A design method of binary hypersonic inlet rear step bleed slot

Abstract

The application relates to a design method of a binary hypersonic air inlet rear step bleed channel, comprising the following steps: obtaining a binary air inlet configuration; wherein the binary air inlet configuration comprises a lip cover inner wall surface, a compression wall surface opposite to the lip cover inner wall surface, a lip opening formed by the lip cover inner wall surface and the compression wall surface, and a throat; obtaining a first positioning point for positioning an initial position of a bleed channel on the compression wall surface based on a lip opening point of the lip cover inner wall surface at a lip opening position; taking the first positioning point as a starting point, arranging a second positioning point on both sides of the first positioning point at a preset distance; generating a plurality of bleed channels with intervals based on the first positioning point and the second positioning point at a preset width and a preset inclination angle; and arranging a rear step structure on the rear side of the bleed channel in the direction from the lip opening to the throat. The application realizes excellent peeling capacity of a large-scale separation zone in air inlet design.

Description

Technical Field

[0001] This invention relates to the field of scramjet engines, and more particularly to a design method for a rear stepped venting groove in a two-dimensional hypersonic inlet. Background Technology

[0002] Scramjet engines are the primary power source for hypersonic vehicles, and the hypersonic air intake is a key component of a scramjet engine. Scramjet engines do not carry oxidizer; they directly capture oxygen from the air through the air intake to initiate combustion. The starting range of the air intake directly determines the engine's operating range and reliability.

[0003] Studies have shown that adding a bleed groove structure to the intake can effectively reduce the intake's self-starting Mach number. However, after the intake starts, the actual air capture flow of the engine is reduced due to the bleed groove's leakage. Existing research shows that changing the layout and slotting angle of the bleed groove can effectively reduce the flow loss during intake start-up. Chen Haoyu et al.'s research shows that by changing the layout and slotting angle of the bleed groove, the flow loss of the intake under design conditions can be significantly reduced. (Chen Haoyu, Huang Hexia, Tan Huijun. The Influence of Bleed Groove Layout and Slotting Angle on the Performance of Two-Dimensional Hypersonic Intake [J]. Gas Physics, 2023, Vol. 8 (2): 24-31, 5). In addition, most bleed grooves currently adopt a stepless structure. This structure only completes the suction of the large-scale separation zone or the stripping of the boundary layer through the pressure difference at both ends of the bleed groove, and its effect needs to be improved. Wang Yi added a front-step venting groove structure to the air intake, and the boundary layer stripping was completed by the height difference and pressure difference of the venting groove wall. He found that the stripping effect of this structure was significantly better than that of the structure without steps (Wang Yi. Research on the start-up problem of hypersonic air intake [D]. Changsha: National University of Defense Technology, 2008). However, the front-step venting groove structure will further aggravate the flow loss after the air intake starts.

[0004] Therefore, it can be seen that the current hypersonic inlet design process has the following main drawbacks:

[0005] 1. Currently, the venting groove structure in hypersonic inlets mostly adopts a stepless structure, and the effect of suction or boundary layer stripping in large-scale separation zones needs to be improved.

[0006] 2. The front step bleed groove structure will further increase the loss of engine capture flow after the intake manifold starts. Summary of the Invention

[0007] The purpose of this invention is to provide a design method for a venting groove on the rear step of a two-dimensional hypersonic inlet, which overcomes the defects of the prior art, such as the high self-starting Mach number of the inlet and the large venting flow rate of the venting groove under the design point operating conditions.

[0008] To achieve the above-mentioned objectives, this invention provides a design method for a rear stepped vent groove in a two-dimensional hypersonic inlet, comprising the following steps:

[0009] S1. Obtain a two-dimensional air intake configuration; wherein, the two-dimensional air intake configuration includes: an inner wall surface of a lip cover, a compression wall surface opposite to the inner wall surface of the lip cover, and a lip and throat formed by the inner wall surface of the lip cover and the compression wall surface;

[0010] S2. Based on the lip point at the lip opening position of the inner wall of the lip cover, obtain the first positioning point on the compression wall surface used to locate the initial position of the venting groove;

[0011] S3. Taking the first positioning point as the starting point, arrange the second positioning points at a preset distance on both sides of the first positioning point;

[0012] S4. Based on the first positioning point and the second positioning point, generate multiple venting grooves with a preset width and a preset tilt angle, respectively;

[0013] S5. A rear step structure is provided on the rear side of the venting groove along the direction from the lip to the throat.

[0014] According to one aspect of the invention, in step S2, the first positioning point is the projection point of the lip point on the compression wall surface.

[0015] According to one aspect of the present invention, in step S3, in the step of arranging second positioning points at a preset distance on both sides of the first positioning point, it is determined whether the length of the compression wall between adjacent positioning points meets the preset distance; if it does, the arranged second positioning points are retained.

[0016] If the condition is not met, the second positioning point is rearranged so that the length of the compressed wall between adjacent positioning points is equal to the preset distance.

[0017] According to one aspect of the present invention, in step S4, in the step of generating a plurality of venting grooves with intervals based on the first positioning point and the second positioning point with a preset width and a preset tilt angle respectively, the first positioning point and the second positioning point are respectively the midpoints of the corresponding venting grooves in the width direction.

[0018] According to one aspect of the present invention, in step S4, the width and tilt angle of the generated plurality of venting grooves are independent of each other.

[0019] According to one aspect of the present invention, in step S5, in the step of providing a rear step structure on the rear side of the venting groove, the rear step structure includes: a first smooth transition surface and an inclined extension surface;

[0020] One end of the inclined extension surface is connected to the compression wall surface, and the other end is sunken and extends inclinedly towards the rear wall surface of the venting groove.

[0021] The first smooth transition surface is used to connect the rear wall surface of the venting groove and the inclined extension surface.

[0022] According to one aspect of the present invention, step S5, which involves providing a rear step structure on the rear side of the venting groove along the direction from the lip to the throat, includes:

[0023] S51. Determine a first boundary point of the rear step structure on the rear wall surface of the venting groove, and determine a second boundary point of the rear step structure on the compression wall surface;

[0024] S52. Determine the shape and parameters of the first smooth transition surface, and use the tangency of the first smooth transition surface with the rear wall of the venting groove at the first boundary point as the first constraint, and the tangency of the inclined extension surface with the first smooth transition surface as the second constraint, to generate the first smooth transition surface and the inclined extension surface.

[0025] According to one aspect of the present invention, in step S51, in the step of determining the first boundary point of the rear step structure on the rear wall surface of the venting groove, the point on the rear wall surface is projected onto the compression wall surface and a first projection distance is obtained. It is determined whether the first projection distance satisfies the first preset length. If it does, the current point is taken as the first boundary point.

[0026] In step S51, the step of determining the second boundary point of the rear step structure on the compressed wall surface includes:

[0027] Determine whether the venting groove is the last one along the direction from the lip to the throat;

[0028] If not, then the intersection of the front wall surface of the next venting groove and the compression wall surface shall be taken as the second boundary point of the rear step structure of the previous venting groove.

[0029] If so, the intersection of the front wall of the venting groove and the compression wall is used as a reference point, and the second boundary point of the rear step structure of the venting groove is obtained on the compression wall using the reference point and the second preset length.

[0030] According to one aspect of the present invention, in step S3, the preset distance satisfies: L = dH0, where L represents the preset distance, H0 represents the standard length, that is, the distance between the first positioning point and the lip point, 0.50 ≤ d ≤ 2.00;

[0031] In step S4, the preset width satisfies: D = eH0, where D represents the preset width, H0 represents the standard length, and 0.01 ≤ e ≤ 0.10;

[0032] The preset tilt angle satisfies: 90° < θ < 180°;

[0033] In step S51, the first preset length satisfies: H1 = bH0, where H1 represents the first preset length, H0 represents the standard length, and 0.05 ≤ b ≤ 0.10;

[0034] The second preset length satisfies: H2 = fH0, where H2 represents the second preset length, H0 represents the standard length, and 0.50 ≤ f ≤ 2.00.

[0035] According to one aspect of the present invention, in step S52, in the step of generating the first smooth transition surface and the inclined extension surface, if the venting groove is the last one along the direction from the lip to the throat, a second smooth transition surface is provided between the connection position of the rear step structure of the venting groove and the compression wall surface.

[0036] In step S52, in the step of determining the shape and parameters of the first smooth transition surface, the first smooth transition surface is an arc surface, and its radius satisfies: R1=aH0, where 0.05≤a≤0.10;

[0037] The second smooth transition surface is an arc surface, which is tangent to the inclined extension surface and the compression wall surface respectively. The radius of the second smooth transition surface satisfies: R2=cH0, where 0.10≤c≤0.15.

[0038] According to one aspect of the present invention, the design method of the present invention achieves excellent separation capability in the large-scale separation zone of the air intake design, effectively improving the working performance of the air intake.

[0039] According to one aspect of the present invention, the design of the venting groove angle and the rear step structure reduces the difficulty of suction and boundary layer stripping in the large-scale separation zone, thereby further reducing the self-starting Mach number of the intake duct and reducing the flow loss after the intake duct starts.

[0040] According to one aspect of the present invention, the flow direction of the large-scale separation zone near the wall in the direction of the venting channel is basically the same, which reduces the difficulty of venting the large-scale separation zone and thus further reduces the self-starting Mach number of the intake duct.

[0041] According to one aspect of the present invention, the rear step venting groove blocks the backflow of the large-scale separation zone through the height difference of the rear step wall, reducing the difficulty of suction and boundary layer stripping of the large-scale separation zone, thereby further reducing the self-starting Mach number of the intake duct.

[0042] According to one aspect of the present invention, the present invention reduces the self-starting Mach number of the intake manifold while taking into account the performance of the intake manifold after startup, thereby reducing the flow loss at the design point. Attached Figure Description

[0043] Figure 1 This is a flowchart illustrating the design method of a rear step venting groove for a binary hypersonic inlet according to an embodiment of the present invention.

[0044] Figure 2 This is a schematic diagram of a two-dimensional air intake configuration according to an embodiment of the present invention;

[0045] Figure 3 This is a schematic diagram of the slotting position and tilt angle of the venting groove according to an embodiment of the present invention.

[0046] Figure 4 This is a schematic diagram of the rear step structure of the venting groove according to one embodiment of the present invention;

[0047] Figure 5 yes Figure 4 A magnified view of position A in the middle;

[0048] Figure 6 This is a schematic diagram showing the connection between the rear step structure of the last venting groove and the compression wall surface according to an embodiment of the present invention.

[0049] Figure 7 This is a schematic diagram of a binary hypersonic inlet structure generated by a design method according to an embodiment of the present invention. Detailed Implementation

[0050] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0051] In describing embodiments of the present invention, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer" express orientations or positional relationships based on the orientations or positional relationships shown in the relevant drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the above terms should not be construed as limitations on the present invention.

[0052] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. The embodiments cannot be described in detail here, but the embodiments of the present invention are not limited to the following embodiments.

[0053] like Figure 1 As shown, according to one embodiment of the present invention, a design method for a rear stepped vent groove of a two-dimensional hypersonic inlet includes the following steps:

[0054] S1. Obtain the two-dimensional intake configuration; wherein, the two-dimensional intake configuration includes: the inner wall of the lip cover, the compression wall opposite to the inner wall of the lip cover, and the lip and throat formed by the inner wall of the lip cover and the compression wall;

[0055] S2. Based on the lip point at the lip opening position of the inner wall of the lip cover, obtain the first positioning point on the compression wall surface used to locate the initial position of the venting groove;

[0056] S3. Starting from the first positioning point, arrange the second positioning points at preset distances on both sides of the first positioning point;

[0057] S4. Based on the first positioning point and the second positioning point, generate multiple venting grooves with a preset width and a preset tilt angle, respectively;

[0058] S5. A rear step structure is provided on the rear side of the venting groove along the direction from the lip to the throat.

[0059] like Figure 2 As shown, according to one embodiment of the present invention, in step S1, the obtained two-dimensional intake configuration can be a known configuration. For ease of description below, an example of a two-dimensional intake configuration is provided. In this configuration, the inner wall of the lip cover is horizontally arranged, and the compression wall is inclined relative to the inner wall of the lip cover, thereby forming a two-dimensional intake configuration with a large lip and a small throat. In this embodiment, the inclination angle of the compression wall relative to the inner wall of the lip cover can be set to 6.72°. It should be noted that the above-described two-dimensional intake configuration is only an example. In specific applications of this solution, the corresponding venting groove structure can be set based on the actual two-dimensional intake configuration.

[0060] like Figure 2 As shown, to further describe the two-dimensional intake configuration of this embodiment in detail, line 1 represents the compression wall surface, line 2 represents the inner wall surface of the lip cover, point 3 represents the lip opening point of the inner wall surface of the lip cover at the lip opening position, point 4 represents the intersection point of the inner wall surface of the lip cover and the subsequent throat, and point 5 represents the intersection point of the compression wall surface and the subsequent throat. It should be noted that the intake design often considers the integrated design of the forebody / intake duct, and the length of the compression wall surface of the intake duct meets the design requirements of the venting groove; therefore, the length of line 1 is not specifically described.

[0061] like Figure 2 As shown, according to one embodiment of the present invention, in step S2, the step of obtaining the first positioning point on the compression wall surface for positioning the initial position of the vent groove based on the lip point at the lip opening position of the inner wall surface of the lip cover, the first positioning point is the projection point of the lip point on the compression wall surface, that is, drawing a perpendicular line from point 3 to the compression wall surface, and the intersection of the obtained perpendicular line and the compression wall surface is the first positioning point. Figure 2 Midpoint 6.

[0062] In this embodiment, to accurately obtain the position of the first positioning point, it is also necessary to determine the position of the lip point. In this embodiment, the positions of the lip point and the first positioning point are obtained based on the position of the throat. Specifically, at the position of the throat, the distance between the line connecting points 4 and 5 is H. th Therefore, at the lip position, the distance between the line connecting points 3 and 6 is 2.53H. th This allows for the accurate determination of the lip point and the first positioning point. In this embodiment, the ratio between the distance between the line connecting points 4 and 5 and the distance between the line connecting points 3 and 6 can be set to other values, specifically adjusted adaptively based on the actual intake configuration.

[0063] like Figure 3 As shown, according to one embodiment of the present invention, in step S3, taking the first positioning point as the starting point, in the step of arranging the second positioning points at a preset distance on both sides of the first positioning point, the second positioning points are respectively set on the opposite sides (i.e. the front and rear sides) of the first positioning point along the direction from the lip to the throat. In the step of setting the second positioning points, it is necessary to further determine the length of the compression wall between the first positioning point and the second positioning point. If the length of the compression wall between the first positioning point and the second positioning point meets the preset distance (i.e., the length of the compression wall is equal to the preset distance), then the arranged second positioning points are retained.

[0064] If the conditions are not met, the second positioning point is rearranged so that the length of the compressed wall between adjacent positioning points is equal to the preset distance.

[0065] By comparing the length of the compressed wall surface with the preset distance, the position of the positioning point can be determined more accurately, making it applicable to different types of compressed wall surfaces. For example, when the compressed wall surface is planar, the distance between adjacent positioning points is the length of the compressed wall surface. When the compressed wall surface is curved, the distance between adjacent positioning points is different from the length of the compressed wall surface. Therefore, it is necessary to further adjust the position of the second positioning point so that the length of the compressed wall surface between adjacent positioning points meets the preset distance, thereby ensuring the applicability of the design method of the present invention on curved compressed wall surfaces.

[0066] Therefore, the preset distance used in step S3 can also be understood as the distance between adjacent positioning points along the compression wall.

[0067] In this embodiment, the preset distance satisfies: L = dH0, where L represents the preset distance and H0 represents the standard length, i.e., the distance between the first positioning point and the lip point. Figure 3 In H0), 0.50≤d≤2.00. Wherein, Figure 3 In this context, L1 represents the distance between the first positioning point and the adjacent second positioning point on the front side. Figure 3 L2 represents the distance between the first positioning point and the adjacent second positioning point on the rear side.

[0068] In this embodiment, the number of second positioning points can be set to one or more on the front side of the first positioning point, and the compression wall length between adjacent second positioning points must also meet the aforementioned requirements. Correspondingly, the number of second positioning points can be set to one or more on the rear side of the first positioning point, and the compression wall length between adjacent second positioning points must also meet the aforementioned requirements.

[0069] To facilitate the explanation of the present invention, an example is given in which a second positioning point is set in front of the first positioning point and a second positioning point is set in behind the first positioning point.

[0070] like Figure 3 As shown, in this embodiment, based on the lip point (i.e. Figure 3 Midpoint 3) obtains the corresponding first positioning point (i.e. Figure 3 Midpoint 6), and then, at the first positioning point (i.e. Figure 3 Based on the midpoint 6), at a preset distance, at the first positioning point (i.e. Figure 3 The corresponding second positioning point (i.e., 6) can be determined by looking in the direction before and after the midpoint. Figure 3(Midpoints 7 and 8). As mentioned earlier, the number of second positioning points can be adjusted. Therefore, if multiple second positioning points are set, the position of the next second positioning point is obtained by using the current second positioning point and a preset distance. In this embodiment, since the compressed wall surface used is planar, the length of the compressed wall surface between adjacent positioning points meets the preset distance, thereby retaining the obtained second positioning points.

[0071] like Figure 3 As shown, according to one embodiment of the present invention, in step S4, where multiple venting grooves with intervals are generated based on the first positioning point and the second positioning point with a preset width and a preset tilt angle, the first positioning point and the second positioning point are respectively the midpoints of the corresponding venting grooves in the width direction. In this embodiment, as the venting groove extends, its width remains constant. Furthermore, since the multiple positioning points are all located on the compression wall surface, and the opening of the venting groove is also located on the compression wall surface, the position of the venting groove can be accurately located by using the positioning point as the midpoint of the width direction of the venting groove (i.e., the midpoint of the venting groove opening). Furthermore, based on the determined opening position, the corresponding venting groove can be formed by extending based on the preset width and the preset tilt angle. In this embodiment, the tilt direction of the venting groove is clockwise. Furthermore, based on the two second positioning points and one first positioning point, three venting slots can be generated accordingly, which are represented from front to back as venting slot 9, venting slot 10, and venting slot 11, respectively. In this embodiment, multiple venting slots can be generated simultaneously, or venting slot 10 can be generated directly based on obtaining the first positioning point, and venting slot 9 and venting slot 11 can be generated directly based on obtaining the second positioning point.

[0072] In this embodiment, the preset width satisfies: D = eH0, where D represents the preset width, H0 represents the standard length, and 0.01 ≤ e ≤ 0.10; the preset tilt angle satisfies: 90° < θ < 180°.

[0073] It should be noted that only the following are selected in this article. Figure 1 The two-dimensional intake configuration shown is used to illustrate the present invention, but does not mean that the present invention is limited to this intake configuration.

[0074] It should be noted that, for the sake of convenience in describing the content of this invention, the length of the venting groove and the outlet structure, which are unrelated to this invention, have been simplified. This does not mean that this invention is limited to these aspects. Figure 3 The length of the venting channel and the outlet configuration are shown.

[0075] like Figure 3As shown, according to one embodiment of the present invention, in step S4, the width and tilt angle of the generated multiple venting grooves are independent of each other. That is, the width and tilt angle of the multiple venting grooves can be different or the same, and the values ​​can be selectively optimized according to the actual working conditions of the intake duct. Figure 3 The widths D1, D2, and D3 and the tilt angles θ1, θ2, and θ3 of the three venting grooves can be different or the same.

[0076] Combination Figure 4 , Figure 5 , Figure 6 , Figure 7 As shown, according to one embodiment of the present invention, in step S5, in the step of setting a rear step structure on the rear side of the venting groove, the rear step structure includes: a first smooth transition surface and an inclined extension surface.

[0077] In this embodiment, one end of the inclined extension surface is connected to the compression wall surface, and the other end is recessed and extends inclinedly towards the rear wall surface of the venting groove; the first smooth transition surface is used to connect the rear wall surface of the venting groove and the inclined extension surface.

[0078] Combination Figure 4 , Figure 5 , Figure 6 , Figure 7 As shown, according to one embodiment of the present invention, step S5, which involves providing a rear step structure on the rear side of the venting groove along the direction from the lip to the throat interface, includes:

[0079] S51. Determine the first boundary point of the rear step structure on the rear wall surface of the venting groove, and determine the second boundary point of the rear step structure on the compression wall surface.

[0080] S52. Determine the shape and parameters of the first smooth transition surface, and use the tangency of the first smooth transition surface with the rear wall of the venting groove at the first boundary point as the first constraint, and the tangency of the inclined extension surface with the first smooth transition surface as the second constraint, to generate the first smooth transition surface and the inclined extension surface.

[0081] Combination Figure 4 , Figure 5 As shown, according to one embodiment of the present invention, in step S51, in the step of determining the first boundary point of the rear step structure on the rear wall surface of the venting groove, the point on the rear wall surface is projected onto the compression wall surface and a first projection distance is obtained. It is determined whether the first projection distance satisfies the first preset length. If it does, the current point is taken as the first boundary point. In this embodiment, for ease of explanation, the first positioning point (i.e. Figure 3 The venting groove corresponding to midpoint 6) (i.e. Figure 3The description will focus on the venting groove 10. Specifically, any point on the rear wall of the venting groove 10 (i.e.,...) Figure 5 Midpoint 12), the selected point is projected onto the compression wall surface (where the projection on the compression wall surface is...). Figure 5 Midpoint 13 is indicated) and the first projected distance is obtained. The first projected distance is compared with the first preset length. If the conditions are met, the point is selected (i.e. Figure 5 Midpoint 12) serves as the transition surface with the first smooth transition surface (i.e. Figure 5 The centerline 14 indicates the starting point of the connection. In this embodiment, the first smooth transition surface is connected to the rear wall surface of the venting groove in a tangential manner. At this time, the selected point on the rear wall surface (i.e. Figure 5 Midpoint 12) is the tangent point. In this embodiment, the first preset length satisfies: H1 = bH0, where H1 represents the first preset length, H0 represents the standard length, and 0.05 ≤ b ≤ 0.10.

[0082] Combination Figure 4 , Figure 5 , Figure 6 , Figure 7 As shown, according to one embodiment of the present invention, step S51, in which the second boundary point of the rear step structure is determined on the compressed wall surface, includes:

[0083] Determine if the venting groove is the last one by following the direction from the lips to the throat;

[0084] If not, then the intersection of the front wall and the compression wall of the subsequent venting groove is taken as the second boundary point of the rear step structure of the previous venting groove; in this embodiment, the first positioning point (i.e. Figure 3 The venting groove corresponding to midpoint 6) (i.e. Figure 3 The description of the venting tank 10 is as follows. Figure 4 As shown, along the direction from the lips to the throat, if the venting groove corresponding to the first positioning point is not the last one, then the next venting groove (i.e. Figure 4 The intersection of the front wall of the venting trough 11 and the compression wall (i.e. Figure 4 Midpoint 17) serves as the second boundary point of the rear step structure of the preceding venting groove;

[0085] If so, the intersection of the front wall and the compression wall of the current venting groove is used as a reference point, and the second boundary point of the rear step structure of the current venting groove is obtained on the compression wall using the reference point and the second preset length. In this embodiment, along the direction from the lip to the throat, the second positioning point (i.e., the second positioning point behind the first positioning point) is used. Figure 3 The venting groove corresponding to midpoint 8) (i.e. Figure 3 , Figure 4 Taking the venting tank 11 in the middle as an example, the explanation is as follows: Figure 4 As shown, the last venting tank (i.e. Figure 4 The intersection of the front wall of the venting trough 11 and the compression wall (i.e. Figure 4 Midpoint 17) serves as the reference point for obtaining the second boundary point of the rear step structure of the last venting groove. Based on this reference point and the second preset length, the second boundary point of the rear step structure of the current venting groove (i.e., Figure 4 Midpoint 18); In this embodiment, the second preset length satisfies: H2 = fH0, where H2 represents the second preset length, H0 represents the standard length, and 0.50 ≤ f ≤ 2.00.

[0086] Based on the first and second boundary points obtained above, the corresponding rear step structure can be generated. Specifically, based on the determined shape and parameters of the first smooth transition surface, and based on the first and second constraints, the first smooth transition surface (i.e., ...) can be completely generated. Figure 5 Line 14 in the middle) and the inclined extension surface (i.e. Figure 5 Line 16 and Figure 6 In this embodiment, the inclined extension surface is also tangent to the first smooth transition surface (wherein the tangent point between the inclined extension surface and the first smooth transition surface is...). Figure 5 Point 15). In this embodiment, in step S52, in the step of determining the shape and parameters of the first smooth transition surface, the first smooth transition surface adopts an arc surface, and its radius satisfies: R1=aH0, where 0.05≤a≤0.10.

[0087] Combination Figure 6 and Figure 7 As shown, according to one embodiment of the present invention, in step S52, in the step of generating the first smooth transition surface and the inclined extension surface, if the venting groove is the last one along the direction from the lip to the throat, a second smooth transition surface is provided between the connection position of the rear step structure of the venting groove and the compression wall surface. Specifically, see... Figure 6 As shown, on the inclined extension surface of the rear step structure of the last venting groove (i.e., venting groove 11) Figure 6 Centerline 19) and compression wall (i.e. Figure 6 The centerline 1) is connected to the inclined extension surface (i.e.) by setting them respectively. Figure 6 Centerline 19) and compression wall (i.e. Figure 6 The second smooth transition surface tangent to the centerline 1) (i.e. Figure 6 (Middle line 20).

[0088] In this embodiment, in step S52, the second smooth transition surface is an arc surface, which is tangent to the inclined extension surface and the compression wall surface respectively, and its radius satisfies: R2=cH0, where 0.10≤c≤0.15.

[0089] The above description is merely an example of a specific solution of the present invention. For any devices and structures not described in detail herein, it should be understood that they are implemented using common devices and methods already available in the art.

[0090] The above description is merely one embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the invention by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A design method for a stepped vent groove behind a two-dimensional hypersonic inlet, characterized in that, Includes the following steps: S1. Obtain a two-dimensional air intake configuration; wherein, the two-dimensional air intake configuration includes: an inner wall surface of a lip cover, a compression wall surface opposite to the inner wall surface of the lip cover, and a lip and throat formed by the inner wall surface of the lip cover and the compression wall surface; S2. Based on the lip point at the lip opening position of the inner wall of the lip cover, obtain the first positioning point on the compression wall surface used to locate the initial position of the venting groove; S3. Taking the first positioning point as the starting point, arrange the second positioning points at a preset distance on both sides of the first positioning point; S4. Based on the first positioning point and the second positioning point, generate multiple venting grooves with a preset width and a preset tilt angle, respectively; S5. A rear step structure is provided on the rear side of the venting groove along the direction from the lip to the throat, wherein the rear step structure includes: a first smooth transition surface and an inclined extension surface; One end of the inclined extension surface is connected to the compression wall surface, and the other end is sunken and extends inclinedly towards the rear wall surface of the venting groove. The first smooth transition surface is used to connect the rear wall surface of the venting groove and the inclined extension surface; Then step S5 includes: S51. Determine the first boundary point of the rear step structure on the rear wall surface of the venting groove, and determine the second boundary point of the rear step structure on the compression wall surface; wherein, the point on the rear wall surface is projected onto the compression wall surface and a first projection distance is obtained, and it is determined whether the first projection distance satisfies a first preset length. If it does, the current point is taken as the first boundary point. Determine whether the venting groove is the last one along the direction from the lip to the throat; If not, then the intersection of the front wall surface of the next venting groove and the compression wall surface shall be taken as the second boundary point of the rear step structure of the previous venting groove. If so, the intersection of the front wall of the venting groove and the compression wall is used as the reference point, and the second boundary point of the rear step structure of the venting groove is obtained on the compression wall using the reference point and the second preset length. S52. Determine the shape and parameters of the first smooth transition surface, and use the tangency of the first smooth transition surface with the rear wall of the venting groove at the first boundary point as the first constraint, and the tangency of the inclined extension surface with the first smooth transition surface as the second constraint, to generate the first smooth transition surface and the inclined extension surface.

2. The design method according to claim 1, characterized in that, In step S2, the first positioning point is the projection point of the lip point on the compression wall surface.

3. The design method according to claim 2, characterized in that, In step S3, in the step of arranging second positioning points at a preset distance on both sides of the first positioning point, it is determined whether the length of the compressed wall between adjacent positioning points meets the preset distance. If it does, the arranged second positioning points are retained. If the condition is not met, the second positioning point is rearranged so that the length of the compressed wall between adjacent positioning points is equal to the preset distance.

4. The design method according to claim 3, characterized in that, In step S4, where multiple venting slots with intervals are generated based on the first positioning point and the second positioning point with a preset width and a preset tilt angle, the first positioning point and the second positioning point are respectively the midpoints of the corresponding venting slots in the width direction.

5. The design method according to claim 4, characterized in that, In step S4, the width and tilt angle of the generated multiple venting grooves are independent of each other.

6. The design method according to claim 5, characterized in that, In step S3, the preset distance satisfies: L=dH0, where L represents the preset distance and H0 represents the standard length, i.e., the distance between the first positioning point and the lip point, 0.50≤d≤2.00; In step S4, the preset width satisfies: D = eH0, where D represents the preset width, H0 represents the standard length, and 0.01 ≤ e ≤ 0.10; The preset tilt angle satisfies: 90° < θ < 180°; In step S51, the first preset length satisfies: H1=bH0, where H1 represents the first preset length, H0 represents the standard length, and 0.05≤b≤0.10; The second preset length satisfies: H2=fH0, where H2 represents the second preset length, H0 represents the standard length, and 0.50≤f≤2.

00.

7. The design method according to claim 6, characterized in that, In step S52, during the step of generating the first smooth transition surface and the inclined extension surface, if the venting groove is the last one along the direction from the lip to the throat, a second smooth transition surface is provided between the connection position of the rear step structure of the venting groove and the compression wall surface. In step S52, in the step of determining the shape and parameters of the first smooth transition surface, the first smooth transition surface is an arc surface, and its radius satisfies: R1=aH0, where 0.05≤a≤0.10; The second smooth transition surface is an arc surface, which is tangent to the inclined extension surface and the compression wall surface respectively. The radius of the second smooth transition surface satisfies: R2=cH0, where 0.10≤c≤0.15.

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