68 results about "Cavitation flow" 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 underwater cleaning robot for the net cage and the netting comprises a robot central frame, a thrust propeller, a side thrust propeller, crawler wheels, an underwater camera, a tensioning wheel and a water jet cleaning mechanism, the water jet cleaning mechanism comprises a cleaning disc, an adjuster machine body, a water inlet pipe, a water spraying pipe and a petal-shaped cavitation spray head, and the underwater camera collects netting shaking data; after compensation thrust is calculated through feedback, a thrust propeller provides compensation force to counteract shaking of the netting, a tensioning wheel can tension the netting, the robot can be more effectively attached to the net face, in the walking process of the robot, an external high-pressure pump can pump high-pressure water into a regulator machine body through a water inlet pipe, and therefore the net face can be more effectively attached to the net face. The jet flow is sprayed out through the water spraying pipe and the petal-shaped cavitation nozzles to clean the netting, the petal-shaped cavitation nozzles on the two sides incline towards different sides, the sprayed petal-shaped cavitation fluid can drive the regulator body to rotate, rotary cleaning is achieved, and the cleaning area range and cleanliness of the jet flow are 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 invention discloses a cavitation multiphase flow detection experiment system in the field of fluid testing, and the system comprises a liquid circulation pipeline module which comprises an inflow section, a gas-liquid mixing section, a testing section and a backflow section, and is used for forming a liquid flowing loop, and achieving the functions of inflow condition controllability and outflow state recovery of a main flow; the gas inlet and gas-liquid mixing pipeline module is communicated with the gas-liquid mixing section and is used for forming a gas-liquid two-phase fluid medium and realizing the controllability of the gas-phase medium; the cavitation flow experiment module is arranged corresponding to the test section and is used for forming a cavitation flow phenomenon and realizing a cavitation flow visualization function; and the multiphase flow test module is arranged corresponding to the cavitation flow experiment module and is used for detecting the characteristics of the cavitation multiphase flow field and realizing a non-intrusive test function. The gas-liquid two-phase flow state can be controlled, two-phase flow media under different gas-containing conditions can be obtained, cavitation flow states of different degrees can be formed, and cavitation flow characteristics under gas-containing influence can be analyzed conveniently.

The invention relates to the technical field of cleaning equipment, in particular to an underwater cavitation jet observation experiment device and method based on a triangular reflector, and the device comprises a jet control device, an impact observation device, a plurality of light source assemblies and a high-speed camera. The spraying control device comprises a nozzle, and external high-pressure water flow is sprayed out downwards from the nozzle after passing through the pump pipe; the impact observation device comprises a clamping device. The clamping device comprises a triangular prism reflector and a support used for placing the triangular prism reflector. A shot picture of the high-speed camera can simultaneously comprise a free jet flow area and a jet flow impact area reflected by the triangular prism reflector. According to the double-angle free cavitation jet flow observation device, the three-edged reflector is utilized, cavitation flow evolution of a free jet flow area of cavitation jet flow and a jet flow impact area reflected by the three-edged reflector can be observed at the same time, and double-angle free cavitation jet flow observation is achieved.

The invention discloses a low-temperature fluid cavitation flow field cloud picture construction method and device considering interfacial tension. The method comprises the following steps: establishing a Venturi tube model and carrying out grid division; based on the thermodynamic effect in the low-temperature cavitation process, a cavitation model in Fluent simulation software is corrected; a surface tension coefficient of interphase acting force in a multiphase flow model in Fluent simulation software is changed to be customized by a user, a low-temperature medium surface tension function changing along with temperature is written into the Fluent simulation software in a UDF file form, a surface tension model of continuous surface force is opened, wall adhesion is checked, and a contact angle is added; importing the Venturi tube model subjected to grid division into Fluent simulation software for numerical simulation; and performing imaging processing on a result obtained by numerical simulation to obtain a cavitation flow field cloud picture. The rationality of the method is judged by comparing the cloud picture of the cavitation flow field with an experimental result.

An underwater cleaning robot for the net of a cage, comprising a central robot frame, a thrust propeller, side thrust propellers, crawler wheels, an underwater camera, a tensioning wheel and a water jet cleaning mechanism. The water jet cleaning mechanism includes a cleaning disc, a regulator body, a water inlet pipe, a water spray pipe and a petal-shaped cavitation nozzle. The underwater camera collects the net shaking data, and after calculating the compensation thrust through feedback, the thrust propeller provides a compensation force to offset the net shaking. The tensioning wheel can tension the net, making the robot fit the net surface more effectively. During the walking process of the robot, an external high-pressure pump can pump high-pressure water into the regulator body through the water inlet pipe, and spray it out through the water spray pipe and the petal-shaped cavitation nozzle to achieve the cleaning of the net. The petal-shaped cavitation nozzles on both sides are inclined to different sides, and the petal-shaped cavitation fluid ejected can drive the regulator body to rotate, realizing rotary cleaning and improving the cleaning area range and cleanliness of the jet.

According to the BDIM-based propeller cavitation streaming simulation algorithm provided by the invention, the particularity of a propeller structure is considered, a hyperbolic tangent encryption function is introduced into a near-wall region of the propeller structure to carry out non-uniform grid division, and high-gradient flow and boundary layer development of a blade tip region can be effectively captured, so that the resolution of a cavitation source region and a vortex core is improved; in multi-phase interface tracking, a VOF method is adopted to carry out high-resolution reconstruction on fluctuation behaviors of a vapor-liquid interface, interface diffusion distortion can be avoided, interface definition and mass conservation can be taken into consideration in combination with double-field evolution of a volume fraction function and an intermediate velocity field, and the method is suitable for being applied to multi-phase interface tracking. The method is particularly suitable for dynamic capture of a cavitation primary area and a complex gas-liquid phase mixing area in a propeller wake, and the precision and reliability of simulation on the cavitation occurrence position, the time scale and the form can be improved.

The present invention relates to a cystoscopy device (100) comprising a tubular main probe (200), a cavitation probe (300), and an image capturing optical unit (400). The main probe (200) sequentially comprises a guide section (210), a separation section (220), an abutment section (230), and an articulated section (240) having a plurality of joint units (241) aligned end to end. The cavitation probe (300) comprises a flexible transmission tube (310) extending along the main probe (200) for transmitting a cavitation fluid to a flow-restricting nozzle (320), and a flow-restricting nozzle (320) positioned at an open end of the articulated section (240) having an inner diameter smaller than the inner diameter of the transmission tube (310) to create cavitation.

The invention provides a cavitation flow field reconstruction method based on sparse perception and an unsupervised learning method, and the method comprises the steps: firstly, carrying out the numerical simulation of cavitation flow around a specific type of hydrofoil, considering the unique characteristics of a cavitation flow velocity field, executing the intrinsic orthogonal decomposition, and representing the intrinsic orthogonal decomposition as a representation form of the superposition of an average velocity field and a pulsation velocity field; a fluid velocity field modal library is constructed on the basis; and then an unsupervised clustering algorithm and sparse data sampling are executed to extract data samples, and fluid velocity field reconstruction is completed by using the velocity field modal library and a small number of data samples. Through verification and comparison of reconstruction effects under different sparse sampling strategies, high-fidelity reconstruction of a complex cavitation flow structure can be finally realized, and compared with the prior art, accuracy and robustness are remarkably improved.

The invention discloses a low-temperature liquid cavitation numerical prediction method considering different-scale heat effects, and belongs to the field of low-temperature liquid cavitation numerical prediction. The implementation method comprises the steps that a corresponding fluid domain geometric model is established, grids are divided, a computational fluid mechanics model is established under the macro-scale, a separation vortex DES turbulence model is adopted, a fluid volume VOF model is used for capturing a macro-scale cavity interface, and convective heat transfer correction under the macro-scale is conducted on a cavitation model; establishing a cavitation kinetic equation considering heat conduction correction under the mesoscale, solving resistance, volume force, additional mass force, pressure gradient force and lift force suffered by the mesoscale discrete cavitation by using a DBM discrete phase model, and obtaining a movement track of the discrete cavitation in a cavitation flow field; and calculating the unsteady cavitation flow by taking a steady result as an initial value to obtain a flow field characteristic under a macroscale and a discrete cavitation dynamic evolution process under a mesoscale, thereby realizing quantitative description and high-precision numerical prediction of the unsteady cavitation flow.

The invention discloses a propeller two-phase flow multi-scale cavitation bubble measurement system based on laser digital holography, and belongs to the field of cavitation flow measurement. The device comprises an experiment section, an experiment model, a supporting rotating shaft, a polarization laser, a concave lens, a first convex lens, a second convex lens, a digital camera, a lens, a dimmer, a synchronous triggering system and a data analysis system. Linear polarization laser is emitted by the polarization laser and is collected by the first convex lens after being expanded by the concave lens, the collected light is collected and collimated by the second convex lens after being collected at the focus of the first convex lens, and parallel light is formed and irradiated to a cavitation area generated by the propeller in the experimental section. Part of the light is diffracted and deviated to form object light when passing through the vacuole, the light which does not pass through the vacuole forms reference light, and alternately dark and bright stripes formed by interference of the object light and parallel light are refracted by the dimmer and the lens and recorded on a digital camera negative film. According to the invention, non-contact measurement of the two-phase flow field of the propeller is realized by using interference recording and diffraction reconstruction.

The application discloses a kind of monitoring devices of pressure fluctuation frequency and amplitude in cavitation collapse process, including water tank, cavitation generator, magnetic fluid, magnetic field device, laser generator, optical splitter, laser probe and receiver;Optical splitter is emitted by single beam laser of laser generator and is divided into two beams, one is emitted as laser, frequency is f ;Another is as reference laser, frequency is f + f r ;Laser probe exports and irradiates on the tip of magnetic fluid by emitting laser, and reflection is formed to form reflected laser, and its frequency is f + f D ;Receiver, accept reflected laser, and it has reference laser inside by optical splitter, and its frequency is f + f r The application can master the whole dynamic data of quantized cavitation collapse by monitoring the frequency and amplitude of whole process pressure fluctuation caused by cavitation collapse in liquid environment through magnetic fluid magneto-rheological effect, tip surface effect and Doppler effect, which provides important technical means for single-cavity theory development and hydraulic machinery cavitation flow research.

The invention discloses a cavitation model correction method considering a transient effect of a flow field. The method comprises the steps that a Rayleigh-Plesset equation is used for simulating the change of the cavitation radius, and magnitude analysis is carried out based on cavitation influence factors to obtain a nonlinear bubble motion equation; and integrating the nonlinear bubble motion equation to obtain a bubble wall velocity model considering the flow field transient effect, obtaining a mass transfer rate function considering the flow field transient effect by using the bubble wall velocity model, and finally correcting the mass transfer rate of the original cavitation model based on the mass transfer rate function considering the flow field transient effect to realize the correction of the cavitation model. According to the corrected cavitation model provided by the invention, the influence of the fluid transient effect on the cavitation flow is fully considered, the phase change simulation precision is improved, the cavitation flow field obtained by calculation is more in line with the physical reality, and the method provides a new thought for transient change calculation in the cavitation flow.

The embodiment of the invention provides a drag reduction effect AI control method and system for a natural-ventilation mixed cavitation hydrofoil, and relates to the technical field of ship engineering. Executing a cavitation flow experiment to obtain an input data set and an output data set; performing feature extraction based on the input data set and the output data set to obtain a cavitation coverage area rate, a flow field instability feature parameter, an interface evolution stability index and a signal cavitation index, and integrating into a response data set; constructing a comprehensive data source set based on the input data set, the output data set and the response data set; and determining the influence level of the current ventilation behavior based on the response data set, and determining an optimal design scheme based on the influence level and the comprehensive data source set. The method overcomes the limitation that a traditional static black box model only depends on an input-output relation and lacks process feedback, and effectively distinguishes operation states which are temporarily low in resistance but about to be unstable from operation states which are really stable and efficient.

A valve assembly includes a housing which has a liquid inlet and a liquid outlet, a cover affixed to the housing, a flow regulating assembly located in the housing, and an anti-cavitation flow diverter mounted in the housing. The anti-cavitation flow diverter includes an outer wall that surrounds an inner hollow portion. Sets of flow apertures are formed through the wall thickness of the outer wall. Each flow aperture is open to the inner hollow portion and extends at an angle along a non-radial path through the outer wall. Flows of liquid flowing through each set of the flow apertures impinge upon each other at meeting points which are spaced from inner surfaces of the housing.

The utility model relates to the technical field of oral care, in particular to a nozzle and a water pick. The nozzle includes a body. The interior of the main body is hollow to form a flow channel, and the flow channel comprises an inflow port allowing flushing fluid to flow in and an outflow port spraying the flushing fluid. Any position in the inlet flow section can be cut by a preset plane to form a first section, any position in the outlet flow section can be cut by the preset plane to form a second section, and any position in the cavitation flow section can be cut by the preset plane to form a third section. The size of the first section and the size of the second section are both larger than that of the third section. At least one part of the cavitation flow section has the same size on the third cross section corresponding to each position in the direction vertical to the flowing direction of the flushing fluid. According to the nozzle, by arranging the cavitation flow section with the small cross section area, flushing fluid is subjected to cavitation, bubbles generated by cavitation are mixed through the outlet flow section, the pressure of the flushing fluid is reduced, and the cleaning effect is improved.

The invention relates to the technical field of state monitoring and fault diagnosis of ship power devices, and provides a noise data processing method based on cavitation flow characteristics of a propeller. According to the method, observable dynamic frequencies such as leaf frequency and cavitation bubble falling main frequency and statistical non-stationary quantities such as a frequency spectrum broadening factor, self-correlation time, broadband energy and kurtosis are unified in the same analysis framework, a mapping model of a cavitation state and signal processing parameters is constructed, analysis parameters such as FFT, STFT and CWT are adaptively configured, and the analysis parameters of the cavitation state and the signal processing parameters are analyzed. And multi-scale feature extraction of non-stationary pressure pulsation signals under different cavitation types and cavitation intensities is realized. According to the method, the cavitation state and type are identified and evaluated on the basis of the extracted multi-domain features, the threshold and mapping parameters are reversely updated according to the identification result, a closed loop of state judgment, parameter mapping, multi-domain analysis, feature output, cavitation identification and parameter updating is formed, and the precision and engineering applicability of propeller cavitation monitoring and diagnosis are improved.

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.

A valve assembly includes a housing which has a liquid inlet and a liquid outlet, a cover affixed to the housing, a flow regulating assembly located in the housing, and an anti-cavitation flow diverter mounted in the housing. The anti-cavitation flow diverter includes an outer wall that surrounds an inner hollow portion. Sets of flow apertures are formed through the wall thickness of the outer wall. Each flow aperture is open to the inner hollow portion and extends at an angle along a non-radial path through the outer wall. Flows of liquid flowing through each set of the flow apertures impinge upon each other at meeting points which are spaced from inner surfaces of the housing.

The invention relates to a multi-phase flow closed-loop regulation and control experiment system for ventilation cavitation bubbles around a revolving body of a vertical water tunnel, and belongs to the field of cavitation water tunnel experiment technologies and equipment. Comprising a control system, a sensing system, a ventilation system, a rudder deflection system and an experimental model. The sensing system senses the state of the experimental model in real time; the control system is used for generating a rudder deflection control instruction and sending the rudder deflection control instruction to the rudder deflection system; a ventilation control instruction is generated and sent to a ventilation system; the rudder deflection system is used for adjusting rudder deflection parameters of the experimental model according to the rudder deflection control instruction, so that the attitude of the experimental model is adjusted, and the free pitching motion of the experimental model is realized; the ventilation system is used for adjusting ventilation parameters of the experimental model according to the ventilation control instruction so as to adjust the cavitation flow capacity of the experimental model; according to the invention, an experimental platform and a research basis are provided for research on flow phenomena such as cavitation falling and collapse and related large-scale and strongly-uncertain hydrodynamic characteristics under the flow direction gravity condition.

An acoustic energy tool comprising a crystal for generating acoustic energy when a volage is applied to the crystal, and a resonator. The resonator has a solid outer structure with the crystal being attached to the solid outer structure, with the resonator being comprised of a material that transmits the acoustic energy through the resonator. The tool includes a curved surface that focuses the acoustic energy being transmitted through the resonator and a fluid passageway that extends through the resonator for allowing a fluid to flow through the resonator. The acoustic energy being focused by the curved surface is concentrated in the fluid passageway so that it causes cavitation of the fluid in at least part of the fluid passageway. The cavitation of the fluid is used to break up clumps that form in the fluid or to generate reactive oxygen species.

This invention relates to the field of submerged cavitation water jets, specifically to a method for simulating the flow field load and ice-breaking of submerged water jets considering cavitation effects. The method includes obtaining an initial flow field-ice plate topology model; adjusting the fractal dimension of the mesh through a fractal growth mechanism, fusing a probabilistic model, and embedding a viscoelastic network stress transfer mechanism to obtain a fractal characteristic load field; converting the load generated by fractal iterative loading into the stress and strain of the ice plate, extracting dynamic damage evolution data of the ice plate and chaotic characteristic parameters from the fractal characteristic load field, and obtaining optimized submerged water jet parameters. This invention constructs coupling and correlation rules, clarifying the core coupling relationship between the cavitation-sensitive region and the ice plate load action region, ensuring that the cavitation load is accurately transferred to key areas of the ice layer. By adjusting the fractal dimension of the mesh in real time through a fractal growth mechanism to adapt to the dynamic evolution stage of cavitation bubbles, it solves the problem that traditional models cannot simultaneously capture the cavitation flow field morphology and ice plate damage.

The application discloses a structure optimization method for inhibiting cavitation of a low-temperature stop valve, and comprises the following steps: S1, establishing a stop valve model and performing grid division; S2, performing a numerical calculation on the stop valve model after the grid division, obtaining a cavitation flow field cloud picture based on the calculation result, and determining a key position of cavitation occurrence; S3, optimizing the stop valve model, that is, setting a uniform grid-shaped flow guide plate at the key position of cavitation occurrence; S4, performing a second numerical calculation on the optimized stop valve model, obtaining an average gas phase volume and a flow coefficient based on the calculation result; S5, performing optimization judgment according to the average gas phase volume and the flow coefficient; and S6, repeating S4 and S5 until the average gas phase volume and the flow coefficient both meet the requirements, and outputting structure parameters of the optimized stop valve. The method can be widely applied to the design and optimization of stop valves in a low-temperature fluid conveying system, and has remarkable engineering application value.

An acoustic energy tool comprising a crystal for generating acoustic energy when a volage is applied to the crystal, and a resonator. The resonator has a solid outer structure with the crystal being attached to the solid outer structure, with the resonator being comprised of a material that transmits the acoustic energy through the resonator. The tool includes a curved surface that focuses the acoustic energy being transmitted through the resonator and a fluid passageway that extends through the resonator for allowing a fluid to flow through the resonator. The acoustic energy being focused by the curved surface is concentrated in the fluid passageway so that it causes cavitation of the fluid in at least part of the fluid passageway. The cavitation of the fluid is used to break up clumps that form in the fluid or to generate reactive oxygen species.

The utility model discloses a cavitation multiphase flow detection experiment system in the field of fluid testing, which comprises a liquid circulation pipeline module which comprises an inflow section, a gas-liquid mixing section, a testing section and a backflow section and is used for forming a liquid flowing loop and realizing the functions of controllable inflow conditions and outflow state recovery of main flow; the gas inlet and gas-liquid mixing pipeline module is communicated with the gas-liquid mixing section and is used for forming a gas-liquid two-phase fluid medium and realizing the controllability of the gas-phase medium; the cavitation flow experiment module is arranged corresponding to the test section and is used for forming a cavitation flow phenomenon and realizing a cavitation flow visualization function; and the multiphase flow test module is arranged corresponding to the cavitation flow experiment module and is used for detecting the characteristics of the cavitation multiphase flow field and realizing a non-intrusive test function. The gas-liquid two-phase flow state can be controlled, two-phase flow media under different gas-containing conditions can be obtained, cavitation flow states of different degrees can be formed, and cavitation flow characteristics under the influence of gas can be analyzed conveniently.

The present invention discloses an apparatus and method for efficiently removing chlorides from municipal solid waste incineration fly ash through hydrodynamic cavitation. The apparatus includes a fly ash silo, a stirring tank, a peristaltic pump, two cavitation tubes, a water storage tank, a filter press, and a wastewater recycling component. The method comprises the following steps: S1, preparation of fly ash slurry; S2, fitting of hydrodynamic cavitation parameters; S3, staged hydrodynamic cavitation: S3-1, determination of the optimal mass concentration; S3-2, determination of the optimal cavitation flow velocity; S4, continuous hydrodynamic cavitation; S5, post-treatment. Through hydrodynamic cavitation, the present invention can effectively promote the dissolution of soluble chlorides, greatly improve the removal rate of soluble chlorides, further reduce industrial water consumption, and the recycled water can be recycled, with low cost and good chloride removal effect. No chemical agents are used in the process of fly ash dechlorination, and environmental protection and efficient impurity removal of incineration fly ash can be achieved.

The invention relates to a cavitation erosion prediction method considering cavity collapse and an energy transport process thereof, and belongs to the technical field of hydrodynamic research. The cavitation prediction method comprises the following steps: solving a cavitation flow field for a to-be-predicted object; based on the physical characteristic change of cavity collapse, recognizing a collapse area and recording cavity collapse pressure; collapse energy is calculated according to the cavity collapse pressure; analyzing the transportation process of collapse energy radiation to the to-be-predicted position of the wall surface, calculating a transfer parameter and an attenuation parameter, and multiplying the transfer parameter and the attenuation parameter to obtain a transportation parameter; calculating the cavitation erosion load radiated to the wall surface by the collapse energy in combination with the collapse energy and the transportation parameters, and accumulating to obtain the accumulated cavitation erosion load of the current prediction position of the wall surface; and determining a cavitation erosion area according to the accumulated cavitation erosion load. According to the cavitation prediction method, the real physical process of cavity collapse is considered, the authenticity of collapse area identification is ensured, meanwhile, the transfer and dissipation processes in energy transportation are considered, and the accuracy of cavitation area prediction is ensured.

The present invention discloses a numerical prediction method for internal reflow and reflow vortex cavitation of a vane pump, which is used to predict the internal reflow and reflow vortex cavitation phenomenon of a vane pump under low flow conditions. The method comprises: step 1) numerically calculating the steady flow inside the pump and the cavitation flow inside the pump under different working conditions in CFD software, extracting flow field information, and obtaining impeller cavitation distribution. Step 2) based on the numerical calculation results of step 1), numerically calculating the unsteady flow inside the pump, and setting relevant pressure pulsation monitoring points. Performing unsteady numerical simulation on typical working points, extracting flow field and pressure pulsation information. Step 3) based on step 2), comparing the main frequency of each monitoring point, and performing phase correlation analysis on the pressure pulsation signal, obtaining the number of unstable flow units and the corresponding axial and radial characteristics. Based on the flow field information of steps 1) and 2), comparing and analyzing the critical working points where reflow and reflow vortex cavitation occur.

The present application belongs to the technical field of intersection of computational fluid dynamics and artificial intelligence, and in particular to a high-precision prediction method for a hydrodynamic torque converter cavitation flow field. The method comprises the following steps: S1: obtaining transient CFD flow field simulation data inside the guide wheel flow passage of the hydrodynamic torque converter; S2: constructing a multi-task neural network model; S3: constructing a hybrid supervised loss function for optimizing the cavitation prediction sub-network; S4: training the neural network model by adopting a three-stage decoupling strategy; S5: constructing a physical residual loss term based on the law of conservation of fluid dynamics; and S6: inputting the space-time coordinates to be predicted into the trained neural network model. The present application improves the recognition accuracy of sparse cavitation features, enhances the training stability of complex multiphase flow fields, improves the physical consistency of the prediction results, and significantly improves the calculation efficiency of the cavitation flow field.