Double-volute centrifugal pump partition plate structure for restraining flow separation

Abstract

The utility model discloses a double-volute centrifugal pump partition plate structure for restraining flow separation, which comprises a partition tongue, a partition plate, a volute inner flow channel and a volute outer flow channel, and the volute inner flow channel and the volute outer flow channel are formed by partition of the partition plate. A first transition groove and a second transition groove are formed in the two ends of the sine-shaped groove respectively. The sine-shaped groove is formed in the outer surface of the head of the partition plate, so that when the centrifugal pump operates under a deviated working condition, the sine-shaped groove structure plays a certain role in guiding flow, the impact effect between high-speed fluid flowing out of an impeller and the head of the partition plate is reduced, and the service life of the partition plate is prolonged. The flow separation phenomenon of an outer flow channel of the volute near the head of the partition plate under a deviated working condition is effectively inhibited; meanwhile, the sine-shaped groove structure can effectively restrain flow separation on the back face of the partition plate and eliminate flow separation vortexes of an outer flow channel of the volute under the deflection working condition, so that the centrifugal pump obtains high lift and efficiency, and the running stability of the centrifugal pump is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of centrifugal pump volutes, in particular to a double-volute centrifugal pump diaphragm structure for suppressing flow separation. Background Art

[0002] As an energy conversion and fluid transportation device, the centrifugal pump has the advantages of simple and compact structure, long service life, and easy maintenance and management. It is widely used in agricultural irrigation, chemical petroleum, transportation and other fields. As one of the main components of the centrifugal pump, the structure of the volute has a great influence on the performance of the centrifugal pump. At present, many scholars have confirmed through research that on the basis of the single volute structure, the double volute structure formed by setting a partition structure inside the volute can effectively reduce the impeller radial force generated by the pump during operation and improve its noise, vibration and other problems. Therefore, the double volute centrifugal pump has been widely used.

[0003] However, the flow structure inside the volute of a centrifugal pump is complex. When the pump is running under biased conditions, the high-speed fluid flowing out of the impeller collides with the head of the diaphragm due to the blocking effect of the diaphragm, which causes flow separation in the volute outer flow channel near the diaphragm head and generates a vortex, which in turn affects the flow pattern inside the volute. At the same time, it causes large fluctuations in the fluid pressure near the diaphragm head, resulting in energy loss and a decrease in the efficiency and head of the pump; and flow separation will cause an obvious low-pressure area at the starting position of the diaphragm outer flow channel, which is a location prone to cavitation. Therefore, it is necessary to study a method to suppress flow separation in view of the flow separation phenomenon near the diaphragm head of the volute outer flow channel, so as to ensure that the volute has a better flow pattern when the centrifugal pump is running under biased conditions. Utility Model Content

[0004] The utility model aims to provide a double-volute centrifugal pump diaphragm structure for suppressing flow separation, which can effectively improve the flow separation phenomenon caused by the impact of water flow on the diaphragm head when the centrifugal pump is running under biased working conditions, and solve the above-mentioned problems existing in the prior art.

[0005] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0006] The utility model discloses a double-volute centrifugal pump diaphragm structure for suppressing flow separation, comprising a diaphragm tongue, a diaphragm, and a volute inner flow channel and a volute outer flow channel separated by the diaphragm, wherein the outer surface of the diaphragm head is provided with a sinusoidal groove with a sinusoidal cross-section, and a first transition groove and a second transition groove are respectively provided at both ends of the sinusoidal groove.

[0007] Furthermore, the characteristic points (x, y) of the cross-sectional profile of the sinusoidal groove on the outer surface of the partition head satisfy the following equation:

[0008]

[0009] Among them, the midpoint of the starting line segment of the arc on the outer surface of the partition head is taken as the origin, the starting segment of the arc is taken as the X-axis, the vertical direction along the X-axis at the origin is taken as the Y-axis, L is the width of the middle cross-section of the partition head, and D is the diameter of the arc of the partition head.

[0010] Furthermore, the sinusoidal groove is formed by rotating the contour line 25° around the volute base circle in a counterclockwise direction and 150° around the arc of the partition head in a clockwise direction.

[0011] Furthermore, the second transition groove is close to the partition head, and the edge of the second transition groove is processed with a fillet with a radius of 1 mm.

[0012] Compared with the prior art, the beneficial technical effects of the utility model are:

[0013] The double-volute centrifugal pump diaphragm structure for suppressing flow separation of the utility model has a sinusoidal groove on the outer surface of the diaphragm head, so that when the centrifugal pump is running under biased conditions, the sinusoidal groove structure plays a certain flow guiding role, reduces the impact of the high-speed fluid flowing out of the impeller and the diaphragm head, and effectively suppresses the flow separation phenomenon in the volute outer flow channel near the diaphragm head under biased conditions; in addition, the sinusoidal groove structure can effectively curb the flow separation on the back side of the diaphragm, eliminate the flow separation vortex in the volute outer flow channel under biased conditions, thereby reducing the energy loss in the volute flow channel of the centrifugal pump, enabling the centrifugal pump to obtain a higher head and efficiency, and improving the stability of the operation of the centrifugal pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0015] Figure 1 It is a schematic diagram of the overall structure of the double volute centrifugal pump diaphragm structure for suppressing flow separation of the utility model;

[0016] Figure 2 It is a partial structural schematic diagram of a partition in the partition structure of a double volute centrifugal pump for suppressing flow separation of the utility model;

[0017] Figure 3 It is a design principle diagram of the partition in the partition structure of the double volute centrifugal pump for suppressing flow separation of the utility model;

[0018] Figure 4It is a schematic diagram of the local structure of the diaphragm head in the diaphragm structure of a double-volute centrifugal pump for suppressing flow separation of the utility model.

[0019] Explanation of the reference numerals: 1. tongue; 2. partition plate; 3. flow channel inside the volute; 4. flow channel outside the volute; 5. sinusoidal groove; 6. first transition groove; 7. second transition groove; 8. rounded corner. DETAILED DESCRIPTION

[0020] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0021] In the description of the present utility model, it should be understood that the terms "length", "width", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. 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 utility model, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0022] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 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.

[0023] The technical solution provided by the embodiment of the utility model is described in detail below in conjunction with the accompanying drawings.

[0024] like Figures 1 to 4As shown, the double-volute centrifugal pump diaphragm structure for suppressing flow separation in an embodiment of the utility model comprises a diaphragm 1, a diaphragm 2, and a volute inner flow channel 3 and a volute outer flow channel 4 separated by the diaphragm 2, wherein the diaphragm 2 is bent toward the volute outer flow channel 4, and a sinusoidal groove 5 with a sinusoidal cross-section is provided on the outer surface of the head of the diaphragm 2, and a first transition groove 6 and a second transition groove 7 are respectively provided at both ends of the sinusoidal groove 5.

[0025] like Figure 3 As shown, the characteristic points (x, y) of the cross-sectional profile of the sinusoidal groove 5 on the outer surface of the head of the partition 2 satisfy the following equation:

[0026]

[0027] Among them, the midpoint of the starting line segment of the arc on the outer surface of the partition head 2 is taken as the origin, the starting segment of the arc is taken as the X-axis, the vertical direction along the X-axis at the origin is taken as the Y-axis, L is the width of the middle cross-section of the partition head 2, and D is the diameter of the arc at the partition head 2.

[0028] After obtaining the characteristic points (x, y) of the cross-sectional profile of the sinusoidal groove 5, the initial shape of the cross section of the sinusoidal groove 5 is drawn by fitting according to the characteristic points (x, y) of the cross-sectional profile of the sinusoidal groove 5. According to the obtained cross-sectional curve of the sinusoidal groove 5, firstly, the cross-sectional curve of the sinusoidal groove 5 is rotated with the center of the volute base circle as the center, and is cut along the surface of the partition 2. The specific cutting range is 25° counterclockwise around the center of the base circle. Secondly, the cross-sectional curve of the sinusoidal groove 5 is rotated with the center of the arc of the head of the partition 2 as the center, and is cut along the surface of the partition 2. The specific cutting range is 150° clockwise around the center of the arc of the head of the partition 2. Finally, in order to make the sinusoidal groove 5 completely penetrate the surface of the partition 2, the cross-sectional surface of the sinusoidal groove after the lofting and cutting is stretched and cut to form the first transition groove 6 and the second transition groove 7 respectively, until it completely penetrates the surface of the partition 2. That is, the sinusoidal groove 5 is formed by rotating the contour line 25° around the base circle of the volute in the counterclockwise direction and 150° around the arc of the head of the partition plate 2 in the clockwise direction.

[0029] like Figure 4 As shown, the second transition groove 7 is arranged on one side close to the head of the partition 2. By processing a fillet 8 with a radius of 1 mm on the edge of the second transition groove 7, a natural transition can be achieved.

[0030] When the double-volute centrifugal pump diaphragm structure for suppressing flow separation of this embodiment is in use, inside the centrifugal pump, after the high-speed fluid flowing out of the impeller collides with the head of the diaphragm 2, the fluid medium in the outer flow channel of the volute will smoothly flow into the outer flow channel 4 of the volute along the sinusoidal groove 5 at the head of the diaphragm 2, which helps to suppress the flow separation phenomenon in the outer flow channel 4 of the volute near the head of the diaphragm 2.

[0031] The double-volute centrifugal pump diaphragm structure for suppressing flow separation of the utility model effectively suppresses the flow separation phenomenon in the volute outer flow channel near the diaphragm head under abnormal working conditions by arranging a sinusoidal groove with a flow guiding function on the surface of the diaphragm head. At the same time, it can effectively eliminate the detached vortex in the volute outer flow channel under abnormal working conditions, so that the centrifugal pump obtains a higher head and efficiency, and improves the stability of the operation of the centrifugal pump.

[0032] The embodiments described above are only descriptions of the preferred methods of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the protection scope determined by the claims of the present invention.

Claims

1. A double volute centrifugal pump diaphragm structure for suppressing flow separation, characterized in that: It includes a partition tongue, a partition plate, and a volute inner flow channel and a volute outer flow channel separated by the partition plate. The outer surface of the partition plate head is provided with a sinusoidal groove with a sinusoidal cross-section, and the two ends of the sinusoidal groove are respectively provided with a first transition groove and a second transition groove.

2. A double volute centrifugal pump diaphragm structure for suppressing flow separation according to claim 1, characterized in that: The characteristic points (x, y) of the cross-sectional profile of the sinusoidal groove on the outer surface of the partition head satisfy the following equation: Among them, the midpoint of the starting line segment of the arc on the outer surface of the partition head is taken as the origin, the starting segment of the arc is taken as the X-axis, the vertical direction along the X-axis at the origin is taken as the Y-axis, L is the width of the middle cross-section of the partition head, and D is the diameter of the arc of the partition head.

3. A double volute centrifugal pump diaphragm structure for suppressing flow separation according to claim 2, characterized in that: The sinusoidal groove is formed by rotating the contour line 25° around the volute base circle in the counterclockwise direction and 150° around the arc of the partition head in the clockwise direction.

4. A double volute centrifugal pump diaphragm structure for suppressing flow separation according to any one of claims 1 to 3, characterized in that: The second transition groove is close to the partition head, and the edge of the second transition groove is processed with a fillet with a radius of 1 mm.

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