Impeller design method and apparatus, storage medium

Abstract

This disclosure provides an impeller design method and apparatus, as well as a storage medium, relating to the field of mechanical equipment design. The impeller design method includes: determining the impeller flow channel of the axial flow pump and initial parameters of a two-dimensional airfoil matching the impeller flow channel based on the design objectives of the axial flow pump; generating two-dimensional blade ribs using the initial parameters of the two-dimensional airfoil and the inlet and outlet velocity triangles of the blade; adding a first control point between the blade root and the blade tip at the blade inlet edge to determine the shape of the blade inlet edge, and adding a second control point between the blade root and the blade tip at the blade outlet edge to determine the shape of the blade outlet edge; superimposing the blade thickness distribution information onto the blade ribs to obtain two-dimensional profiles of each blade cross-section; and performing coordinate transformation on the two-dimensional profiles of each blade cross-section to obtain three-dimensional blade coordinates for each cross-section, thereby obtaining a three-dimensional model of the blade.

Description

Technical Field

[0001] This disclosure relates to the field of mechanical equipment design, and in particular to an impeller design method and apparatus, and a storage medium. Background Technology

[0002] Axial flow pumps, characterized by large flow rate, energy efficiency, and relatively low head, are widely used in municipal water supply and drainage, agricultural irrigation, and water diversion projects. The impeller of an axial flow pump is the core flow-through component affecting its performance; its design directly determines the pump's performance.

[0003] For the design of axial flow pump impellers, due to the limited ability to express the geometry of spatially curved and torsional impellers, fixed airfoils are currently mainly used for blade design. For example, in the axial flow pump impeller design method based on Jukovsky airfoils, the axial flow pump impeller is designed by utilizing parameters such as blade cascade density, axial surface velocity and rotational velocity component, blade chord angle, airfoil camber, and thickness. Summary of the Invention

[0004] The inventors noted that in related technologies, blades are designed using fixed airfoils and then placed in the impeller flow channel at a certain angle. This method only quantifies some design parameters, resulting in insufficient blade geometric diversity and making it difficult to obtain the optimal solution when optimizing the design of axial flow pump impellers.

[0005] Accordingly, this disclosure provides an impeller design scheme that directly designs the blade shape based on the control points of the blade shape, thereby obtaining the optimal scheme when optimizing the design of the axial flow pump impeller.

[0006] According to a first aspect of the present disclosure, an impeller design method is provided, executed by an impeller design device, comprising: determining the impeller flow channel of the axial flow pump and initial parameters of a two-dimensional airfoil matching the impeller flow channel based on the design objectives of the axial flow pump; generating a two-dimensional blade rib line using the initial parameters of the two-dimensional airfoil and the blade inlet and outlet velocity triangles; adding a first control point between the blade root and the blade tip at the blade inlet edge to determine the shape of the blade inlet edge, and adding a second control point between the blade root and the blade tip at the blade outlet edge to determine the shape of the blade outlet edge; superimposing the thickness distribution information of the blade onto the blade rib line to obtain two-dimensional profiles of each cross-section of the blade; and performing coordinate transformation on the two-dimensional profiles of each cross-section of the blade to obtain three-dimensional blade coordinates of each cross-section of the blade, thereby obtaining a three-dimensional model of the blade.

[0007] In some embodiments, generating a two-dimensional blade skeleton line using the initial parameters of the two-dimensional airfoil and the blade inlet and outlet velocity triangles includes: determining the blade and the diameter D based on the initial parameters of the two-dimensional airfoil. jThe coordinates Pi of the i-th point on the intersection line of the cross section in the three-dimensional cylindrical coordinate system, where the diameter is D. j The cross section is the j-th cross section from the hub to the rim, 1≤j≤n, where n is the total number of cross sections from the hub to the rim; a first tangent line of the initial two-dimensional airfoil bone line included in the initial parameters of the two-dimensional airfoil is generated at the inlet point of the blade, and a second tangent line of the initial two-dimensional airfoil bone line is generated at the outlet point of the blade; a first intermediate control point P1′(θ′1, m1′) is selected on the first tangent line, and a second intermediate control point P2′(θ′2, m2′) is selected on the second tangent line; a first control point matrix of the initial two-dimensional airfoil bone line is constructed using the first intermediate control point, the second intermediate control point, the first endpoint P1(θ1, m1) and the second endpoint P2(θ2, m2) of the blade; and a two-dimensional blade bone line is constructed using a preset curve based on the first control point matrix of the two-dimensional airfoil bone line.

[0008] In some embodiments, the blade has a diameter of D j The coordinates Pi of the i-th point on the intersection line of the cross section in the three-dimensional cylindrical coordinate system are:

[0009] Pi = (R i , (lx-x0)*sinβLi+(ly-y0)*cosβLi, θ i +θ0)

[0010] Where (lx, ly) are the initial two-dimensional airfoil rib coordinates, (x0, y0) are the blade inlet coordinates, θ0 is the angle of the blade inlet inlet in the three-dimensional cylindrical coordinate system, and R i θ is the radial distance of the i-th point. i Let βLi be the angle of the i-th point in the three-dimensional cylindrical coordinate system, and let βLi be the blade placement angle.

[0011] In some embodiments, the angle of the first tangent is β1i, and the angle of the second tangent is β2i; the first intermediate control point and the second intermediate control point satisfy:

[0012]

[0013]

[0014] In some embodiments, the first control point matrix is:

[0015]

[0016] In some embodiments, a preset number of K third intermediate control points Pk′(θ′) are set between the first intermediate control point and the second intermediate control point. k,mk′), where 1≤k≤K, and m1′≤mk′≤m2′; construct the second control point matrix of the initial two-dimensional airfoil rib line using the first intermediate control point, the second intermediate control point, the first end point and the second end point of the blade, and the preset number of third intermediate control points; construct the two-dimensional blade rib line using the preset curve based on the second control point matrix of the two-dimensional airfoil rib line.

[0017] In some embodiments, the second control point matrix is:

[0018]

[0019] In some embodiments, the preset curve is a Bézier curve.

[0020] In some embodiments, adding a first control point between the leaf root and the leaf tip of the blade inlet edge to determine the shape of the blade inlet edge includes: constructing a corresponding first parabola based on the leaf tip control point (R1, Z1, θ1), the leaf root control point (R3, Z3, θ3), and the first control point (R5, Z5, θ5); and using the first parabola to determine the shape of the blade inlet edge.

[0021] In some embodiments, the parameter θ5 of the first control point satisfies:

[0022]

[0023] In some embodiments, the first parabola is:

[0024] Z = f1(R) = a*R 2 +b*R+C

[0025] in,

[0026]

[0027]

[0028]

[0029] In some embodiments, adding a second control point between the leaf root and the leaf tip of the blade exit edge to determine the shape of the blade exit edge includes: constructing a corresponding second parabola based on the leaf tip control point (R2, Z2, θ2), the leaf root control point (R4, Z4, θ4), and the second control point (R6, Z6, θ6); and using the second parabola to determine the shape of the blade exit edge.

[0030] In some embodiments, the parameter θ6 of the second control point satisfies:

[0031]

[0032] In some embodiments, the second parabola is:

[0033] Z = f2(R) = a*R 2 +b*R+C

[0034] in,

[0035]

[0036]

[0037]

[0038] According to a second aspect of the present disclosure, an impeller design apparatus is provided, comprising: a first processing module configured to determine the impeller flow channel of the axial flow pump and initial parameters of a two-dimensional airfoil matching the impeller flow channel based on the axial flow pump design objectives; a second processing module configured to generate two-dimensional blade rib lines using the initial parameters of the two-dimensional airfoil and blade inlet / outlet velocity triangles; a third processing module configured to add a first control point between the blade root and the blade tip at the blade inlet edge to determine the shape of the blade inlet edge, and add a second control point between the blade root and the blade tip at the blade outlet edge to determine the shape of the blade outlet edge; a fourth processing module configured to superimpose the thickness distribution information of the blade onto the blade rib lines to obtain two-dimensional profiles of each cross-section of the blade; and a fifth processing module configured to perform coordinate transformation on the two-dimensional profiles of each cross-section of the blade to obtain three-dimensional blade coordinates of each cross-section of the blade, thereby obtaining a three-dimensional model of the blade.

[0039] According to a third aspect of the present disclosure, an impeller design apparatus is provided, comprising: a memory configured to store instructions; and a processor coupled to the memory, the processor being configured to execute instructions stored in the memory to implement the method as described in any of the above embodiments.

[0040] According to a fourth aspect of the present disclosure, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores computer instructions that, when executed by a processor, implement the method as described in any of the above embodiments.

[0041] Other features and advantages of this disclosure will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a flowchart illustrating an impeller design method according to an embodiment of the present disclosure;

[0044] Figure 2 This is a schematic diagram of the blade inlet and outlet velocity triangles according to an embodiment of this disclosure;

[0045] Figure 3 This is a schematic diagram of a two-dimensional deployable airfoil according to an embodiment of the present disclosure;

[0046] Figure 4 This is a schematic diagram of a two-dimensional bone line tangent according to an embodiment of the present disclosure;

[0047] Figure 5 This is a schematic diagram illustrating the control of the blade inlet edge shape and the blade outlet edge shape according to an embodiment of the present disclosure;

[0048] Figure 6 This is a schematic diagram of the three-dimensional shape of a blade according to an embodiment of the present disclosure;

[0049] Figure 7 This is a schematic diagram of the structure of an impeller design device according to an embodiment of the present disclosure;

[0050] Figure 8 This is a schematic diagram of the impeller design device according to another embodiment of the present disclosure. Detailed Implementation

[0051] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this disclosure or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0052] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of this disclosure.

[0053] At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn according to actual scale.

[0054] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0055] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0056] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0057] Figure 1 This is a schematic flowchart illustrating an impeller design method according to an embodiment of the present disclosure. In some embodiments, the following impeller design method is performed by an impeller design apparatus.

[0058] In step 101, the initial parameters of the impeller flow channel and the two-dimensional airfoil that match the impeller flow channel are determined according to the design objectives of the axial flow pump.

[0059] In some embodiments, the initial parameters of the two-dimensional airfoil include the blade chord length, the blade inlet and outlet angles, and the initial two-dimensional airfoil rib line.

[0060] In some embodiments, the target flow rate Q(m) of the axial flow pump is designed according to the requirements. 3 Calculate the specific speed using the impeller diameter D (mm) and impeller head H (m), and rotational speed n (r / min), determine the impeller diameter D (mm) and number of blades Z, and determine the hub ratio based on statistical data. The flow channel profile is determined using the above parameters, and the initial parameters of the two-dimensional airfoil for the axial flow pump are calculated based on this.

[0061] (1-1) Calculate the chord length

[0062] By hub ratio The hub diameter dh is calculated from the impeller diameter D.

[0063] Determine the blade density Itd and ItD at the hub and rim respectively using specific speed statistical data. Take n uniform cross-sections from the hub to the rim, with the diameter of the i-th cross-section being D. i The pitch is ti, the chord length is Li, and the chord length satisfies the following formula (1).

[0064]

[0065] Where Iti is the cascade density of the i-th cross section.

[0066] (1-2) Calculate the blade inlet / outlet angle and placement angle.

[0067] like Figure 2 As shown, for the velocity triangle at the blade inlet and outlet, the velocity is determined by the flow rate Q, impeller diameter D, hub diameter dh, and volumetric efficiency η. v Calculate the axial velocity ν m As shown in formula (2).

[0068] ν m =4Q / (π(D) 2 -dh 2 )*η v (2)

[0069] Based on the diameter D of the cross section where the blade is located i The rotational tangential velocity ui at the blade inlet is determined by the rotational speed n, as shown in formula (3).

[0070] ui=π*D i *n / 60 (3)

[0071] The head H and the diameter D of the blade section are determined by the head H and the diameter D of the blade section. i Rotational speed n and hydraulic efficiency η h Determine the exit rotational tangential velocity k u2 As shown in formula (4).

[0072]

[0073] From the inlet and outlet velocity triangles, the inlet angle β1i and outlet angle β2i of each cross section can be obtained, as shown in formula (5).

[0074]

[0075] The blade placement angle βLi = (β1i + β2i) / 2.

[0076] (1-3) Calculation of two-dimensional airfoil bone lines

[0077] After obtaining the chord length, blade inlet / outlet angle, and placement angle of the two-dimensional airfoil, the terminal point of the airfoil can be obtained from the chord length by giving the starting point of the airfoil. A curve is given between the starting point and the terminal point of the airfoil as the initial skelet line of the two-dimensional airfoil. The coordinates of this two-dimensional airfoil skelet line are expressed by (lx, ly), where lx and ly are two-dimensional arrays representing the two-dimensional airfoil skelet lines.

[0078] In step 102, two-dimensional blade skeleton lines are generated using the initial parameters of the two-dimensional airfoil and the inlet and outlet velocity triangles of the blade.

[0079] In some embodiments, step 102 above includes the following:

[0080] 1) Determine the blade and diameter D based on the initial parameters of the two-dimensional airfoil. j Let Pi be the coordinates of the i-th point Pi on the intersection line of the cross section in a three-dimensional cylindrical coordinate system, where the diameter is D. j The cross section is the j-th cross section from the hub to the rim, 1≤j≤n, where n is the total number of cross sections from the hub to the rim.

[0081] like Figure 3 As shown, the left figure is a three-dimensional airfoil, and the right figure is a two-dimensional deployed airfoil. At the blade tip section, the diameter is D, the blade chord length is L, the blade inlet point is P1, the outlet point is P2, the blade placement angle is βL, and the coordinates of the deployed two-dimensional airfoil are (lx, ly). The deployed two-dimensional airfoil is rotated by an angle βL around the blade inlet starting point P1 (x0, y0) to place the blade at the corresponding position in the three-dimensional coordinate system of the axial flow pump. After rotating by an angle βL, the coordinates of any point on the two-dimensional airfoil are shown in formula (6):

[0082]

[0083] Where x0 and y0 are the coordinates of the blade inlet starting point P1.

[0084] The rotated two-dimensional airfoil has the following relationship in the three-dimensional cylindrical coordinate system where the impeller is located:

[0085]

[0086] The angle θ that any point on the intersection line of the blade and the section with diameter D rotates through in the three-dimensional cylindrical coordinate system can be obtained from the above formula, as shown in formula (8).

[0087] θ=((lx-x0)*cosβL-(ly-y0)*sinβL) / R (8)

[0088] The angle of the blade inlet starting point in the three-dimensional cylindrical coordinate system is θ0, which is determined by the position of the given starting point P1 of the blade. In the three-dimensional Cartesian coordinate system where the impeller is located, the coordinates of any point on the xy plane on the intersection line of the blade and the section with diameter D can be shown in formula (9).

[0089]

[0090] Therefore, the blade and the diameter D j The coordinates Pi (X, Y, Z) of the i-th point on the intersection line of the cross section can be expressed in a three-dimensional Cartesian coordinate system as:

[0091] Pi = (R i *cos(θ0+θ i ), R i *sin(θ0+θ i), (lx-x0)*sinβLi+(ly-y0)*cosβLi) (10)

[0092] In a three-dimensional cylindrical coordinate system, the blade is parallel to a diameter D. j The coordinates Pi of the i-th point on the intersection line of the cross sections can be expressed as:

[0093] Pi = (R i , (lx-x0)*sinβLi+(ly-y0)*cosβLi, θ i +θ0) (11)

[0094] Where (lx, ly) are the initial two-dimensional airfoil rib coordinates, (x0, y0) are the blade inlet coordinates, θ0 is the angle of the blade inlet inlet in the three-dimensional cylindrical coordinate system, and R i Let θ be the radial distance to the i-th point. i Let βLi be the angle of the i-th point in the three-dimensional cylindrical coordinate system, and let βLi be the blade placement angle.

[0095] 2) Generate the first tangent of the initial two-dimensional airfoil bone line included in the initial parameters of the two-dimensional airfoil at the inlet point of the blade, and generate the second tangent of the initial two-dimensional airfoil bone line at the outlet point of the blade.

[0096] 3) Select the first intermediate control point P1′(θ′1,m1′) on the first tangent line, and select the second intermediate control point P2′(θ′2,m2′) on the second tangent line.

[0097] like Figure 4 As shown, straight lines with angles β1i and β2i are drawn at the blade inlet and outlet points, respectively, as tangents to the two-dimensional blade skeleton lines. Taking the first intermediate control point P1′(θ′1, m1′) and the second intermediate control point P2′(θ′2, m2′) on the blade inlet and outlet tangents, respectively, the following relationship exists:

[0098]

[0099] 4) Construct the first control point matrix of the initial two-dimensional airfoil bone line using the first intermediate control point, the second intermediate control point, the first endpoint P1(θ1, m1) and the second endpoint P2(θ2, m2) of the blade.

[0100] For example, the first control point matrix is ​​shown in formula (13):

[0101]

[0102] 5) Based on the first control point matrix of the two-dimensional airfoil rib line, construct the two-dimensional blade rib line using a preset curve.

[0103] For example, the preset curve is a Bézier curve.

[0104] In some embodiments, a preset number of K third intermediate control points Pk′(θ′) are set between the first intermediate control point and the second intermediate control point. k ,mk′), where 1≤k≤K, and m1′≤mk′≤m2′.

[0105] Next, the second control point matrix of the initial two-dimensional airfoil bone line is constructed using the first intermediate control point, the second intermediate control point, the first and second endpoints of the blade, and a preset number of third intermediate control points.

[0106] In some embodiments, the second control point matrix is ​​as shown in formula (14).

[0107]

[0108] Next, based on the second control point matrix of the two-dimensional airfoil rib line, the two-dimensional blade rib line is constructed using a preset curve.

[0109] For example, the preset curve is a third-order Bézier curve.

[0110] It should be noted that when the two-dimensional blade rib line constructed by Bézier curve is used to replace the initially given blade rib line, the impact loss is small and the hydraulic performance is better because the chord length, inlet and outlet angles, and placement angle of the two-dimensional blade rib line are consistent with the theoretical calculations.

[0111] In step 103, a first control point is added between the leaf root and the leaf tip of the blade inlet side to determine the shape of the blade inlet side, and a second control point is added between the leaf root and the leaf tip of the blade outlet side to determine the shape of the blade outlet side.

[0112] In some embodiments, such as Figure 5 As shown, a first control point P5 (R5, Z5, θ5) is added at the blade inlet edge in the direction from the blade root to the blade tip. Based on the blade tip control point (R1, Z1, θ1), the blade root control point (R3, Z3, θ3), and the first control point (R5, Z5, θ5) at the blade inlet edge, a corresponding first parabola is constructed, and then the shape of the blade inlet edge is determined using the first parabola.

[0113] In some embodiments, the parameter θ5 of the first control point satisfies:

[0114]

[0115] In some embodiments, the first parabola is:

[0116] Z = f1(R) = a*R 2 +b*R+C (16)

[0117] in,

[0118]

[0119]

[0120]

[0121] In some embodiments, such as Figure 5 As shown, a second control point P6 (R6, Z6, θ6) is added at the blade exit edge in the direction from the blade root to the blade tip. Based on the blade tip control point (R2, Z2, θ2), the blade root control point (R4, Z4, θ4), and the first control point (R6, Z6, θ6) at the blade exit edge, a corresponding second parabola is constructed, and then the shape of the blade inlet edge is determined using the second parabola.

[0122] In some embodiments, the parameter θ6 of the second control point satisfies:

[0123]

[0124] In some embodiments, the second parabola is:

[0125] Z = f2(R) = a*R 2 +b*R+C (21)

[0126] in,

[0127]

[0128]

[0129]

[0130] In step 104, the thickness distribution information of the blade is superimposed on the blade skeleton line to obtain the two-dimensional profile of each section of the blade.

[0131] In step 105, the two-dimensional profiles of each section of the blade are transformed to obtain the three-dimensional blade coordinates of each section, thereby obtaining the three-dimensional model of the blade.

[0132] like Figure 6 As shown, the three-dimensional shape of the blade designed through the above embodiments can be determined by the blade endpoint, the two-dimensional line control points of each cross section, and the blade inlet and outlet edge shape control points. By adjusting the angular coordinates and position coordinates of the control points, the blade flow surface coverage, blade curvature, relative position, etc. can be adjusted. The adjustment of the blade profile shape is intuitive, convenient, and highly flexible, and can obtain the optimal solution for the axial flow pump impeller optimization design.

[0133] Figure 7 This is a schematic diagram of the impeller design device according to an embodiment of the present disclosure. Figure 7 As shown, the impeller design device includes a first processing module 71, a second processing module 72, a third processing module 73, a fourth processing module 74, and a fifth processing module 75.

[0134] The first processing module 71 is configured to determine the impeller flow path of the axial flow pump and the initial parameters of the two-dimensional airfoil that match the impeller flow path, based on the design objectives of the axial flow pump.

[0135] In some embodiments, the initial parameters of the two-dimensional airfoil include the blade chord length, the blade inlet and outlet angles, and the initial two-dimensional airfoil rib line.

[0136] The second processing module 72 is configured to generate two-dimensional blade skeleton lines using the initial parameters of the two-dimensional airfoil and the blade inlet and outlet velocity triangles.

[0137] In some embodiments, the second processing module 72 determines the blade and the diameter D based on the initial parameters of the two-dimensional airfoil. j Let Pi be the coordinates of the i-th point Pi on the intersection line of the cross section in a three-dimensional cylindrical coordinate system, where the diameter is D. j The cross section is the j-th cross section from the hub to the rim, 1≤j≤n, where n is the total number of cross sections from the hub to the rim.

[0138] For example, the blade with a diameter of D j The coordinates of the i-th point Pi on the intersection line of the cross section in the three-dimensional cylindrical coordinate system are shown in the above formula (11).

[0139] Next, the second processing module 72 generates a first tangent line of the initial two-dimensional airfoil skeletal line included in the initial parameters of the two-dimensional airfoil at the blade inlet point, and generates a second tangent line of the initial two-dimensional airfoil skeletal line at the blade outlet point. A first intermediate control point P1′(θ′1, m1′) is selected on the first tangent line, and a second intermediate control point P2′(θ′2, m2′) is selected on the second tangent line.

[0140] For example, the angle of the first tangent is β1i, and the angle of the second tangent is β2i. The first intermediate control point and the second intermediate control point satisfy the above formula (12).

[0141] Next, the second processing module 72 constructs a first control point matrix for the initial two-dimensional airfoil rib line using the first intermediate control point, the second intermediate control point, the first endpoint P1(θ1, m1) and the second endpoint P2(θ2, m2) of the blade. Based on the first control point matrix of the two-dimensional airfoil rib line, the second processing module 72 constructs the two-dimensional blade rib line using a preset curve.

[0142] For example, the first control point matrix is ​​shown in formula (13) above.

[0143] For example, the preset curve is a Bézier curve.

[0144] In some embodiments, the second processing module 72 sets a preset number K third intermediate control points Pk′(θ′) between the first intermediate control point and the second intermediate control point. k ,mk′), where 1≤k≤K, and m1′≤mk′≤m2′.

[0145] The second processing module 72 constructs a second control point matrix for the initial two-dimensional airfoil rib line using the first intermediate control point, the second intermediate control point, the first end point and the second end point of the blade, and a preset number of third intermediate control points, and constructs the two-dimensional blade rib line using a preset curve based on the second control point matrix of the two-dimensional airfoil rib line.

[0146] For example, the second control point matrix is ​​shown in formula (14) above.

[0147] For example, the preset curve is a third-order Bézier curve.

[0148] The third processing module 73 is configured to add a first control point between the blade root and the blade tip of the blade inlet side to determine the shape of the blade inlet side, and to add a second control point between the blade root and the blade tip of the blade outlet side to determine the shape of the blade outlet side.

[0149] In some embodiments, the third processing module 73 constructs a corresponding first parabola based on the blade tip control point (R1, Z1, θ1), the blade root control point (R3, Z3, θ3), and the first control point (R5, Z5, θ5) of the blade inlet edge, and uses the first parabola to determine the shape of the blade inlet edge.

[0150] For example, the parameter θ5 of the first control point satisfies the condition of the above formula (15).

[0151] For example, the first parabola is shown in the above formula (16).

[0152] In some embodiments, the third processing module 73 constructs a corresponding second parabola based on the blade tip control point (R2, Z2, θ2), the blade root control point (R4, Z4, θ4), and the second control point (R6, Z6, θ6) of the blade exit edge, and uses the second parabola to determine the shape of the blade exit edge.

[0153] For example, the parameter θ6 of the second control point satisfies the condition of the above formula (20).

[0154] For example, the second parabola is shown in the above formula (21).

[0155] The fourth processing module 74 is configured to superimpose the thickness distribution information of the blade onto the blade skeleton line to obtain the two-dimensional profile of each section of the blade.

[0156] The fifth processing module 75 is configured to perform coordinate transformation on the two-dimensional profiles of each section of the blade to obtain the three-dimensional blade coordinates of each section of the blade, thereby obtaining the three-dimensional model of the blade.

[0157] Figure 8 This is a schematic diagram of the impeller design device according to another embodiment of this disclosure. Figure 8 As shown, the impeller design device includes a memory 81 and a processor 82.

[0158] Memory 81 is used to store instructions. Processor 82 is coupled to memory 81 and is configured to execute instructions based on the memory storage, as shown in the example below. Figure 1 The method involved in any of the embodiments.

[0159] like Figure 8 As shown, the impeller design device also includes a communication interface 83 for exchanging information with other devices. Additionally, the impeller design device includes a bus 84, through which the processor 82, communication interface 83, and memory 81 communicate with each other.

[0160] The memory 81 may include high-speed RAM, and may also include non-volatile memory, such as at least one disk drive. The memory 81 may also be a memory array. The memory 81 may also be divided into blocks, and these blocks may be combined into virtual volumes according to certain rules.

[0161] Furthermore, processor 82 may be a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement embodiments of the present disclosure.

[0162] This disclosure also relates to a computer-readable storage medium storing computer instructions that, when executed by a processor, implement... Figure 1 The method involved in any of the embodiments.

[0163] By implementing the above embodiments of this disclosure, the following beneficial effects can be obtained:

[0164] 1) This disclosure uses velocity triangle analysis to determine the blade inlet and outlet angles when the impact loss is minimized, and establishes the relationship between blade geometry and blade characteristic parameters through direct mathematical modeling of the blade, which can obtain a base model with better performance.

[0165] 2) In this disclosure, the blade shape is directly controlled by the endpoints, two-dimensional profile control points, and inlet / outlet edge shape control points. The adjustment is intuitive, convenient, and highly flexible, with rich geometric designs that facilitate optimization. The shape design of the blade inlet / outlet edges can adjust the forward and backward sweep of the blade, achieving the purpose of blade modification and improving cavitation damage at the tip of the high-speed rotating impeller.

[0166] In some embodiments, the functional units described above may be implemented as general-purpose processors, programmable logic controllers (PLCs), digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or any suitable combination thereof for performing the functions described herein.

[0167] Those skilled in the art will understand that all or part of the steps of the above embodiments can be implemented by hardware or by a program instructing related hardware. The program can be stored in a computer-readable storage medium, such as a read-only memory, a disk, or an optical disk.

[0168] The description in this disclosure is provided for illustrative and descriptive purposes only and is not intended to be exhaustive or to limit the disclosure to its forms. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described in order to better illustrate the principles and practical application of this disclosure and to enable those skilled in the art to understand this disclosure and to design various embodiments with various modifications suitable for a particular purpose.

Claims

1. An impeller design method, executed by an impeller design device, comprising: The initial parameters of the impeller flow channel and the two-dimensional airfoil that match the impeller flow channel are determined according to the design objectives of the axial flow pump. Two-dimensional blade skeleton lines are generated using the initial parameters of the two-dimensional airfoil and the inlet and outlet velocity triangles of the blade; A first control point is added between the leaf root and the leaf tip of the blade inlet side to determine the shape of the blade inlet side, and a second control point is added between the leaf root and the leaf tip of the blade outlet side to determine the shape of the blade outlet side. The thickness distribution information of the blade is superimposed on the blade skeleton line to obtain the two-dimensional profile of each cross section of the blade; The two-dimensional profiles of each section of the blade are transformed by coordinates to obtain the three-dimensional blade coordinates of each section of the blade, thereby obtaining the three-dimensional model of the blade. Specifically, adding a first control point between the leaf root and the leaf tip at the blade inlet edge to determine the shape of the blade inlet edge includes: According to the blade tip control point at the blade inlet edge ( , , The blade root control point at the blade inlet edge ( , , ) and the first control point ( , , Construct the corresponding first parabola, where the parameters of the first control point are... satisfy ; The shape of the blade inlet edge is determined using the first parabola.

2. The method according to claim 1, wherein, Generating two-dimensional blade skeleton lines using the initial parameters of the two-dimensional airfoil and the inlet and outlet velocity triangles of the blade includes: Based on the initial parameters of the two-dimensional airfoil, the blade and its diameter are determined. The first section on the intersection line Coordinates of points The coordinates in a three-dimensional cylindrical coordinate system, wherein the diameter is... The cross section is the first section from the hub to the rim. A cross section, , This represents the total number of cross sections from the hub to the rim. A first tangent line of the initial two-dimensional airfoil bone line, which is included in the initial parameters of the two-dimensional airfoil, is generated at the inlet point of the blade, and a second tangent line of the initial two-dimensional airfoil bone line is generated at the outlet point of the blade. Select a first intermediate control point on the first tangent line. Select a second intermediate control point on the second tangent line. ; Using the first intermediate control point, the second intermediate control point, and the first end point of the blade Second endpoint Construct the first control point matrix of the initial two-dimensional airfoil bone line; Based on the first control point matrix of the two-dimensional airfoil rib line, a two-dimensional blade rib line is constructed using a preset curve.

3. The method according to claim 2, wherein, The blade and its diameter are The first section on the intersection line Coordinates of points The coordinates in a three-dimensional cylindrical coordinate system are: in, Let the initial two-dimensional airfoil bone line coordinates be... The coordinates of the blade's starting point. Let be the angle of the blade inlet starting point in a three-dimensional cylindrical coordinate system. For the first The radial distance between points For the first The angle of a point in a three-dimensional cylindrical coordinate system The angle at which the blades are positioned.

4. The method according to claim 2, wherein, The angle of the first tangent is The angle of the second tangent is ; The first intermediate control point and the second intermediate control point satisfy the following:

5. The method according to claim 4, wherein, The first control point matrix is: 。 6. The method according to claim 2, further comprising: A preset number is set between the first intermediate control point and the second intermediate control point. A third intermediate control point ,in ,and ; The second control point matrix of the initial two-dimensional airfoil bone line is constructed using the first intermediate control point, the second intermediate control point, the first end point and the second end point of the blade, and the preset number of third intermediate control points. Based on the second control point matrix of the two-dimensional airfoil rib line, a two-dimensional blade rib line is constructed using a preset curve.

7. The method according to claim 6, wherein, The second control point matrix is: 。 8. The method according to claim 2, wherein, The preset curve is a Bézier curve.

9. The method according to claim 1, wherein, The first parabola is: in, - 。 10. The method according to claim 1, wherein, Adding a second control point between the leaf root and the leaf tip at the blade exit edge to determine the shape of the blade exit edge includes: According to the blade tip control point at the blade exit edge ( , , The leaf root control point at the exit edge of the blade ( , , ) and the second control point ( , , Construct the corresponding second parabola; The shape of the blade exit edge is determined using the second parabola.

11. The method according to claim 10, wherein, Parameters of the second control point satisfy: 。 12. The method according to claim 11, wherein, The second parabola is: in, - 。 13. An impeller design device, comprising: The first processing module is configured to determine the impeller flow path of the axial flow pump and the initial parameters of the two-dimensional airfoil that match the impeller flow path, based on the design objectives of the axial flow pump. The second processing module is configured to generate two-dimensional blade skeleton lines using the initial parameters of the two-dimensional airfoil and the blade inlet and outlet velocity triangles. The third processing module is configured to add a first control point between the blade root and the blade tip of the blade inlet side to determine the shape of the blade inlet side, and to add a second control point between the blade root and the blade tip of the blade outlet side to determine the shape of the blade outlet side, wherein the shape is determined based on the blade tip control point of the blade inlet side ( , , The blade root control point at the blade inlet edge ( , , ) and the first control point ( , , Construct the corresponding first parabola, where the parameters of the first control point are... satisfy The shape of the blade inlet edge is determined using the first parabola; The fourth processing module is configured to superimpose the thickness distribution information of the blade onto the blade skeleton line to obtain the two-dimensional profile of each cross section of the blade. The fifth processing module is configured to perform coordinate transformation on the two-dimensional profiles of each section of the blade to obtain the three-dimensional blade coordinates of each section of the blade, thereby obtaining the three-dimensional model of the blade.

14. An impeller design device, comprising: The memory is configured to store instructions; A processor, coupled to a memory, configured to implement the method as described in any one of claims 1-12 based on memory-stored instruction execution.

15. A non-transient computer-readable storage medium, wherein, A computer-readable storage medium stores computer instructions that, when executed by a processor, implement the method as described in any one of claims 1-12.

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