A vane design method for optimizing starting transient performance and a vane pump designed thereby

Abstract

The present invention discloses a vane design method for optimizing starting transient performance and a vane pump designed thereby. In the vane design method for optimizing starting transient performance, the vane has a vane inlet edge and a vane outlet edge, and the vane is configured such that the magnitudes of the angles of attack at any point on the vane inlet edge are different. According to the vane design method for optimizing starting transient performance of the embodiments of the present invention, by designing the angles of attack on the vane inlet edge, the inlet loss of the vane can be effectively reduced, the pressure distribution on the vane inlet edge can be optimized, thereby suppressing flow separation, increasing the stable flow rate at the end of starting, and improving the starting transient performance.

Description

Technical Field

[0001] The present invention relates to the technical field of vane pump design, and more particularly, to a vane design method for optimizing starting transient performance and a vane pump designed thereby. Background Art

[0002] Currently, vane pumps are widely used in industries such as water conservancy, electric power, and ship hydraulic propulsion. During the design process of a vane pump, if the magnitude of the inlet incidence angle of the vane is unreasonable, flow separation, rotating stall, and other effects will occur in the pump, resulting in deteriorated flow patterns and decreased performance. Therefore, there is research value in the design of the incidence angle. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, an object of the present invention is to provide a vane design method for optimizing starting transient performance, and the vane designed by the design method can effectively reduce the inlet loss of the vane, suppress flow separation, and improve the starting transient performance.

[0004] The present invention also provides a vane pump.

[0005] According to the vane design method for optimizing starting transient performance of an embodiment of the present invention, the vane has a vane inlet edge and a vane outlet edge, and the vane is configured such that the magnitudes of the incidence angles at any point on the vane inlet edge are different.

[0006] According to the vane design method for optimizing starting transient performance of an embodiment of the present invention, by designing the incidence angle on the vane inlet edge, the inlet loss of the vane can be effectively reduced, the pressure distribution on the vane inlet edge can be optimized, thereby suppressing flow separation, increasing the stable flow rate at the end of starting, and improving the starting transient performance.

[0007] According to the vane design method for optimizing starting transient performance of an embodiment of the present invention, the magnitude of the incidence angle of the vane at any point on the vane inlet edge satisfies a cubic function distribution law with respect to the ratio of the length of the point from the end of the vane inlet edge to the length of the vane inlet edge.

[0008] According to the vane pump of an embodiment of the present invention, the magnitude of the incidence angle at any point on the vane inlet edge satisfies:

[0009]

[0010] wherein, Δβ(x) is the magnitude of the incidence angle at any point on the vane inlet edge, L is the length of the vane inlet edge, x is the length of any point on the vane inlet edge from the first end of the vane inlet edge, and the first end is the connection end of the vane inlet edge and the hub.

[0011] According to the blade design method for optimizing starting transient performance according to an embodiment of the present invention, in the axial plane coordinate system z-r, the z-axis is the axis where the rotation axis is located, z is the coordinate of any point on the blade inlet edge on the z-axis, r is the perpendicular distance from any point on the blade inlet edge to the rotation axis, and the length of the blade inlet edge and the length from any point on the blade inlet edge to the first end of the blade inlet edge satisfy:

[0012]

[0013] wherein, r0 is the perpendicular distance from the first end to the rotation axis, r1 is the perpendicular distance from the second end of the blade inlet edge to the rotation axis, z0 is the coordinate of the first end on the z-axis, and z1 is the coordinate of the second end on the z-axis.

[0014] According to the blade design method for optimizing starting transient performance according to an embodiment of the present invention, the blade is disposed between a hub and a rim, the blade is connected to the hub, there is a gap between the blade and the rim to rotate relative to the rim, the connection end of the blade inlet edge and the hub is the first end, the end of the blade inlet edge adjacent to the rim is the second end, and the magnitude of the incidence angle gradually increases from the first end to the second end.

[0015] According to the blade design method for optimizing starting transient performance according to an embodiment of the present invention, the value of the incidence angle at the connection end of the blade inlet edge and the hub is less than zero, and the value of the incidence angle at the end of the blade inlet edge adjacent to the rim is zero.

[0016] According to the blade design method for optimizing starting transient performance according to an embodiment of the present invention, the blade is disposed between a hub and a rim, a fluid is adapted to flow in a flow passage formed by the hub and the rim, on the plane passing through the rotation axis of the blade where the blade is projected, the blade profile line located upstream of the fluid flow direction and from the hub to the rim is the blade inlet edge; the blade profile line located downstream of the fluid flow direction and from the hub to the rim is the blade outlet edge.

[0017] According to the blade design method for optimizing starting transient performance according to an embodiment of the present invention, the blade has a blade profile line. In a plane perpendicular to the rotation axis of the blade, the angle formed by the tangent direction at any point on the blade profile line and the circumferential direction is the blade setting angle. Among them, the angle formed by the tangent direction at the end point of the blade profile line located on the blade inlet edge and the circumferential direction is the inlet setting angle, and the difference between the inlet setting angle and the relative flow angle of the fluid flow at the blade inlet edge is the incidence angle.

[0018] According to the vane design method for optimizing starting transient performance according to an embodiment of the present invention, between the inlet edge and the outlet edge of the vane, multiple points can be equally spaced from the hub to the shroud; connecting the corresponding points on the inlet and outlet edges of the vane with a curve along the fluid flow direction can form multiple vane profiles.

[0019] A vane pump according to an embodiment of the present invention includes: a hub, a shroud, and vanes designed according to the vane design method for optimizing starting transient performance according to an embodiment of the present invention. The vanes are located between the outer peripheral surface of the hub and the inner peripheral surface of the shroud. The vanes are connected to the hub, and there is a gap between the vanes and the shroud to rotate relative to the shroud. Fluids are adapted to flow in the flow passage formed by the hub and the shroud.

[0020] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. Description of the Drawings

[0021] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the description of the embodiments in conjunction with the following drawings, where:

[0022] Figure 1 is an axial view of a vane pump according to an embodiment of the present invention;

[0023] Figure 2 is a front view of a vane pump according to an embodiment of the present invention along the rotation axis;

[0024] Figure 3 is a comparison chart of the change in transient flow rate during the starting process of a vane pump according to an embodiment of the present invention.

[0025] Reference Signs:

[0026] Vane pump 100,

[0027] Hub 10,

[0028] Shroud 20,

[0029] Vane 30, inlet edge 31 of the vane, outlet edge 32 of the vane, vane profile 33, first end 34 of the inlet edge of the vane, second end 35 of the inlet edge of the vane, any point 36 on the inlet edge of the vane, perpendicular distance 37 from the first end of the inlet edge of the vane to the rotation axis, inlet setting angle 38,

[0030] Fluid flow direction 40. Detailed Description of the Embodiments

[0031] Embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are only used to explain the present invention and should not be construed as a limitation of the present invention.

[0032] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention 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 thus should not be construed as a limitation of the present invention. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more.

[0033] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "mounted", "connected" and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0034] Next, refer to Figures 1 - 3 to describe a blade design method for optimizing startup transient performance according to an embodiment of the present invention.

[0035] The blade 30 has a blade inlet edge 31 and a blade outlet edge 32. Among them, in the prior art, the incidence angle of the blade 30 on the blade inlet edge 31 is usually the same, that is, the incidence angle of the first end 34 of the blade inlet edge 31 is the same as the incidence angle of the second end 35, and the incidence angle of any point between the first end 34 and the second end 35 is also the same as the incidence angle of the first end 34. In the prior art, no concept of designing the incidence angle sizes at various position points on the blade inlet edge 31 has been found or proposed. However, the applicant has found that by changing the incidence angle sizes of the blade 30 at different positions on the blade inlet edge 31, the startup transient performance can be improved.

[0036] Therefore, in the present invention, the applicant proposes a blade design method for optimizing the starting transient performance. The designed blade 30 has different angles of attack at any point 36 on the blade inlet edge 31, thereby reducing the inlet loss of the blade 30, optimizing the pressure distribution of the blade inlet edge 31 from the hub 10 to the rim 20, suppressing flow separation, increasing the stable flow rate at the end of starting, and improving the starting transient performance.

[0037] According to the blade design method for optimizing the starting transient performance of an embodiment of the present invention, by designing the angle of attack on the blade inlet edge 31, the inlet loss of the blade 30 can be effectively reduced, flow separation can be suppressed, the starting transient performance can be improved, the effects of flow separation, rotating stall, etc. are improved, and problems such as flow regime deterioration and performance degradation are avoided.

[0038] Furthermore, the applicant obtained through experimental analysis that the magnitude Δβ of the angle of attack at different positions is related to the ratio x / L of the length x of the position from the end of the blade inlet edge 31 to the length L of the blade inlet edge 31. Specifically, the magnitude Δβ of the angle of attack satisfies the distribution law of a cubic function with x / L. By setting the distribution law of the cubic function, the inlet loss of the blade 30 can be reduced, the stable flow rate at the end of starting can be increased, the pressure distribution of the blade inlet edge 31 from the hub 10 to the rim 20 can be optimized, flow separation can be suppressed, and the starting transient performance can be improved.

[0039] According to some specific embodiments of the present invention, the magnitude of the angle of attack at any point 36 on the blade inlet edge 31 satisfies:

[0040]

[0041] wherein, Δβ(x) is the magnitude of the angle of attack at any point 36 on the blade inlet edge 31, L is the length of the blade inlet edge 31, that is, the distance between the first end 34 and the second end 35 of the blade inlet edge 31; x is the length from any point 36 on the blade inlet edge 31 to the first end 34 of the blade inlet edge 31, the first end 34 is the connection end of the blade inlet edge 31 and the hub 10, and the second end 35 is the end of the blade inlet edge 31 adjacent to the rim 20.

[0042] By making the angle of attack on the blade inlet edge 31 satisfy the above relationship, the inlet loss of the blade 30 can be effectively reduced, the pressure distribution of the blade inlet edge 31 from the hub 10 to the rim 20 can be optimized, thereby suppressing flow separation, increasing the flow rate growth rate, increasing the stable flow rate at the end of starting, improving the starting transient performance, and realizing the optimization of the starting transient performance.

[0043] Such as Figures 1 - 3As shown, a vane pump 100 according to an embodiment of the present invention includes: a hub 10, a rim 20, and vanes 30. The rim 20 is located outside the hub 10. Fluid is adapted to flow in the flow passage formed by the hub 10 and the rim 20. The hub 10 and the rim 20 are the inner and outer boundaries of the fluid flow passage. The vanes 30 are located between the outer peripheral surface of the hub 10 and the inner peripheral surface of the rim 20. The vanes 30 are connected to the outer peripheral surface of the hub 10. Here, the connection can be a fixed connection or a detachable connection. There is a gap between the vanes 30 and the inner peripheral surface of the rim 20. The vanes 30 can rotate relative to the rim 20. The vanes 30 rotate around their rotation axis to do work on the fluid. Among them, the vanes 30 are designed by the vane design method for optimizing the starting transient performance described above.

[0044] As Figure 1 and Figure 2 shown, the hub 10 and the rim 20 are projected onto a plane passing through the rotation axis of the vane pump 100 to form an axial flow passage. The vanes 30 are on the middle streamline of the axial flow passage and extend along the fluid flow direction.

[0045] As Figure 1 and Figure 2 shown, the vanes 30 have vane profiles 33. In a plane perpendicular to the rotation axis of the vanes 30, the angle formed by the tangent direction at any point 36 on the vane profile 33 and the circumferential direction is the vane setting angle, that is, the angle between the vane profile tangent and the circumferential velocity. Here, the angle is an acute angle. The angle formed by the tangent direction at the end point of the vane profile 33 located on the vane inlet edge 31 and the circumferential direction is the inlet setting angle 38. Among them, the difference between the inlet setting angle 38 and the relative flow angle of the fluid flow at the vane inlet is the incidence angle.

[0046] As Figure 1 shown, from the hub 10 to the rim 20, a plurality of points can be equally spaced on the vane inlet edge 31 and the vane outlet edge 32; a plurality of vane profiles 33 can be formed by connecting the corresponding points on the vane inlet edge 31 and the vane outlet edge 32 with a curve along the fluid flow direction 40.

[0047] As Figure 1 and Figure 2 shown, at the first end 34 of the vane inlet edge 31, that is, near the hub 10, the angle formed by the tangent direction of the vane profile 33 and the circumferential direction is the inlet setting angle 38 at the first end 34. The inlet setting angle 38 at other points of the vane profile and even at any point 36 on the vane inlet edge 31 can be defined accordingly. According to the fluid machinery flow principle, subtracting the relative flow angle of the fluid flow from the inlet setting angle 38 is the incidence angle.

[0048] As Figure 1As shown in the figure, on the plane where the blade 30 is projected and passing through the rotation axis of the blade 30, the contour line of the blade 30 from the hub 10 to the rim 20, which is located upstream of the fluid flow direction 40, is the blade inlet edge 31; the contour line of the blade 30 from the hub 10 to the rim 20, which is located downstream of the fluid flow direction 40, is the blade outlet edge 32.

[0049] As Figure 2 shown, the vane pump 100 has a plurality of vanes 30, and the plurality of vanes 30 are arranged staggeredly along the circumferential direction of the hub 10, that is, in the front view of the vane pump 100 along the rotation axis, as Figure 2 shown, a part of two adjacent vanes 30 overlaps in the projection on the plane perpendicular to the rotation axis.

[0050] Of course, the projections of two adjacent vanes 30 on the plane perpendicular to the rotation axis do not overlap, and the plurality of vanes 30 are arranged completely spaced apart.

[0051] As Figure 3 shown, the figure discloses a comparison of the transient flow rate changes during the start-up process of the vane pump 100 before and after the optimization design. Among them, the prototype pump is a vane pump with a 10° positive incidence angle superimposed on the inlet edge, and the optimized pump is the vane pump of the embodiment of the present invention. From Figure 3 this, it can be seen that in the initial stage of start-up, both the prototype pump and the optimized pump gradually increase the rotational speed to 1000 rpm within 0.2 seconds, and then maintain the rotational speed of 1000 rpm. At 0.5 seconds, the flow rate of the optimized pump can significantly exceed the flow rate of the prototype pump. At 1.2 seconds, the flow rate of the optimized pump has increased to 40 kg / s, the flow rate rising rate is fast, and the flow rate can be maintained stably, significantly exceeding the stable flow rate value of the prototype pump. After the start-up ends, the stable flow rate of the optimized pump is greater than the stable flow rate of the prototype pump. Obviously, the vane pump 100 according to the present invention can increase the stable flow rate at the end of start-up, reduce the flow loss, improve the start-up transient performance, and meet the expected effect.

[0052] It can be understood that after determining the flow channel shape of the vane pump 100, the positions of the blade inlet edge 31, the blade outlet edge 32, and the inclination angle of the blade 30, as well as design parameters such as the rated flow rate, rated head, and rated rotational speed, etc., the relative liquid flow angles at the inlet and outlet of the vane pump 100 can be calculated according to the fluid machinery flow principle and design theory, and the actual inlet setting angle 38 of the blade 30 can be given according to the distribution of Δβ(x). By using the common blade inlet and outlet circulation change rules, the blade profile under the set incidence angle can be obtained.

[0053] In different coordinate systems, x and L can be transformed into different expressions. In some examples, in the axial plane coordinate system z-r, the z-axis is the axis where the rotation axis is located, and the positive direction of the z-axis is the opposite direction of the rotation direction of the vane pump 100. z is the coordinate of any point 36 on the vane inlet edge on the z-axis, and r is the perpendicular distance from any point 36 on the vane inlet edge to the rotation axis. The length L of the vane inlet edge 31 and the length x from any point 36 on the vane inlet edge 31 to the first end 34 of the vane inlet edge 31 satisfy:

[0054]

[0055] Among them, r0 is the perpendicular distance 37 from the first end 34 to the rotation axis, r1 is the perpendicular distance from the second end 35 of the vane inlet edge 31 to the rotation axis, z0 is the coordinate of the first end 34 on the z-axis, and z1 is the coordinate of the second end 35 on the z-axis.

[0056] According to some embodiments of the present invention, the connection end of the vane inlet edge 31 and the hub 10 is the first end 34, and the end of the vane inlet edge 31 adjacent to the rim 20 is the second end 35. The magnitude of the incidence angle gradually increases from the first end 34 to the second end 35. Among them, the difference between the inlet setting angle 38 and the relative flow angle of the fluid flow at the inlet of the vane 30 is negative. At the position close to the first end 34, the difference between the inlet setting angle 38 and the relative flow angle is large, and at the position close to the second end 35, the difference between the inlet setting angle 38 and the relative flow angle is small.

[0057] As Figure 1 shown, according to some embodiments of the present invention, the value of the incidence angle at the connection end of the vane inlet edge 31 and the hub 10 is less than zero, that is, at the first end 34 of the vane inlet edge 31, the inlet setting angle 38 is less than the relative flow angle of the fluid flow at the inlet of the vane 30, so as to reduce the vane inlet loss at the first end 34.

[0058] According to some embodiments of the present invention, the value of the incidence angle at the end of the vane inlet edge 31 adjacent to the rim 20 is zero, that is, at the second end 35 of the vane inlet edge 31, the inlet setting angle 38 is equal to the relative flow angle of the fluid flow at the inlet of the vane 30, thereby reducing the vane inlet loss at the second end 35.

[0059] Of course, the value of the incidence angle at the end of the vane inlet edge 31 adjacent to the rim 20 can also be slightly greater than zero, that is, at the second end 35 of the vane inlet edge 31, the inlet setting angle 38 is slightly greater than the relative flow angle of the fluid flow at the vane inlet edge.

[0060] Other components and operations of the vane pump 100 according to the embodiments of the present invention are known to those of ordinary skill in the art and will not be described in detail here. Among them, the up-down direction, left-right direction, and front-back direction are based on the up-down direction, left-right direction, and front-back direction shown in the figure.

[0061] In the description of the present invention, unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature may include direct contact between the first and second features, or may include indirect contact between the first and second features through additional features therebetween. Moreover, the first feature being "above", "over" and "on" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the horizontal height of the first feature is higher than that of the second feature.

[0062] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0063] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A blade design method for optimizing startup transient performance, characterized in that, The blade has a blade inlet edge and a blade outlet edge, and the blade is configured such that the magnitudes of the angles of attack at any point on the blade inlet edge are different; The magnitude of the angle of attack at any point on the blade inlet edge satisfies a cubic function distribution law with respect to the ratio of the length from this point to the end of the blade inlet edge and the length of the blade inlet edge; The magnitude of the angle of attack at any point on the blade inlet edge satisfies: where Δβ(x) is the magnitude of the angle of attack at any point on the blade inlet edge, L is the length of the blade inlet edge, x is the length from any point on the blade inlet edge to the first end of the blade inlet edge, and the first end is the connection end of the blade inlet edge and the hub.

2. The blade design method for optimizing starting transient performance according to claim 1, characterized in that, In the axial plane coordinate system z-r, the z-axis is the axis where the blade rotation axis is located, z is the coordinate of any point on the blade inlet edge on the z-axis, r is the perpendicular distance from any point on the blade inlet edge to the rotation axis, and the length L of the blade inlet edge and the length x from any point on the blade inlet edge to the first end of the blade inlet edge satisfy: ， ， where r0 is the perpendicular distance from the first end to the rotation axis, r1 is the perpendicular distance from the second end of the blade inlet edge to the rotation axis, z0 is the coordinate of the first end on the z-axis, and z1 is the coordinate of the second end on the z-axis.

3. The blade design method for optimizing startup transient performance according to claim 1, wherein The blade is disposed between the hub and the rim. The blade is connected to the hub, and there is a gap between the blade and the rim for the blade to rotate relative to the rim. The connection end of the blade inlet edge and the hub is the first end, and the end of the blade inlet edge adjacent to the rim is the second end. The magnitude of the angle of attack gradually increases from the first end to the second end.

4. The blade design method for optimizing startup transient performance according to claim 3, wherein The value of the angle of attack at the connection end of the blade inlet edge and the hub is less than zero, and the value of the angle of attack at the end of the blade inlet edge adjacent to the rim is zero.

5. The blade design method for optimizing startup transient performance according to claim 1, characterized in that, The blade is disposed between the hub and the rim, and the fluid is adapted to flow in the flow passage formed by the hub and the rim. On the plane passing through the rotation axis of the blade where the blade is projected, the blade contour line located upstream of the fluid flow direction and from the hub to the rim is the blade inlet edge; the blade contour line located downstream of the fluid flow direction and from the hub to the rim is the blade outlet edge.

6. The blade design method for optimizing starting transient performance according to claim 5, characterized in that, The blade has a blade profile. In the plane perpendicular to the rotation axis of the blade, the angle formed by the tangent direction at any point on the blade profile and the circumferential direction is the blade setting angle. where the angle formed by the tangent direction at the end point of the blade profile located on the blade inlet edge and the circumferential direction is the inlet setting angle, and the difference between the inlet setting angle and the relative flow angle of the fluid flow at the blade inlet edge is the angle of attack at the blade inlet edge.

7. The blade design method for optimizing startup transient performance according to claim 6, characterized in that, Between the blade inlet edge and the blade outlet edge, a plurality of points are equally spaced from the hub to the rim; curves are used to connect the corresponding points on the blade inlet and outlet edges along the fluid flow direction to form a plurality of the blade profiles.

8. A vane pump, characterized in that, Including: A hub, a rim, and blades designed by the blade design method for optimizing starting transient performance according to any one of claims 1-7, the blades being located between the outer circumferential surface of the hub and the inner circumferential surface of the rim, the blades being connected to the hub, having a gap between the blades and the rim for rotating relative to the rim, and a fluid being adapted to flow in a flow passage formed by the hub and the rim.

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