Liquid ring pump rotor blade profile

Abstract

This invention provides a rotor blade profile for a liquid ring pump, the shape of which is determined by the coordinates of an involute equation, wherein the equation is: , ; where, X The x-axis is... Y The vertical axis represents the blade profile. X , Y A segment of a curve formed by continuous changes; the radius of the outer circle of the impeller hub. D The diameter of the impeller. t Let π be the independent variable and π be the value of a circle. b This is an eccentric quantity. Its range of values ​​is... D The value range is 0.2 to 0.3 times; t The value range is 0 to 1; b The value range of is 0 to 1 times the value range of . This invention has many advantages, such as good overall performance, low working loss, high working efficiency, low vibration, low noise, and low cavitation risk.

Description

Technical Field

[0001] This invention belongs to the field of liquid ring pump manufacturing technology, and specifically relates to a liquid ring pump rotor blade profile. Background Technology

[0002] There are many types of rotor blades (also known as impeller blades, which consist of a hub and blades) for existing liquid ring pumps, but in terms of the blade profiles they employ, there are only three types:

[0003] First, the straight line type; second, the circular arc type; third, the combination of straight line and circular arc type.

[0004] Straight blades are easier to manufacture and occupy less space, but the blade curvature has a lower degree of matching with the direction of liquid flow, resulting in greater running resistance, lower efficiency, and poorer reliability.

[0005] The curvature of the arc-shaped blade matches the direction of fluid flow very well, and when driving the working fluid, it can generate a high absolute velocity on the circumference, resulting in relatively high working efficiency and good reliability, but it occupies a larger volume.

[0006] The blade with a combination of straight line and circular arc is formed by combining a straight line with a tangent circular arc, thus achieving a compromise between the two types of blades.

[0007] Looking at the three blade profiles above, each has its advantages and disadvantages. Specifically, in terms of working efficiency, the straight profile is the least efficient. The circular arc profile is more efficient than the straight profile; however, because its curvature is constant, an excessively large circular arc can easily cause liquid to separate from the wall, forming turbulence or vortex zones, thus it is not an ideal profile. As for the combination of straight and circular arc profiles, it combines the advantages of both straight and circular arc blade profiles, but also includes the disadvantages of both, therefore it is not an ideal profile either.

[0008] It should also be noted that although some existing screw pumps and roots pumps use involute blade designs, and the technical performance of involute blades is superior to the three blade profiles mentioned above, thus reflecting the research and development direction of blade profile design to some extent, directly applying the involute blade design used in existing screw pumps or roots pumps to liquid ring pump rotor blades will not produce ideal technical results due to differences in structure and working principle. Therefore, before the completion of the research and development work of this invention, no manufacturer in the field has applied involute blades to liquid ring pump rotor blades. It is evident that how to develop blade profiles specifically for liquid ring pump rotors, taking into account the structural characteristics and working principle of liquid ring pumps, is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0009] The technical problem to be solved by the present invention is to improve the overall performance of the rotor blade profile of the liquid ring pump, especially to improve the working efficiency and reliability of the rotor blade profile of the liquid ring pump, thereby overcoming the defects of the prior art.

[0010] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0011] A rotor blade profile for a liquid ring pump, the shape of which is determined by the coordinates of the involute equation, the formula for calculating the coordinates of the involute equation is as follows: , ; In the formula: X The x-axis is... Y The vertical axis represents the blade profile. X , Y A segment of a curve formed by continuous changes; Let be the radius of the outer circle of the impeller hub. t Let π be the independent variable and π be the value of a circle. b It is the eccentricity.

[0012] The above-described technical solution is the basic technical solution adopted by this invention to solve its technical problem. Based on this basic technical solution, this invention may employ the following additional technical means to better or more specifically solve its technical problem:

[0013] The ，D The diameter is the outer diameter of the impeller.

[0014] Furthermore, the aforementioned t The value range is 0 to 1.

[0015] Furthermore, the aforementioned b The range of values ​​is as described The value range is 0 to 1 times.

[0016] Furthermore, for those caused by X , Y For a curve formed by continuous variation, only the curve at the impeller hub diameter is considered. and impeller outer diameter D The curve segment within the range (i.e.) Figure 1 The curve segment BC in the figure is used as the blade profile.

[0017] Compared with the prior art, the main beneficial effects of the present invention are as follows:

[0018] This invention relates to an involute profile designed for the rotor blades of a liquid ring pump. This profile features a smooth curvature transition, natural unfolding without impact, excellent fluid flow conformity, low risk of separation, and smooth pressure distribution. These characteristics allow the invention to gently guide the fluid during operation, ensuring a very close flow along the pump cavity wall, preventing flow separation, significantly reducing flow losses, and minimizing problems caused by sudden pressure changes, such as cavitation risk, vibration, and noise. In summary, this invention offers numerous advantages, including good overall performance, low operating losses, high efficiency, low vibration, low noise, and low cavitation risk. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the blade profile design scheme in this invention;

[0020] Figure 2 This is a schematic diagram of the end face structure of a liquid ring pump rotor made using the blade profile of this invention.

[0021] Figure 3 This is a schematic diagram of the end face structure of a liquid ring pump rotor made using the blade profile and the arc-shaped blade profile of this invention, respectively (the pump shaft is omitted in the figure).

[0022] In the picture: 1—Blade; 2—Hub; 3—Pump shaft. Detailed Implementation

[0023] To facilitate a thorough understanding of this technical solution by those skilled in the art, an embodiment of the present invention is described below in conjunction with the accompanying drawings.

[0024] like Figure 1 As shown, the rotor blade profile of a liquid ring pump is determined by the coordinates of the involute equation, and the formula for calculating the coordinates of the involute equation is as follows: , ; In the formula: X The x-axis is... Y The vertical axis represents the blade profile. X , Y A segment of a curve formed by continuous changes; Let be the radius of the outer circle of the impeller hub. t Let π be the independent variable and π be the value of a circle. b This refers to the eccentricity (the impeller of a liquid ring pump is usually mounted eccentrically in a nearly circular pump body, so there is a certain amount of eccentricity).

[0025] In this embodiment, the R a=0.2~0.3 D, D The outer diameter of the impeller, that is... The value range is the outer diameter of the impeller. D The value range is 0.2 to 0.3 times (within) and D When the ratio is greater than 0.3 or less than 0.2, the working efficiency of the blade will decrease as the ratio increases or decreases. t The value range is 0 to 1. t When t is 0, the sine function in the above formula has a value of 0, and the cosine function has a value of 1. When t is 1, the sine function has a value of 1, and the cosine function has a value of 0. t The values ​​range from 0 to 1, representing the complete periodic changes of the aforementioned sine and cosine functions; b The range of values ​​is as described The value range is 0 to 1 times ( b and When the ratio is equal to 0 or 1, it represents the two extreme cases of minimum or maximum eccentricity. In the actual implementation of this invention, this ratio is usually between 0 and 1, for example, 0.2, 0.5, 0.8, etc. Furthermore, for those caused by… X , Y For the curve ABCD, which reflects the shape characteristics of the blade profile and is formed by the continuous change of specific values, this embodiment only takes the curve at the impeller hub diameter. and impeller outer diameter D The line segment BC within the range is used as the blade profile.

[0026] The blade profile described above is an involute profile specifically designed for the characteristics of liquid ring pumps in this invention. The end face structure of the liquid ring pump rotor manufactured using the above blade profile is as follows: Figure 2 As shown, the rotor of the liquid ring pump includes blades 1 and a hub 2. Multiple blades 1 (the specific number of blades can be adjusted according to relevant technical standards and actual working conditions) are symmetrically arranged on the outside of the hub 2, and the hub 2 is mounted on the pump shaft 3 of the liquid ring pump.

[0027] Figure 3This diagram illustrates the end-face structure of a liquid ring pump rotor made using the blade profile of this invention and the circular arc blade profile of the prior art (the pump shaft is omitted in the diagram). The dashed lines (excluding the circumference formed by the rotation of the liquid ring pump rotor) represent the circular arc blades, while the solid lines (excluding the circumference of the hub) represent the involute blades made according to this invention. Compared to the constant curvature of the circular arc blades, the liquid ring pump rotor using the involute blades of this invention has a blade curvature that gradually decreases from infinity, resulting in a very smooth transition. However, when the blades finally leave the outer surface of the rotor, the total curvature of the profile is greater than that of the circular arc blade. This allows the liquid to gain more kinetic energy when leaving the outer circle of the rotor than a rotor using a circular arc blade, thus enabling the rotor to achieve a higher pressure ratio during operation.

[0028] In summary, the involute profile designed for the rotor blades of the liquid ring pump in this invention features a smooth curvature transition, natural unfolding without impact, excellent fluid flow conformity, low risk of separation, and smooth pressure distribution. These characteristics enable the invention to gently guide the fluid during operation, allowing it to flow very closely along the pump cavity wall, avoiding flow separation, significantly reducing flow losses, and minimizing various problems caused by sudden pressure changes, such as cavitation risk, vibration, and noise. In conclusion, this invention offers numerous advantages, including good overall performance, low operating losses, high efficiency, low vibration, low noise, and low cavitation risk.

Claims

1. A rotor blade profile for a liquid ring pump, characterized in that: The shape of the blade profile is determined by the coordinates of the involute equation, and the formula for calculating the coordinates of the involute equation is as follows: ， ; In the formula: X The x-axis is... Y The vertical axis represents the blade profile. X , Y A segment of a curve formed by continuous changes; Let be the radius of the outer circle of the impeller hub. t Let π be the independent variable and π be the value of a circle. b It is the eccentricity.

2. The rotor blade profile of the liquid ring pump as described in claim 1, characterized in that: The ，D The diameter is the outer diameter of the impeller.

3. The rotor blade profile of the liquid ring pump as described in claim 1, characterized in that: The t The value range is 0 to 1.

4. The rotor blade profile of the liquid ring pump as described in claim 1, characterized in that: The b The range of values ​​is as described The value range is 0 to 1 times.

5. The rotor blade profile of the liquid ring pump as described in any one of claims 1 to 4, characterized in that: For by X , Y For a curve formed by continuous variation, only the curve at the impeller hub diameter is considered. and impeller outer diameter D The line segments within the range are used as blade profiles.

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