A cavitation visualization test device for simulating the internal flow pattern of a full flow pump

Abstract

The utility model discloses a kind of cavitation visualization test device for simulating the flow regime inside full-through flow pump, it is related to the field of pump test, include front guide vane body, improved impeller, impeller chamber, guide vane body, water outlet elbow, high-speed camera and pump shaft, by the geometric model of improved impeller and impeller chamber, the internal flow passage of test device is kept consistent with full-through flow pump, that is, equivalent to obtain the complete flow field of full-through flow pump, improved impeller and impeller chamber are manufactured using organic glass, to realize the visualization of its internal state.

Description

Technical Field

[0001] This utility model relates to the field of pump testing, and in particular to a cavitation visualization test device for simulating the internal flow state of a full-flow pump. Background Technology

[0002] Cavitation is a key factor affecting the stable operation of pumps. Essentially, cavitation is a phase change reaction, a process in which the local dynamic pressure of a fluid decreases, causing the liquid phase to transform into water vapor. As the core working component of a water pump, the impeller blades are also a key area for cavitation. The impact pressure from the collapse of bubbles acts on the blade surface, directly affecting the work done by the blades and reducing the efficiency of the water pump. If the pump operates under extreme cavitation conditions for a long time, it will also reduce the service life of the blades and even cause blade damage.

[0003] As a new type of pump, the axial flow pump features a compact structure, convenient installation, and low civil engineering investment, making it particularly suitable for applications requiring high flow rates and low head. The axial flow pump has no internal drive shaft; its main shaft only serves as a supporting structure. The outer edges of the blades are directly welded to the inner wall of the rotor, forming a single unit with it. During operation, the fluid passes directly through the motor's interior. This unique structure eliminates tip clearance, leading scholars and industry professionals to generally agree that the axial flow pump possesses excellent anti-cavitation performance.

[0004] Visualization experiments are the most intuitive and effective technical means to understand the fluid motion state inside a pump. For conventional axial flow pumps, the impeller chamber can be made of plexiglass, allowing high-speed cameras to capture and photograph the cavitation state inside the pump. However, the impeller end wall of a full-flow pump is a rotor core, which cannot be replaced by plexiglass or other transparent materials, thus making direct high-speed photography impossible.

[0005] In summary, although the full-flow pump theoretically has good anti-cavitation performance, there is currently no cavitation visualization test device to match it, and the cavitation state inside its impeller chamber cannot be directly observed to this day. Utility Model Content

[0006] To overcome the above shortcomings, this utility model provides a cavitation visualization test device for simulating the internal flow state of a full-flow pump, aiming to overcome the limitations of current test devices and achieve the goal of directly observing the cavitation state inside the full-flow pump.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A cavitation visualization test device for simulating the internal flow state of a full-flow pump includes a guide vane, an improved impeller, an impeller chamber, a guide vane body, an outlet bend, a high-speed camera, and a pump shaft. The outlet flange of the guide vane body has a slot and connects to the impeller chamber. The impeller chamber is connected to the guide vane body. The guide vane body is connected to the outlet bend. The high-speed camera is placed outside the impeller chamber and is horizontally positioned. The pump shaft passes through the outlet bend, the guide vane body, and the impeller chamber, and the improved impeller is fixedly connected to the pump shaft.

[0009] Both the improved impeller and the impeller chamber are made of plexiglass. The improved impeller consists of an impeller disc, impeller blades, and an impeller hub. There is a disc gap between the impeller disc and the impeller chamber. The size of the disc gap is consistent with the stator-rotor gap of the full-flow pump.

[0010] As a cavitation visualization test device for simulating the internal flow state of a full-flow pump, the impeller chamber and the guide vane body are connected by bolts; the guide vane body and the outlet bend are connected by bolts.

[0011] As a cavitation visualization test device for simulating the internal flow state of a full-flow pump, the improved impeller is fixed to the pump shaft by a key connection.

[0012] As a cavitation visualization test device for simulating the internal flow state of a full-flow pump, the surfaces of the impeller blades and impeller hub are coated with black paint for absorbing laser light.

[0013] As a cavitation visualization test device for simulating the internal flow state of a full-flow pump, the guide vane and the impeller chamber are connected by a rubber seal at the slot.

[0014] As a cavitation visualization test device for simulating the internal flow state of a full-flow pump, the impeller disk and the impeller chamber contain backflow water.

[0015] This utility model has the following beneficial effects:

[0016] This utility model discloses a cavitation visualization test device for simulating the internal flow state of a full-flow pump. It includes a guide vane, an improved impeller, an impeller chamber, a guide vane, an outlet bend, a high-speed camera, and a pump shaft. By improving the geometric model of the impeller and impeller chamber, the internal flow channel of the test device is made consistent with that of the full-flow pump, which is equivalent to obtaining the complete flow field of the full-flow pump. The improved impeller and impeller chamber are both made of plexiglass, thereby realizing the visualization of its internal state. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the pump section assembly according to an embodiment of the present invention;

[0018] Figure 2 This is a simplified structural diagram of the improved impeller 2 in this embodiment of the present invention;

[0019] Figure 3 This is a three-dimensional schematic diagram of the improved impeller of this utility model;

[0020] Figure 4 This is an enlarged view of the gap between the impeller and the disk of this utility model.

[0021] Explanation of reference numerals in the attached figures:

[0022] In the diagram: 1-Guide vane body; 2-Improved impeller; 3-Impeller chamber; 4-Guide vane body; 5-Outlet bend; 6-High-speed camera; 7-Pump shaft; 21-Impeller disc; 22-Impeller blade; 23-Impeller hub; 24-Rubber seal; 25-Disc clearance. Detailed Implementation

[0023] The technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0024] like Figure 1 As shown, the cavitation visualization test device of this utility model includes a front guide vane 1, an improved impeller 2, an impeller chamber 3, a guide vane 4, an outlet bend 5, a high-speed camera 6, and a pump shaft 7. The outlet flange of the front guide vane 1 has a slot and is connected to the impeller chamber 3; the impeller chamber 3 is connected to the guide vane 4; the guide vane 4 is connected to the outlet bend 5; the high-speed camera 6 is placed outside the impeller chamber 3 and is placed horizontally; the pump shaft 7 passes through the outlet bend 5, the guide vane 4, and the impeller chamber 3, and the improved impeller 2 is connected and fixed to the pump shaft 7.

[0025] The impeller chamber 3 is connected to the guide vane body 4 by bolts; the guide vane body 4 is connected to the outlet bend 5 by bolts.

[0026] The improved impeller 2 is fixed to the pump shaft 7 by a key connection.

[0027] like Figure 2As shown, the improved impeller 2 consists of an impeller disk 21, impeller blades 22, and impeller hub 23. The entire improved impeller 2 is manufactured as a single piece using plexiglass. The geometric model of the impeller disk 21 is consistent with the rotor disk model of the full-flow pump. The surfaces of the impeller blades 22 and impeller hub 23 are coated with black paint to absorb laser light and prevent reflections from affecting photographic quality. A three-dimensional schematic diagram of the entire improved impeller 2 is shown below. Figure 3 As shown.

[0028] like Figure 4 As shown, the impeller chamber 3 and the guide vane body 1 are connected in the slot by a rubber seal 24. There is a disc gap 25 between the impeller disc 21 and the impeller chamber 3. The size of the disc gap 25 is consistent with the stator-rotor gap of the full-flow pump. When the pump is running, there is backflow water in the disc gap 25, and the flow direction is shown by the arrow in the figure.

[0029] Through the above steps, the complete flow field inside the full-flow pump has been obtained.

[0030] Figure 1 The test pump section shown is connected to the inlet pipe in front of the guide vane 1 and the outlet pipe behind the outlet bend 5 by bolts, thus obtaining a complete test pipeline. After the pump is started and the test begins, once the model pump is running stably, the cavitation state inside the impeller can be captured by the high-speed camera 6.

[0031] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A cavitation visualization test device for simulating flow regime inside a full flow pump, characterized in that: The system includes a front guide vane (1), an improved impeller (2), an impeller chamber (3), a guide vane (4), an outlet bend (5), a high-speed camera (6), and a pump shaft (7). The outlet flange of the front guide vane (1) has a slot and is connected to the impeller chamber (3). The impeller chamber (3) is connected to the guide vane (4). The guide vane (4) is connected to the outlet bend (5). The high-speed camera (6) is placed outside the impeller chamber (3) and is placed horizontally. The pump shaft (7) passes through the outlet bend (5), the guide vane (4), and the impeller chamber (3). The improved impeller (2) is connected and fixed to the pump shaft (7). The improved impeller (2) and impeller chamber (3) are both made of plexiglass. The improved impeller (2) consists of an impeller disc (21), impeller blades (22) and impeller hub (23). There is a disc gap (25) between the impeller disc (21) and the impeller chamber (3). The size of the disc gap (25) is consistent with the stator-rotor gap of the full-flow pump.

2. The cavitation visualization test device for simulating the internal flow pattern of a full-flow pump according to claim 1, characterized in that: The impeller chamber (3) and the guide vane body (4) are connected by bolts; the guide vane body (4) and the water outlet bend (5) are connected by bolts.

3. The cavitation visualization test device for simulating the internal flow pattern of a full-flow pump according to claim 1, characterized in that: The improved impeller (2) is fixed to the pump shaft (7) by a key connection.

4. The cavitation visualization test device for simulating the internal flow pattern of a full-flow pump according to claim 2, characterized in that: The surfaces of the impeller blades (22) and the impeller hub (23) are coated with black paint for absorbing laser light.

5. The cavitation visualization test device for simulating the internal flow pattern of a full-flow pump according to claim 1, characterized in that: The guide vane (1) and the impeller chamber (3) are connected at the slot by a rubber seal (24).

6. The cavitation visualization test device for simulating the internal flow pattern of a propeller pump according to claim 1, characterized in that: There is backflow water in the disc gap (25) between the impeller disc (21) and the impeller chamber (3).

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