Single-degree-of-freedom steplessly adjustable TBCC inlet duct flow control method and device

Abstract

The present invention relates to the field of TBCC engine inlet duct design, and specifically to a single-degree-of-freedom steplessly adjustable TBCC inlet duct flow control method and device, which comprises a first-stage fixed shock wave ramp, a second-stage rotating shock wave ramp, and a third-stage telescopic shock wave ramp connected in sequence along the incoming flow direction, wherein the connection point B of the second-stage rotating shock wave ramp and the third-stage telescopic shock wave ramp rotates around point A, and the position of point B is determined by the profile contour line of the upper surface when the curved slider moves left and right. The control method is single-degree-of-freedom adjustment, that is, only one degree of freedom of the displacement of the left and right adjustment mechanisms needs to be controlled to simultaneously change the positions of point B and point C, thereby adjusting the external compression profile of the inlet duct. The present invention can realize the control of the incoming flow, so as to efficiently provide air with a certain pressure, temperature, speed and flow rate to the compressor of a turbine engine or the combustion chamber of a ramjet engine, thereby filling a part of the blank in the field of TBCC inlet ducts.

Description

Technical Field

[0001] The present invention relates to the field of TBCC engine intake duct design, and in particular to a single-degree-of-freedom steplessly adjustable TBCC intake duct flow channel control method and device. Background Art

[0002] In order to meet the requirements of hypersonic aircraft for horizontal takeoff and landing at conventional airports, wide speed range and large airspace, the turbine-based combined cycle (TBCC) engine is currently a more feasible technical solution. It has the advantages of both turbine engines and ramjet engines and meets the needs of hypersonic aircraft. Among them, the TBCC inlet is an important component of the TBCC engine. Its main task is to decelerate and pressurize the incoming flow, provide a high-quality flow field to the engine, and adjust the flow channel to meet the performance requirements of the turbine and ramjet engines working alone and during the smooth transition between the two. In order to ensure the wide speed range of the TBCC engine, the TBCC inlet should have a flow channel adjustment function, but due to the limitation of structural strength and the complexity of the adjustment mechanism, the inlet has fewer adjustable parts, which makes the overall aerodynamic performance of the inlet poor.

[0003] In order to facilitate the design of the flow passage adjustment mechanism, the binary configuration is currently used to design the combined inlet. Affected by the synchronization complexity and safety of the actuating mechanism, the single-degree-of-freedom flow passage adjustment mechanism is the mainstream method of the current combined inlet design. However, this limits the number of adjustable components of the combined inlet to a certain extent, and ultimately forces the inlet to sacrifice overall performance to meet the working requirements of a wide speed range. For example, Yuan Huacheng's team designed a single-degree-of-freedom adjustment mechanism to control the second-stage shock wave and throat section; Tan Huijun's team developed a binary combined inlet adjustment mechanism to achieve inlet control, but the adjustable components are basically the same as Yuan Huacheng's team; according to public documents, the inlet configurations designed by Shenyang Aerodynamics Research Institute, Shenyang Aircraft Design Institute, and China Aero Engine Sichuan Gas Turbine Research Institute are basically adjusted by a single-degree-of-freedom actuating mechanism to adjust the last shock wave and throat height, and the inlet performance is greatly reduced compared to the fixed geometry inlet, such as the total pressure recovery coefficient of the ramjet mode is basically reduced by more than 0.05.

[0004] In summary, it is difficult to balance the contradiction between the number of adjustable components and the performance of the combined air intake duct designed by the traditional method. In order to further improve the compatibility of the TBCC air intake duct with the engine, it is necessary to cleverly design the adjustable mechanism to achieve single-degree-of-freedom control of multiple adjustable components to improve the aerodynamic performance of the air intake duct. The present invention provides a design method for a single-degree-of-freedom steplessly adjustable TBCC air intake duct flow control mechanism, which can effectively solve the shortcomings of the traditional design method and is conducive to further improving the overall aerodynamic performance of the air intake duct. Summary of the invention

[0005] To solve the above problems, the present invention provides a single-degree-of-freedom steplessly adjustable TBCC inlet duct flow control method, so as to process incoming flows with different Mach numbers and efficiently provide a high-quality flow field to the engine.

[0006] In order to achieve the above object, the technical solution of the present invention is as follows:

[0007] The first object of the present invention is to provide a single-degree-of-freedom stepless adjustable TBCC inlet duct flow control method, which comprises: a first-stage fixed shock wave inclined plate 1, a second-stage rotating shock wave inclined plate 2, and a third-stage telescopic shock wave inclined plate 3 connected in sequence along the incoming flow direction, setting: the intersection of the first-stage fixed shock wave inclined plate 1 and the forebody at the front of the inlet duct is set as the origin, the incoming flow direction along the inlet duct is the positive x direction, and the y direction is perpendicular to the incoming flow direction of the inlet duct, and a coordinate system is established;

[0008] The adjustable arc plate 11 is hinged at the rear of the third-stage telescopic shock wave inclined plate 3; the adjustable lip cover 4 is arranged above the adjustable arc plate 11, and the first-stage fixed shock wave inclined plate 1, the second-stage rotating shock wave inclined plate 2, the third-stage telescopic shock wave inclined plate 3, the upper surface of the adjustable arc plate 11 and the lower surface of the adjustable lip cover 4 form an air inlet profile;

[0009] The two ends of the first-stage fixed shock wave inclined plate 1 are fixed, the connection point A of the second-stage rotating shock wave inclined plate 2 and the first-stage fixed shock wave inclined plate 1 is fixed, and the connection point B of the second-stage rotating shock wave inclined plate 2 and the third-stage telescopic shock wave inclined plate 3 rotates around point A, and point B is movably overlapped on the upper surface of the curved slider 12. The position of point B is determined by the profile contour line of the upper surface when the curved slider 12 moves left and right.

[0010] Point C is the connection point between the adjustable circular arc plate 11 and the third-stage telescopic shock wave inclined plate 3. The BC of the third-stage telescopic shock wave inclined plate 3 is a straight line segment.

[0011] It also includes a control device, which includes a curved slider 12 and a left-right adjustment mechanism for driving the curved slider 12 to move left and right;

[0012] This control method is a single-degree-of-freedom adjustment, that is, only one degree of freedom of the displacement of the left and right adjustment mechanisms needs to be controlled to simultaneously change the positions of point B and point C, thereby adjusting the external compression profile of the air inlet duct. By adjusting the positions of point B and point C, it is ensured that BC and the adjustable arc plate 11 are tangent at point C.

[0013] As a preferred embodiment, the control device includes a curved slider 12, a slider 5, a straight rod 10, and the left and right adjustment mechanism is a telescopic screw 9;

[0014] The curved slider 12 is connected to the telescopic screw 9 on one side along the positive x direction. A straight rod 10 is provided between the upper part of the curved slider 12 and the adjustable arc plate 11. The top of the straight rod 10 is hinged to the bottom of the adjustable arc plate 11. The bottom of the straight rod 10 is movably arranged on the curved slider 12. The slide groove 13 is located on the adjustable arc plate 11. The shape and curvature of the slide groove 13 are consistent with the curvature of the adjustable arc plate 11. The slider 5 is slidably connected in the slide groove 13.

[0015] The curved slider 12 is controlled to move forward and backward by rotating the telescopic screw 9 , thereby controlling the straight rod 10 to move up and down, and the intersection B of the second-stage rotating shock wave inclined plate 2 and the third-stage telescopic shock wave inclined plate 3 to move along the upper surface of the curved slider 12 .

[0016] As a preferred embodiment, the y-direction limit block 14 is sleeved on the outside of the straight rod 10 to limit the straight rod 10 to move only in the y-direction.

[0017] As a preferred embodiment, the adjustable circular arc plate 11 includes an adjustable circular arc segment 15 which can be retracted below the adjustable circular arc plate 11 and whose left boundary is flush with the third-stage telescopic shock wave inclined plate 3 when retracted.

[0018] As a preferred method, the upper and lower positions of the straight rod 10 are determined by the profile of the curved slider 12; after the height of the straight rod 10 is increased, it drives the adjustable arc plate 11 upward, and makes the slider 5 move in the slide groove 13 along the slide groove in the negative x direction, and a gap is generated in the y direction between the third-stage telescopic shock wave inclined plate 3 and the adjustable arc plate 11, the slide groove 13 is located on the adjustable arc segment 15 of the adjustable arc plate 11, and the slider 5 is inserted in the slide groove 13 of the adjustable arc segment 15. The slider 5 slides to the left and drives the adjustable arc segment 15 to move to the left to compensate for the gap between the adjustable arc plate 11 and the third-stage telescopic shock wave inclined plate 3, thereby ensuring that BC is tangent to the adjustable arc plate 11.

[0019] As a preferred embodiment, one end of the splitter plate 6 overlaps the adjustable arc plate 11 to close the turbine channel; or it rotates around the splitter plate axis 16 to the upper wall surface to close the stamping channel.

[0020] As a preferred embodiment, the intersection of the lower end of the straight rod and the curved slider 12 is point I; the profile of the curved slider 12 is fitted by a formula.

[0021] As a preferred method, the capture area A0 is obtained from the incoming flow Mach number, flight altitude, and capture flow rate, and then the capture section width and height, i.e., the y coordinate of the lip point, are obtained by combining the inlet duct aspect ratio; the angles of each shock wave are further determined by the optimal wave system configuration relationship of the design point, and then the length L1 of the first-stage fixed shock wave ramp 1 and the length L2 of the second-stage rotating shock wave ramp 2 are determined according to the capture section height and the shock wave angles of each stage through geometric relationships; the inclination angle θ1 of the first-stage fixed shock wave ramp 1 is determined by the shock wave relationship, and the first-stage fixed shock wave ramp 1 and the second-stage rotating shock wave ramp 2 intersect at a fixed point A, and the coordinate expression is:

[0022] ,

[0023] The second-stage rotating shock wave inclined plate 2: is controlled by external force to rotate around point A, and the inclination angle θ2 changes with the incoming flow Mach number. The specific adjustment rule is determined by the designer according to the aerodynamic performance under different incoming flow Mach numbers. θ2 is the horizontal angle of the second-stage rotating shock wave inclined plate; the second-stage rotating shock wave inclined plate 2 intersects with the third-stage telescopic shock wave inclined plate 3 at point B. The coordinates of point B change with the second-stage rotating shock wave inclined plate. The specific expression is: ;

[0024] According to the geometric relationship, the inclination angle θ2 of the second-stage rotating shock wave inclined plate 2 is determined according to the length of the third-stage telescopic shock wave inclined plate 3, the radius R of the arc plate and the y coordinate H of the right end point of the arc plate. The relationship of θ2 is as follows:

[0025] (1)

[0026] Wherein, θ3 is the horizontal angle of the third-stage telescopic shock wave ramp 3;

[0027] The third-stage telescopic shock wave inclined plate 3: after receiving external force, the length L3 and the inclination angle θ3 are adjusted by the y coordinate H of the right end point of the adjustable arc plate 11 and the coordinate of point B to determine the angle and length of the third-stage telescopic shock wave inclined plate 3, θ3 is the horizontal angle of the third-stage telescopic shock wave inclined plate 3, and the relationship between the length L3 and the inclination angle θ3 with the length L1 and L2, the inclination angles θ1 and θ2, the radius R of the adjustable arc plate 11 and the y coordinate H of the right end point of the adjustable arc plate 11 is established by geometric relationship as follows:

[0028]

[0029] Further, θ3 is obtained according to formula (2) based on H, and the length L3 is further determined according to formula (3).

[0030] As a preferred method, under different incoming flow Mach numbers, the values ​​of θ1, θ2, θ3, L1, L2, L3, H, and the coordinates of points A, B, C, and I are determined with the profile arrangement that best suits the working conditions;

[0031] The coordinates of points B and I are determined through multiple tests, and the coordinates are interpolated to fit the forming line to determine the shape of the curved slider 12;

[0032] The shape fitting process of the curved slider 12 is as follows:

[0033] The coordinates of point A, point B, point I, θ1, θ2, θ3, L1, L2, L3, and H are determined by the following formula:

[0034] (1.1)

[0035] ;

[0036] The following relationship can be obtained from the above formula:

[0037] ;

[0038] The coordinates of points A, B, and C can also be obtained:

[0039]

[0040] set up I The distance between the point and the x-axis is Δh, and the distance between the point and the y-axis is l , so I The coordinates of a point can be expressed as: I (l, Δh) ;

[0041] When the right curved slider moves, it will cause B point changes, so θ 2 will also change accordingly; at different Mach numbers, the lateral movement distance of the curved slider is Δ x , B The coordinates of the points are ; Fit the coordinates of points B and I under different working conditions to obtain the profile, and then make a curved slider based on the profile;

[0042] Wherein, L1 is the length of the first-stage fixed shock wave inclined plate 1; L2 is the length of the second-stage rotating shock wave inclined plate 2; L3 is the length of the third-stage telescopic shock wave inclined plate 3; θ1 is the angle between the first-stage fixed shock wave inclined plate 1 and the x-axis; θ2 is the horizontal angle of the second-stage rotating shock wave inclined plate 2; θ3 is the horizontal angle of the third-stage telescopic shock wave inclined plate 3; α1 is the angle between the auxiliary line perpendicular to the third-stage telescopic shock wave inclined plate 3 and the horizontal line passing through point C; α2 is the angle between the chord length K and the horizontal line passing through point C. The angle between the horizontal line; W is the distance between point A and the y-axis; M is the distance between point A and the x-axis; E is the distance between point B and the y-axis minus W; N is the distance between point B and the x-axis minus M; P is the distance between point C and the y-axis minus W and E; Q is the distance between point C and the x-axis minus M and N; K is the chord length of the arc plate; G is the distance between the horizontal line passing through point C and the right end point of the arc plate; H is the distance between the right end point of the arc plate and the x-axis; R is the radius of the arc; Δh is the ordinate of point I, l is the horizontal coordinate of point I;

[0043] Secondly, after obtaining the coordinates of points B and I, the curved slider profile is determined through Lagrange interpolation.

[0044] The second object of the present invention is to provide a single-degree-of-freedom stepless adjustable TBCC inlet duct flow control device, which is used in the above control method, and includes a first-stage fixed shock wave inclined plate 1, a second-stage rotating shock wave inclined plate 2, and a third-stage telescopic shock wave inclined plate 3 connected in sequence along the incoming flow direction, and it is set that: the intersection of the first-stage fixed shock wave inclined plate 1 and the forebody at the front of the inlet duct is taken as the origin, the direction of the inlet duct from the first-stage fixed shock wave inclined plate 1 to the second-stage rotating shock wave inclined plate 2 is taken as the positive x direction, and the normal direction away from the inlet duct is taken as the y axis, and a coordinate system is established;

[0045] The adjustable arc plate 11 is hinged at the rear of the third-stage telescopic shock wave inclined plate 3; the adjustable lip cover 4 is arranged above the adjustable arc plate 11, and the first-stage fixed shock wave inclined plate 1, the second-stage rotating shock wave inclined plate 2, the third-stage telescopic shock wave inclined plate 3, the adjustable arc plate 11, and the adjustable lip cover 4 together form the entire inlet flow channel;

[0046] The two ends of the first-stage fixed shock wave inclined plate 1 are fixed, the connection point A of the second-stage rotating shock wave inclined plate 2 and the first-stage fixed shock wave inclined plate 1 is fixed, and the connection point B of the second-stage rotating shock wave inclined plate 2 and the third-stage telescopic shock wave inclined plate 3 rotates around point A, and point B is movably overlapped on the upper surface of the curved slider 12. The position of point B is determined by the profile contour line of the upper surface when the curved slider 12 moves left and right.

[0047] Point C is the connection point between the adjustable circular arc plate 11 and the third-stage telescopic shock wave inclined plate 3. The BC of the third-stage telescopic shock wave inclined plate 3 is a straight line segment.

[0048] It also includes a control device; the control device includes a curved slider 12, a slider 5, a straight rod 10, and a telescopic screw 9 that drives the curved slider 12 to move left and right; the curved slider 12 is connected to the telescopic screw 9 on one side along the positive direction of x, and a straight rod 10 is provided between the upper part of the curved slider 12 and the adjustable circular arc plate 11, the top of the straight rod 10 is hinged to the bottom of the adjustable circular arc plate 11, and the bottom of the straight rod 10 is movably arranged on the curved slider 12, and the adjustable circular arc plate 11 includes an adjustable circular arc segment 15 that can be retracted below the adjustable circular arc plate 11 and whose left boundary is flush with point C; the chute 13 is located on the adjustable circular arc segment 15 of the adjustable circular arc plate 11, and the slider 5 is inserted into the chute 13 of the adjustable circular arc segment 15, and the shape and curvature of the chute 13 are consistent with the curvature of the adjustable circular arc plate 11; the slider 5 is slidably connected in the chute 13;

[0049] This control device is a single-degree-of-freedom adjustment, that is, only one degree of freedom of the displacement of the telescopic screw 9 needs to be controlled to simultaneously change the positions of point B and point C, thereby adjusting the external compression profile of the air inlet duct. By adjusting the positions of point B and point C, it is ensured that BC and the adjustable arc plate 11 are tangent at point C.

[0050] By using the above technical solution, the present invention has the following beneficial technical effects:

[0051] The single-degree-of-freedom steplessly adjustable TBCC inlet flow control method of the present invention can not only realize the control of the incoming flow, so as to efficiently provide air of a certain pressure, temperature, speed and flow rate to the compressor of a turbine engine or the combustion chamber of a ramjet engine, filling some gaps in the field of TBCC inlets, but also realize the control of the two-stage shock wave ramp and throat by controlling only one degree of freedom, providing a reference for more designs in the future. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 It is a simplified structural diagram of the single-degree-of-freedom steplessly adjustable TBCC inlet duct flow control method of the present invention;

[0053] Figure 2 It is a geometrically simplified diagram of the single-degree-of-freedom steplessly adjustable TBCC inlet duct flow control method of the present invention;

[0054] Figure 3 It is a stamping modal diagram of the single-degree-of-freedom steplessly adjustable TBCC inlet duct flow channel control method of the present invention;

[0055] Figure 4 It is a turbine modal diagram of the single-degree-of-freedom steplessly adjustable TBCC inlet duct flow control method of the present invention;

[0056] Figure 5 It is a design result diagram of the single-degree-of-freedom steplessly adjustable TBCC inlet duct flow control method of the present invention;

[0057] FIG6 (a) is a state diagram of the adjustable arc segment 15 compensating the gap between the adjustable arc plate 11 and the third-stage telescopic shock wave ramp plate 3;

[0058] FIG. 6( b ) is a diagram showing a state where the adjustable arc segment 15 is retracted inside the adjustable arc plate 11 .

[0059] Among them, 1 is the first-stage fixed shock wave inclined plate, 2 is the second-stage rotating shock wave inclined plate, 3 is the third-stage telescopic shock wave inclined plate, 4 is the adjustable lip cover, 5 is the slider, 6 is the diverter plate, 7 is the stamping channel, 8 is the turbine channel, 9 is the telescopic screw, 10 is the straight rod, 11 is the adjustable arc plate, 12 is the curved slider, 13 is the slide groove, 14 is the y-direction limit block, 15 is the adjustable arc segment, and 16 is the axis of the diverter plate.

[0060] L1 is the length of the first-stage fixed shock wave inclined plate 1; L2 is the length of the second-stage rotating shock wave inclined plate 2; L3 is the length of the third-stage telescopic shock wave inclined plate 3; θ1 is the angle between the first-stage fixed shock wave inclined plate 1 and the x-axis; θ2 is the horizontal angle of the second-stage rotating shock wave inclined plate 2; θ3 is the horizontal angle of the third-stage telescopic shock wave inclined plate 3; α1 is the angle between the auxiliary line perpendicular to the third-stage telescopic shock wave inclined plate 3 and the horizontal line passing through point C; α2 is the angle between the chord length K and the horizontal line passing through point C ; W is the distance between point A and the y-axis; M is the distance between point A and the x-axis; E is the distance between point B and the y-axis minus W; N is the distance between point B and the x-axis minus M; P is the distance between point C and the y-axis minus W and E; Q is the distance between point C and the x-axis minus M and N; K is the chord length of the arc plate; G is the distance between the horizontal line passing through point C and the right end point of the arc plate; H is the distance between the right end point of the arc plate and the x-axis; R is the radius of the arc; Δh is the ordinate of point I, and l is the abscissa of point I. DETAILED DESCRIPTION

[0061] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0062] The invention discloses a steplessly adjustable TBCC intake duct flow channel control method.

[0063] Example 1

[0064] like Figure 1As shown, this embodiment provides a single-degree-of-freedom stepless adjustable TBCC inlet duct flow control method, which includes a first-stage fixed shock wave inclined plate 1, a second-stage rotating shock wave inclined plate 2, and a third-stage telescopic shock wave inclined plate 3 connected in sequence along the incoming flow direction, and sets: the intersection of the first-stage fixed shock wave inclined plate 1 and the forerunner at the front of the inlet duct is set as the origin, the incoming flow direction along the inlet duct is the positive x direction, and the y direction is perpendicular to the incoming flow direction of the inlet duct, and a coordinate system is established;

[0065] The adjustable arc plate 11 is hinged at the rear of the third-stage telescopic shock wave inclined plate 3; the adjustable lip cover 4 is arranged above the adjustable arc plate 11, and the first-stage fixed shock wave inclined plate 1, the second-stage rotating shock wave inclined plate 2, the third-stage telescopic shock wave inclined plate 3, the upper surface of the adjustable arc plate 11 and the lower surface of the adjustable lip cover 4 form an air inlet profile;

[0066] The two ends of the first-stage fixed shock wave inclined plate 1 are fixed, the connection point A of the second-stage rotating shock wave inclined plate 2 and the first-stage fixed shock wave inclined plate 1 is fixed, and the connection point B of the second-stage rotating shock wave inclined plate 2 and the third-stage telescopic shock wave inclined plate 3 rotates around point A, and point B is movably overlapped on the upper surface of the curved slider 12. The position of point B is determined by the profile contour line of the upper surface when the curved slider 12 moves left and right.

[0067] Point C is the connection point between the adjustable circular arc plate 11 and the third-stage telescopic shock wave inclined plate 3. The BC of the third-stage telescopic shock wave inclined plate 3 is a straight line segment.

[0068] It also includes a control device, which includes a curved slider 12 and a left-right adjustment mechanism for driving the curved slider 12 to move left and right;

[0069] This control method is a single-degree-of-freedom adjustment, that is, only one degree of freedom of the displacement of the left and right adjustment mechanisms needs to be controlled to simultaneously change the positions of point B and point C, thereby adjusting the external compression profile of the air inlet duct. By adjusting the positions of point B and point C, it is ensured that BC and the adjustable arc plate 11 are tangent at point C.

[0070] The control device includes a curved slider 12, a slider 5, and a straight rod 10.

[0071] In this embodiment, the left-right adjustment mechanism is a telescopic screw 9; in other embodiments, the left-right adjustment mechanism can be: a worm gear, a screw drive, a hydraulic drive, etc., any mechanism that can move the curved slider 12 left and right.

[0072] The curved slider 12 is connected to the telescopic screw 9 on one side along the positive x direction. A straight rod 10 is provided between the upper part of the curved slider 12 and the adjustable arc plate 11. The top of the straight rod 10 is hinged to the bottom of the adjustable arc plate 11. The bottom of the straight rod 10 is movably arranged on the curved slider 12. The slide groove 13 is located on the adjustable arc plate 11. The shape and curvature of the slide groove 13 are consistent with the curvature of the adjustable arc plate 11. The slider 5 is slidably connected in the slide groove 13.

[0073] The curved slider 12 is controlled to move forward and backward by rotating the telescopic screw 9 , thereby controlling the straight rod 10 to move up and down, and the intersection B of the second-stage rotating shock wave inclined plate 2 and the third-stage telescopic shock wave inclined plate 3 to move along the upper surface of the curved slider 12 .

[0074] The y-direction limiting block 14 is sleeved on the outside of the straight rod 10 to limit the straight rod 10 to move only in the y-direction.

[0075] The adjustable arc plate 11 includes an adjustable arc segment 15 which can be retracted below the adjustable arc plate 11 and whose left edge is flush with the third-stage telescopic shock wave ramp plate 3 when retracted. FIG6( b ) is a state diagram of the adjustable arc segment 15 retracted inside the adjustable arc plate 11 .

[0076] The upper and lower positions of the straight rod 10 are determined by the profile of the curved slider 12; after the height of the straight rod 10 is increased, the adjustable arc plate 11 is driven upward, and the slider 5 moves in the slide groove 13 along the slide groove in the negative x direction, and a gap is generated between the third-stage telescopic shock wave inclined plate 3 and the adjustable arc plate 11 in the y direction. The slide groove 13 is located on the adjustable arc segment 15 of the adjustable arc plate 11, and the slider 5 is inserted in the slide groove 13 of the adjustable arc segment 15. The slider 5 slides to the left and drives the adjustable arc segment 15 to move to the left to compensate for the gap between the adjustable arc plate 11 and the third-stage telescopic shock wave inclined plate 3, thereby ensuring that BC is tangent to the adjustable arc plate 11. The state diagram of the adjustable arc segment 15 compensating the gap between the adjustable arc plate 11 and the third-stage telescopic shock wave inclined plate 3 is shown in Figure 6 (a).

[0077] When the straight rod 10 moves downward, the adjustable circular arc plate 11 also moves downward, and the adjustable circular arc segment 15 in the adjustable circular arc plate 11 slides to the right along the circular arc profile and shrinks inside the adjustable circular arc plate 11 .

[0078] One end of the splitter plate 6 overlaps the adjustable arc plate 11 to close the turbine channel; or rotates around the splitter plate axis 16 to the upper wall surface to close the stamping channel.

[0079] The intersection of the lower end of the straight rod and the curved slider 12 is point I; the profile of the curved slider 12 is fitted by the formula.

[0080] The capture area A0 is obtained from the incoming flow Mach number, flight altitude, and capture flow rate, and then combined with the inlet duct aspect ratio, the capture section width and height, i.e., the y coordinate of the lip point, can be obtained; the angles of each level of shock wave are further determined by the optimal wave system configuration relationship of the design point, and then the length L1 of the first-stage fixed shock wave ramp 1 and the length L2 of the second-stage rotating shock wave ramp 2 are determined according to the capture section height and the shock wave angles of each level through geometric relationships; the inclination angle θ1 of the first-stage fixed shock wave ramp 1 is determined by the shock wave relationship, and the first-stage fixed shock wave ramp 1 and the second-stage rotating shock wave ramp 2 intersect at the fixed point A, and the coordinate expression is:

[0081]

[0082] The second-stage rotating shock wave inclined plate 2: is controlled by external force to rotate around point A, and the inclination angle θ2 changes with the incoming flow Mach number. The specific adjustment rule is determined by the designer according to the aerodynamic performance under different incoming flow Mach numbers. θ2 is the horizontal angle of the second-stage rotating shock wave inclined plate 2; the second-stage rotating shock wave inclined plate 2 intersects with the third-stage telescopic shock wave inclined plate 3 at point B. The coordinates of point B change with the second-stage rotating shock wave inclined plate. The specific expression is:

[0083] According to the geometric relationship, the inclination angle θ2 of the second-stage rotating shock wave inclined plate 2 is determined according to the length of the third-stage telescopic shock wave inclined plate 3, the radius R of the arc plate and the y coordinate H of the right end point of the arc plate. The relationship of θ2 is as follows:

[0084] (1)

[0085] Wherein, θ3 is the horizontal angle of the third-stage telescopic shock wave ramp 3;

[0086] The third-stage telescopic shock wave inclined plate 3: the angle and length of the third-stage telescopic shock wave inclined plate 3 are determined by adjusting the length L3 and the inclination angle θ3 through the y coordinate H of the right end point of the adjustable arc plate and the coordinate of point B under external force, θ3 is the horizontal angle of the third-stage telescopic shock wave inclined plate 3, and the relationship between the length L3 and the inclination angle θ3 with the length L1 and L2, the inclination angles θ1 and θ2, the radius R of the adjustable arc plate and the y coordinate H of the right end point of the adjustable arc plate 11 is established by geometric relationship as follows:

[0087] (2)

[0088] (3)

[0089] Further, θ3 is obtained according to formula (2) based on H, and the length L3 is further determined according to formula (3).

[0090] Under different incoming flow Mach numbers, determine the values ​​of θ1, θ2, θ3, L1, L2, L3, H, and the coordinates of points A, B, C, and I with the profile layout that best suits the working conditions;

[0091] The coordinates of points B and I are determined through multiple tests, and the coordinates are interpolated to fit the forming line to determine the shape of the curved slider 12;

[0092] The shape fitting process of the curved slider 12 is as follows:

[0093] The coordinates of point A, point B, point I, θ1, θ2, θ3, L1, L2, L3, and H are determined by the following formula:

[0094] (1.1)

[0095]

[0096] The following relationship can be obtained from the above formula:

[0097]

[0098] The coordinates of points A, B, and C can also be obtained:

[0099]

[0100] set up I The distance between the point and the x-axis is Δ h , the distance from the y-axis is l , so I The coordinates of a point can be expressed as: I (l, Δh) ;

[0101] When the right curved slider moves, it will cause B point changes, so θ 2 will also change accordingly; at different Mach numbers, the lateral movement distance of the curved slider is Δ x , B The coordinates of the points are ; Fit the coordinates of points B and I under different working conditions to obtain the profile, and then make a curved slider based on the profile;

[0102] Wherein, L1 is the length of the first-stage fixed shock wave inclined plate 1; L2 is the length of the second-stage rotating shock wave inclined plate 2; L3 is the length of the third-stage telescopic shock wave inclined plate 3; θ1 is the angle between the first-stage fixed shock wave inclined plate 1 and the x-axis; θ2 is the horizontal angle of the second-stage rotating shock wave inclined plate 2; θ3 is the horizontal angle of the third-stage telescopic shock wave inclined plate 3; α1 is the angle between the auxiliary line perpendicular to the third-stage telescopic shock wave inclined plate 3 and the horizontal line passing through point C; α2 is the angle between the chord length K and the horizontal line passing through point C. The angle between the horizontal line; W is the distance between point A and the y-axis; M is the distance between point A and the x-axis; E is the distance between point B and the y-axis minus W; N is the distance between point B and the x-axis minus M; P is the distance between point C and the y-axis minus W and E; Q is the distance between point C and the x-axis minus M and N; K is the chord length of the arc plate; G is the distance between the horizontal line passing through point C and the right end point of the arc plate; H is the distance between the right end point of the arc plate and the x-axis; R is the radius of the arc; Δh is the ordinate of point I, l is the horizontal coordinate of point I.

[0103] Secondly, after obtaining the coordinates of points B and I, the curved slider profile is determined through Lagrange interpolation.

[0104] like Figure 1 As shown, the dotted line of the upper adjustable lip shield 4 in the figure represents the position change of the adjustable lip shield 4 before and after the movement. When the captured flow is insufficient, the adjustable lip shield 4 moves in the negative direction of the X-axis to achieve more captured flow. When the captured flow is too large, the adjustable lip shield 4 moves in the positive direction of the X-axis to reduce the captured flow. The dotted line of the third-stage telescopic shock wave inclined plate 3 below represents the omitted telescopic length of the third-stage telescopic shock wave inclined plate 3. When the straight rod 10 moves upward, it will be extended; when the straight rod 10 moves downward, it will be shortened.

[0105] like Figure 2 As shown, the dotted line of the upper adjustable lip shield 4 in the figure represents the position change of the adjustable lip shield 4 before and after the movement. When the captured flow is insufficient, the adjustable lip shield 4 moves in the negative direction of the X-axis to achieve more captured flow. When the captured flow is too large, the adjustable lip shield 4 moves in the positive direction of the X-axis to reduce the captured flow. The dotted line of the third-stage telescopic shock wave inclined plate 3 below represents the omitted telescopic length of the third-stage telescopic shock wave inclined plate 3. When the straight rod 10 moves upward, it will be extended; when the straight rod 10 moves downward, it will be shortened.

[0106] like Figure 3 As shown, the dotted line of the upper adjustable lip mask 4 in the figure represents the position change of the adjustable lip mask 4 before and after movement. When the captured flow is insufficient, the adjustable lip mask 4 moves in the negative direction of the X-axis to achieve more captured flow. When the captured flow is too large, the adjustable lip mask 4 moves in the positive direction of the X-axis to reduce the captured flow.

[0107] like Figure 4As shown, the dotted line of the upper adjustable lip mask 4 in the figure represents the position change of the adjustable lip mask 4 before and after movement. When the captured flow is insufficient, the adjustable lip mask 4 moves in the negative direction of the X-axis to achieve more captured flow. When the captured flow is too large, the adjustable lip mask 4 moves in the positive direction of the X-axis to reduce the captured flow.

[0108] The design result obtained by the single-degree-of-freedom stepless adjustable TBCC inlet duct flow control method of the present invention is shown in the figure below: Figure 5 shown.

[0109] Example 2

[0110] This embodiment provides a single-degree-of-freedom stepless adjustable TBCC inlet duct flow control device, which includes a first-stage fixed shock wave ramp 1, a second-stage rotating shock wave ramp 2, and a third-stage telescopic shock wave ramp 3 connected in sequence along the incoming flow direction, and sets: the intersection of the first-stage fixed shock wave ramp 1 and the forebody at the front of the inlet duct is set as the origin, the direction of the inlet duct from the first-stage fixed shock wave ramp 1 to the second-stage rotating shock wave ramp 2 is set as the positive x direction, and the normal direction away from the inlet duct is set as the y axis, and a coordinate system is established;

[0111] The adjustable arc plate 11 is hinged at the rear of the third-stage telescopic shock wave inclined plate 3; the adjustable lip cover 4 is arranged above the adjustable arc plate 11, and the first-stage fixed shock wave inclined plate 1, the second-stage rotating shock wave inclined plate 2, the third-stage telescopic shock wave inclined plate 3, the adjustable arc plate 11, and the adjustable lip cover 4 together form the entire inlet flow channel;

[0112] The two ends of the first-stage fixed shock wave inclined plate 1 are fixed, the connection point A of the second-stage rotating shock wave inclined plate 2 and the first-stage fixed shock wave inclined plate 1 is fixed, and the connection point B of the second-stage rotating shock wave inclined plate 2 and the third-stage telescopic shock wave inclined plate 3 rotates around point A, and point B is movably overlapped on the upper surface of the curved slider 12. The position of point B is determined by the profile contour line of the upper surface when the curved slider 12 moves left and right.

[0113] Point C is the connection point between the adjustable circular arc plate 11 and the third-stage telescopic shock wave inclined plate 3. The BC of the third-stage telescopic shock wave inclined plate 3 is a straight line segment.

[0114] It also includes a control device; the control device includes a curved slider 12, a slider 5, a straight rod 10, and a telescopic screw 9 that drives the curved slider 12 to move left and right; the curved slider 12 is connected to the telescopic screw 9 on one side along the positive direction of x, and a straight rod 10 is provided between the upper part of the curved slider 12 and the adjustable circular arc plate 11, the top of the straight rod 10 is hinged to the bottom of the adjustable circular arc plate 11, and the bottom of the straight rod 10 is movably arranged on the curved slider 12, and the adjustable circular arc plate 11 includes an adjustable circular arc segment 15 that can be retracted below the adjustable circular arc plate 11 and whose left boundary is flush with point C; the chute 13 is located on the adjustable circular arc segment 15 of the adjustable circular arc plate 11, and the slider 5 is inserted into the chute 13 of the adjustable circular arc segment 15, and the shape and curvature of the chute 13 are consistent with the curvature of the adjustable circular arc plate 11; the slider 5 is slidably connected in the chute 13;

[0115] This control device is a single-degree-of-freedom adjustment, that is, only one degree of freedom of the displacement of the telescopic screw 9 needs to be controlled to simultaneously change the positions of point B and point C, thereby adjusting the external compression profile of the air inlet duct. By adjusting the positions of point B and point C, it is ensured that BC and the adjustable arc plate 11 are tangent at point C.

[0116] The y-direction limiting block 14 is sleeved on the outside of the straight rod 10 to limit the straight rod 10 to move only in the y-direction.

[0117] The adjustable arc plate 11 includes an adjustable arc segment 15 which can be retracted below the adjustable arc plate 11 and whose left boundary is flush with point C.

[0118] The upper and lower positions of the straight rod 10 are determined by the profile of the curved slider 12; after the height of the straight rod 10 is increased, it drives the adjustable arc plate 11 upward, and makes the slider 5 move in the slide groove 13 along the slide groove in the negative x direction, and a gap is generated in the y direction between the third-stage telescopic shock wave inclined plate 3 and the adjustable arc plate 11. The slide groove 13 is located on the adjustable arc segment 15 of the adjustable arc plate 11, and the slider 5 is inserted in the slide groove 13 of the adjustable arc segment 15. The slider 5 slides to the left and drives the adjustable arc segment 15 to move to the left to compensate for the gap between the adjustable arc plate 11 and the third-stage telescopic shock wave inclined plate 3, thereby ensuring that BC is tangent to the adjustable arc plate 11.

[0119] When the straight rod 10 moves downward, the adjustable circular arc plate 11 also moves downward, and the adjustable circular arc segment 15 in the adjustable circular arc plate 11 slides to the right along the circular arc profile and shrinks inside the adjustable circular arc plate 11 .

[0120] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A single-degree-of-freedom steplessly adjustable TBCC inlet duct flow control method, characterized in that: The system comprises a first-stage fixed shock wave inclined plate (1), a second-stage rotating shock wave inclined plate (2), and a third-stage telescopic shock wave inclined plate (3) which are connected in sequence along the incoming flow direction. The coordinate system is established by setting: the intersection of the first-stage fixed shock wave inclined plate (1) and the forebody at the front of the air inlet as the origin, the incoming flow direction along the air inlet as the positive x direction, and the y direction being perpendicular to the incoming flow direction of the air inlet; The adjustable circular arc plate (11) is hinged at the rear of the third-stage telescopic shock wave inclined plate (3); the adjustable lip cover (4) is arranged above the adjustable circular arc plate (11); the first-stage fixed shock wave inclined plate (1), the second-stage rotating shock wave inclined plate (2), the third-stage telescopic shock wave inclined plate (3), the upper surface of the adjustable circular arc plate (11) and the lower surface of the adjustable lip cover (4) form an air inlet profile; The positions of both ends of the first-stage fixed shock wave inclined plate (1) are fixed, the position of the connection point A between the second-stage rotating shock wave inclined plate (2) and the first-stage fixed shock wave inclined plate (1) is fixed, the connection point B between the second-stage rotating shock wave inclined plate (2) and the third-stage telescopic shock wave inclined plate (3) rotates around point A, point B is movably overlapped on the upper surface of the curved slider (12), and the position of point B is determined by the profile contour line of the upper surface when the curved slider (12) moves left and right. Point C is the connection point between the adjustable circular arc plate (11) and the third-stage telescopic shock wave inclined plate (3), and BC of the third-stage telescopic shock wave inclined plate (3) is a straight line segment. It also includes a control device, which includes a curved slider (12) and a left-right adjustment mechanism for driving the curved slider (12) to move left-right; This control method is a single degree of freedom adjustment, that is, only one degree of freedom of the displacement of the left and right adjustment mechanisms is needed to simultaneously change the positions of point B and point C, thereby adjusting the outer compression profile of the inlet duct. By adjusting the positions of point B and point C, it is ensured that BC and the adjustable arc plate (11) are tangent at point C; The control device comprises a curved slider (12), a slider (5), and a straight rod (10), and the left and right adjustment mechanism is a telescopic screw rod (9); The curved slider (12) is connected to the telescopic screw rod (9) on one side along the positive x direction. A straight rod (10) is provided between the upper part of the curved slider (12) and the adjustable circular arc plate (11). The top of the straight rod (10) is hinged to the bottom of the adjustable circular arc plate (11). The bottom of the straight rod (10) is movably arranged on the curved slider (12). The slide groove (13) is located on the adjustable circular arc plate (11). The shape and curvature of the slide groove (13) are consistent with the curvature of the adjustable circular arc plate (11). The slider (5) is slidably connected in the slide groove (13). The curved slider (12) is controlled to move forward and backward by rotating the telescopic screw rod (9), thereby controlling the vertical movement of the straight rod (10) and the intersection point B of the second-stage rotating shock wave inclined plate (2) and the third-stage telescopic shock wave inclined plate (3) to move along the upper surface of the curved slider (12); The adjustable circular arc plate (11) comprises an adjustable circular arc section (15) which can be retracted below the adjustable circular arc plate (11) and whose left boundary is flush with the third-stage telescopic shock wave inclined plate (3) when retracted; The upper and lower positions of the straight rod (10) are determined by the profile of the curved slider (12); when the height of the straight rod (10) is increased, the adjustable circular arc plate (11) is driven upward, and the slider (5) is moved in the slide groove (13) along the slide groove in the negative x direction, so that a gap is generated between the third-stage telescopic shock wave inclined plate (3) and the adjustable circular arc plate (11) in the y direction; the slide groove (13) is located on the adjustable circular arc segment (15) of the adjustable circular arc plate (11); the slider (5) is inserted into the slide groove (13) of the adjustable circular arc segment (15); the slider (5) slides leftward to drive the adjustable circular arc segment (15) to move leftward to compensate for the gap between the adjustable circular arc plate (11) and the third-stage telescopic shock wave inclined plate (3), thereby ensuring that BC and the adjustable circular arc plate (11) are tangent.

2. The single-degree-of-freedom steplessly adjustable TBCC intake duct flow control method according to claim 1, characterized in that: The y-direction limiting block (14) is sleeved on the outside of the straight rod (10) and is used to limit the straight rod (10) to move only in the y-direction.

3. The single-degree-of-freedom steplessly adjustable TBCC intake duct flow control method according to claim 1, characterized in that: One end of the splitter plate (6) overlaps the adjustable arc plate (11) to close the turbine channel; or rotates around the splitter plate axis (16) to the upper wall surface to close the stamping channel.

4. The single-degree-of-freedom steplessly adjustable TBCC intake duct flow control method according to claim 1, characterized in that: The intersection point between the lower end of the straight rod (10) and the curved slider (12) is point I; the profile of the curved slider (12) is fitted by a formula.

5. The single-degree-of-freedom steplessly adjustable TBCC intake duct flow control method according to claim 1, characterized in that: The capture area A0 is obtained from the incoming flow Mach number, flight altitude and capture flow rate, and then combined with the inlet duct width-to-height ratio, the capture section width and height, i.e., the y coordinate of the lip point, are obtained; the angles of each shock wave are further determined by the optimal wave system configuration relationship of the design point, and then the length L1 of the first-stage fixed shock wave ramp (1) and the length L2 of the second-stage rotating shock wave ramp (2) are determined according to the capture section height and the shock wave angles of each stage and through geometric relationships; the inclination angle θ1 of the first-stage fixed shock wave ramp (1) is determined by the shock wave relationship, and the first-stage fixed shock wave ramp (1) and the second-stage rotating shock wave ramp (2) intersect at a fixed point A, and the coordinate expression is: ； The second-stage rotating shock wave inclined plate (2) performs a rotating motion around point A under the control of an external force, and the inclination angle θ2 varies with the incoming flow Mach number. The specific adjustment rule is determined by the designer according to the aerodynamic performance under different incoming flow Mach numbers. θ2 is the horizontal angle of the second-stage rotating shock wave inclined plate (2). The second-stage rotating shock wave inclined plate (2) intersects with the third-stage telescopic shock wave inclined plate (3) at point B. The coordinate of point B varies with the second-stage rotating shock wave inclined plate (2). The specific expression is: ； According to the geometric relationship, the inclination angle θ2 of the second-stage rotating shock wave inclined plate (2) is determined according to the length of the third-stage telescopic shock wave inclined plate (3), the radius R of the circular arc plate, and the y-coordinate H of the right end point of the circular arc plate. The relationship of θ2 is as follows: （1） Wherein, θ3 is the horizontal angle of the third-stage telescopic shock wave ramp (3); The third-stage telescopic shock wave inclined plate (3): after being subjected to external force, the length L3 and the inclination angle θ3 are adjusted by the y coordinate H of the right end point of the adjustable circular arc plate and the coordinate of point B to determine the angle and length of the third-stage telescopic shock wave inclined plate (3), θ3 being the horizontal angle of the third-stage telescopic shock wave inclined plate (3). The relationship between the length L3 and the inclination angle θ3 with the lengths L1 and L2, the inclination angles θ1 and θ2, the radius R of the adjustable circular arc plate and the y coordinate H of the right end point of the adjustable circular arc plate (11) is established by geometric relationship as follows: （2） (3) Further, θ3 is obtained according to formula (2) based on H, and the length L3 is further determined according to formula (3).

6. The single-degree-of-freedom steplessly adjustable TBCC intake duct flow control method according to claim 5, characterized in that: Under different incoming flow Mach numbers, determine the values ​​of θ1, θ2, θ3, L1, L2, L3, H, and the coordinates of points A, B, C, and I with the profile layout that best suits the working conditions; The coordinates of points B and I are determined through multiple tests, and the coordinates are interpolated to fit the forming line to determine the shape of the curved slider (12); The shape fitting process of the curved slider (12) is as follows: The coordinates of point A, point B, point I, θ1, θ2, θ3, L1, L2, L3, and H are determined by the following formula: （1.1） ； The following relationship can be obtained from the above formula: ； The coordinates of points A, B, and C can also be obtained: ; set up I The distance between the point and the x-axis is , the distance from the y-axis is l , so I The coordinates of a point can be expressed as: ; When the right curved slider moves, it will cause B point changes, so θ 2 will also change accordingly; at different Mach numbers, the lateral movement distance of the curved slider is Δx, B The coordinates of the points are ; Fit the coordinates of points B and I under different working conditions to obtain the profile, and then make a curved slider based on the profile; Wherein, L1 is the length of the first-stage fixed shock wave inclined plate (1); L2 is the length of the second-stage rotating shock wave inclined plate (2); L3 is the length of the third-stage telescopic shock wave inclined plate (3); θ1 is the angle between the first-stage fixed shock wave inclined plate (1) and the x-axis; θ2 is the horizontal angle of the second-stage rotating shock wave inclined plate (2); θ3 is the horizontal angle of the third-stage telescopic shock wave inclined plate (3); α1 is the angle between the auxiliary line perpendicular to the third-stage telescopic shock wave inclined plate (3) and the horizontal line passing through point C; α2 is the angle between the chord length K and the horizontal line passing through point C; W is the distance between point A and the y-axis; M is the distance between point A and the x-axis; E is the distance between point B and the y-axis minus W; N is the distance between point B and the x-axis minus M; P is the distance between point C and the y-axis minus W and E; Q is the distance between point C and the x-axis minus M and N; K is the chord length of the arc plate; G is the distance between the horizontal line passing through point C and the right end point of the arc plate; H is the distance between the right end point of the arc plate and the x-axis; R is the radius of the arc; Δh is the ordinate of point I, l is the horizontal coordinate of point I; Secondly, after obtaining the coordinates of points B and I, the curved slider profile is determined through Lagrange interpolation.

7. A single-degree-of-freedom steplessly adjustable TBCC inlet duct flow control device, used in any one of the control methods of claims 1 to 6, characterized in that: The device comprises a first-stage fixed shock wave inclined plate (1), a second-stage rotating shock wave inclined plate (2), and a third-stage telescopic shock wave inclined plate (3) which are connected in sequence along the incoming flow direction. The coordinate system is established by setting: the intersection of the first-stage fixed shock wave inclined plate (1) and the forebody at the front of the air inlet as the origin, the direction from the first-stage fixed shock wave inclined plate (1) to the second-stage rotating shock wave inclined plate (2) in the air inlet as the positive x direction, and the normal direction away from the air inlet as the y axis; The adjustable circular arc plate (11) is hinged at the rear of the third-stage telescopic shock wave inclined plate (3); the adjustable lip cover (4) is arranged above the adjustable circular arc plate (11); the first-stage fixed shock wave inclined plate (1), the second-stage rotating shock wave inclined plate (2), the third-stage telescopic shock wave inclined plate (3), the adjustable circular arc plate (11), and the adjustable lip cover (4) together form an entire air inlet flow channel; The positions of both ends of the first-stage fixed shock wave inclined plate (1) are fixed, the position of the connection point A between the second-stage rotating shock wave inclined plate (2) and the first-stage fixed shock wave inclined plate (1) is fixed, the connection point B between the second-stage rotating shock wave inclined plate (2) and the third-stage telescopic shock wave inclined plate (3) rotates around point A, point B is movably overlapped on the upper surface of the curved slider (12), and the position of point B is determined by the profile contour line of the upper surface when the curved slider (12) moves left and right. Point C is the connection point between the adjustable circular arc plate (11) and the third-stage telescopic shock wave inclined plate (3), and BC of the third-stage telescopic shock wave inclined plate (3) is a straight line segment. The invention also comprises a control device; the control device comprises a curved slider (12), a slider (5), a straight rod (10), and a telescopic screw rod (9) for driving the curved slider (12) to move left and right; the curved slider (12) is connected to the telescopic screw rod (9) on one side along the positive x direction; a straight rod (10) is provided between the upper part of the curved slider (12) and the adjustable circular arc plate (11); the top of the straight rod (10) is hinged to the bottom of the adjustable circular arc plate (11); the bottom of the straight rod (10) is movably arranged on the curved slider (12); the adjustable circular arc plate (11) comprises an adjustable circular arc segment (15) which can be retracted below the adjustable circular arc plate (11) and whose left boundary is flush with point C; the slide groove (13) is located on the adjustable circular arc segment (15) of the adjustable circular arc plate (11); the slider (5) is inserted into the slide groove (13) of the adjustable circular arc segment (15); The shape and curvature of the slide groove (13) are consistent with the curvature of the adjustable arc plate (11); the slider (5) is slidably connected in the slide groove (13); The control device is a single-degree-of-freedom adjustment device, that is, only one degree of freedom of displacement of the telescopic screw (9) needs to be controlled to simultaneously change the positions of point B and point C, thereby adjusting the external compression profile of the air inlet duct. By adjusting the positions of point B and point C, it is ensured that BC and the adjustable arc plate (11) are tangent at point C.

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