Experimental device for simulating erosion and cavitation

Abstract

The invention provides an experimental device for simulating erosion and cavitation erosion. The experimental device comprises an outer box, an ultrasonic vibrator arranged in the outer box and a clamp connected to the ultrasonic vibrator and used for fixing a sample. The outer box is further provided with a closed cavity, and an atomizer, an air pump and a communicating pipe communicating with the cavity are arranged in the cavity. The ultrasonic vibrator drives the sample to vibrate at a high speed, the atomizer converts water into water vapor, and high-speed water flow is formed under pressurization of the air pump and passes through the communicating pipe, so that the water vapor (tiny liquid drops) impacts the surface of the sample in an accelerated manner, and an erosion experiment is simulated; meanwhile, water drops attached to the sample are cavitated, gas nuclei in water grow into steam bubbles, and the steam bubbles are accumulated, flow, split and collapsed to generate high-strength shock waves, so that a cavitation experiment is simulated; the device is more in line with the actual working environment of the blade, so that the tested structure is more accurate and has higher reference value.

Description

Technical Field

[0001] The invention relates to the technical field of experimental verification devices, and in particular to an experimental device for simulating erosion and cavitation. Background Art

[0002] Existing cavitation simulation devices usually require placing a sample in a water environment and utilizing the ultrasonic cavitation effect of ultrasonic vibration in water to generate bubbles to impact the sample to simulate the cavitation environment.

[0003] However, for steam turbine blades, the working environment is that the blades are in a high-speed water vapor environment, and are also subject to the erosion effect of high-speed water vapor (droplets); and the existing cavitation simulation device cannot reproduce the actual working environment of the blades; at the same time, if the existing cavitation simulation device is used and the steam turbine blades are placed in a water environment, the uncontrollable factors of the experimental simulation are increased, which can easily lead to deviations in the results of the simulation test and cannot accurately reflect whether the performance of the steam turbine blades meets the standards. Summary of the invention

[0004] In view of this, an object of the present invention is to provide an experimental device for simulating erosion and cavitation to solve the above problems.

[0005] The present invention adopts the following scheme:

[0006] The present application provides an experimental device for simulating erosion and cavitation, comprising an outer box, an ultrasonic vibrator placed in the outer box, and a fixture connected to the ultrasonic vibrator for fixing a sample; the outer box is also provided with a closed chamber, the chamber is provided with an atomizer, an air pump connected to the chamber, and a connecting pipe connected to the chamber;

[0007] The atomizer is used to convert water into water vapor; the air pump is used to pressurize the chamber so that the water vapor can be accelerated through the connecting pipe to impact the surface of the sample; the ultrasonic vibrator is used to cause cavitation of water droplets attached to the sample.

[0008] Furthermore, one end of the connecting tube is fixedly connected to the chamber, and the other end can be adjusted to be close to or away from the sample surface.

[0009] Furthermore, the connecting pipe includes a first connecting pipe with one end fixedly connected to the chamber, and a second connecting pipe screwed to the other end of the first connecting pipe.

[0010] Furthermore, a Laval nozzle is provided at the other end of the connecting pipe, and the angle of the outlet of the Laval nozzle can be adjusted.

[0011] Furthermore, it includes an adjusting member; a first supporting portion is provided on at least one side of the Laval nozzle, and a slot is provided on the first supporting portion; a second supporting portion is provided on the outer side of the connecting pipe opposite to the first supporting portion, and a first meshing tooth is provided on the outer periphery of the second supporting portion; the adjusting member is movably clamped on the slot, and a second meshing tooth adapted to the first meshing tooth is provided on its inner peripheral wall.

[0012] Furthermore, the angle of the second meshing tooth relative to the first meshing tooth per rotation of one tooth is 1 degree.

[0013] Furthermore, the air pump is used to pressurize the chamber so that the water vapor flow rate reaches 50-400 m / s.

[0014] Furthermore, the inlet diameter of the Laval nozzle is 50 mm, the outlet diameter is 30 mm, and the throat diameter is 10 mm.

[0015] Furthermore, the outlet of the Laval nozzle forms an angle of 16-18 degrees with the sample.

[0016] Furthermore, a water pump is included, which is connected to the bottom of the outer box and the chamber through a pipeline.

[0017] By adopting the above technical solution, the present invention can achieve the following technical effects:

[0018] The invention provides an experimental device for simulating erosion and cavitation, comprising an outer box, an ultrasonic vibrator placed in the outer box, and a clamp connected to the ultrasonic vibrator for fixing a sample; the outer box is also provided with a closed chamber, and the chamber is provided with an atomizer, an air pump, and a connecting pipe connected with the chamber; the ultrasonic vibrator drives the sample to vibrate at a high speed, and the atomizer converts water into water vapor, and a high-speed water flow is formed under the pressure of the air pump to pass through the connecting pipe, so that the water vapor is accelerated to impact on the surface of the sample, thereby simulating an erosion experiment; at the same time, small water droplets attached to the sample undergo cavitation under the action of the ultrasonic vibrator, and gas nuclei in the water grow into bubbles, and accumulate, flow, split, and collapse to generate high-intensity shock waves, thereby simulating a cavitation experiment; it is more in line with the actual working environment of the blade, so that the test structure is more accurate and has more reference value. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a schematic structural diagram of an experimental device for simulating erosion and cavitation according to an embodiment of the present invention without a sealing cover installed;

[0021] Figure 2 It is a schematic diagram of the cross-sectional structure of an experimental device for simulating erosion and cavitation according to an embodiment of the present invention;

[0022] Figure 3 It is a schematic diagram of a partial cross-sectional structure of an experimental device for simulating erosion and cavitation according to an embodiment of the present invention;

[0023] Figure 4 yes Figure 1 A is a schematic diagram of the enlarged structure of the middle part;

[0024] Figure 5 yes Figure 3 A schematic diagram of the enlarged structure of B;

[0025] Icons: outer box 1, ultrasonic vibrator 2, clamp 3, chamber 4, atomizer 5, air pump 6, sealing cover 7, first connecting pipe 8, second connecting pipe 9, adjustment member 10, first supporting portion 11, slot 12, second supporting portion 13, first meshing teeth 14, clamping portion 15, water pump 16, pipeline 17, second meshing teeth 18, Laval nozzle 19, inlet 20, outlet 21, throat 22. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the invention claimed for protection, but merely represents the selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention.

[0027] Example

[0028] Combination Figures 1 to 5As shown, this embodiment provides an experimental device for simulating erosion and cavitation, comprising an outer box 1, an ultrasonic vibrator 2 placed in the outer box 1, and a fixture 3 connected to the ultrasonic vibrator 2 for fixing a sample; the outer box 1 is also provided with a closed chamber 4, and the chamber 4 is provided with an atomizer 5, an air pump 6 connected to the chamber 4, and a connecting pipe connected to the chamber 4;

[0029] The atomizer 5 is used to convert water into water vapor; the air pump 6 is used to pressurize the chamber 4 so that the water vapor can be accelerated through the connecting pipe to impact the surface of the sample; the ultrasonic vibrator 2 is used to generate cavitation on the water droplets attached to the sample to form bubbles.

[0030] Specifically, in this embodiment, the outer box 1 is a box with an upper opening, and the ultrasonic vibrator 2 is arranged at the bottom thereof. A clamp 3 for fixing the sample (i.e., the turbine blade) is arranged on the ultrasonic vibrator 2; in this embodiment, the clamp 3 is clamped and adjusted by bolts to adapt to the samples of different sizes. The chamber 4 is arranged on the upper inner side of the outer box 1, and a sealing cover 7 is detachably arranged on the upper opening thereof, and a sealing gasket is arranged between the sealing cover 7 and the upper opening to form a good sealing environment for the chamber 4.

[0031] The chamber 4 is provided with an atomizer 5, which is used to atomize the water in the chamber 4 into water vapor; specifically, in this embodiment, the vibration frequency of the atomizer 5 is set to 108KMHz, so that the water droplets formed by the water mist are about 10-15μm. The chamber 4 is also provided with the air pump 6, which can adjust the pressure to 0.6-1.5Mpa, and is used to pressurize the chamber 4 so that the water vapor can be accelerated through the connecting pipe to impact the surface of the sample. The water can be distilled water, salt water or water containing solid particles.

[0032] The ultrasonic vibrator 2 mentioned above drives the sample to vibrate at high speed, and the atomizer 5 converts water into water vapor, and forms a high-speed water flow through the connecting pipe under the pressure of the air pump 6, so that the water vapor is accelerated to impact the surface of the sample, thereby simulating the erosion experiment. At the same time, the small water droplets attached to the sample undergo cavitation under the action of the ultrasonic vibrator 2, and the gas nuclei in the water grow into bubbles, and accumulate, flow, split, and collapse to produce high-intensity shock waves, thereby simulating the cavitation experiment. It accurately restores the actual working environment of the blade, realizes the experiment in a high-speed wet steam environment, avoids the uncontrollable factors caused by placing the sample in a water environment, eliminates the factors of corrosion of the sample by the water environment, and makes the test results more accurate and more valuable for reference.

[0033] In this embodiment, the connecting pipe includes a first connecting pipe 8 fixed at one end thereof and connected to the chamber 4, and a second connecting pipe 9 screwed to the other end of the first connecting pipe 8; the first connecting pipe 8 is L-shaped, and the other end thereof is vertically downwardly arranged; the second connecting pipe 9 is adjustably connected to the first connecting pipe 8 by a threaded connection. A Laval nozzle 19 is arranged at the other end of the connecting pipe, so that the distance between the outlet 21 of the Laval nozzle 19 and the sample can be adjusted between 50 mm and 200 mm.

[0034] In this embodiment, if Figure 4 and Figure 5 As shown, the outlet 21 of the Laval nozzle 19 can be adjusted in angle. Specifically, it includes an adjusting member 10; the inlet of the Laval nozzle 19 is spherical and can be rotatably arranged at the nozzle of the second connecting pipe 9. A first supporting portion 11 is arranged on one side of the Laval nozzle 19, and a clamping groove 12 is arranged on the supporting portion; a second supporting portion 13 is arranged on the outer side of the connecting pipe opposite to the first supporting portion 11, and a first meshing tooth 14 is arranged on the outer periphery of the second supporting portion 13; a clamping portion 15 is arranged on the adjusting member 10, which is movably clamped on the clamping groove 12, and a second meshing tooth 18 adapted to the first meshing tooth 14 is arranged on the inner peripheral wall of the adjusting member 10; the clamping portion 15 can be movably clamped on the clamping groove 12, so as to realize the meshing of the second meshing tooth 18 with the first meshing tooth 14. The adjusting member 10 rotates to mesh with the first meshing teeth 14 through the second meshing teeth 18 to drive the Laval nozzle 19 to rotate; specifically, the first meshing teeth 14 are fixed, and when the adjusting member 10 rotates, the second meshing teeth 18 rotate on the first meshing teeth 14, thereby driving the Laval nozzle 19 to rotate, thereby adjusting the outlet 21 angle of the Laval nozzle 19. The tooth shape setting can better index and improve the rotation accuracy, and also enables the Laval nozzle 19 to be better movably connected with the second connecting pipe 9 through the adjusting member 10. And the angle of the second meshing teeth 18 relative to the first meshing teeth 14 for each rotation of one tooth is set to 1 degree, thereby achieving precise angle adjustment.

[0035] Preferably, the outlet 21 of the Laval nozzle 19 forms an angle of 16-18 degrees with the sample, so as to achieve the best experimental effect.

[0036] In this embodiment, the erosion experiment of the steam turbine blade is carried out. Based on the requirement of airflow acceleration, the diameter of the inlet 20 of the Laval nozzle 19 is set to 50 mm, the diameter of the outlet 21 is set to 30 mm, and the diameter of the throat 22 is set to 10 mm. The air pump 6 is pressurized to make the water vapor flow rate reach 50-400 m / s, and the surface of the sample is impacted at high speed. The water vapor flow rate is set according to the actual test requirements and to simulate the actual working environment of the steam turbine blade.

[0037] In this embodiment, a water pump 16 is also included, which is connected to the bottom of the outer box 1 and the chamber 4 through a pipeline 17 to achieve water recycling and make the experimental simulation more environmentally friendly.

[0038] The experimental device for simulating erosion and cavitation greatly increases the impact speed of water vapor and correctly simulates the erosion environment of the sample through the arrangement of the ultrasonic vibrator 2, the air pump 6, and the Laval nozzle 19; and the ultrasonic vibrator 2 causes cavitation in the small water droplets attached to the surface of the sample, so that cavitation simulation can be performed at the same time as erosion simulation; and it is more in line with the actual working environment of the blade.

[0039] The above are only preferred implementations of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention.

[0040] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0041] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0042] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0043] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

Claims

1. An experimental device for simulating erosion and cavitation, comprising an outer box, an ultrasonic vibrator placed in the outer box, and a fixture connected to the ultrasonic vibrator for fixing a sample; characterized in that: The outer box is also provided with a closed chamber, in which an atomizer, an air pump connected to the chamber, and a connecting pipe connected to the chamber are arranged; The atomizer is used to convert water into water vapor; the air pump is used to pressurize the chamber so that the water vapor can be accelerated through the connecting pipe to impact the surface of the sample; the ultrasonic vibrator is used to cause cavitation of water droplets attached to the sample.

2. The experimental device for simulating erosion and cavitation according to claim 1, characterized in that: One end of the connecting tube is fixedly connected to the chamber, and the other end can be adjusted to be close to or away from the sample surface.

3. The experimental device for simulating erosion and cavitation according to claim 2, characterized in that: The connecting pipe comprises a first connecting pipe with one end fixedly connected to the chamber, and a second connecting pipe screwed to the other end of the first connecting pipe.

4. The experimental device for simulating erosion and cavitation according to claim 1 or 2, characterized in that: A Laval nozzle is arranged at the other end of the connecting pipe, and the outlet of the Laval nozzle can be adjusted in angle.

5. The experimental device for simulating erosion and cavitation according to claim 4, characterized in that: It includes an adjusting member; a first supporting portion is provided on at least one side of the Laval nozzle, and a slot is provided on the first supporting portion; a second supporting portion is provided on the outer side of the connecting pipe opposite to the first supporting portion, and a first meshing tooth is provided on the outer periphery of the second supporting portion; the adjusting member is movably clamped on the slot, and a second meshing tooth matched with the first meshing tooth is provided on its inner peripheral wall.

6. The experimental device for simulating erosion and cavitation according to claim 5, characterized in that: The angle of the second meshing tooth relative to the first meshing tooth per rotation of one tooth is 1 degree.

7. The experimental device for simulating erosion and cavitation according to claim 4, characterized in that: The air pump is used to pressurize the chamber so that the water vapor flow rate reaches 50-400m / s.

8. The experimental device for simulating erosion and cavitation according to claim 7, characterized in that: The Laval nozzle has an inlet diameter of 50 mm, an outlet diameter of 30 mm, and a throat diameter of 10 mm.

9. The experimental device for simulating erosion and cavitation according to claim 8, characterized in that: The outlet of the Laval nozzle forms an angle of 16-18 degrees with the sample.

10. The experimental device for simulating erosion and cavitation according to claim 1, characterized in that: A water pump is also included, which is connected to the bottom of the outer box and the chamber through a pipeline.

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