132 results about "Cavitation erosion" patented technology

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 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 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.

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.

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.

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.

The invention provides an engine control method and device for preventing cavitation erosion of an air cylinder sleeve, a medium and a product, and relates to the technical field of engine control, and the method comprises the steps that the cooling water pressure value of a data collection point close to one side of the air cylinder sleeve in a cooling water cavity is obtained, the cooling water pressure value of the data acquisition point is in negative correlation with the vibration speed of the cylinder sleeve; whether the cavitation erosion risk exists in the cylinder sleeve is identified based on the cooling water pressure value; if yes, the flow of cooling water flowing through the cooling water cavity is adjusted, so that the pressure value of the cooling water is increased, and adjustment is stopped until the pressure value of the cooling water is larger than the preset saturated vapor pressure of the cooling water; if not, first information used for representing that the cavitation erosion risk does not exist in the cylinder sleeve is sent out. According to the method, the cavitation erosion risk of the cylinder sleeve can be effectively evaluated in real time, corresponding response is quickly made, the method has the remarkable advantages of quick response and high-precision response, the comprehensive durability of the cylinder sleeve can be remarkably improved, and the service life of the cylinder sleeve can be remarkably prolonged.

The utility model discloses an underground drainage filter head, which relates to the technical field of drainage filter heads, and comprises a cylindrical shell, a balancing weight and a buoyancy piece, a joint is arranged at the center of the top of the shell, a plurality of water inlets are uniformly arranged on the side surface of the shell, the balancing weight is arranged at the center of the upper surface of the bottom of the shell, and the buoyancy piece is arranged at the bottom of the shell. The buoyancy piece is arranged on the upper surface of the top of the shell, and the buoyancy of the buoyancy piece, the shell and the balancing weight is smaller than the gravity of the buoyancy piece, the shell and the balancing weight; the buoyancy of the buoyancy piece, the shell and the balancing weight is smaller than the gravity of the buoyancy piece, the shell and the balancing weight, the shell falls to the water bottom after being placed in water, and due to the fact that the top is light and provided with the buoyancy piece, and the bottom is heavy and provided with the balancing weight, the water drainage device can vertically stand in the water and cannot topple over, the water drainage working effect is better, and the cavitation erosion phenomenon can be avoided.

This invention belongs to the field of alloy materials technology and discloses a method for improving the cavitation erosion resistance of Fe-Mn-Al-C lightweight steel. The method involves: pretreating the Fe-Mn-Al-C lightweight steel to remove dust and impurities from its surface, obtaining pretreated Fe-Mn-Al-C lightweight steel; and then subjecting the surface of the pretreated Fe-Mn-Al-C lightweight steel to electron beam remelting under vacuum conditions to form a cladding layer on the surface of the pretreated Fe-Mn-Al-C lightweight steel, thereby improving its cavitation erosion resistance. This invention involves pretreating Fe-Mn-Al-C lightweight steel and then subjecting it to electron beam remelting. The electron beam remelting process alters the surface roughness and structure of the Fe-Mn-Al-C lightweight steel, causing the surface grains to form equiaxed and columnar crystals under the influence of the electron beam. This results in the formation of a dense and more uniform cladding layer on the surface of the Fe-Mn-Al-C lightweight steel, which not only improves the surface hardness and strength of the Fe-Mn-Al-C steel but also enhances its wear resistance, corrosion resistance, and cavitation erosion resistance.

The present invention discloses a butterfly valve disc structure and a butterfly valve for suppressing cavitation, comprising: a body, on which a pressure transmission channel and a jet channel are formed, one end of the pressure transmission channel is a pressure transmission hole, and the other end is connected to the jet channel, one end of the jet channel is a jet inlet, and the other end is a jet outlet; a slider, slidably arranged in the pressure transmission channel; and a spring, one end of which is connected to the slider and the other end is connected to the inner wall surface of the jet channel. When the valve is opened and cavitation occurs, the pressure in the low-pressure area of the butterfly disc drops below the saturated vapor pressure, the slider moves to the left, and the jet channel is opened. The jet channel connects the high-pressure area and the cavitation development area of the butterfly disc. When the jet channel is opened, a jet flow is formed in the cavitation development area, suppressing the development of cavitation and also reducing problems such as cavitation erosion and vibration caused by cavitation.

The application discloses a cutter microstructure processing device and method using valve port fluid cavitation erosion effect. The device comprises a valve body module, a temperature control module, a micro-particle adding assembly and a cutter clamping assembly. The valve body module comprises a valve sleeve and a valve core. The valve core is installed in the inner cavity of the valve sleeve. The inner side wall of the valve sleeve and the outer side surface of the valve core form a cavitation processing flow channel with annular longitudinal section. The cavitation processing flow channel comprises an input flow channel, a throttle port and an output flow channel connected in sequence along the liquid medium flow direction. The temperature control module comprises a temperature sensor and a nested liquid cooling assembly, and the nested liquid cooling assembly comprises a liquid cooling cover sleeved outside the valve body module. The inner side surface of the liquid cooling cover and the outer side surface of the valve sleeve form a heat exchange flow channel. The application utilizes the cavitation effect formed after the fluid medium mixed with micro-particles passes through the throttle port to erode the rake face of the processed cutter, so that the microstructure capable of improving the cutting performance of the processed cutter is rapidly processed on the rake face.

A hydrofoil cavitating flow control structure includes a hydrofoil. A primary protuberant stripe is disposed in a middle position of a suction side of the hydrofoil, a plurality of symmetrically-distributed secondary protuberant stripes are disposed obliquely at both sides of the primary protuberant stripe, and the plurality of secondary protuberant stripes are uniformly and equidistantly distributed along the length direction of the primary protuberant stripe. By changing geometric parameters such as an included angle between the primary protuberant stripe and the second protuberant stripe, a ratio of cross section diameters and a distribution spacing of the second protuberant stripes along a chord length direction of the hydrofoil and the like, the shedding of cloud cavitation on a hydrofoil surface is effectively suppressed, and cavitation erosion and pressure pulsation generated by cavitation collapse is reduced, thus improving the operation efficiency and the service life of hydraulic machinery.

This application relates to a method, apparatus, and computer equipment for rapid determination of cavitation damage in a turbine runner. The method includes: acquiring point cloud data collected by a 3D laser scanner on the surface of the turbine runner; determining the cavitation erosion region based on the geometric features of the point cloud data; determining the cavitation damage area, cavitation damage depth, and cavitation damage volume based on the point cloud data corresponding to the cavitation erosion region; and determining the cavitation damage measurement result of the turbine runner based on the cavitation erosion region, cavitation damage area, cavitation damage depth, and cavitation damage volume. This method leverages the high precision and anti-interference characteristics of the 3D laser scanner to identify cavitation erosion areas using the collected point cloud data, calculate the area, depth, and volume of the cavitation erosion region, and generate accurate cavitation damage measurement results for the turbine runner. This avoids the limitations imposed by the detection environment and operating conditions on cavitation damage detection, achieving efficient cavitation damage detection and thus improving the safety of hydroelectric equipment.

This invention relates to the field of soil slope monitoring technology, specifically to a method for monitoring cavitation erosion in dispersed soil slopes. The method involves acquiring soil moisture, soil temperature, air temperature, air humidity, current rainfall, slope runoff velocity, and images of the soil slope surface and surface water for a target dispersed soil slope. Based on these data, the method determines the rainfall erosion index and soil cavitation sensitivity index for the target dispersed soil slope. Finally, based on these indices, the method determines the risk level of cavitation erosion development for the target dispersed soil slope. This comprehensive and dynamic assessment of cavitation erosion in dispersed soil slopes improves the targeting and timeliness of slope disaster identification and diagnosis, thereby reducing slope disaster risks.

The invention discloses an experimental device and method for simulating single-cavitation erosion in a controllable temperature field, and relates to the field of cavitation dynamics and cavitation erosion. The problem that in the prior art, comprehensive and fine observation and quantitative analysis are carried out on the wall face erosion phenomenon induced by the single cavitation bubble under the controllable temperature condition is solved. The experimental device mainly comprises a heating system used for regulating and controlling the temperature of fluid, a temperature control system, an electric spark discharge device used for generating a single cavitation bubble in the target temperature fluid, a high-speed photography system used for capturing the dynamic behavior of the cavitation bubble, and a microscopic system used for observing and analyzing wall surface damage. The experimental method comprises the following steps: establishing and maintaining a uniform and stable preset target temperature field in a working fluid through a heating and temperature control system, accurately inducing a single cavitation bubble, capturing a dynamic process by using a high-speed photography system, and carrying out quantitative analysis on erosion morphology through a microscopic system. The method is also suitable for the practical engineering application fields of material protection, cavitation effect regulation and control and the like under high-temperature or variable-temperature working conditions.

The application provides a start-stop method of a supercritical carbon dioxide cycle system, and belongs to the technical field of power generation. The method comprises the following steps: the shutdown process of an S-CO2 Brayton cycle power generation system is mainly divided into three stages: the first stage is the process of reducing the system load from 100% to 10%, the load reduction of the system is realized by using valve storage coupling control, and the thermal efficiency of the system is maintained at a high value in a wide load range; the second stage is the process of reducing the system load from 10% to 0, the process is realized by reducing the inlet temperature of the turbine, so that the circulation flow can be ensured not to be reduced during the load reduction process, and the possible pipe explosion accident of the boiler during low load operation can be avoided; the third stage is the process of stopping each device, and the potential over-temperature pipe explosion risk of the gas cooling wall when the working medium flow in the boiler is too low and the cavitation erosion risk of the compressor when the minimum circulation pressure is lower than the critical pressure are considered. The method can ensure the safety and rapidity during the start-stop process of the system.