Geometric generation method for third-class relative flow surface S3 of vane pump

Abstract

The invention relates to a vane pump third-class relative flow surface S3 geometric generation method which comprises the following steps: respectively making M S1 flow surfaces and N S2 flow surfaces in a channel formed by two adjacent vanes; the first S1 flow surface is a rim surface, the Mth S1 flow surface is a hub surface, and a plurality of S1 flow surfaces in the middle divide the overflowing channel in an equal-volume mode in the spanwise direction; the first S2 flow surface is a blade bone surface of one of the two adjacent blades, the Nth S2 flow surface is a bone surface of the other blade, and a plurality of middle S2 flow surfaces equally divide an overflowing channel between the two blades in the circumferential direction; each S1 flow surface intersects with the S2 flow surface to form MN intersecting lines, and respectively constructing N blade-crossing curves and M spanwise curves of the S3 flow surface; n blade-crossing curves and M spanwise curves are sequentially mixed from two directions to form an S3 flow surface. The problem that the geometric high precision of a complex third-class relative flow surface S3 space torque curved surface of the vane pump is difficult to form is solved, the generation of the complex space curved surface S3 flow surface is realized, and a foundation is laid for secondary flow analysis of the vane pump.

Description

TECHNICAL FIELD

[0001] The application relates to the field of fluid machinery, in particular to a third-type relative flow surface S3 geometric generation method based on CAD software. BACKGROUND

[0002] In order to analyze and evaluate the complex secondary flow in a vane pump and other turbine machinery, the applicant previously proposed a third-type flow surface and a design method thereof for secondary flow analysis and evaluation of turbine machinery (ZL202111431766.1), which provides an effective tool for secondary flow analysis and evaluation. The two types of relative flow surfaces proposed by Professor Wu Zhonghua are S1 and S2 flow surfaces, the S1 flow surface is approximately a rotary surface, the S2 flow surface is approximately a vane surface, and the S3 flow surface is described conceptually, that is, the S3 surface is perpendicular to the S1 and S2 flow surfaces, the S1 and S2 series are sequentially formed in the turbine machinery, and the S3 surface is designed according to the perpendicular principle. The patent does not involve the specific design method of the S3 flow surface. The application provides an implementation method of the complex geometric configuration of the S3 flow surface based on the three-dimensional CAD software such as PROE or UG.

[0003] The S3 flow surface of a propeller pump is a complex spatial curved surface. At present, the basic characteristics of the S3 flow surface are defined, that is, the S3 flow surface is perpendicular to the S1 rotary flow surface and the S2 flow surface formed by the vane surface. According to the characteristics, it is difficult to form a high-precision S3 characteristic surface, which restricts the development of flow field analysis technology. SUMMARY

[0004] In view of the problem that the complex third-type relative flow surface S3 spatial torque curved surface of a vane pump is difficult to form with high precision, a third-type relative flow surface S3 geometric generation method of a vane pump is provided. The application can generate the third-type relative flow surface in the impeller and guide vane of the vane pump by using the three-dimensional CAD software such as PROE and UG, and lays a foundation for the secondary flow analysis of the vane pump.

[0005] The technical scheme of the application is as follows:

[0006] A third-type relative flow surface S3 geometric generation method of a vane pump comprises the following steps:

[0007] Step 1, in a channel formed by two adjacent vane, M S1 flow surfaces and N S2 flow surfaces are formed, M and N are greater than or equal to 5; the first S1 flow surface is a rim surface, the Mth S1 flow surface is a hub surface, and the S1 flow surfaces in the middle divide the flow passage along the development direction into equal volumes; the first S2 flow surface is a vane surface of one of the two adjacent vanes, the Nth S2 flow surface is a vane surface of the other vane, and the S2 flow surfaces in the middle divide the flow passage between the two vanes into equal parts along the circumferential direction.

[0008] Step 2, each S1 flow surface intersects with S2 flow surface to form MN intersection lines, and N strip cross-blade curves and M strip span curves of S3 flow surface are respectively constructed;

[0009] Step 3, N strip cross-blade curves and M strip span curves are sequentially mixed from two directions to form S3 flow surface.

[0010] Further, the construction of 5 strip cross-blade curves and 5 strip span curves of S3 flow surface in step 2 is as follows: the intersection line of the mth S1 flow surface and the nth S2 flow surface is L mn , and a vertical line is taken on the intersection line L mn , and another point on the vertical line is taken as a vertical line to the adjacent intersection line in the same direction, so that the two line segments of the same length are the same, the foot point is obtained, and the adjacent foot points in different directions are sequentially connected by the Bezier curve to construct N strip cross-blade curves and M strip span curves of S3 flow surface.

[0011] Further, step 2 is specifically implemented as follows:

[0012] Each S1 flow surface intersects with S2 flow surface to form MN intersection lines, and the intersection line of the first S1 flow surface and the first S2 flow surface is denoted as L 11 , and the intersection lines are sequentially denoted as L mn .

[0013] A point P11 is taken on L11, a vertical line passing through P11 and perpendicular to L11 is drawn on the first S1 flow surface, a point R11 is taken on the vertical line, a vertical line of L12 is drawn, the foot point is P12, and the lengths of the two vertical line segments P11-R11 and R11-P12 are equal, and P13, P14, P15… are sequentially drawn; the Bezier curve is used to connect the above P points to form the first cross-blade curve C11 of S3 flow surface;

[0014] On the first S2 flow surface, a vertical line passing through P11 and perpendicular to L11 is drawn, a point R21 is taken on the vertical line, a vertical line of L21 is drawn, the foot point is P21, and the lengths of the two vertical line segments P11-R21 and R21-P21 are equal, and P31, P41, P51… are sequentially drawn; the Bezier curve is used to connect the above P points to form the first span curve C21 of S3 flow surface;

[0015] On the second S1 flow surface, a vertical line passing through P21 and perpendicular to L21 is drawn, a point is taken on the vertical line, a vertical line of L22 is drawn, the foot point is P22, and the lengths of the two vertical line segments are equal, and P23, P24, P25… are sequentially drawn; the Bezier curve is used to connect the above P points to form the second cross-blade curve C12 of S3 flow surface;

[0016] The third, fourth, and Nth span-wise curves C13, C14, and C1M are sequentially made by analogy; meanwhile, the Mth span-wise curves C22, C23, C24, and C2N are sequentially made by using the Bezier curve along the span direction.

[0017] The S3 flow surface is formed by sequentially mixing the Nth span-wise curves and the Mth span-wise curves from two directions.

[0018] Further, the vane pump is a pump impeller with multiple vanes.

[0019] Further, the S1 flow surfaces are sequentially arranged from the rim to the hub.

[0020] Optionally, the three-dimensional software includes PROE, UG, and CAD.

[0021] Further, the rim surface is formed by rotating the blade tip meridian flow line around an axis for one turn.

[0022] Further, the hub surface is formed by rotating the blade root meridian flow line around an axis for one turn.

[0023] Further, the sequential mixing in step 3 can be completed by using the boundary mixing menu in the software.

[0024] Further, the S3 flow surface is orthogonal to the S1 flow surface and the S2 flow surface.

[0025] The present application has the following beneficial effects:

[0026] The present application provides a third-type relative flow surface S3 geometric generation method of a vane pump based on three-dimensional CAD software. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 A pump impeller diagram of the present application;

[0028] Figure 2 A rim, hub, and two adjacent vanes diagram of the present application;

[0029] Figure 3 A line frame diagram of five S1 flow surfaces from the rim to the hub of the present application;

[0030] Figure 4 A diagram of five S1 flow surfaces from the rim to the hub of the present application;

[0031] Figure 5 A diagram of the fourth S1 flow surface of the present application;

[0032] Figure 6 A diagram of the S2 flow surface of the present application;

[0033] Figure 7 This is a diagram of three S2 flow surfaces between two adjacent blades of the present invention;

[0034] Figure 8 This is a group diagram of the S1 and S2 flow surfaces of the present invention, excluding the rim;

[0035] Figure 9 This is a diagram of the C11 curve and its constituent points according to the present invention.

[0036] Figure 10 This is a diagram of the C21 curve and its constituent dots of the present invention;

[0037] Figure 11 The S3 flow surface diagram is formed by the spanwise and transverse curves of this invention. Detailed Implementation

[0038] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0039] This invention provides a high-precision method for generating complex S3 flow surface geometry based on the principle of points forming lines and lines forming surfaces, using 3D software such as PROE or UG. The following explanation uses PROE software as an example to illustrate the S3 flow surface generation method; the methods are similar for other software.

[0040] For pump impellers with multiple blades ( Figure 1 Within the channel formed by two adjacent blades, five S1 flow surfaces and five S2 flow surfaces are constructed respectively. Figure 3 and Figure 4 The first (in order from rim to hub) S1 flow surface is the rim surface (see rim surface). Figure 2 The fifth is the hub surface (formed by the blade tip meridional streamline rotating around the axis), and the middle three S1 flow surfaces divide the flow channel into equal volumes along the spanwise direction. Figure 3 and Figure 4 The first S2 flow surface is the blade rib surface of one of the two adjacent blades, the fifth S2 flow surface is the rib surface of the other blade, and the middle three S2 flow surfaces divide the flow channel between the two blades into equal circumferential (angular) sections. Figure 6 and Figure 7 (Note: The three middle sections are flow surfaces, which divide the channel equally.)

[0041] Each S1 flow surface intersects with the S2 flow surface to form 25 intersection lines. The intersection line between the first S1 flow surface and the first S2 flow surface is denoted as L. 11 The names of the intersection lines are derived sequentially, that is, the intersection line between the m-th S1 flow surface and the n-th S2 flow surface is L.mn .

[0042] In the first S1 flow surface, a perpendicular line is drawn through P11 and L11, a point R11 is taken on the perpendicular line, a perpendicular line of L12 is drawn, the foot of the perpendicular is P12, and the lengths of the two perpendicular line segments P11-R11 and R11-P12 are made equal, and P13, P14 and P15 are drawn in turn. The above five points are connected by a Bezier curve to form the first spanwise curve C11 of the S3 flow surface, as shown in Fig. 1. Figure 4 .

[0043] In the first S2 flow surface, a perpendicular line is drawn through P11 and L11, a point R21 is taken on the perpendicular line, a perpendicular line of L21 is drawn, the foot of the perpendicular is P21, and the lengths of the two perpendicular line segments P11-R21 and R21-P21 are made equal, and P31, P41 and P51 are drawn in turn. The above five points are connected by a Bezier curve to form the first spanwise curve C21 of the S3 flow surface, as shown in Fig. 1. Figure 5 .

[0044] In the second S1 flow surface, a perpendicular line is drawn through P21 and L21, a point is taken on the perpendicular line, a perpendicular line of L22 is drawn, the foot of the perpendicular is P22, and the lengths of the two perpendicular line segments are made equal, and P23, P24 and P25 are drawn in turn. The above five points are connected by a Bezier curve to form the second spanwise curve C12 of the S3 flow surface.

[0045] The third, fourth and fifth spanwise curves C13, C14 and C15 are drawn in turn by analogy. Meanwhile, the spanwise curves C22, C23, C24 and C25 are formed by connecting the nodes in order (the order is 1 to 5) by a Bezier curve in the spanwise direction.

[0046] The S3 flow surface is formed by mixing the five spanwise curves and the five spanwise curves in two directions in turn (the surface forming can be completed by using the boundary mixing menu in the software). Figure 11 .

[0047] The attached drawings take a single channel formed by two blades as an example, and the channels between other blades can be rotated in the circumferential direction by equal angles; in order to be clearly visible, the S1, S2 and S3 flow surfaces in the drawings are expressed by grid surfaces.

[0048] a) According to the geometry of the pump blade, a certain blade surface is drawn, which bisects the blade in thickness, and this surface is the first S2 flow surface; then four S2 flow surfaces are copied in the circumferential direction, and the angle distance between every adjacent two S2 flow surfaces is 360° / total number of pump blades / 4, and the last S2 flow surface falls on the adjacent blade. A set of five S2 flow surfaces is completed.

[0049] b) make a group of 5 S1 flow surfaces, each adjacent S1 flow surface encloses equal volume (5 meridian flow lines including hub and rim rotate one circle around the axis can be obtained), the first S1 flow surface is the rim surface, the fifth S1 flow surface is the hub surface, and the rest of the S1 flow surfaces are numbered in turn from the rim to the hub.

[0050] c) 5 S1 flow surfaces intersect with 5 S2 flow surfaces respectively to form 25 curves, the intersection line of the first S1 flow surface and the first S2 flow surface is recorded as L 11 , and the rest of the intersection lines are named in turn, that is, the intersection line of the mth S1 flow surface and the nth S2 flow surface is L mn .

[0051] d) take a point P11 on L11, draw a perpendicular line through P11 and L11 on the first S1 flow surface, take a point R11 on the perpendicular line, draw a perpendicular line of L12, the foot point is P12, and the lengths of the two perpendicular line segments are equal, and the points P13, P14 and P15 are drawn in turn on the curves L13, L14 and L15 respectively. Adopt the Bezier curve to connect the above five points to form the first transverse curve C11 of the S3 flow surface.

[0052] e) draw a perpendicular line through P11 and L11 on the first S2 flow surface, take a point R21 on the perpendicular line, draw a perpendicular line of L21, the foot point is P21, and the lengths of the two perpendicular line segments are equal, and the foot points P31, P41 and P51 are drawn in turn on the curves L31, L41 and L51 respectively. Adopt the Bezier curve to connect the above five points to form the first spanwise curve C21 of the S3 flow surface.

[0053] f) draw a perpendicular line through P21 and L21 on the second S1 flow surface, take a point R22 on the perpendicular line, draw a perpendicular line of L22, the foot point is P22, and the lengths of the two perpendicular line segments are equal, and the foot points P23, P24 and P25 are drawn in turn on the curves L23, L24 and L25 respectively. Adopt the Bezier curve to connect the above five points to form the second transverse curve C12 of the S3 flow surface.

[0054] g) the third, fourth and fifth transverse curves C13, C14 and C15 are drawn in turn according to the above steps. At the same time, the spanwise curves C22, C23, C24 and C25 are formed by connecting the nodes in order along the spanwise direction by using the Bezier curve.

[0055] The S3 flow surface geometry is formed by mixing 5 transverse curves and 5 spanwise curves in turn from two directions.

[0056] The application provides a complex spatial curved surface S3 flow surface geometry generation method, which ensures that the S3 flow surface is orthogonal to the S1 flow surface and the S2 flow surface.

[0057] The above embodiment only expresses one implementation of the present application, which is described in more detail and in more detail, but cannot be understood as limiting the scope of the patent. It should be noted that for ordinary skilled in the art, without departing from the concept of the present application, several modifications and improvements can be made, which are within the scope of the present application. Therefore, the scope of protection of the present application patent should be subject to the appended claims.

Claims

1. A method for generating the geometry of the third type of relative flow surface S3 of a vane pump, characterized in that, Includes the following steps: Step 1: Within the channel formed by two adjacent blades, construct M S1 flow surfaces and N S2 flow surfaces, where M and N ≥ 5. The first S1 flow surface is the rim surface, the Mth is the hub surface, and the intermediate S1 flow surfaces divide the flow channel into equal volumes along the spanwise direction. The first S2 flow surface is the blade rib surface of one of the two adjacent blades, the Nth S2 flow surface is the rib surface of the other blade, and the intermediate S2 flow surfaces divide the flow channel between the two blades into equal volumes along the circumference. Step 2: Each S1 flow surface intersects with the S2 flow surface to form MN intersection lines, and N cross-blade curves and M spanwise curves are constructed for the S3 flow surface respectively; Step 3: Combine N cross-blade curves and M spanwise curves sequentially from two directions to form the S3 flow surface.

2. The method for generating the third type of relative flow surface S3 geometry of a vane pump according to claim 1, characterized in that, The five trans-blade curves and five spanwise curves of the S3 flow surface in step 2 are constructed as follows: the intersection line of the m-th S1 flow surface and the n-th S2 flow surface is L. mn , successively at the intersection line L mn Draw a perpendicular line from any point on the top, and then draw another perpendicular line from that point to the adjacent intersection line in the same direction, so that the two line segments of the same length are identical, thus obtaining the foot of the perpendicular. Connect the adjacent feet of the perpendicular in different directions in sequence using Bezier curves to construct N cross-blade curves and M spanwise curves of the S3 flow surface.

3. The method for generating the third type of relative flow surface S3 geometry of a vane pump according to claim 1, characterized in that, Step 2 is implemented as follows: Each S1 flow surface intersects with the S2 flow surface to form MN intersection lines. The intersection line between the first S1 flow surface and the first S2 flow surface is denoted as L. 11 The names of the intersection lines are derived sequentially, that is, the intersection line between the m-th S1 flow surface and the n-th S2 flow surface is L. mn ; Take any point P11 on L11. On the first S1 flow surface, draw a perpendicular line through P11 and perpendicular to L11. Take a point R11 on the perpendicular line and draw a perpendicular line to L12 with the foot of the perpendicular at P12. Make the lengths of the two perpendicular line segments P11-R11 and R11-P12 equal. Continue in this manner to draw P13, P14, P15... Connect the above points P with a Bezier curve to form the first cross-blade curve C11 for constructing the S3 flow surface. On the first S2 flow surface, draw a perpendicular line through P11 and perpendicular to L11. Take a point R21 on the perpendicular line and draw a perpendicular line to L21 with the foot of the perpendicular at P21. Make the lengths of the two perpendicular line segments P11-R21 and R21-P21 equal. Continue in this way to draw P31, P41, P51... Connect the above points P with a Bézier curve to form the first spanwise curve C21 for constructing the S3 flow surface. On the second S1 flow surface, draw a perpendicular line through P21 and perpendicular to L21. Take a point on the perpendicular line and draw a perpendicular line to L22, with the foot of the perpendicular at P22. Make the two perpendicular line segments equal in length. Similarly, draw P23, P24, P25... Connect the above P points with a Bezier curve to form the second cross-blade curve C12 that constructs the S3 flow surface. Similarly, the third, fourth, and Nth cross-blade curves C13, C14...C1M are successively drawn; at the same time, Bézier curves are used in sequence to connect each node along the spanwise direction to form M spanwise curves C22, C23, C24...C2N; The S3 flow surface is formed by sequentially mixing N cross-blade curves and M spanwise curves from two directions.

4. The method for generating the third type of relative flow surface S3 geometry of a vane pump according to claim 1, characterized in that, A vane pump is a pump impeller with multiple blades.

5. The method for generating the third type of relative flow surface S3 geometry of a vane pump according to claim 1, characterized in that, S1 flow surfaces are arranged from the first to the Mth in order from the rim to the hub.

6. The method for generating the third type of relative flow surface S3 geometry of a vane pump according to claim 1, characterized in that, It is generated using 3D software, including PROE, UG, and CAD.

7. The method for generating the third type of relative flow surface S3 geometry of a vane pump according to claim 1, characterized in that, The rim surface is formed by rotating the meridional streamline of the blade tip around the axis once.

8. The method for generating the third type of relative flow surface S3 geometry of a vane pump according to claim 1, characterized in that, The hub surface and blade root meridional streamlines are formed by rotating around the axis once.

9. The method for generating the third type of relative flow surface S3 geometry of a vane pump according to claim 1, characterized in that, In step 3, the surface shaping can be completed by using the boundary blending menu in the software.

10. The method for generating the third type of relative flow surface S3 geometry of a vane pump according to claim 1, characterized in that, Ensure that the S3 flow surface is orthogonal to both the S1 and S2 flow surfaces.

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