Finite element modeling method for volute flow channel, computer equipment and storage medium

Abstract

The invention relates to the technical field of volute modeling, and discloses a volute flow channel finite element modeling method, computer equipment and a storage medium, and the volute flow channel finite element modeling method comprises the following steps: constructing a plurality of typical sections based on section parameters, and for a straight pipe section, determining a straight pipe section arc edge on the circumference of the straight pipe section; for the elbow section, determining a seat ring guide vane arc edge on the inner side of the elbow on the circumference of the elbow section based on a preset height; bending a pipe section arc edge on the arc long edge connected with the intersection point of the two seat rings based on the arc transition factor; connecting the corresponding section intersection points to construct a first curve; connecting the corresponding seat ring intersection points to construct a second curve; constructing a side wall surface based on the adjacent first curve and the section arc edge; constructing a seat ring surface based on the adjacent second curve and the seat ring arc edge; and constructing a volute runner grid based on the section arc edge, the first curve, the second curve, the side wall surface and the seat ring surface. According to the invention, the grid division efficiency can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of volute modeling, and in particular to a volute flow channel finite element modeling method, computer equipment and storage medium. Background Art

[0002] The underground powerhouse of a pumped storage power station has a complex structure. As the operating head and speed of the unit continue to increase, problems such as vibration of the powerhouse structure are becoming increasingly prominent. During the structural design stage, the finite element analysis method is generally used to perform dynamic simulation calculations of the underground powerhouse structure to clarify the rationality of the underground powerhouse structure design and effectively prevent excessive vibration of the powerhouse structure. The quality of meshing is a key factor affecting the accuracy of simulation calculations. During the modeling process of the underground powerhouse, the volute flow channel has a complex structure and a three-dimensional spatial curve shape, making meshing more difficult.

[0003] Currently, tetrahedral meshes are used for partitioning, which has strong adaptability to complex geometric shapes. However, for the dynamic calculation of underground powerhouse structures, tetrahedral meshes may not provide sufficient accuracy in stress concentration areas, affecting the reliability of simulation results. At the same time, the large number of tetrahedral mesh units can easily lead to increased calculation time and resource consumption, and low partitioning efficiency. Summary of the invention

[0004] In view of this, the present invention provides a finite element modeling method for a volute flow passage, a computer device and a storage medium to improve meshing efficiency.

[0005] In a first aspect, the present invention provides a finite element modeling method for a volute flow passage, the finite element modeling method for a volute flow passage comprising: constructing a plurality of typical sections based on the cross-sectional parameters of the volute flow passage, the typical sections comprising a straight pipe section and a curved pipe section; for a straight pipe section, constructing a circumference of the straight pipe section with the center of the section circle, evenly determining a first number of straight pipe section intersection points on the circumference of the straight pipe section, connecting the arc edges of adjacent straight pipe section intersection points, and constructing a first number of straight pipe section arc edges; for a curved pipe section, constructing a circumference of the curved pipe section with the center of the section circle, determining two seat ring intersection points on the inner side of the curved pipe of the circumference of the curved pipe section based on a preset height, connecting the short sides of the arc of the two seat ring intersection points, and constructing an arc edge of a seat ring guide vane; determining a long side of the arc connecting the two seat ring intersection points based on an arc transition factor Determine a first number of intersections of curved pipe sections, connect adjacent intersections of curved pipe sections, connect adjacent intersections of curved pipe sections and intersections of seat rings, and construct a first number of curved pipe section arc edges; for adjacent typical sections, connect corresponding intersections of sections to construct a first number of first curves; for adjacent curved pipe sections, connect corresponding seat ring intersections to construct two second curves; section intersections include straight pipe section intersections and curved pipe section intersections; construct side wall surfaces based on section arc edges connecting adjacent first curves and first curves; section arc edges include straight pipe section arc edges and curved pipe section arc edges; construct seat ring surfaces based on seat ring arc edges connecting adjacent second curves and second curves; construct volute flow channel mesh based on section arc edges, first curves, second curves, side wall surfaces and seat ring surfaces.

[0006] In this implementation, the straight pipe section and the curved pipe section are divided by constructing a typical section, and different meshes are performed on the straight pipe section and the curved pipe section respectively. For the straight pipe section, only a uniform side wall surface is constructed. For the curved pipe section, the influence of the seat ring guide vane on the side wall surface is considered, and the arc transition factor is used to construct a side wall surface different from the straight pipe section, which can ensure a smooth transition of the side wall surface and improve the mesh quality. Further considering that the seat ring guide vane further constructs the seat ring surface on the basis of constructing the side wall surface can improve the meshing efficiency, thereby improving the accuracy and reliability of the simulation calculation.

[0007] In an optional embodiment, constructing multiple typical sections based on the cross-sectional parameters of the volute flow passage includes: obtaining the cross-sectional parameters of the volute flow passage, the cross-sectional parameters including the distance between the center of the section circle and the center of the coordinate origin, the circumferential radius of the section, and the cross-sectional angle; determining multiple typical sections in the volute flow passage based on the cross-sectional parameters; naming the typical sections from straight pipe sections to curved pipe sections, in sequence as sections 0 to n, wherein section 0 is a straight pipe section, and sections 1 to n are curved pipe sections; for each typical section, constructing a local coordinate system with the direction of the line connecting the center of the section circle and the coordinate origin as the X-axis and the elevation direction of the volute flow passage as the Y-axis.

[0008] In this implementation, each typical section is constructed according to the cross-sectional parameters of the volute flow passage, and then a corresponding local coordinate system is constructed for each typical section, which can facilitate different analyses of different sections and improve the subsequent meshing efficiency.

[0009] In an optional implementation, for a straight tube section, a straight tube section circumference is constructed with the section center, a first number of straight tube section intersections are uniformly determined on the straight tube section circumference, and arc edges of adjacent straight tube section intersections are connected to construct a first number of straight tube section arc edges, including: for a straight tube section, a straight tube section circumference is constructed with the section center, and a first straight tube section intersection, a second straight tube section intersection, a third straight tube section intersection, and a fourth straight tube section intersection are uniformly determined in sequence in a counterclockwise direction along the X-axis. The intersection of straight tube sections; the arc edge connecting the first straight tube section intersection and the fourth straight tube section intersection is constructed to obtain the first straight tube section arc edge, the arc edge connecting the first straight tube section intersection and the second straight tube section intersection is constructed to obtain the second straight tube section arc edge, the arc edge connecting the second straight tube section intersection and the third straight tube section intersection is constructed to obtain the third straight tube section arc edge, the arc edge connecting the third straight tube section intersection and the fourth straight tube section intersection is constructed to obtain the fourth straight tube section arc edge.

[0010] In this implementation, for straight pipe sections, on the basis of uniformly constructing the intersection points of the straight pipe sections, the arc edges of the straight pipe sections are uniformly constructed, which can ensure that the curvature of each arc is the same and the arc curvature is not too large, thereby generating a high-quality mesh.

[0011] In an optional embodiment, for a curved pipe section, a circumference of the curved pipe section is constructed with the center of the section, two seat ring intersections are determined on the inner side of the curved pipe of the circumference of the curved pipe section based on a preset height, and the short sides of the arcs of the two seat ring intersections are connected to construct an arc edge of the seat ring, including: for the curved pipe section, a circumference of the curved pipe section is constructed with the center of the section, a first seat ring intersection is determined at a Y-axis height H / 2 on the inner side of the curved pipe of the circumference of the curved pipe section, and a second seat ring intersection is determined at a Y-axis height -H / 2 on the inner side of the curved pipe of the circumference of the curved pipe section; and the short sides of the arcs of the first seat ring intersection and the second seat ring intersection are connected to construct an arc edge of the seat ring.

[0012] In this implementation, the position of the seat ring guide vane in the curved pipe section is taken into consideration, the seat ring is located inside the curved pipe of the circumference of the Wannian section, the seat ring intersection is determined at a height of ±H / 2, and the seat ring arc edge is further determined. The seat ring guide vane can be located in the middle of the inner side of the curved pipe, and a higher quality mesh can be generated.

[0013] In an optional embodiment, based on the arc transition factor, a first number of intersection points of the curved pipe sections are determined on the long side of the arc connected by the two seat ring intersection points, and adjacent intersection points of the curved pipe sections are connected, and adjacent intersection points of the curved pipe sections and the seat ring intersection points are connected to construct a first number of curved pipe section arc edges, including: when the curved pipe section is 1 section, the circumference of the curved pipe section is constructed with the center of the section circle, and the first curved pipe section intersection point, the second curved pipe section intersection point, the third curved pipe section intersection point and the fourth curved pipe section are uniformly determined on the long side of the arc in the counterclockwise direction of the X-axis. The angles of the first bend section intersection, the second bend section intersection, the third bend section intersection and the fourth bend section intersection are the same as the angles of the first straight section intersection, the second straight section intersection, the third straight section intersection and the fourth straight section intersection; the arc edge between the first bend section intersection and the first seat ring intersection is used as the first bend connection arc edge, and the arc edge between the fourth bend section intersection and the second seat ring intersection is used as the second bend connection arc edge; when the bend section is 2 to n sections, based on the arc transition factor f i The first bend of section i is connected to the arc edge l i The first arc length of 1′ determines the first bend connecting the arc edge l of the i+1 section i+1 The length of the second arc of 1′ is: arc(l i+1 1′)=f i ×arc(l i 1′); where the arc transition factor f i Less than zero; based on the arc transition factor f i The second bend of section i is connected to the arc edge l i The third arc length of 2′ determines the arc edge l of the second elbow of section i+1 i+1 2′; determine the first bend section intersection based on the second arc length in the positive direction of the Y axis, determine the fourth bend section intersection based on the fourth arc length in the negative direction of the Y axis, and determine the second bend section intersection and the third bend section intersection based on the second straight section intersection and the third straight section focus; wherein, the angles of the second bend section intersection and the third bend section intersection are respectively the same as the angles of the second straight section intersection and the third straight section intersection; connect the arc edge of the first bend section intersection and the fourth bend section intersection to construct the first bend section arc edge, connect the arc edge of the first bend section intersection and the second bend section intersection to construct the second bend section arc edge, connect the arc edge of the second bend section intersection and the third bend section intersection to construct the third bend section arc edge, connect the arc edge of the third bend section intersection and the fourth bend section intersection to construct the fourth bend section arc edge.

[0014] In this implementation, the arc of the curved pipe segment is adjusted using the arc transition factor, which can ensure smooth transition of the curved pipe arc and further improve the mesh quality.

[0015] In an optional embodiment, a side wall surface is constructed based on adjacent first curves and arc edges of sections connected by the first curves, including: for sections 0 and 1, a first straight tube side wall surface is constructed based on adjacent first curves, arc edges of first straight tube sections and arc edges of first curved tube sections; a second straight tube side wall surface is constructed based on adjacent first curves, arc edges of second straight tube sections and arc edges of second curved tube sections; a third straight tube side wall surface is constructed based on adjacent first curves, arc edges of third straight tube sections and arc edges of third curved tube sections; a fourth straight tube side wall surface is constructed based on adjacent first curves, arc edges of fourth straight tube sections and arc edges of fourth curved tube sections; for sections 1 to n, a first curved tube side wall surface is constructed based on adjacent first curves and arc edges of first curved tube sections; a second curved tube side wall surface is constructed based on adjacent first curves and arc edges of second curved tube sections; a third curved tube side wall surface is constructed based on adjacent first curves and arc edges of third curved tube sections; a fourth curved tube side wall surface is constructed based on adjacent first curves and arc edges of fourth curved tube sections.

[0016] In an optional embodiment, a seat ring surface is constructed based on an arc edge of the seat ring connected by adjacent second curves and second curves, and the process also includes: using the first straight tube side wall surface to divide the first curved tube side wall surface, the second curved tube side wall surface, the third curved tube side wall surface and the fourth curved tube side wall surface between the n section and the n-1 section, and deleting the divided area; obtaining a first intersection point and a second intersection point of the first straight tube side wall surface and the curved tube side wall surface in the axial direction of the straight tube section of the volute flow channel; at the first intersection point and the second intersection point, establishing a first working plane and a second working plane respectively along the axial direction perpendicular to the straight tube section of the volute flow channel, and using the first working plane and the second working plane to cut the first straight tube side wall surface, and dividing the first straight tube side wall surface into three sub-side wall surfaces.

[0017] In this implementation, the overlapping areas of the straight pipe section and the curved pipe section are taken into consideration and the area is deleted, which can ensure the modeling accuracy of the volute flow channel. The side wall of the straight pipe is further divided according to the cut part, which can improve the smoothness of the mesh division.

[0018] In an optional embodiment, the seat ring surface is constructed based on the seat ring arc edge connected by the adjacent second curve and the second curve, including: for sections 1 to n, the seat ring surface is constructed based on the seat ring arc edge connected by the adjacent second curve and the second curve.

[0019] In a second aspect, the present invention provides a computer device, comprising: a memory and a processor, the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the finite element modeling method of the volute flow passage of the above-mentioned first aspect or any corresponding embodiment thereof by executing the computer instructions.

[0020] In a third aspect, the present invention provides a computer-readable storage medium having computer instructions stored thereon, the computer instructions being used to enable a computer to execute the finite element modeling method for a volute flow passage according to the first aspect or any corresponding embodiment thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 is a flow chart of a finite element modeling method for a volute flow passage according to an embodiment of the present invention;

[0023] Figure 2 is a volute flow channel modeling diagram according to an embodiment of the present invention;

[0024] Figure 3 is a schematic diagram of a typical cross-section local coordinate system according to an embodiment of the present invention;

[0025] Figure 4 is a schematic diagram of a straight pipe cross section according to an embodiment of the present invention;

[0026] Figure 5 is a two-dimensional schematic diagram of mesh division of a volute flow channel according to an embodiment of the present invention;

[0027] Figure 6 is another two-dimensional schematic diagram of volute flow channel mesh division according to an embodiment of the present invention;

[0028] Figure 7 is a schematic diagram of a circumferential cross section of a curved pipe according to an embodiment of the present invention;

[0029] Figure 8 is a schematic diagram of a cross-section of a curved pipe segment according to an embodiment of the present invention;

[0030] Fig. 9 is a schematic diagram of a seat ring of a volute flow passage according to an embodiment of the present invention;

[0031] Fig.10 is a schematic diagram of mesh modeling of a volute flow passage according to an embodiment of the present invention;

[0032] Fig.11 It is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0034] According to an embodiment of the present invention, an embodiment of a finite element modeling method for a volute flow passage is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0035] In this embodiment, a finite element modeling method for a volute flow passage is provided. Figure 1 is a flow chart of a finite element modeling method for a volute flow channel according to an embodiment of the present invention. It should be noted that if there are substantially the same results, this embodiment is not based on Figure 1 The process sequence shown is limited. Figure 1 As shown, the process includes the following steps:

[0036] Step S101, constructing a plurality of typical cross sections based on the cross section parameters of the volute flow passage.

[0037] According to the drawing size of the volute flow channel, multiple typical sections are selected along the volute, and the volute flow channel section is modeled according to the section parameters of the typical sections. Among them, the typical section of the straight pipe section is the straight pipe section, and the typical section of the curved pipe section is the curved pipe section.

[0038] In one implementation, the cross-sectional parameters of the volute flow passage include the distance R between the center of the cross-sectional circle and the center of the coordinate origin. i , the radius of the cross section r i , section angle α i .

[0039] Specifically, the section parameters of each typical section are obtained, and multiple typical sections are determined in the volute flow channel based on the section parameters. The typical sections are named from straight pipe sections to curved pipe sections, 0 to n sections in sequence, section 0 is a straight pipe section, and sections 1 to n are curved pipe sections.

[0040] See also Figure 2 , Figure 2 is a modeling diagram of a volute flow channel according to an embodiment of the present invention. Figure 2As shown, 21 typical sections are determined in the volute flow channel, and the typical sections are named from the straight pipe section to the curved pipe section, which are sections 0 to 20, respectively. Among them, the pipe section from section 0 to section 1 is a straight pipe section, section 0 is a straight pipe section, the pipe section from section 1 to section 20 is a curved pipe section, and sections 1 to 20 are straight pipe sections.

[0041] Furthermore, a local coordinate system is established in each typical section. Figure 3 Schematic diagram of a typical cross-section local coordinate system according to an embodiment of the present invention. Figure 3 For each typical section, a local coordinate system is constructed with the line connecting the center of the section and the origin of the coordinate system as the X-axis and the elevation direction of the volute flow passage as the Y-axis.

[0042] Step S102, for the straight tube section, construct the circumference of the straight tube section with the center of the section, evenly determine a first number of straight tube section intersections on the circumference of the straight tube section, connect the arc edges of adjacent straight tube section intersections, and construct a first number of straight tube section arc edges.

[0043] See also Figure 2 Based on the local coordinate system of the straight tube section, the circumference of the straight tube section is constructed on the straight tube section using the center of the section and the radius of the section, and the first number of straight tube section intersections with the same distance are determined on the circumference of the straight tube section, and the arc edges between adjacent straight tube section intersections are used as the arc edges of the straight tube section.

[0044] In one implementation, the first number is four. Figure 4 , Figure 4 is a schematic diagram of a straight tube section circumference according to an embodiment of the present invention, on the straight tube section circumference of the straight tube section, the first straight tube section intersection points are uniformly determined in sequence in the counterclockwise direction of the X-axis of the local coordinate system The second straight pipe section intersection The third straight pipe section intersection Intersection point with the fourth straight pipe section

[0045] Connect the first straight pipe section intersection Intersection point with the fourth straight pipe section The arc edge of the first straight tube section is constructed i 1. Connect the first straight pipe section intersection Intersection point with the second straight pipe section The arc edge of the second straight pipe section is constructed i 2. Connect the second straight pipe section intersection Intersection point with the third straight pipe section The arc edge of the third straight tube section is constructed i3. Connect the intersection of the third straight pipe section Intersection point with the fourth straight pipe section The arc edge of the fourth straight tube section is constructed to obtain the arc edge l i 4.

[0046] In one example, for section 0, take is 0°, take is 90°, take is 180°, take The circle creation method in this example is used to generate the outer mesh of the volute pipe. Figure 5 , Figure 5 It is a two-dimensional schematic diagram of volute flow channel mesh division according to an embodiment of the present invention.

[0047] In another example, for section 0, take is 45°, take is 135°, take is 225°, take The circle creation method in this example is used to generate the outer mesh of the volute pipe. Figure 6 , Figure 6 It is another two-dimensional schematic diagram of volute flow passage mesh division according to an embodiment of the present invention.

[0048] When you need to generate a concrete mesh at the top of the volute, you usually choose to stretch the volute upwards. Figure 5 and Figure 6 , Figure 5 Because the arc curvature is too large near the intersection of the first straight tube section, it is impossible to generate a high-quality mesh. Therefore, preferably, for section 0, take is 45°, take is 135°, take is 225°, take It is 315°.

[0049] Step S103, for the curved pipe section, construct the circumference of the curved pipe section with the center of the section, determine two seat ring intersections on the inner side of the curved pipe of the curved pipe section circumference based on a preset height, connect the short sides of the arc of the two seat ring intersections, and construct the arc edge of the seat ring guide vane.

[0050] See also Figure 2 Based on the local coordinate system of the elbow section, the section center and section radius are used to construct the elbow section circumference on the elbow section. Since there is a seat ring with a fixed height on the inner side of the volute flow channel, the water flows from the volute flow channel through the seat ring and the guide vane and merges into the tailwater pipe. When the finite element modeling is performed in this application, the seat ring and the guide vane are simulated on the inner side of the elbow of the elbow section circumference.

[0051] Specifically, two seat ring intersections are determined on the inner side of the bent pipe that determines the circumference of the bent pipe section according to the preset height of the seat ring, and the short sides of the arcs of the two seat ring intersections are connected to construct the arc edges of the seat ring guide vanes.

[0052] For example, see Figure 7 , Figure 7 It is a schematic diagram of the circumference of a bent pipe section according to an embodiment of the present invention, wherein a first seat ring intersection is determined at a Y-axis height H / 2 on the inner side of the bent pipe of the bent pipe section circumference, and a second seat ring intersection is determined at a Y-axis height -H / 2 on the inner side of the bent pipe of the bent pipe section circumference, and the short sides of the arc of the first seat ring intersection and the second seat ring intersection are connected to construct an arc edge of the seat ring.

[0053] like Figure 7 As shown, sections 4 and 14 are taken as examples for explanation. For the same seat ring height H, the arc lengths of the seat ring arc side corresponding to section 4 and the seat ring arc side corresponding to section 14 are different.

[0054] Step S104, based on the arc transition factor, determine the first number of bend section intersections on the long side of the arc connecting the two seat ring intersections, connect adjacent bend section intersections, connect adjacent bend section intersections and seat ring intersections, and construct the first number of bend section arc edges.

[0055] See also Figure 2 In the curved pipe section, as the angle of the curved pipe section gradually increases, the circumferential radius of the curved pipe section gradually decreases. Since the seat ring height H is a fixed value, if the first number of curved pipe section intersections is determined for the curved pipe section using the same method as the straight pipe section, the arc edge between the seat ring intersection and the curved pipe section intersection may be too small, which seriously affects the mesh quality. Therefore, the present application proposes a method for adjusting the intersection of curved pipe sections to adaptively improve the mesh quality.

[0056] Specifically, the position of the intersection point of the curved pipe section of the current curved pipe section is adjusted according to the arc transition factor and the previous curved pipe section, and a new intersection point of the curved pipe section is determined.

[0057] In one implementation, the first number is 4. When the curved pipe section is a 1 section, the curved pipe section intersection is determined using the same method as the 0 section.

[0058] Specifically, based on the local coordinate system of the curved pipe section, the circumference of the curved pipe section is constructed using the center of the section and the radius of the section, and the first curved pipe section intersection point, the second curved pipe section intersection point, the third curved pipe section intersection point and the fourth curved pipe section intersection point are determined uniformly and sequentially on the long side of the arc in the counterclockwise direction of the X-axis.

[0059] The angles of the first curved pipe section intersection, the second curved pipe section intersection, the third curved pipe section intersection and the fourth curved pipe section intersection are respectively the same as the angles of the first straight pipe section intersection, the second straight pipe section intersection, the third straight pipe section intersection and the fourth straight pipe section intersection. is 45°, take is 135°, take is 225°, take It is 315°.

[0060] Furthermore, the arc edge between the intersection point of the first elbow section and the intersection point of the first seat ring is used as the first elbow connection arc edge l 1 1′, the arc edge between the intersection of the fourth elbow section and the second seat ring is used as the second elbow connection arc edge l 1 2′.

[0061] In one implementation, the first number is four. When the cross section of the curved pipe is 2 to n cross sections, based on the arc transition factor f i The first bend of section i is connected to the arc edge l i The first arc length of 1′ determines the first bend connecting the arc edge l of the i+1 section i+ 1 1′. Based on the arc transition factor f i The second bend of section i is connected to the arc edge l i The third arc length of 2′ determines the arc edge l of the second elbow of section i+1 i+1 The length of the fourth arc is 2′.

[0062] Specifically, to ensure that the intersection of the first bend section is outside the range of the seat ring height H, and the first bend is connected to the arc edge l i 1′ and the second elbow connect to the arc edge l i 2′ transition is smooth, the arc transition factor f i As a control parameter. Among them, the first bend pipe connects the arc edge l i 1′ and the second elbow connect to the arc edge l i The determination method of 2′ is the same. The following is the first bend connecting the arc edge l i The method of determining 1′ is described as an example. Where i is the smallest section.

[0063] Please refer to Figure 7 , where the first elbow of section 1 connects to the arc edge l 1 The arc length of 1′ is:

[0064]

[0065] in,

[0066] The first elbow of section 2 connects to the arc edge l 2 The arc length of 1′ is:

[0067] arc(l 2 1′)=f i ×arc(l 1 1′).

[0068] Among them, the arc transition factor ranges from 0.6 to 0.8.

[0069] Similarly, the first bend of section i+1 connects to the arc edge l i The length of the second arc of 1′ is:

[0070] arc(l i+1 1′)=f i ×arc(l i 1′).

[0071] Further, the intersection point of the first curved pipe section is determined based on the second arc length in the positive direction of the Y axis.

[0072] Specifically, the θ of the i+1 section i+1 for:

[0073]

[0074] β of section i+1 i+1 for:

[0075]

[0076] i+1 section for:

[0077]

[0078] At section i of the curved pipe section, the angle of the intersection of the first curved pipe section is

[0079] Similarly, the angle of the intersection of the fourth elbow section is determined based on the fourth arc length in the negative direction of the Y axis.

[0080] Based on the second straight pipe section intersection point and the third straight pipe section focus, the second curved pipe section intersection point and the third curved pipe section intersection point are determined; wherein the angles of the second curved pipe section intersection point and the third curved pipe section intersection point are respectively the same as the angles of the second straight pipe section intersection point and the third straight pipe section intersection point. For example, take is 135°, take is 225°.

[0081] Further, connect the first elbow section intersection Intersection point with the fourth bend section The arc edge of the first elbow section is constructed i 1. Connect the intersection of the first elbow section Intersection point with the second elbow section The arc edge of the second elbow section is constructed i 2. Connect the intersection of the second elbow section Intersection point with the third bend section The arc edge of the third elbow section is constructed i 3. Connect the intersection of the third elbow section Intersection point with the fourth bend section The arc edge of the fourth elbow section is constructed i 4.

[0082] Step S105, for adjacent typical sections, connect the corresponding section intersections to construct a first number of first curves; for adjacent elbow sections, connect the corresponding seat ring intersections to construct two second curves.

[0083] Specifically, from the straight pipe section to the end of the curved pipe section, the first straight pipe section intersection of the adjacent straight pipe sections and the first curved pipe section intersection of the curved pipe sections are connected respectively, and the first curved pipe section intersection of the adjacent curved pipe sections are connected to generate the first curve spline1. Similarly, the second straight pipe section intersection of the adjacent straight pipe sections and the second curved pipe section intersection of the curved pipe sections are connected respectively, and the second curved pipe section intersection of the adjacent curved pipe sections are connected to generate the first curve spline2; the third straight pipe section intersection of the adjacent straight pipe sections and the third curved pipe section intersection of the curved pipe sections are connected respectively, and the third curved pipe section intersection of the adjacent curved pipe sections are connected to generate the third curve spline3; the fourth straight pipe section intersection of the adjacent straight pipe sections and the fourth curved pipe section intersection of the curved pipe sections are connected respectively, and the fourth curved pipe section intersection of the adjacent curved pipe sections are connected to generate the first curve spline4.

[0084] Specifically, for the curved pipe section, the first seat ring intersection points of adjacent curved pipe sections are connected respectively to generate the second curve spline5. Similarly, the second seat ring intersection points of adjacent curved pipe sections are connected respectively to generate the second curve spline6.

[0085] Step S106: constructing a side wall surface based on adjacent first curves and arc edges of cross sections connecting the first curves.

[0086] Specifically, use line segment l i 1. Spline i 1. l i+1 1. Spline i 4. Create side wall A i 1; Use line segment l respectively i2. Spline i 2. l i+1 2. Spline i 1 Establish side wall surface A i 2; Use line segment l respectively i 3. Spline i 3. l i+1 3. Spline i 2 Establish side wall surface A i 3; Use line segment l respectively i 4. Spline i 4. l i+1 4. Spline i 3 Establish side wall surface A i 4.

[0087] In one implementation, for section 0 and section 1, based on the adjacent first curve spline 0 1 and spline i 4. The arc edge of the first straight tube section l 0 1 and the arc edge l of the first bend section 1 1Construct the first straight tube side wall A 0 1; Based on the adjacent first curve spline 0 1 and spline 0 2. The arc edge of the second straight pipe section l 0 2 and the arc edge of the second elbow section l 1 2. Construct the second straight tube side wall surface A 0 2; Based on the adjacent first curve spline 0 2 and spline 0 3. Arc edge of the third straight pipe section l 0 3 and the arc edge l of the third bend section 1 3. Construct the third straight tube side wall surface A 0 3; Based on the adjacent first curve spline 0 3 and spline 0 4. The arc edge of the fourth straight pipe section l 0 4 and the fourth bend section arc edge l 1 4. Construct the fourth straight tube side wall surface A 0 4.

[0088] In one implementation, for sections 1 to n, based on the adjacent first curve spline i 1 and spline i 4. The arc edge of the first bend section l i 1 and l i+1 1. Construct the first elbow side wall surface A i 1; Based on the adjacent first curve splinei 1 and spline i 2. Arc edge of the second elbow section l i 2 and l i+1 2. Construct the second elbow side wall A i 2; Based on the adjacent first curve spline i 2 and spline i 3. Arc edge of the third bend section l i 3 and l i+1 3. Construct the side wall surface A of the third elbow i 3; Based on the adjacent first curve spline i 3 and spline i 4. The arc edge of the fourth bend section l i 4 and l i+1 4. Construct the side wall surface A of the fourth elbow i 4.

[0089] Furthermore, in one implementation, the present application divides the constructed sidewall surface into rewrite areas.

[0090] Specifically, Figure 8 As shown, Figure 8 Schematic diagram of a cross-section of a curved pipe according to an embodiment of the present invention. Figure 8 As shown, the end side wall surface of the curved pipe section overlaps with the side wall surface of the first straight pipe section of the straight pipe section, and the overlapping part is deleted during modeling.

[0091] like Figure 8 As shown in the figure, the volute flow passage of 20 typical sections is used for illustration. 0 1 Cut the first elbow side wall surface A between section 20 and section 19 19 1. Second elbow side wall surface A 19 2. Third elbow side wall A 19 3 and the fourth elbow side wall A 19 4, where the shaded area is the segmentation area, delete the segmentation area. 0 1 When cutting, the side wall A of the first straight tube 0 1 and the four curved pipe side walls form the first intersection point Z in the axial direction of the straight pipe section of the volute flow passage 1 and the second intersection point Z 2 .

[0092] At the first intersection point Z 1 A first working plane is established along the axial direction of the straight pipe section of the volute flow channel, and the first working plane is used to cut the side wall surface A of the first straight pipe. 0 1. As Figure 8 As shown, the cut is perpendicular to the axial direction of the straight pipe section of the volute flow channel.2 A second working plane is established along the axial direction of the straight pipe section of the volute flow channel, and the second working plane is used to cut the side wall surface A of the first straight pipe. 0 1. The two cutting operations divide the side wall surface of the first straight tube into three sub-side wall surfaces.

[0093] Step S107, constructing a seat ring surface based on the adjacent second curve and the seat ring arc edge connected by the second curve.

[0094] Specifically, for sections 1 to n, the seat ring surface is constructed based on adjacent second curves and the seat ring arc edge connected by the second curves.

[0095] See also Fig. 9 , Fig. 9 Schematic diagram of a seat ring of a volute flow channel according to an embodiment of the present invention. A seat ring with a fixed height H is arranged inside the volute, such as Fig. 9 The grey areas simulate seat rings and guide vanes.

[0096] Step S108, constructing a volute flow channel mesh based on the cross-sectional arc edge, the first curve, the second curve, the side wall surface and the seat ring surface.

[0097] See also Fig.10 , Fig.10 This is a schematic diagram of mesh modeling of a volute flow channel according to an embodiment of the present invention. Based on the cross-sectional arc edge, the first curve, the second curve, the side wall surface and the seat ring surface, different equal segment numbers are set for each edge as needed, and each surface area is divided by a mapping method or a non-mapping method to form a high-quality mesh unit of the volute flow channel.

[0098] The finite element modeling method of the volute flow channel provided in this embodiment divides the straight pipe section and the curved pipe section by constructing a typical section, and performs different mesh divisions on the straight pipe section and the curved pipe section respectively. For the straight pipe section, only a uniform side wall surface is constructed. For the curved pipe section, the influence of the seat ring guide vane on the side wall surface is considered, and the arc transition factor is used to construct a side wall surface different from the straight pipe section, which can ensure a smooth transition of the side wall surface and improve the mesh quality. Further considering that the seat ring guide vane further constructs the seat ring surface on the basis of constructing the side wall surface can improve the mesh division efficiency, thereby improving the accuracy and reliability of the simulation calculation.

[0099] Furthermore, constructing each typical section according to the cross-sectional parameters of the volute flow channel, and then constructing the corresponding local coordinate system for each typical section can facilitate different analyses of different sections and improve the efficiency of subsequent meshing. For straight pipe sections, on the basis of uniformly constructing the intersection points of the straight pipe sections, uniformly constructing the arc edges of the straight pipe sections can ensure that the curvature of each arc is the same, and the arc curvature is not too large, so that a high-quality mesh can be generated. Considering the position of the seat ring guide vane in the curved pipe section, the seat ring is determined on the inner side of the curved pipe of the Wanduan section circumference, the seat ring intersection is determined at a height of ±H / 2, and the seat ring arc edge is further determined. The seat ring guide vane can be determined in the middle of the inner side of the curved pipe. The arc transition factor is used to adjust the arc of the curved pipe section to ensure a smooth transition of the curved pipe arc and further improve the mesh quality.

[0100] See also Fig.11 , Fig.11 is a schematic diagram of the structure of a computer device provided by an optional embodiment of the present invention, such as Fig.11 As shown, the computer device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including high-speed interfaces and low-speed interfaces. Various components are connected to each other using different buses for communication, and can be installed on a common mainboard or installed in other ways as needed. The processor can process the instructions executed in the computer device, including instructions stored in or on the memory to display the graphical information of the GUI on an external input / output device (such as, a display device coupled to the interface). In some optional embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories and multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a group of blade servers, or a multi-processor system). Fig.11 A processor 10 is taken as an example.

[0101] The processor 10 may be a central processing unit, a network processor or a combination thereof. The processor 10 may further include a hardware chip. The hardware chip may be a dedicated integrated circuit, a programmable logic device or a combination thereof. The programmable logic device may be a complex programmable logic device, a field programmable gate array, a general purpose array logic or any combination thereof.

[0102] The memory 20 stores instructions executable by at least one processor 10, so that the at least one processor 10 executes the method shown in the above embodiment.

[0103] The memory 20 may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created according to the use of the computer device, etc. In addition, the memory 20 may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some optional embodiments, the memory 20 may optionally include a memory remotely arranged relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0104] The memory 20 may include a volatile memory, such as a random access memory; the memory may also include a non-volatile memory, such as a flash memory, a hard disk or a solid state drive; the memory 20 may also include a combination of the above types of memory.

[0105] The computer device also includes an input device 30 and an output device 40. The processor 10, the memory 20, the input device 30 and the output device 40 may be connected via a bus or other means. Fig.11 The example of connecting through bus is taken in the following.

[0106] The input device 30 can receive input digital or character information, and generate key signal input related to the user settings and function control of the computer device, such as a touch screen, a keypad, a mouse, a track pad, a touch pad, an indicator bar, one or more mouse buttons, a trackball, a joystick, etc. The output device 40 may include a display device, an auxiliary lighting device (e.g., an LED) and a tactile feedback device (e.g., a vibration motor), etc. The above-mentioned display device includes but is not limited to a liquid crystal display, a light emitting diode, a display and a plasma display. In some optional embodiments, the display device can be a touch screen.

[0107] The embodiment of the present invention also provides a computer-readable storage medium. The method according to the embodiment of the present invention can be implemented in hardware, firmware, or can be implemented as a computer code that can be recorded in a storage medium, or can be implemented as a computer code that is originally stored in a remote storage medium or a non-temporary machine-readable storage medium and will be stored in a local storage medium through a network download, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only storage memory, a random access memory, a flash memory, a hard disk or a solid-state hard disk, etc.; further, the storage medium can also include a combination of the above types of memories. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by a computer, a processor, or hardware, the method shown in the above embodiment is implemented.

[0108] A part of the present invention may be applied as a computer program product, such as a computer program instruction, which, when executed by a computer, can call or provide the method and / or technical solution according to the present invention through the operation of the computer. Those skilled in the art should understand that the existence of the computer program instruction in a computer-readable medium includes, but is not limited to, a source file, an executable file, an installation package file, etc., and accordingly, the way in which the computer program instruction is executed by the computer includes, but is not limited to: the computer directly executes the instruction, or the computer compiles the instruction and then executes the corresponding compiled program, or the computer reads and executes the instruction, or the computer reads and installs the instruction and then executes the corresponding installed program. Here, the computer-readable medium may be any available computer-readable storage medium or communication medium accessible to the computer.

[0109] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A finite element modeling method for a volute flow passage, characterized in that: The method comprises: Constructing multiple typical sections based on the section parameters of the volute flow channel, wherein the typical sections include a straight pipe section and a curved pipe section; For a straight tube section, a straight tube section circumference is constructed with the section center, a first number of straight tube section intersections are evenly determined on the straight tube section circumference, and arc edges of adjacent straight tube section intersections are connected to construct a first number of straight tube section arc edges; For a curved pipe section, a curved pipe section circumference is constructed with the section center, two seat ring intersections are determined on the inner side of the curved pipe of the curved pipe section circumference based on a preset height, and the arc short sides of the two seat ring intersections are connected to construct the seat ring guide vane arc edge; based on the arc transition factor, a first number of curved pipe section intersections are determined on the arc long sides connected by the two seat ring intersections, and adjacent curved pipe section intersections are connected, and adjacent curved pipe section intersections and seat ring intersections are connected to construct the first number of curved pipe section arc edges; For adjacent typical sections, corresponding section intersections are connected to construct a first number of first curves; for adjacent curved pipe sections, corresponding seat ring intersections are connected to construct two second curves; the section intersections include the straight pipe section intersections and the curved pipe section intersections; The side wall surface is constructed based on the adjacent first curve and the cross-sectional arc edge connecting the first curve; the cross-sectional arc edge includes the straight pipe cross-sectional arc edge and the curved pipe cross-sectional arc edge; Constructing a seat ring surface based on the adjacent second curve and the seat ring arc edge connected by the second curve; A volute flow channel mesh is constructed based on the cross-sectional arc edge, the first curve, the second curve, the side wall surface and the seat ring surface.

2. The finite element modeling method for volute flow passage according to claim 1, characterized in that: The construction of multiple typical sections based on the section parameters of the volute flow passage includes: Obtaining the cross-sectional parameters of the volute flow channel, wherein the cross-sectional parameters include the distance between the cross-sectional center and the center of the coordinate origin, the cross-sectional radius, and the cross-sectional angle; Determining a plurality of typical cross sections in the volute flow passage based on the cross section parameters; The typical sections are named from the straight pipe section to the curved pipe section, and are sequentially named sections 0 to n, wherein section 0 is the straight pipe section, and sections 1 to n are the curved pipe sections; For each typical section, a local coordinate system is constructed with the direction of the line connecting the center of the section and the coordinate origin as the X-axis and the elevation direction of the volute flow passage as the Y-axis.

3. The finite element modeling method for volute flow passage according to claim 2, characterized in that: For the straight tube section, the circumference of the straight tube section is constructed with the center of the section, a first number of straight tube section intersections are evenly determined on the circumference of the straight tube section, and the arc edges of adjacent straight tube section intersections are connected to construct a first number of straight tube section arc edges, including: For the straight pipe section, the circumference of the straight pipe section is constructed with the center of the section, and the first straight pipe section intersection point, the second straight pipe section intersection point, the third straight pipe section intersection point and the fourth straight pipe section intersection point are uniformly determined in sequence in the counterclockwise direction of the X-axis; The arc edge of the first straight tube section intersection and the fourth straight tube section intersection is constructed to obtain the first straight tube section arc edge, the arc edge of the first straight tube section intersection and the second straight tube section intersection is constructed to obtain the second straight tube section arc edge, the arc edge of the second straight tube section intersection and the third straight tube section intersection is constructed to obtain the third straight tube section arc edge, and the arc edge of the third straight tube section intersection and the fourth straight tube section intersection is constructed to obtain the fourth straight tube section arc edge.

4. The finite element modeling method for volute flow passage according to claim 3 is characterized in that: For the curved pipe section, the circumference of the curved pipe section is constructed with the center of the section, two seat ring intersections are determined on the inner side of the curved pipe on the circumference of the curved pipe section based on a preset height, and the short sides of the arcs of the two seat ring intersections are connected to construct the seat ring arc edge, including: For the curved pipe section, the circumference of the curved pipe section is constructed with the center of the section, a first seat ring intersection is determined at a Y-axis height H / 2 on the inner side of the curved pipe of the circumference of the curved pipe section, and a second seat ring intersection is determined at a Y-axis height -H / 2 on the inner side of the curved pipe of the circumference of the curved pipe section; The seat ring arc edge is constructed by connecting the short side of the arc of the first seat ring intersection point and the second seat ring intersection point.

5. The finite element modeling method for volute flow passage according to claim 4, characterized in that: The method of determining a first number of curved pipe section intersection points on the long side of the arc connecting the two seat ring intersection points based on the arc transition factor, connecting adjacent curved pipe section intersection points, connecting adjacent curved pipe section intersection points and seat ring intersection points, and constructing a first number of curved pipe section arc edges includes: When the elbow section is 1 section, the circumference of the elbow section is constructed with the center of the section, and the first elbow section intersection point, the second elbow section intersection point, the third elbow section intersection point and the fourth elbow section intersection point are uniformly determined on the long side of the arc in the counterclockwise direction of the X-axis; wherein the angles of the first elbow section intersection point, the second elbow section intersection point, the third elbow section intersection point and the fourth elbow section intersection point are respectively the same as the angles of the first straight section intersection point, the second straight section intersection point, the third straight section intersection point and the fourth straight section intersection point; The arc edge between the intersection point of the first elbow section and the intersection point of the first seat ring is used as the first elbow connection arc edge, and the arc edge between the intersection point of the fourth elbow section and the intersection point of the second seat ring is used as the second elbow connection arc edge; When the cross section of the curved pipe is 2 to n, based on the arc transition factor f i The first bend of section i is connected to the arc edge l i The first arc length of 1′ determines the first bend connecting the arc edge l of the i+1 section i+1 The length of the second arc of 1′ is: arc(l i+1 1′)=f i ×arc(l i 1′); wherein the arc transition factor f i Less than zero; Based on the arc transition factor f i The second bend of section i is connected to the arc edge l i The third arc length of 2′ determines the arc edge l of the second elbow of section i+1 i+1 The length of the fourth arc is 2′; The first elbow section intersection is determined based on the second arc length in the positive direction of the Y axis, the fourth elbow section intersection is determined based on the fourth arc length in the negative direction of the Y axis, and the second elbow section intersection and the third elbow section intersection are determined based on the second straight section intersection and the third straight section focus; wherein the angles of the second elbow section intersection and the third elbow section intersection are respectively the same as the angles of the second straight section intersection and the third straight section intersection; The arc edge connecting the first bend section intersection and the fourth bend section intersection is constructed to obtain the first bend section arc edge, the arc edge connecting the first bend section intersection and the second bend section intersection is constructed to obtain the second bend section arc edge, the arc edge connecting the second bend section intersection and the third bend section intersection is constructed to obtain the third bend section arc edge, and the arc edge connecting the third bend section intersection and the fourth bend section intersection is constructed to obtain the fourth bend section arc edge.

6. The finite element modeling method for volute flow passage according to claim 5, characterized in that: The step of constructing the side wall surface based on the arc edge of the cross section connecting the adjacent first curve and the first curve comprises: For section 0 and section 1, a first straight tube side wall surface is constructed based on the adjacent first curve, the first straight tube section arc edge and the first curved tube section arc edge; a second straight tube side wall surface is constructed based on the adjacent first curve, the second straight tube section arc edge and the second curved tube section arc edge; a third straight tube side wall surface is constructed based on the adjacent first curve, the third straight tube section arc edge and the third curved tube section arc edge; a fourth straight tube side wall surface is constructed based on the adjacent first curve, the fourth straight tube section arc edge and the fourth curved tube section arc edge; For sections 1 to n, based on the adjacent first curve, the arc edge of the first bend section constructs the first bend side wall surface; based on the adjacent first curve, the arc edge of the second bend section constructs the second bend side wall surface; based on the adjacent first curve, the arc edge of the third bend section constructs the third bend side wall surface; based on the adjacent first curve, the arc edge of the fourth bend section constructs the fourth bend side wall surface.

7. The finite element modeling method for volute flow passage according to claim 6, characterized in that: The step of constructing a seat ring surface based on the adjacent second curve and the seat ring arc edge connected by the second curve further includes: Using the first straight pipe side wall surface to divide the first curved pipe side wall surface, the second curved pipe side wall surface, the third curved pipe side wall surface and the fourth curved pipe side wall surface between the n section and the n-1 section, and deleting the divided areas; Obtaining a first intersection point and a second intersection point of the first straight pipe side wall surface and the curved pipe side wall surface in the axial direction of the straight pipe section of the volute flow channel; At the first intersection and the second intersection, a first working plane and a second working plane are respectively established along the axial vertical direction of the straight pipe section of the volute flow channel, and the first working plane and the second working plane are used to cut the first straight pipe side wall surface, so as to divide the first straight pipe side wall surface into three sub-side wall surfaces.

8. The finite element modeling method for volute flow passage according to claim 1, characterized in that: The step of constructing a seat ring surface based on the adjacent second curve and the seat ring arc edge connected by the second curve comprises: For sections 1 to n, the seat ring surface is constructed based on adjacent second curves and the seat ring arc edge connected by the second curves.

9. A computer device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the finite element modeling method of the volute flow passage according to any one of claims 1 to 8 by executing the computer instructions.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the finite element modeling method for the volute flow passage according to any one of claims 1 to 8.

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