Gas compressor blade slotting design method based on suction surface and pressure surface parameters

Abstract

The invention relates to a gas compressor blade slotting design method based on suction and pressure surface parameters, and belongs to the field of turbomachinery flow control. The modeling method comprises the following steps: extracting geometry of a suction surface and a pressure surface of a blade, and rotationally projecting the geometry to a plane (R, 0, Z) under a cylindrical coordinate system; in the normalization interval [0, 1], values are taken for the channel parameters of the suction surface and the pressure surface according to actual problems; generating a straight line corresponding to each channel parameter in a standard plane area, and mapping the straight line to a projection area of a blade suction surface and a blade pressure surface on a plane (R, 0, Z); the mapped straight line is rotationally projected to a blade suction surface geometry and a blade pressure surface geometry, an area defined by the mapped straight line is a channel area, and other areas are blade entities; and connecting inlet and outlet contours of the channel to finish modeling. According to the method, through the eight normalized parameters, the parameterization method of blade slotting is popularized to the real compressor blade for the first time, channel modeling with the radial jet velocity component can be achieved, and the method has high engineering applicability.

Description

Technical Field

[0001] The invention belongs to the technical field of internal flow control of turbomachinery, and in particular relates to a compressor blade slotting design method based on suction and pressure surface parameters. Background Art

[0002] Modern high-performance aircraft engines are developing towards high thrust-to-weight ratio, low fuel consumption and high reliability. In this context, the single-stage load of the compressor is gradually increasing, the adverse pressure gradient in the blade channel is gradually increasing, and the airflow is prone to boundary layer separation at the suction surface of the blade, resulting in increased flow losses and even insufficient compressor stability. Blade slotting is a passive flow control measure. Its basic principle is to use the pressure difference between the pressure surface and the suction surface of the blade to form an adaptive jet to increase the flow velocity of the airflow close to the suction surface of the blade, thereby achieving the purpose of inhibiting boundary layer separation, reducing flow losses, and improving the overall performance of the compressor. Due to the characteristics of simple structure and strong engineering applicability of blade slotting technology, researchers have conducted in-depth research on it.

[0003] Summarizing existing research, it can be found that most of the research on blade slotting technology is conducted around straight blade cascades, and its application in real compressor blades accounts for only a small number. However, there is a certain gap between the geometric shape and inlet conditions of real compressor blades and blade cascades. In particular, the geometric shape of real compressor blades generally adopts a bending and twisting design, which makes the application of blade slotting technology in real compressor environments subject to certain restrictions. At the same time, since the blade shape of real compressor blades changes with the change of blade height, this increases the difficulty of parameterization of blade slotting technology on real compressors. Therefore, in order to solve this problem and improve the engineering applicability of blade slotting technology on real compressors, the present invention proposes a compressor blade slotting design and method based on suction and pressure surface parameters. Summary of the invention

[0004] Technical issues to be solved:

[0005] In order to avoid the shortcomings of the prior art, the present invention provides a compressor blade slotting design method based on suction and pressure surface parameters, which reduces the difficulty of parameterization of blade slotting technology on real compressor blades. At the same time, this method can also be applied to the study of blade grids, and has strong engineering application value. This method is suitable for optimization research and parameterization research, and can seek the optimal slot structure or establish a parameterized model in the entire blade physical space. In addition, this method can construct a slot structure in which the upper (lower) wall surface of the slot inlet and the upper (lower) wall surface of the slot outlet are not at the same height, so that the adaptive jet has a radial velocity component. The results show that reasonable slot parameter settings can improve the overall performance under small flow conditions without reducing the efficiency of the design point.

[0006] The technical solution of the present invention is: a compressor blade slot design method based on suction and pressure surface parameters, and the specific steps are as follows:

[0007] Extract the blade suction and pressure surface geometry, and rotate and project it onto the plane (R, 0, Z) in the cylindrical coordinate system;

[0008] In the normalized interval [0, 1], the suction and pressure surface channel parameters are selected according to the actual problem;

[0009] Generate a straight line corresponding to each channel parameter in the standard plane area, and map it to the projection area of ​​the blade suction and pressure surfaces on the plane (R, 0, Z);

[0010] The mapped straight line is rotated and projected onto the blade suction and pressure surface geometry. The area enclosed by the mapped straight line is the groove area, which forms the groove inlet and outlet contours on the suction and pressure surfaces, and the remaining area is the blade entity.

[0011] Connect the inlet and outlet contours of the channel to complete the shape.

[0012] A further technical solution of the present invention is: the suction and pressure surfaces are geometrically rotated and projected onto a plane (R, 0, Z) in a cylindrical coordinate system for coordinate marking, and the coordinates (z A ,r A ), the coordinates of the projection point B of the blade tip trailing edge (z B ,r B ), the coordinates of the projection point C of the leading edge of the blade root (z C ,r C ) and the coordinates of the projection point D of the blade root trailing edge (z D ,r D );Record curve L AB , curve L CD , curve L AC and curve L BD The coordinates of the control points are fitted by a sixth-order polynomial to obtain the fitting equation of the corresponding curve R = f AB (Z), R = f CD (Z), Z = f AC (R) and Z = f BD (R).

[0013] A further technical solution of the present invention is that the suction surface groove parameters and the pressure surface groove parameters need to be taken in the normalized interval [0, 1], including 4 suction surface groove dimensionless parameters and 4 pressure surface groove dimensionless parameters, which are: radial position of the upper wall surface near the casing groove outlet Radial position of the lower wall surface near the hub groove outlet Axial position of the left wall of the slot outlet near the leading edge of the blade Axial position of the right wall surface of the slot outlet near the blade trailing edge Radial position of the upper wall surface near the casing groove inlet Radial position of the lower wall surface near the hub groove inlet Axial position of the left wall of the slot inlet near the leading edge of the blade and the axial position of the right wall of the slot inlet near the blade trailing edge

[0014] A further technical solution of the present invention is: for the values ​​of the suction surface groove parameters and the pressure surface groove parameters, Latin hypercube sampling or Monte Carlo random sampling method can be used to obtain them when conducting optimization research; in parametric research, the groove parameters and selection can be based on the design experience of existing literature.

[0015] A further technical solution of the present invention is that this design method can complete the modeling without the radial component of the jet velocity and with the radial component of the jet velocity; if it is necessary to design a channel structure without the radial component of the jet velocity, it is only necessary to make and Simplified the 8 slot parameters to 6.

[0016] A further technical solution of the present invention is that the channel parameters should satisfy the following constraints:

[0017]

[0018]

[0019]

[0020]

[0021]

[0022]

[0023]

[0024]

[0025] Among them: Formula (1)(2) indicates that the upper wall of the slot is always higher than the lower wall of the slot; Formula (3)(4) indicates that the right wall of the slot is always located downstream of the left wall of the slot, and the slot width is not greater than 30% of the axial chord length. Studies have shown that excessive slot width will lead to a large loss of efficiency at the compressor design point, so the slot width is controlled to be no greater than 30% of the axial chord length; Formula (5)(6) indicates that when the upper / lower wall of the slot inlet and the upper / lower wall of the slot outlet are not at the same radial height, in order to ensure that the orthogonality of the grid meets the calculation requirements, the difference between the two is controlled to be no greater than 15% of the blade height; in order to prevent the slot jet direction from being opposite to the mainstream direction, thereby generating a large mixing loss, Formula (7)(8) indicates that the left / right wall of the slot inlet is always located downstream of the left / right wall of the slot outlet.

[0026] A further technical solution of the present invention is: according to the parameters and Generating straight lines in a standard plane area The area enclosed by the above four straight lines is the slot outlet area, and the rest is the blade entity; according to the parameters and Generating straight lines in a standard plane area and The area enclosed by the above four straight lines is the slot inlet area, and the rest is the blade entity.

[0027] A further technical solution of the present invention is: the straight line corresponding to each channel parameter is extended to the edge of the standard plane area to obtain point a * , b * 、c * d * 、e * 、f * , g * and h * , project each point onto the plane (R,0,Z) of the cylindrical coordinate system, and on the curve L AB , curve L CD , curve L AC , curve L BD The corresponding points a, b, c, d, e, f, g and h are obtained respectively, and their coordinates are (r i ,0,z i ), where i=a,b,…,h.

[0028] A further technical solution of the present invention is: the coordinate calculation formula of the points a, b, c, d, e, f, g and h on the plane (R, 0, Z) is as follows:

[0029]

[0030]

[0031]

[0032]

[0033]

[0034]

[0035]

[0036]

[0037] A further technical solution of the present invention is: the method for obtaining the inlet and outlet contours of the channel is: connecting points a and c, b and d, e and g, f and h with straight lines to obtain a closed curve ∮ 1234 ; The closed curve obtained 1234 is the projection of the intersection of the channel structure and the suction surface / pressure surface on the plane (R, 0, Z), the closed curve ∮ 1234 Internal corresponding channel outlet / inlet range, closed curve ∮ 1234 The outside corresponds to the solid blade surface without groove processing; the geometry of the groove inlet and outlet contours is connected to complete the modeling, and the line type used for the connection is a straight line, an arc, a cycloid, a C-spline curve or a B-spline curve.

[0038] A further technical solution of the present invention is: after the suction and pressure surface channel parameters are determined, the characteristic parameter calculation formula corresponding to the channel geometry is as follows:

[0039]

[0040]

[0041]

[0042]

[0043]

[0044]

[0045] φ=A ss / A ps (twenty three)

[0046] Where H is the average blade height, Ca is the average axial chord length; Δr ps is the radial height of the groove inlet, Δz ps is the inlet slot width, Δr ss is the radial height of the slot outlet, Δz ssis the outlet slot width, θ axial is the axial jet angle, θ radial is the radial jet angle and φ is the channel contraction rate.

[0047] Beneficial Effects

[0048] The beneficial effects of the present invention are as follows: the present invention can quickly complete the groove modeling on a real compressor blade with a bending and twisting design through only 8 normalized parameters, and for the first time extends the systematic modeling method of blade slotting to real compressor blades, thereby reducing the difficulty of parameterization of blade slotting on real compressor blades, and has strong engineering applicability.

[0049] Among them, the suction and pressure surface parameters are obtained in the normalized interval [0,1], which solves the difficulty of parameterization of blade slotting technology on compressor blades with bending and twisting design; The groove inlet radial height Δr can be quickly determined based on the above 8 suction and pressure surface parameters. ps , inlet slot width Δz ps , radial height of groove outlet Δr ss , outlet slot width Δz ss 、Axial jet angle θ axial 、Radial jet angle θ radial , channel shrinkage rate φ and other channel characteristic parameters provide convenience for subsequent flow field analysis and data mining.

[0050] The present invention proposes for the first time a channel structure and design method with radial jet velocity components. and and When they are not equal, the upper wall of the groove (close to the casing) and the lower wall of the groove (close to the hub) are no longer horizontal, which makes the jet velocity have a certain radial component, in order to explore the influence of the adaptive jet with radial velocity component on the internal flow field of the compressor.

[0051] The present invention solves the engineering application problem of blade slotting technology on real compressor blades, and is still applicable to blade cascade research. The present invention has the characteristics of simple design method, convenient processing and manufacturing, and high speed. In the optimization research, the calculation grid can be quickly generated in combination with the macro instruction program, with a speed of about 35 to 45 per minute.

[0052] In the optimization studies conducted using this design method, Figure 8 and Fig. 9The compressor total pressure ratio and efficiency curve of the optimal solution are shown in Figure 2. It can be seen that the blade slot structure obtained by this modeling method improves the compressor efficiency under small flow conditions by 1.27% without significantly affecting the design point efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 The present invention is a flow chart of a compressor blade slotting design and method based on suction and pressure surface parameters.

[0054] Figure 2 It is the rotational projection of the compressor blade on the plane (R, 0, Z) in the cylindrical coordinate system.

[0055] Figure 3 It is a schematic diagram of the groove area enclosed by the straight lines formed by the groove parameters in the standard plane area.

[0056] Figure 4 It is a schematic diagram of the groove area enclosed by the straight lines formed by the groove parameters on the plane (R, 0, Z) in the cylindrical coordinate system.

[0057] Figure 5 Schematic diagram of the three-dimensional structure of compressor blades and grooves.

[0058] Figure 6 The streamline diagram on the 99% blade height section of the original compressor stator blade is a compressor blade slotting design and method based on suction and pressure surface parameters.

[0059] Figure 7 The streamline diagram on the 99% blade height section after the stationary blade is slotted is a compressor blade slotting design and method based on suction and pressure surface parameters.

[0060] Figure 8 The compressor total pressure ratio curve of the optimal solution obtained by using this design method to optimize blade slotting.

[0061] Fig. 9 The compressor efficiency curve of the optimal solution obtained by using this design method to optimize blade slotting.

[0062] Explanation of reference numerals: A: projection of the leading edge point of the blade tip on the plane (R, 0, Z); B: projection of the trailing edge point of the blade tip on the plane (R, 0, Z); C: projection of the leading edge point of the blade root on the plane (R, 0, Z); D: projection of the trailing edge point of the blade root on the plane (R, 0, Z); Radial position of the upper wall surface (near the casing) of the slot outlet; Radial position of the lower wall surface (near the hub) at the slot outlet; Axial position of the left wall of the slot outlet (near the leading edge of the blade); Axial position of the right wall of the slot outlet (near the trailing edge of the blade); closed curve ∮ 1234 : The projection of the intersection line of the channel structure and the suction surface of the blade on the plane (R, 0, Z); closed curve ∮ 1234_PS : The intersection line between the channel structure and the blade pressure surface; closed curve ∮ 1234_SS : The intersection line between the groove structure and the suction surface of the blade. DETAILED DESCRIPTION

[0063] The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, but should not be construed as limiting the present invention.

[0064] Based on the problem that it is difficult to parameterize slotting on real compressor blades in the prior art, the present invention provides a compressor blade slotting design method based on suction and pressure surface parameters. Figures 1 to 9 , the specific implementation methods of the present invention are described in detail. The research object selected in this embodiment is the NASA Stage35 stator blade, but the research object of the present invention is not limited to this research object.

[0065] Table 1 Basic design parameters of NASA Stage 35

[0066]

[0067] Reference Figure 1 As shown, the compressor blade slotting design and method based on suction and pressure surface parameters in this embodiment mainly involves the following five steps.

[0068] Step 1: Extract the blade suction and pressure surface geometry, and rotate and project it onto the plane (R, 0, Z) in the cylindrical coordinate system;

[0069] Step 2: In the normalized interval [0, 1], select the values ​​of the suction and pressure surface channel parameters according to the actual problem;

[0070] Step 3: Generate a straight line corresponding to each slot parameter in the standard plane area, and map it to the projection area of ​​the blade suction and pressure surfaces on the plane (R, 0, Z);

[0071] Step 4: Rotate and project the mapped straight line onto the blade suction and pressure surface geometry. The area enclosed by the mapped straight line is the groove area, and the remaining area is the blade entity.

[0072] Step 5: Connect the inlet and outlet contours of the channel to complete the shape.

[0073] Specifically, the work required in step 1 is as follows: According to the existing blade GeomTurbo file, the blade suction surface geometry and blade pressure surface geometry are obtained and stored separately.

[0074] Specifically, refer to Figure 2 As shown, the suction surface or pressure surface of the blade is geometrically rotated and projected onto the plane (R, 0, Z) in the cylindrical coordinate system (whether it is the pressure surface or the suction surface, its projection on the plane (R, 0, Z) basically coincides). The unit of the geometric model selected in this example is millimeter (mm), and the coordinates of the leading edge projection point A of the blade tip (44.7435116, 242.813480), the coordinates of the trailing edge projection point B of the blade tip (85.251257, 240.175959), the coordinates of the leading edge projection point C of the blade root (47.510791, 188.050054) and the coordinates of the trailing edge projection point D of the blade root (83.072689, 192.178182) are recorded for use in mapping the lines in step 5.

[0075] Recording curve L AB The control point coordinates of the curve L CD The control point coordinates of the curve L AC The control point coordinates and curve L BD The corresponding straight line equation is approximated by the sixth-order polynomial fitting method.

[0076] f AB (Z) = 4890955.5 × Z 6 -2028320.8×Z 5 +348710.7×Z 4 -31796.5×Z 3 +1620.7×Z 2 -43.8×Z+0.7

[0077] f CD (Z) = -9659533.2 × Z 6 +3806168.5×Z 5 -619300.5×Z 4 -53247.8×Z 3 -2551.7×Z 2 +64.8×Z-0.5

[0078] f AC (R) = -4303828 × R 6 +5613735.3×R 5 -3046423.3×R 4 +880377.8×R 3 -142889.7×R 2 +12349.5×R-443.9

[0079] f BD (R) = -663435.9 × R6 +855100.3×R 5 -457650×R 4 +130160.4×R 3 -20743.7×R 2 +1756.1×R-61.6

[0080] Note: When the selected geometric model unit is meter (m), on the curve L AC and curve L BD (or curve L AB and curve L CD ), the corresponding Z (or R) coordinate values ​​do not change much. If the values ​​in meters (m) are continued to be used for sixth-order polynomial fitting, the fitting accuracy may be reduced. Therefore, the scaling method is adopted to magnify the coordinate values ​​by 1000 times and then perform sixth-order polynomial fitting. Then, the independent variable and dependent variable of the sixth-order polynomial function are reduced by 1000 times to obtain the fitting equation.

[0081] Specifically, in step 2, within the normalized interval [0,1], four dimensionless parameters of the suction surface groove and four dimensionless parameters of the pressure surface groove (dimensionless parameters are indicated by superscript "*") are taken for use in the standard plane area. Including: radial position of the upper wall surface (near the casing) of the groove outlet Radial position of the lower wall of the groove outlet (near the hub) Radial position of the left wall of the slot outlet (near the leading edge of the blade) Radial position of the right wall of the slot outlet (near the blade trailing edge) Radial position of the upper wall of the groove inlet (near the casing) Radial position of the lower wall of the groove inlet (near the hub) Radial position of the left wall of the slot inlet (near the leading edge of the blade) and radial position of the right wall of the slot inlet (near the blade trailing edge)

[0082] If the upper (lower) wall surface of the slot inlet and the upper (lower) wall surface of the slot outlet are at the same radial height, that is, and , 8 channel parameters can be simplified to 6. (This example uses 8 channel parameters to model the channel structure with the radial component of the jet velocity).

[0083] The values ​​of the channel parameters must meet the following constraints.

[0084]

[0085]

[0086]

[0087]

[0088]

[0089]

[0090]

[0091]

[0092] Constraints (1) and (2) stipulate that the upper wall of the groove is always higher than the lower wall of the groove.

[0093] Constraints (3) and (4) stipulate that the right wall of the slot is always located downstream of the left wall of the slot, and the slot width is not greater than 30% of the axial chord length. Previous studies have shown that excessive slot width will lead to a large loss of compressor design point efficiency, so the slot width is controlled to be no greater than 30% of the axial chord length.

[0094] To ensure that the orthogonality of the grid meets the calculation requirements, constraints (5) and (6) stipulate that when the upper (lower) wall surface of the slot inlet and the upper (lower) wall surface of the slot outlet are not at the same radial height, the difference between the two is controlled to be no more than 15% of the blade height.

[0095] In order to prevent the channel jet direction from being opposite to the mainstream direction, thus causing large mixing losses, constraints (7) and (8) stipulate that the left (right) wall of the channel inlet is always located downstream of the left (right) wall of the channel outlet.

[0096] Specifically, the work required for step 3 is as follows: Taking the suction side as an example (the same applies to the pressure side), according to the parameters and Generating straight lines in a standard plane area and The above four straight lines divide the standard plane area into two parts - the shaded part (blade entity) and the blank part (slot empty body), and point a is obtained. * 、b * 、c * d * 、e * 、f * , g * and h * ,like Figure 3 shown.

[0097] Specifically, refer to Figure 4 As shown, point a in the standard plane area * 、b * 、c* d * 、e * 、f * , g * and h * , projected onto the plane (R, 0, Z) of the cylindrical coordinate system, we get points a, b, c, d, e, f, g, and h, with coordinates (r i ,0,z i ), where (i=a,b,…,h).

[0098] The coordinates of each point a, b, c, d, e, f, g, and h (r i ,0,z i ), (i=a,b,...,h), calculated according to the following formula:

[0099]

[0100]

[0101]

[0102]

[0103]

[0104]

[0105]

[0106]

[0107] Connect a and c, b and d, e and g, f and h with straight lines to form a closed curve ∮ 1234 is the projection of the intersection line of the channel structure and the suction surface on the plane (R, 0, Z), the closed curve ∮ 1234 The internal corresponding channel outlet range, closed curve ∮ 1234 The outer part corresponds to the solid blade surface without grooves.

[0108] Specifically, the work required for step 4 is as follows: 1234 By rotating and projecting onto the suction surface geometry of the blade, the intersection line of the channel structure and the suction surface is obtained. Similarly, the intersection line of the channel structure and the pressure surface is obtained, that is, the inlet and outlet contours of the channel.

[0109] Specifically, the work required for step five is as follows: Figure 5 As shown, the corresponding points of the groove inlet contour and the groove outlet contour are connected by straight lines to obtain the three-dimensional structure of the groove.

[0110] In this example, the connection form of the inlet and outlet contours of the channel is a straight line, but the connection form of the inlet and outlet contours involved in the present invention can also be connected by lines such as arcs, cycloids, C-spline curves, and B-spline curves.

[0111] After completing the three-dimensional modeling of the slot structure, a numerical study on how blade slotting can suppress boundary layer separation was carried out.

[0112] The Autogrid5 module of the NUMECA software installation package is used to perform structured meshing on the blade passage mesh of the NASA Stage35 compressor.

[0113] The IGG module of the NUMECA software installation package is used to perform structured meshing on the channel mesh.

[0114] The Fine-Turbo module of the NUMECA software installation package is used for numerical calculation, and the Euranus solver is used to perform full three-dimensional calculation on the generated numerical calculation grid. The specific configuration is that the compressor rotor speed is 17188.8r / min, the spatial discretization format of the control equation adopts the second-order upwind Symmetric TVD scheme, the oscillation restriction type of the numerical solution in the linear domain and the nonlinear domain selects the Min Mod format, and the multi-grid method, local time step and implicit residual smoothing are used to accelerate the convergence speed.

[0115] Use the CFView module of the NUMECA software installation package to obtain numerical calculation results and perform data processing.

[0116] The research results show that the groove structure greatly suppresses the boundary layer separation of the blade suction surface and reduces flow losses; a reasonable groove structure can increase the efficiency of the compressor by 1.8 in near-stall conditions and cause a 0.25% design efficiency loss.

[0117] The characteristic parameters of the channel structure are obtained according to the following formula:

[0118]

[0119]

[0120]

[0121]

[0122]

[0123]

[0124] φ=A ss / A ps(twenty three)

[0125] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention without departing from the principles and intent of the present invention.

Claims

1. A compressor blade slot design method based on suction and pressure surface parameters, characterized in that The specific steps are as follows: Extract the blade suction and pressure surface geometry, and rotate and project it onto the plane (R, 0, Z) in the cylindrical coordinate system; In the normalized interval [0, 1], the suction and pressure surface channel parameters are selected according to the actual problem; Generate a straight line corresponding to each channel parameter in the standard plane area, and map it to the projection area of ​​the blade suction and pressure surfaces on the plane (R, 0, Z); The mapped straight line is rotated and projected onto the blade suction and pressure surface geometry. The area enclosed by the mapped straight line is the groove area, which forms the groove inlet and outlet contours on the suction and pressure surfaces, and the remaining area is the blade entity. Connect the inlet and outlet contours of the channel to complete the shape.

2. A compressor blade slot design method based on suction and pressure surface parameters according to claim 1, characterized in that: The suction and pressure surfaces are geometrically rotated and projected onto the plane (R, 0, Z) in the cylindrical coordinate system for coordinate marking, and the coordinates (z A ,r A ), the coordinates of the projection point B of the blade tip trailing edge (z B ,r B ), the coordinates of the projection point C of the leading edge of the blade root (z C ,r C ) and the coordinates of the projection point D of the blade root trailing edge (z D ,r D );Record curve L AB , curve L CD , curve L AC and curve L BD The coordinates of the control points are fitted by a sixth-order polynomial to obtain the fitting equation of the corresponding curve R = f AB (Z), R = f CD (Z), Z = f AC (R) and Z = f BD (R).

3. A compressor blade slot design method based on suction and pressure surface parameters according to claim 2, characterized in that: The suction surface groove parameters and pressure surface groove parameters need to be taken in the normalized interval [0, 1], including 4 suction surface groove dimensionless parameters and 4 pressure surface groove dimensionless parameters, which are: radial position of the upper wall near the casing groove outlet Radial position of the lower wall surface near the hub groove outlet Axial position of the left wall of the slot outlet near the leading edge of the blade Axial position of the right wall surface of the slot outlet near the blade trailing edge Radial position of the upper wall surface near the casing groove inlet Radial position of the lower wall surface near the hub groove inlet Axial position of the left wall of the slot inlet near the leading edge of the blade and the axial position of the right wall of the slot inlet near the blade trailing edge 4. The compressor blade slot design method based on suction and pressure surface parameters according to claim 3, characterized in that: When the channel structure is a channel structure without a radial component of the jet velocity, let and Simplified the 8 slot parameters to 6.

5. The compressor blade slot design method based on suction and pressure surface parameters according to claim 3, characterized in that: The channel parameters should meet the following constraints: Among them: formula (1)(2) indicates that the upper wall of the slot is always higher than the lower wall of the slot; formula (3)(4) indicates that the right wall of the slot is always downstream of the left wall of the slot, and the slot width is not greater than 30% of the axial chord length; formula (5)(6) indicates that the difference between the upper / lower wall of the slot inlet and the upper / lower wall of the slot outlet is controlled to be no greater than 15% of the blade height; formula (7)(8) indicates that the left / right wall of the slot inlet is always downstream of the left / right wall of the slot outlet.

6. A compressor blade slot design method based on suction and pressure surface parameters according to claim 5, characterized in that: According to the parameters and Generating straight lines in a standard plane area The area enclosed by the above four straight lines is the slot outlet area, and the rest is the blade entity; according to the parameters and Generating straight lines in a standard plane area and The area enclosed by the above four straight lines is the slot inlet area, and the rest is the blade entity.

7. A compressor blade slot design method based on suction and pressure surface parameters according to claim 6, characterized in that: The straight line corresponding to each slot parameter is extended to the edge of the standard plane area to obtain point a * 、b * 、c * d * 、e * 、f * , g * and h * , project each point onto the plane (R,0,Z) of the cylindrical coordinate system, and on the curve L AB , curve L CD , curve L AC , curve L BD The corresponding points a, b, c, d, e, f, g and h are obtained respectively, and their coordinates are (r i ,0,z i ), where i=a,b,…,h.

8. A compressor blade slot design method based on suction and pressure surface parameters according to claim 7, characterized in that: The coordinate calculation formulas of the points a, b, c, d, e, f, g and h on the plane (R, 0, Z) are as follows:

9. A compressor blade slot design method based on suction and pressure surface parameters according to claim 8, characterized in that: The method for obtaining the groove inlet and outlet contours is: connect points a and c, b and d, e and g, f and h with straight lines to obtain a closed curve The obtained closed curve It is the projection of the intersection line of the channel structure and the suction surface / pressure surface on the plane (R, 0, Z), a closed curve Internal corresponding channel outlet / inlet range, closed curve The outside corresponds to the solid blade surface without groove processing; the geometry of the groove inlet and outlet contours is connected to complete the modeling, and the line type used for the connection is a straight line, an arc, a cycloid, a C-spline curve or a B-spline curve.

10. A compressor blade slot design method based on suction and pressure surface parameters according to claim 9, characterized in that: After the suction and pressure surface channel parameters are determined, the calculation formula for the characteristic parameters of the corresponding channel geometry is as follows: φ=A ss / A ps (23) Where H is the average blade height, Ca is the average axial chord length; Δr ps is the radial height of the groove inlet, Δz ps is the inlet slot width, Δr ss is the radial height of the slot outlet, Δz ss is the outlet slot width, θ axial is the axial jet angle, θ radial is the radial jet angle and φ is the channel contraction rate.

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