtain the long-lasting anti-corrosion multilayer coating; the multilayer coating is composed of an anti-erosion coating and an anti-cavitation coating alternately sprayed on a blade substrate, and the anti-cavitation coating and the anti-erosion coating are alternately exposed and have appropriate layer thicknesses to specifically resist cavitation damage in non-flood seasons and erosion damage in flood seasons, reduce the overall abrasion rate of the coating, and extend the service life of the blade. At the same time, the service life of the blade is regulated by changing the number of layers of the anti-erosion coating and the anti-cavitation coating, which is also helpful to predict the overhaul cycle of the turbine and reduce the exploration workload. It has important application prospects in the field of surface protection of hydraulic machinery.

A valve member (25, 125) for a fuel injector control valve comprising a unitary metal body with a threaded bore therethrough concentric with a cylindrical outer surface (42); wherein the cylindrical outer surface (42) has a composite ring (26); wherein a portion of the composite ring (26) is defined by an annular valve surface (43); wherein the composite ring (26) is located in a small diameter segment (46) of the cylindrical outer surface (42); wherein an additional ring is defined by a large diameter segment (47) of the cylindrical outer surface (42); wherein the composite ring (26) has a small ring (45) which opens into a large ring (44); wherein a center of the small ring (45) is offset with respect to a center of the large ring (44); and wherein the small ring (45) has a U-shaped cross-section.

The utility model discloses an integrated type swing cycle pump lubricating device, including pump casing, inner rotor and outer rotor, be provided with oil cavity and with oil inlet and oil outlet of oil cavity communication on the pump casing, its characterized in that, the bottom of oil cavity is provided with annular unloading groove with oil outlet communication, and the bottom surface of annular unloading groove is multistage step surface. This integrated type swing cycle pump lubricating device can effectively buffer fluid resistance and pulsation, reduce cavitation and cavitation erosion phenomenon, and stabilize oil pressure of oil outlet.

The invention discloses a structural design method and device for engine connecting rod bearing lubricating oil film cavitation erosion inhibition, and the method comprises the steps: 1, selecting a connecting rod bearing of a diesel engine as an object, building a geometric model of a lubricating oil film between bearings, introducing the built geometric model into a pre-built external flow field, and obtaining a corresponding flow field physical model; 2, simulating the flow field physical model by adopting a numerical simulation method to obtain gas phase volume fraction and oil film pressure distribution data; 3, the bearing bush grooving method of the diesel engine is changed, and the step 1 and the step 2 are repeated; 4, analyzing the engine connecting rod bearing lubricating oil film cavitation simulation result to obtain the change rule of the cavitation degree under different bearing bush grooving methods; and 5, a bearing bush slotting method for the selected diesel engine connecting rod bearing is established. According to the method, the optimal bearing bush slotting mode is compared and selected through a numerical simulation method to achieve the purpose of engine connecting rod bearing lubricating oil film cavitation erosion inhibition.

The invention belongs to the technical field of material performance evaluation, and provides a metal material cavitation erosion incubation period prediction method based on surface plastic deformation analysis. The method comprises the following steps: carrying out cavitation erosion test on a sample; measuring the surface profile length of the sample in the cavitation environment, and calculating the surface area increment rate of the sample; drawing a surface area increment rate-time change curve, and obtaining an incubation period demarcation point and an incubation period end point of the sample; predicting the incubation period of the actual equipment according to the incubation period demarcation point and the incubation period end point; by analyzing the surface area increment rate of the material exposed in the cavitation environment, the incubation period is divided into two stages dominated by hardness and strain hardening indexes, a quantitative relation with the material performance is established, and non-destructive life prediction is achieved.

The application discloses a novel anti-cavitation surface structure and a preparation method thereof. The anti-cavitation surface structure can change the wetting degree of a material surface, reduce gas nuclei near a liquid-solid contact surface, inhibit cavitation and cavitation erosion processes, and also reduce the damage of micro-jets to the material in the cavitation erosion process. The anti-cavitation surface structure layer is composed of a surface construction layer and a substrate. The working mechanism is as follows: firstly, the construction can change the wetting degree of the material surface, so that the gas nuclei near the liquid-solid contact surface are reduced, thereby slowing down the cavitation and cavitation erosion processes; secondly, the incident kinetic energy of the micro-jets in the effective construction area is consumed in the form of friction, thereby reducing the damage of the micro-jets to the material substrate. The application can effectively slow down the cavitation erosion process, weaken the influence of the micro-jets on the material substrate in the cavitation erosion process, and effectively resist the damage of the cavitation erosion to the material surface.

The invention discloses a cavitation and cavitation erosion integrated generation device for a hydraulic element. The cavitation and cavitation erosion integrated generation device comprises a core observation test block and a replaceable cavitation core part, the core observation test block is of a cuboid structure made of a transparent material; a functional oil duct, a low-pressure oil duct, a high-pressure oil duct and a sensor oil duct are arranged in the core observation test block; a piston cylinder and a piece-containing anti-rotation piston are symmetrically arranged on the left side and the right side of the core observation test block; the part-containing anti-rotation piston is mounted in the piston cylinder in a sealing manner; the replaceable cavitation core part is made of transparent materials, one end of the replaceable cavitation core part is fixedly connected with the part-containing anti-rotation piston, and the other end of the replaceable cavitation core part extends into the functional oil duct. And a cavitation channel for communicating the high-pressure oil channel with the low-pressure oil channel is formed between the two replaceable cavitation core pieces. The device is high in replaceability or interchangeability, controllable in pressure flow and controllable in structure position, and can integrally meet the requirements of visual cavitation and cavitation erosion generation.

The invention discloses a sluice channel system for danger elimination of a barrier lake and a working method of the sluice channel system, and relates to the field of emergency disposal of barrier lakes. The sluice channel system comprises a sluice channel structure, an anti-scour layer and a monitoring system, the anti-scour layer comprises a plurality of air bag cushion units, and the air bag cushion units are laid on the sluice channel structure; the monitoring system comprises a flow velocity sensor and a control unit. By integrating the sluice groove structure, the anti-scouring layer and the monitoring system, dynamic regulation and control of the sluice groove scouring process can be achieved. When the flow velocity sensor detects that the water flow reaches a preset scouring critical value, the control unit starts the air bag cushion unit to sink to form a continuous anti-scouring covering layer so as to inhibit impact erosion of the water flow to the tank bottom, the anti-scouring covering layer is utilized to reduce damage of high-speed water flow phenomena such as cavitation erosion and pulsating pressure to the tank body, and the stability of the tank bottom is improved.

The present invention discloses a method and device for predicting cavitation erosion in a gas phase condensation process, and an electronic device, comprising: calculating the potential power in each unit based on the energy generated when the cavitation bubble collapses; dividing the potential power in each unit by the unit volume to obtain the potential power density; simplifying the potential power density; calculating the gas phase condensation rate; constructing a modified cavitation prediction calculation model based on the simplified potential power density and the gas phase condensation rate, wherein the gas phase condensation rate is less than zero; establishing a three-dimensional hydrofoil model and sequentially performing flow channel extraction and calculation domain processing to obtain a three-dimensional fluid calculation domain model; meshing the three-dimensional fluid calculation domain model to obtain a grid model; performing fluid simulation calculation on the grid model to obtain calculation data; based on the calculation data, using the modified cavitation prediction calculation model to calculate and obtain a cavitation erosion cloud map; and obtaining a cavitation erosion prediction result based on the cavitation erosion cloud map.

This application discloses an intelligent detection method and system for corrosion defects in flood discharge tunnels, relating to the field of tunnel corrosion detection technology. The method includes: generating a cavitation number distribution cloud map of the entire flood discharge tunnel area based on historical operating data; marking areas with cavitation values ​​below a preset cavitation number threshold as theoretical high-risk areas; marking areas with cavitation noise intensity exceeding a preset noise threshold as measured noise active areas; spatially superimposing and comparing the theoretical high-risk areas and the measured noise active areas to determine cavitation confirmation areas, potential cavitation risk areas, and cavitation anomaly areas; outputting a surface damage index through a pre-trained cavitation damage assessment model; calculating a dynamic cavitation risk factor; and generating a structured corrosion defect detection report. This method solves the problems of low detection efficiency, limited detection range, and difficulty in accurately assessing corrosion risk in existing flood discharge tunnel corrosion detection methods.

The application provides a water turbine flat pressure pipe cavitation erosion suppression structure based on pressure propagation timing control, which comprises a pipeline installation base and a flat pressure pipe inlet structure. The flat pressure pipe inlet structure is provided with a bottom plate part and a pipe body. A plurality of first through holes are arranged on the outer side of the pipe body along the circumference of the bottom plate part. A plurality of second through holes are arranged on the outer side of the first through holes along the circumference. A plurality of third connection interfaces are arranged on the pipe body along the length and the circumference. The pipeline installation base comprises a sleeve part. A flange part is arranged at one end of the sleeve part. The sleeve part is sleeved on the outer side of the pipe body. The sleeve part is provided with a plurality of third connection interfaces aligned with the third through holes. The flange part is provided with a plurality of first connection interfaces and second connection interfaces aligned with the first through holes and the second through holes. A pressure wave conducting pipe is communicated at each second connection interface. The other end of the pressure wave conducting pipe is closed. A plurality of communication openings are arranged on the pressure wave conducting pipe along the length direction. A plurality of timing adjustment pipes are further arranged. One end of each timing adjustment pipe is communicated with the third connection interface. The other end of each timing adjustment pipe is communicated with the first connection interface or the communication opening.

According to the hydroelectric generating device capable of directly driving the generator to do work through potential energy change, the mode of a conventional water turbine power generation system is thoroughly changed, a water turbine is not needed, the hydroelectric generating device capable of directly driving the generator to do work through potential energy change is achieved, the rectangular barrel can be filled with water, and therefore a high-pressure water supporting bucket water column is formed; potential energy change of the water column can drive the generator to do work; only potential energy changes in the whole operation process, so that the power generation process is low in noise and free of waterfall, and the problem of underwater replacement of the water turbine due to abrasion and cavitation erosion is solved; the bottom of the dam does not need to be provided with holes, so that the dam is high in strength, and about 20% of reinforced concrete can be saved; as the rectangular barrel and the water supporting bucket directly reach the bottom of the dam, energy is utilized completely, and the utilization rate or the generating capacity is about 33% higher than that of a conventional water turbine; a stator of the generator adopts copper-clad iron enameled wires, and coils are arranged in a crossed manner and are mutually laminated, so that the copper-clad iron coils in the generator not only can generate a magnetic field, but also can play a role in enhancing the magnetic field intensity like an iron core.