Cavitation load measurement method

Abstract

This application provides a method for measuring cavitation load, relating to the field of cavitation load measurement. It includes: a container holding liquid; a cavitation load generating unit; the cavitation load generating unit includes a vibrating element; the vibrating element is disposed in the liquid contained in the container to trigger the liquid to generate a cavitation load; a rotating unit; the rotating unit is disposed inside the container, spaced apart from the vibrating element, and includes a rotating element and a support frame for supporting the rotating element, the support frame being fixedly disposed to the container, the axis of the rotating element being perpendicular to the axis of the cavitation load generating unit; the rotating element rotates under the action of the cavitation load, tracer points are marked on the rotating element, and the material of the rotating element is determined based on the material of the hydraulic machinery being measured; and an image acquisition device for acquiring images of the container, the images being used to determine the maximum cavitation load that the hydraulic machinery being measured can withstand. This application can improve the measurement accuracy of cavitation load.

Description

Technical Field

[0001] This invention relates to the field of cavitation load measurement, and more specifically to a method for measuring cavitation load. Background Technology

[0002] Cavitation is a widespread problem in hydraulic machinery. Cavitation refers to the process by which small gas nuclei or dissolved gases in a liquid rapidly expand and coalesce into small bubbles when the pressure drops sufficiently. When these cavitation bubbles (cavitation cavitation bubbles) enter a high-pressure zone, they may collapse due to the rapid increase in pressure, generating strong impact loads. When these impact loads exceed the cohesive force of the material surface, they cause surface damage, leading to cavitation erosion. Cavitation erosion affects the efficiency and service life of hydraulic machinery, resulting in reduced operational performance. Therefore, it is necessary to measure the maximum cavitation load that hydraulic machinery can withstand to ensure that the structure can withstand the expected loads without failure.

[0003] In existing technologies, the measurement of cavitation loads mainly suffers from the following problems:

[0004] 1) The size of cavitation bubbles is generally from a few micrometers to tens of micrometers. Due to limitations in sensor manufacturing processes, current sensors cannot reach the size of cavitation bubbles, resulting in large errors in the measured cavitation load. Therefore, experimental measurement of cavitation load in cavitation erosion is extremely difficult.

[0005] 2) Researchers estimated the cavitation load by measuring the size of the material indentations caused by cavitation load and combining this with the stress-strain relationship obtained from nanoindentation experiments. However, because the indentation size is irregular, the estimation assumed it to be a regular shape, which introduced some error into the calculation results, leading to the calculated load being smaller than the actual cavitation load value. Summary of the Invention

[0006] The purpose of this application is to provide a method for measuring cavitation load, which can accurately measure the maximum cavitation load that hydraulic machinery can withstand.

[0007] In a first aspect, embodiments of this application provide a cavitation load measuring device, the measuring device comprising:

[0008] A container for holding liquids;

[0009] A cavitation load generating unit; the cavitation load generating unit includes a vibrating element; the vibrating element is disposed in the liquid contained in the container, and the cavitation load generating unit is used to trigger the liquid to generate cavitation load;

[0010] Rotating unit; The rotating unit is set inside the container and spaced apart from the vibrating component. The rotating unit includes a rotating component and a support frame for supporting the rotating component. The support frame is fixedly set to the container. The axis of the rotating component is perpendicular to the axis of the cavitation load generating unit. The rotating component rotates under the action of the cavitation load. The rotating component is marked with tracer points. The material of the rotating component is the same as the material of the hydraulic machinery being tested.

[0011] Image acquisition equipment is used to acquire multiple images of a container, including images of rotating parts or cavitation bubbles in the container; it can determine the maximum cavitation load that the rotating parts can withstand based on the multiple images, thereby determining the maximum cavitation load that the hydraulic machinery under test can withstand.

[0012] In some embodiments, the rotating component includes a rotating body and a tracer plate sleeved on the rotating body, with tracer points marked on the tracer plate, and the rotating body is made of the same material as the hydraulic machinery being tested.

[0013] In some implementations, the rotating component and the vibrating component are horizontally offset.

[0014] In some embodiments, the cavitation load generating unit further includes:

[0015] An ultrasonic generator is positioned above the container and on the side of the vibrating component away from the rotating component. The ultrasonic generator is used to generate ultrasonic waves.

[0016] The amplifier, with its two ends connected to the ultrasonic generator and the vibrating element respectively, is used to amplify ultrasonic waves.

[0017] In some implementations, the image acquisition device includes:

[0018] The first image acquisition device is set opposite to the side of the rotating component marked with the tracer point, and is used to acquire images of the tracer point;

[0019] The second image acquisition device is used to acquire images of cavitation bubbles in the container.

[0020] Secondly, embodiments of this application provide a method for measuring cavitation load, applied to the cavitation load measuring device provided in the first aspect, the method comprising:

[0021] The cavitation load measurement device is activated to generate the cavitation load, and multiple images are acquired through the image acquisition device;

[0022] The rotational acceleration of the rotating component is determined based on multiple images acquired by the image acquisition device and the acquisition time of the multiple images;

[0023] The moment of inertia of the rotating component is determined based on its dimensions and mass.

[0024] The cavitation load torque is determined based on the horizontal distance between the axes of the vibrating and rotating components, as well as the dimensions of the rotating and vibrating components.

[0025] The maximum cavitation load that the tested hydraulic machinery can withstand is determined based on the moment of inertia, the torque of the cavitation load, and the rotational acceleration.

[0026] In some implementations, after determining the maximum tolerable cavitation load of the hydraulic machinery under test based on the moment of inertia, cavitation load torque, and rotational acceleration, the measurement method further includes:

[0027] The area of ​​the cavitation load is determined by the horizontal distance between the axis of the vibrating component and the axis of the rotating component.

[0028] The cavitation stress value is determined based on the maximum tolerable cavitation load of the cavitation group and the stress area of ​​the cavitation load.

[0029] Determine the area of ​​a single cavitation bubble based on the image;

[0030] Based on the cavitation stress value and the area of ​​a single cavitation bubble, the maximum cavitation load that the tested hydraulic machinery can withstand for a single cavitation bubble is determined.

[0031] In some embodiments, the cavitation load torque is determined based on the horizontal distance between the axes of the vibrating element and the rotating element, as well as the dimensions of the rotating element and the vibrating element, including:

[0032] The cavitation load torque is determined according to the first formula, which is:

[0033]

[0034] in, The cavitation load torque, For the dimensions of the rotating parts, The dimensions of the vibrating component. It is the horizontal distance between the axis of the vibrating component and the axis of the rotating component.

[0035] In some implementations, the maximum tolerable cavitation load of the tested hydraulic machinery is determined based on the moment of inertia, the cavitation load torque, and the rotational acceleration, including:

[0036] The maximum tolerable cavitation load of a cavitation group is determined according to the second formula, which is:

[0037] FM

[0038] in, For rotational inertia, Let F be the rotational acceleration, F be the cavitation load of the cavitation group, and M be the torque of the cavitation load.

[0039] Thirdly, embodiments of this application provide a computer-readable storage medium storing computer program instructions, which, when executed by a processor, implement the cavitation load measurement method provided in the second aspect.

[0040] This application provides a cavitation load measuring device, including a container holding liquid; a cavitation load generating unit; the cavitation load generating unit includes a vibrating element; the vibrating element is disposed in the liquid contained in the container to trigger the liquid to generate a cavitation load; a rotating unit; the rotating unit is disposed inside the container, spaced apart from the vibrating element, and includes a rotating element and a support frame for supporting the rotating element, the support frame being fixedly disposed with the container, the axis of the rotating element being perpendicular to the axis of the cavitation load generating unit; the rotating element rotates under the action of the cavitation load, and tracer points are marked on the rotating element, the material of the rotating element being determined based on the material of the hydraulic machinery being tested; an image acquisition device is used to acquire images of the container, including images of the rotating element or images of cavitation bubbles in the container; the maximum cavitation load that the rotating element can withstand can be determined based on the multiple images, thereby determining the maximum cavitation load that the hydraulic machinery being tested can withstand. With the above device, the cavitation load can be measured based on the images acquired when the rotating element rotates, making the measurement of the cavitation load independent of the load sensor and the measurement of the material pit size, thereby improving the accuracy of the measurement of the maximum cavitation load that the hydraulic machinery can withstand. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the structure of a cavitation load measuring device provided in an embodiment of this application;

[0042] Figure 2(a) is a partial left view schematic diagram of a cavitation load measuring device provided in an embodiment of this application;

[0043] Figure 2(b) is a partial top view of a cavitation load measuring device provided in an embodiment of this application;

[0044] Figure 3 This is a schematic flowchart of a method for measuring cavitation load provided in an embodiment of this application;

[0045] Figure 4 This is a top view schematic diagram of a cavitation load measuring device provided in a specific embodiment of this application.

[0046] Among them, 100-container; 200-cavitation load generating unit; 210-vibrating component; 220-ultrasonic generator; 230-amplifier; 300-rotating unit; 310-rotating component; 311-rotating body; 312-tracer plate; 320-support frame. Detailed Implementation

[0047] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0048] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0049] The method for measuring cavitation load and the electronic equipment provided in this application will be described in detail below with reference to the accompanying drawings, through specific embodiments and application scenarios.

[0050] Please see Figure 1 This is a schematic diagram of a cavitation load measuring device provided in an embodiment of this application. Figure 1 As shown, the cavitation load measuring device of this application embodiment may include a container 100 containing liquid, a cavitation load generating unit 200, a rotating unit 300, and an image acquisition device (not shown in the figure).

[0051] Specifically, in some embodiments, the container 100 for holding the liquid is a container with corrosion resistance, pressure resistance, and stability. The liquid held is selected according to the application environment of the hydraulic machinery being tested. In one example, the container is made of glass, and the liquid held is water.

[0052] The cavitation load generating unit 200 includes a vibrating element 210; the vibrating element 210 is disposed in the liquid contained in the container 100 and is used to trigger the liquid to generate a cavitation load.

[0053] In some embodiments, the cavitation load generating unit 200 is a part of the measuring device used to generate cavitation loads. The cavitation load generating unit 200 mainly includes a vibrating element 210, which can be a solid cylinder with its bottom immersed in the liquid contained in the container, so as to generate cavitation loads in the liquid when cavitation occurs.

[0054] The rotating unit 300 is disposed inside the container and spaced apart from the vibrating element 210. It includes the rotating element 310 and a support frame 320 for supporting the rotating element 310. The support frame 320 is fixedly disposed with the container 100. The axis of the rotating element 310 is perpendicular to the axis of the cavitation load generating unit 200. The rotating element 310 rotates under the action of the cavitation load. The rotating element 310 is marked with tracer points. The material of the rotating element 310 is determined based on the material of the hydraulic machinery being tested.

[0055] In some embodiments, the rotating unit 300 is disposed in the container, below the cavitation load generating unit 200, and spaced apart from the vibrating element 210 of the cavitation load generating unit 200, i.e., not on the same plane. The rotating unit 300 includes a rotating element 310 and a support frame 320 for supporting the rotating element. The rotating element 310 is a solid cylinder, and the support frame 320 is fixed inside the container 100 to support the rotating element 310. In one example, the rotating element 310 is disposed 0.5 mm below the vibrating element 210, and both ends are mounted on the support frame 320 by studs and nuts, and is immersed in the liquid contained in the container 100.

[0056] The rotating component 310 is marked with tracer points. When cavitation occurs at the bottom of the vibrating component 210, the liquid in the container 100 generates a cavitation load, which causes the rotating component 310 to rotate about its axis. Since the measurement purpose of this embodiment is to measure the maximum cavitation load that a hydraulic machine can withstand, the material of the rotating component 310 is determined based on the material of the hydraulic machine under test to simulate the state of the hydraulic machine during operation. For example, if the hydraulic machine under test is a bladed hydraulic machine and its turbine blade material is a cast nickel-based alloy, then the material of the rotating component 310 is also a cast nickel-based alloy.

[0057] An image acquisition device (not shown in the figure) is used to acquire multiple images of the container 100, including images of the rotating component 310 or images of cavitation generated in the container 100; it can determine the maximum cavitation load that the rotating component can withstand based on the multiple images, thereby determining the maximum cavitation load that the hydraulic machinery under test can withstand.

[0058] In some embodiments, the image acquisition device is used to acquire images of the container 100 during the measurement process. These images include images of cavitation bubbles generated in the water tank 100 and images of tracer points on the rotating member 310. In one example, the image acquisition device is a high-speed camera, which allows for more accurate capture of the tracer points and clearer images of the cavitation bubbles.

[0059] Based on the acquired images from multiple tracer points, the rotation angle of the rotating component 310 at different times can be obtained. After processing the data, the rotational acceleration of the rotating component 310 can be obtained. Based on the acquired cavitation images, the size of a single cavitation bubble can be determined. Based on the rotational acceleration of the rotating component 310 and the size of a single cavitation bubble, the actual cavitation load of this measurement process can be calculated.

[0060] The amplitude of the vibrating element 210 is gradually increased to increase the cavitation load generated each time. Multiple measurements are performed, and the state of the rotating element 310 is observed during the measurements. If cavitation is observed in the rotating element 310 during the i-th measurement, the cavitation load obtained from the (i-1)-th measurement is taken as the maximum cavitation load that the tested hydraulic machinery can withstand.

[0061] Thus, a cavitation load measuring device is provided, comprising: a container holding liquid; a cavitation load generating unit; the cavitation load generating unit including a vibrating element; the vibrating element being disposed in the liquid contained in the container to trigger the liquid to generate a cavitation load; a rotating unit; the rotating unit being disposed inside the container, spaced apart from the vibrating element, including the rotating element and a support frame for supporting the rotating element, the support frame being fixedly disposed to the container, the axis of the rotating element being perpendicular to the axis of the cavitation load generating unit; the rotating element rotating under the action of the cavitation load, the rotating element being marked with tracer points, and the material of the rotating element being the same as the material of the hydraulic machinery being tested; and an image acquisition device for acquiring multiple images of the container, including images of the rotating element or images of cavitation bubbles in the container; the device is able to determine the maximum cavitation load that the rotating element can withstand based on the multiple images, thereby determining the maximum cavitation load that the hydraulic machinery being tested can withstand. With the above device, the cavitation load can be measured based on the images acquired when the rotating element rotates, making the measurement of the cavitation load independent of the load sensor and the measurement of the material pit size, thereby improving the accuracy of the measurement of the maximum cavitation load that the hydraulic machinery can withstand.

[0062] In some implementations, such as Figure 1 As shown, the cavitation load generating unit 200 may also include an ultrasonic generator 220 and an amplifier 230.

[0063] Specifically, the ultrasonic generator 220 is disposed above the container 100 and on the side of the vibrating member away from the rotating member, and the ultrasonic generator is used to generate ultrasonic waves.

[0064] The amplifier 230 is connected at both ends to the ultrasonic generator 220 and the vibrating element 210, respectively, and is used to amplify ultrasonic waves.

[0065] The top of amplifier 230 is connected to the bottom of ultrasonic generator 220, and the bottom of amplifier 230 is connected to the top of vibrating element 210. When measuring cavitation load, the ultrasonic waves emitted by ultrasonic generator 220 are amplified by amplifier 230, generating cavitation at the bottom of vibrating element 210, thereby causing cavitation load in the liquid. This cavitation load is applied to rotating element 310 below vibrating element 210, causing rotating element 310 to rotate around an axis.

[0066] It should be noted that the cavitation load generating unit 200 is not limited to an ultrasonic generator, but can also be driven by other means other than ultrasonic drive that can cause the vibrating element 210 to vibrate and generate cavitation, such as electric drive.

[0067] In some implementations, such as Figure 1 As shown, the rotating component 310 includes a rotating body 311 and a tracer plate 312 sleeved on the rotating body 311. The tracer point is marked on the tracer plate 312. The material of the rotating body 310 is the same as the material of the hydraulic machinery being tested.

[0068] Specifically, the rotating component 310 can be composed of two parts: a rotating body 311 and a tracer plate 312. The rotating body 311 is a solid cylinder, and the tracer plate 312 is a thin circular ring with an inner radius larger than the radius of the rotating body 311. The tracer plate 312 is fitted onto the rotating body 311 and fixed by welding. The tracer point is marked on the tracer plate 312. The material of the rotating body 310 is the same as the material of the hydraulic machinery being measured. When the rotating body 311 rotates around its axis, the tracer plate 312 also rotates at the same speed.

[0069] By marking the tracer point on the tracer plate 312, the image acquisition device can more accurately record the position of the tracer point during rotation, thereby calculating the rotational acceleration of the rotating part 310. It should be noted that the tracer point can also be directly marked on the rotating body 311, that is, the rotating part 310 only includes the rotating body 311, and the tracer plate 312 is not required.

[0070] Please refer to Figures 2(a) and 2(b). Figure 2(a) is a partial left view of a cavitation load measuring device provided in an embodiment of this application, and Figure 2(b) is a partial top view of a cavitation load measuring device provided in an embodiment of this application. As shown in Figures 2(a) and 2(b), in some embodiments, the rotating member 310 and the vibrating member 210 are horizontally offset.

[0071] Specifically, the axis of the rotating unit 300 is horizontal, and the axis of the cavitation load generating unit 200 is vertical. They are perpendicular but not on the same plane; therefore, they are a certain distance apart in the horizontal direction. In Figures 2(a) and 2(b), the horizontal offset distance d between the axis of the rotating component 310 and the axis of the vibrating component 210 is significant. When cavitation occurs at the bottom of the vibrating component 210, the liquid generates a cavitation load. This cavitation load applies an eccentric load to the rotating component 310, causing it to rotate around its axis. Thus, by adjusting the offset distance d, the force-bearing area of ​​the cavitation load (the shaded area in Figure 2(b)) can be accurately controlled, thereby ensuring the accuracy of the measurement results.

[0072] In some implementations, the image acquisition device may include a first image acquisition device and a second image acquisition device.

[0073] Specifically, the first image acquisition device is positioned opposite the side of the rotating component 310 marked with tracer points, and is used to acquire images of the tracer points on the rotating component 310 during the measurement process.

[0074] The first image acquisition device is a device that acquires images of the tracer points. Therefore, with Figure 1 The image shown is a front view of the measuring device. The first image acquisition device can be set on the left or right side of the measuring device to capture and record the position of the trace point on the rotating part 310, thereby calculating the rotational acceleration of the rotating part 310.

[0075] The second image acquisition device is used to acquire images of the cavitation bubbles in container 100.

[0076] The second image acquisition device is a device for acquiring images of the cavitation bubbles in container 100. Figure 1 The image shown is a front view of the measuring device, so the second image acquisition device can be positioned directly in front of the measuring device. This allows for a clearer capture of the cavitation image.

[0077] Please see Figure 3 This is a flowchart illustrating a method for measuring cavitation load provided in an embodiment of this application. Figure 3 As shown, the method for measuring cavitation load in this application embodiment may include the following steps:

[0078] Step 301: Start the cavitation load measurement device to generate cavitation load, and acquire multiple images through the image acquisition device;

[0079] Step 302: Determine the rotational acceleration of the rotating component based on the multiple images acquired by the image acquisition device and the acquisition time of the multiple images;

[0080] Step 303: Determine the moment of inertia of the rotating component based on its dimensions and mass;

[0081] Step 304: Determine the cavitation load torque based on the horizontal distance between the axes of the vibrating component and the rotating component, as well as the dimensions of the rotating component and the vibrating component;

[0082] Step 305: Determine the maximum cavitation load that the hydraulic machinery under test can withstand based on the moment of inertia, the torque of the cavitation load, and the rotational acceleration.

[0083] Specifically, the cavitation load measuring device is first activated to generate a cavitation load, and multiple images are acquired using an image acquisition device. These images can be sent to other devices communicating with the image acquisition device for processing, or the measuring device itself can perform the processing. During processing, the rotational acceleration of the rotating component can be calculated based on the multiple images and their acquisition times.

[0084] It should be noted that the calculation of the rotational acceleration of the rotating component is not limited to calculations based on the acquisition time. In one example, each image acquired by the image acquisition device has a corresponding timestamp, which is automatically generated by the image acquisition device when acquiring the image. The rotational acceleration of the rotating component can be calculated based on multiple images and their timestamps. In another example, the image acquisition interval is preset, and then images are acquired at the same time intervals. The rotational acceleration of the rotating component can also be calculated in this way.

[0085] The dimensions of the vibrating component include its radius R. The dimensions of the rotating component include its length and radius r, which can be measured with calipers, with the length given as 1; the mass m can be measured with a balance. Based on the dimensions and mass of the rotating component, its moment of inertia can be calculated.

[0086]

[0087] In some embodiments, the cavitation load torque is determined based on the horizontal distance between the axes of the vibrating element and the rotating element, as well as the dimensions of the rotating element and the vibrating element. This may include:

[0088] The cavitation load torque is determined according to the first formula, which is:

[0089]

[0090] in, The cavitation load torque, For the dimensions of the rotating parts, The dimensions of the vibrating component. It is the horizontal distance between the axis of the vibrating component and the axis of the rotating component.

[0091] After calculating the cavitation load torque, the cavitation load of the cavitation swarm can be calculated by combining the moment of inertia and rotational acceleration. Multiple measurements are then performed, gradually increasing the cavitation load generated each time, while simultaneously observing the state of the rotating component. If cavitation is observed in the rotating component during the i-th measurement, the cavitation load obtained from the (i-1)-th measurement is taken as the maximum cavitation load that the tested hydraulic machinery can withstand.

[0092] In some implementations, determining the maximum tolerable cavitation load of the tested hydraulic machinery based on the moment of inertia, cavitation load torque, and rotational acceleration may include:

[0093] The maximum tolerable cavitation load of a cavitation group is determined according to the second formula, which is:

[0094] FM

[0095] in, For rotational inertia, Let F be the rotational acceleration, F be the cavitation load of the cavitation group, and M be the torque of the cavitation load.

[0096] In some implementations, after determining the maximum tolerable cavitation load of the hydraulic machinery under test based on the moment of inertia, cavitation load torque, and rotational acceleration, the measurement method may further include:

[0097] The area of ​​the cavitation load is determined by the horizontal distance between the axis of the vibrating component and the axis of the rotating component.

[0098] The cavitation stress value is determined based on the maximum tolerable cavitation load of the cavitation group and the stress area of ​​the cavitation load.

[0099] Determine the area of ​​a single cavitation bubble based on the image;

[0100] Based on the cavitation stress value and the area of ​​the individual cavitation bubble, the maximum cavitation load that the tested hydraulic machinery can withstand for a single cavitation bubble is determined.

[0101] Specifically, based on the calculation of the cavitation load of the cavitation group, the cavitation load of a single cavitation bubble can be further calculated, and then the cavitation load of a single cavitation bubble can be used to evaluate the maximum cavitation load that the hydraulic machinery under test can withstand.

[0102] First, the area subjected to cavitation load can be determined based on the horizontal distance between the axes of the vibrating and rotating components. (See also...) Figure 4 This is a top view schematic diagram of a cavitation load measuring device provided in a specific embodiment of this application. Figure 4As shown, center O is the center of the vibrating component. The area of ​​the ultrasonic cavitation load applied by the vibrating component to the rotating component is the shaded area S, which is the area of ​​the arc where the vibrating component and the rotating component intersect. The starting point of the shaded area S on the x-axis is A, and the ending point is B. The coordinates of point A are (dr, 0), and the coordinates of point B are (R, 0). The area of ​​S is the definite integral from point A to point B, as shown in the following formula:

[0103]

[0104] After obtaining the stress-bearing area S, the cavitation stress value, F / S, can be determined based on the maximum withstandable cavitation load F of the cavitation group and the stress-bearing area S of the cavitation load. Further, the radius a of a single cavitation bubble is obtained from the image acquired by the image acquisition device, and thus the area of ​​a single cavitation bubble is obtained. a 2 Finally, multiplying the cavitation stress value by the area of ​​a single cavitation bubble yields the cavitation load of a single cavitation bubble. Multiple measurements are then performed, gradually increasing the cavitation load each time, while simultaneously observing the state of the rotating component. If cavitation is observed in the rotating component during the i-th measurement, the cavitation load obtained from the (i-1)-th measurement is taken as the maximum cavitation load that the tested hydraulic machinery can withstand.

[0105] Thus, by measuring the rotational speed, the cavitation load can be obtained indirectly without the need for a load sensor or relying on the size of the pit for calculation. There are no assumptions about cavitation deformation, and the measurement, data processing, and calculation methods are relatively simple, which improves the accuracy of the measurement results.

[0106] A third aspect of this application provides a machine-readable storage medium storing instructions that, when executed by a processor, cause the processor to implement the aforementioned method for measuring cavitation load.

[0107] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0108] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 The computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The functions specified in one or more boxes. These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable apparatus for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0109] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0110] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0111] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0112] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0113] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

[0114] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A method for measuring cavitation load, characterized in that, A measuring device for cavitation loads, the measuring device comprising: A container for holding liquids; A cavitation load generating unit; the cavitation load generating unit includes a vibrating element; the vibrating element is disposed in the liquid contained in the container, and the cavitation load generating unit is used to trigger the liquid to generate a cavitation load; A rotating unit is disposed inside the container and spaced apart from the vibrating element. The rotating unit includes a rotating element and a support frame for supporting the rotating element. The support frame is fixedly disposed to the container. The axis of the rotating element is perpendicular to the axis of the cavitation load generating unit. The rotating element rotates under the action of the cavitation load. The rotating element is marked with tracer points. The material of the rotating element is the same as the material of the hydraulic machinery being tested. An image acquisition device is used to acquire multiple images of the container, including images of rotating parts or images of cavitation bubbles in the container; it is able to determine the maximum cavitation load that the rotating parts can withstand based on the multiple images, thereby determining the maximum cavitation load that the tested hydraulic machinery can withstand. The measurement method includes: The cavitation load measuring device is activated to generate the cavitation load, and multiple images are acquired through the image acquisition device. The rotational acceleration of the rotating component is determined based on multiple images acquired by the image acquisition device and the acquisition time of the multiple images; The moment of inertia of the rotating component is determined based on its dimensions and mass. The cavitation load torque is determined based on the horizontal distance between the axis of the vibrating component and the axis of the rotating component, as well as the dimensions of the rotating component and the vibrating component. The maximum withstandable cavitation load of the tested hydraulic machinery is determined based on the moment of inertia, the cavitation load torque, and the rotational acceleration.

2. The measurement method according to claim 1, characterized in that, The rotating component includes a rotating body and a tracer plate sleeved on the rotating body. The tracer point is marked on the tracer plate. The material of the rotating body is the same as the material of the hydraulic machinery being tested.

3. The measurement method according to claim 1, characterized in that, The rotating component and the vibrating component are offset in the horizontal direction.

4. The measurement method according to claim 1, characterized in that, The cavitation load generating unit further includes: An ultrasonic generator is disposed above the container and on the side of the vibrating member away from the rotating member, the ultrasonic generator being used to generate ultrasonic waves; An amplifier, with its two ends connected to the ultrasonic generator and the vibrating element respectively, is used to amplify the ultrasonic waves.

5. The measurement method according to claim 1, characterized in that, The image acquisition device includes: A first image acquisition device is disposed opposite to the side of the rotating component marked with the tracer point, and is used to acquire the image of the tracer point; The second image acquisition device is used to acquire images of the cavitation bubbles in the container.

6. The measurement method according to claim 1, characterized in that, After determining the maximum withstandable cavitation load of the hydraulic machinery under test based on the moment of inertia, the cavitation load torque, and the rotational acceleration, the measurement method further includes: The force-bearing area of ​​the cavitation load is determined based on the horizontal distance between the axis of the vibrating component and the axis of the rotating component. The cavitation stress value is determined based on the maximum tolerable cavitation load of the cavitation group and the force-bearing area of ​​the cavitation load. Determine the area of ​​a single cavitation bubble based on the image; Based on the cavitation stress value and the area of ​​a single cavitation bubble, the maximum cavitation load that the tested hydraulic machinery can withstand for a single cavitation bubble is determined.

7. The measurement method according to claim 1, characterized in that, The determination of the cavitation load torque based on the horizontal distance between the axis of the vibrating component and the axis of the rotating component, as well as the dimensions of the rotating component and the vibrating component, includes: The cavitation load torque is determined according to the first formula, which is: in, The cavitation load torque, The dimensions of the rotating component are... The dimensions of the vibrating element are... The horizontal distance between the axis of the vibrating component and the axis of the rotating component.

8. The measurement method according to claim 1, characterized in that, The determination of the maximum withstandable cavitation load of the tested hydraulic machinery based on the moment of inertia, the cavitation load torque, and the rotational acceleration includes: The maximum tolerable cavitation load of a cavitation cluster is determined according to the second formula, which is: FM in, For rotational inertia, Let F be the rotational acceleration, F be the cavitation load of the cavitation group, and M be the torque of the cavitation load.

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