Design method and system, device and medium for a sideward bending tail nozzle of a turboshaft engine

Abstract

The application discloses a design method and system, equipment and medium of a side bending tail nozzle of a turboshaft engine, which adopts parameterized design, determines initial geometric design parameters of the side bending tail nozzle first, then constructs an outflow channel profile based on the initial geometric design parameters, designs a profile of a nozzle cross section based on an area change curve of the nozzle cross section, and generates an overall aerodynamic profile based on the initial design parameters, the outflow channel profile and the profile of the nozzle cross section, so that the aerodynamic profile of the side bending tail nozzle can be quickly designed, the profile design is controllable, the unique determination of the transition profile of the tail nozzle is realized, the design efficiency and universality of the side bending tail nozzle are enhanced, and the design period can be significantly reduced.

Description

Technical Field

[0001] This invention relates to the field of aero-engine exhaust nozzle design technology, and in particular, to a design method and system for a lateral bending exhaust nozzle of a turboshaft engine, electronic equipment, and a computer-readable storage medium. Background Technology

[0002] The exhaust nozzle is used to expel the exhaust gas flow and also acts as a decelerator and diffuser. Generally, turbojet engines use convergent nozzles, while turboshaft engines use simple subsonic diffusers. This allows the gas to fully expand and do work within the free turbine, resulting in a static pressure at the turbine outlet lower than atmospheric pressure. Diffusion is necessary before the gas can be expelled into the atmosphere, aiming to maximize the conversion of enthalpy from the free turbine into shaft power. Depending on the turboshaft engine's output method, the exhaust system design varies significantly. Front-output-shaft turboshaft engines have a simpler exhaust system design, primarily an axisymmetric diffuser cylindrical shape. Rear-output-shaft turboshaft engines, however, require the power turbine output shaft to pass through the nozzle, necessitating a laterally curved nozzle, which presents significant structural design challenges. Currently, the design of laterally curved nozzles relies on engineers adjusting the shape of several spline curves based on engineering experience. This process is uncontrollable, resulting in unpredictable nozzle profile parameters, making profile adjustment difficult, hindering efficient design and optimization, and proving time-consuming and labor-intensive, ultimately failing to meet the design requirements of laterally curved nozzles. Summary of the Invention

[0003] This invention provides a design method and system for a laterally curved exhaust nozzle of a turboshaft engine, as well as electronic equipment and a computer-readable storage medium, to solve the technical problems of uncontrollable surface design and difficulty in achieving efficient design and optimization in existing laterally curved exhaust nozzle structural design methods.

[0004] According to one aspect of the present invention, a design method for a laterally curved exhaust nozzle of a turboshaft engine is provided, comprising the following:

[0005] Determine the initial design parameters for the lateral bending tail nozzle;

[0006] The outer flow channel profile of the laterally curved tail nozzle was designed based on the initial design parameters;

[0007] Select the area variation curve of the nozzle friction section and design the profile of the nozzle friction section.

[0008] The aerodynamic profile of the laterally curved tail nozzle is generated based on the initial design parameters, the outer flow channel profile, and the profile of the nozzle friction section.

[0009] Furthermore, the initial design parameters include the nozzle inlet outer channel diameter, nozzle inlet inner channel diameter, nozzle diffuser section length, nozzle diffuser section outer channel angle, nozzle diffuser section inner channel angle, center cone angle, axial distance from the root of the support plate to the nozzle inlet, axial distance from the nozzle inlet to the outlet centerline, height of the nozzle inlet centerline from the outlet section, nozzle bend angle, and nozzle outlet area.

[0010] Furthermore, the process of designing the outer flow channel profile of the laterally curved nozzle based on the initial design parameters includes the following:

[0011] The outer flow profile of the annular diffuser section is determined based on the nozzle inlet outer flow channel diameter, nozzle diffuser section length, and nozzle diffuser section outer flow channel angle. A total of four outer flow channel profiles for the annular diffuser section are designed: upper, left, lower, and right.

[0012] The inlet section of the curved section is used as the first reference plane, and the starting coordinates of the upper, left, lower and right outer flow channel profiles of the curved section are determined in combination with the diameter of the nozzle inlet outer flow channel.

[0013] The position of the nozzle exit section is determined based on the axial distance from the nozzle inlet to the exit centerline and the height of the nozzle inlet centerline from the exit section. The nozzle exit section is used as the second reference plane, and the end coordinates of the upper, left, lower, and right outer flow channel profiles of the curved section are solved based on the shape of the nozzle exit section.

[0014] Based on the starting and ending coordinates of the four outer flow channel profiles (upper, left, lower, and right) of the curved section, as well as the outer flow channel angle of the nozzle diffuser section and the bending angle of the nozzle curved section, the four outer flow channel profiles of the curved section are designed using the F-value curve.

[0015] Furthermore, when the nozzle exit cross-section is a rounded rectangle, the semi-width of the major axis and the semi-width of the minor axis are calculated based on the following formula:

[0016]

[0017]

[0018] When the nozzle exit cross-section is elliptical, the semi-width of the major axis and the semi-width of the minor axis are calculated based on the following formula:

[0019]

[0020]

[0021] Where w2 and h2 represent the semi-width of the major axis and the semi-width of the minor axis, respectively, AR represents the aspect ratio of the nozzle exit section, and r e Let A represent the radius of the vertex arc of the rounded rectangle. uThe nozzle exit area is represented by the coordinates of the endpoints of the four outer flow channel profiles (upper, left, lower, and right) of the curved section, which are O1(x). o1 ,y o1 O2(x) o2 ,y o2 O3(x) o3 ,y o3 O4(x) o4 ,y o4 ), x o2 x o4 y o1 y o3 All are 0, x o1 For h2, x o3 For -h2, y o2 For -w2, y o4 It is w2.

[0022] Furthermore, the area change curve of the nozzle's cross-section along the nozzle path can be any one of the following: a curve with a sharp initial movement followed by a gradual decline, a curve with a gradual initial movement followed by a sharp decline, or a curve with a relatively even variation in speed. The expression for the curve with a sharp initial movement followed by a gradual decline is:

[0023]

[0024] The expression for a curve that is gentle at the beginning and steep at the end is:

[0025]

[0026] The expression for the equal curve of steepness and slowness is:

[0027]

[0028] Where A represents the cross-sectional area of ​​the nozzle along the friction section, x represents the axial distance from the centerline of the nozzle along the friction section to the nozzle inlet, and L represents the axial distance from the inlet of the lower guide line of the laterally bent tail nozzle to the outlet center. in A represents the inlet area of ​​the nozzle outer flow channel. out This represents the area of ​​the cross-section perpendicular to the lower profile at the end point of the curved section.

[0029] Furthermore, the process of designing the profile of the nozzle's friction section includes the following:

[0030] The profile of the nozzle friction section is constructed using a hyperelliptic curve. The major and minor axes of the hyperelliptic curve are determined based on the intersection of the nozzle friction section with the profiles of the four outer flow channels (upper, left, lower, and right) of the curved section. The profiles of several hyperelliptic sections are determined by combining the cross-sectional area of ​​the nozzle friction section with the formula for the hyperelliptic area.

[0031] Furthermore, the process of generating the aerodynamic profile of the laterally curved tail nozzle based on the initial design parameters, the outer flow channel profile, and the profile of the nozzle friction section includes the following:

[0032] The profile of the diffuser section is generated based on the nozzle inlet outer channel diameter, nozzle diffuser section length, nozzle diffuser section outer channel angle, nozzle inlet inner channel diameter, and nozzle diffuser section inner channel angle.

[0033] The outer flow channel profile of the curved section is generated based on the outer flow channel profile of the curved section and the profile of the nozzle friction section.

[0034] The profile of the central cone is generated based on the angle of the central cone and the profile of the inner flow channel of the diffuser section;

[0035] Select the type and quantity of the rectifier support plate, and generate the profile of the rectifier support plate according to the axial distance from the root of the leading edge of the support plate to the nozzle inlet;

[0036] The aerodynamic profile of the laterally curved nozzle is generated by combining the profiles of the diffuser section, the outer flow channel of the curved section, the central cone, and the straightening support plate.

[0037] In addition, the present invention also provides a design system for a laterally curved exhaust nozzle of a turboshaft engine, employing the design method described above, including:

[0038] The initial design parameter setting module is used to determine the initial design parameters of the lateral bending nozzle;

[0039] The outer flow channel profile design module is used to design the outer flow channel profile of the laterally curved tail nozzle based on the initial design parameters;

[0040] The nozzle friction profile design module is used to select the area variation curve of the nozzle friction profile and design the profile of the nozzle friction profile.

[0041] The aerodynamic profile generation module is used to generate the aerodynamic profile of the laterally curved tail nozzle based on the initial design parameters, the outer flow channel profile, and the profile of the nozzle's friction section.

[0042] In addition, the present invention also provides an electronic device, including a processor and a memory, wherein the memory stores a computer program, and the processor executes the steps of the method described above by calling the computer program stored in the memory.

[0043] In addition, the present invention provides a computer-readable storage medium for storing a computer program for designing a lateral bending exhaust nozzle for a turboshaft engine, wherein the computer program, when run on a computer, performs the steps of the method described above.

[0044] The present invention has the following effects:

[0045] The design method for the laterally curved nozzle of a turboshaft engine of the present invention adopts parametric design. First, the initial geometric design parameters of the laterally curved nozzle are determined. Then, the outer flow channel profile is constructed based on the initial geometric design parameters. The profile of the nozzle's friction section is designed based on the area change curve of the nozzle's friction section. Finally, the overall aerodynamic profile is generated based on the initial design parameters, the outer flow channel profile, and the profile of the nozzle's friction section. This method can quickly design the aerodynamic profile of the laterally curved nozzle, achieves controllable profile design, and enables the unique determination of the transition profile of the nozzle along the friction path. This enhances the design efficiency and versatility of the laterally curved nozzle and can significantly reduce the design cycle.

[0046] In addition, the design system for the lateral bending exhaust nozzle of the turboshaft engine of the present invention also has the above-mentioned advantages.

[0047] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0048] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0049] Figure 1 This is a schematic diagram of the laterally curved exhaust nozzle of a turboshaft engine with power turbine output.

[0050] Figure 2 This is a flowchart illustrating the design method of a lateral bending tail nozzle for a turboshaft engine according to a preferred embodiment of the present invention.

[0051] Figure 3 yes Figure 2 A schematic diagram of the sub-process of step S2.

[0052] Figure 4 This is a schematic diagram of the design of the F-value curve in a preferred embodiment of the present invention.

[0053] Figure 5 This is a schematic diagram of the inlet cross-section of the curved section in a preferred embodiment of the present invention.

[0054] Figure 6 This is a schematic diagram of the rounded rectangular outlet section of a preferred embodiment of the present invention.

[0055] Figure 7 This is a schematic diagram of the elliptical exit cross-section of a preferred embodiment of the present invention.

[0056] Figure 8 yes Figure 2 A schematic diagram of the sub-process of step S4.

[0057] Figure 9 This is a schematic diagram of the outer flow channel profile of the laterally curved tailpipe designed in a preferred embodiment of the present invention.

[0058] Figure 10 This is a schematic diagram of the aerodynamic profile of a laterally curved tailpipe designed according to a preferred embodiment of the present invention.

[0059] Figure 11 This is a flowchart illustrating the design system for a lateral bending exhaust nozzle of a turboshaft engine, according to another embodiment of the present invention. Detailed Implementation

[0060] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0061] Understandable, such as Figure 1 As shown, in this invention, the lateral curved nozzle of the power turbine rear-output turboshaft engine includes an annular diffuser section, a curved section, a central cone, and a straightening support plate. The inlet of the annular diffuser section connects to the outlet of the engine turbine casing, and the outlet of the annular diffuser section connects to the curved section and the central cone. The cross-sectional shape of the curved section transitions from an annular shape at the inlet to a rounded rectangle or ellipse at the outlet. The rear output shaft passes through the central cone. The curved section has a hole for connection to the central cone, and the central cone has a transition arc for connection to the curved section. The outer edge sectional line of the transition arc on the central cone is the same as the profile of the pre-drilled hole on the curved section, thus achieving the connection between the central cone and the curved section. The straightening support plate has a transition arc, and the central cone and the curved section have pre-drilled holes at corresponding positions, enabling the internal connection of the straightening support plate to the central cone and the external connection to the curved section. The central cone and the curved section, and the straightening support plate and the central cone and the curved section are assembled using a welding process. The airflow process in the tail nozzle is as follows: the airflow enters through the annular inlet formed by the central cone and the curved section of the nozzle, passes through the straightening support plate, turns along the curved channel of the curved section, bypasses the central cone in the middle, and flows towards the outlet along the flow channel profile of the curved section.

[0062] Understandable, such as Figure 2 As shown, a preferred embodiment of the present invention provides a design method for a laterally curved exhaust nozzle of a turboshaft engine, comprising the following:

[0063] Step S1: Determine the initial design parameters for the lateral bending nozzle;

[0064] Step S2: Design the outer flow channel profile of the laterally curved tail nozzle based on the initial design parameters;

[0065] Step S3: Select the area variation curve of the nozzle friction section and design the profile of the nozzle friction section;

[0066] Step S4: Generate the aerodynamic profile of the laterally curved tail nozzle based on the initial design parameters, the outer flow channel profile, and the profile of the nozzle's friction section.

[0067] It is understood that the design method of the turboshaft engine lateral bending nozzle in this embodiment adopts parametric design. First, the initial geometric design parameters of the lateral bending nozzle are determined. Then, the outer flow channel profile is constructed based on the initial geometric design parameters. The profile of the nozzle's friction section is designed based on the area change curve of the nozzle's friction section. Finally, the overall aerodynamic profile is generated based on the initial design parameters, the outer flow channel profile, and the profile of the nozzle's friction section. This allows for the rapid design of the aerodynamic profile of the lateral bending nozzle, achieving controllable profile design and unique determination of the nozzle's friction transition profile. This enhances the design efficiency and versatility of the lateral bending nozzle and significantly reduces the design cycle.

[0068] It is understood that in step S1, as Figure 1 As shown, the initial design parameters include the nozzle inlet outer flow channel diameter. nozzle inlet inner flow channel diameter nozzle diffuser section length L d The outer flow channel angle α of the nozzle diffuser section w The internal flow channel angle α of the nozzle diffuser section n The angle α of the central cone c The axial distance L from the root of the support plate to the nozzle inlet s axial distance L from nozzle inlet to outlet centerline t The height H of the nozzle inlet centerline from the outlet section t The bending angle β of the nozzle's curved section and the nozzle exit area A u .

[0069] Understandable, such as Figure 3 As shown, in step S2, the process of designing the outer flow channel profile of the laterally curved nozzle based on the initial design parameters includes the following:

[0070] Step S21: Determine the outer flow profile of the annular diffuser section based on the nozzle inlet outer flow channel diameter, nozzle diffuser section length, and nozzle diffuser section outer flow channel angle. A total of four outer flow channel profiles for the annular diffuser section are designed: upper, left, lower, and right.

[0071] Step S22: Using the inlet section of the curved section as the first reference plane, and in conjunction with the diameter of the nozzle inlet outer flow channel, determine the starting coordinates of the four outer flow channel profiles of the upper, left, lower, and right sides of the curved section;

[0072] Step S23: Determine the position of the nozzle exit section based on the axial distance between the nozzle inlet and the exit centerline and the height of the nozzle inlet centerline from the exit section. Use the nozzle exit section as the second reference plane and solve for the endpoint coordinates of the upper, left, lower, and right outer flow channel profiles of the curved section based on the shape of the nozzle exit section.

[0073] Step S24: Based on the starting and ending coordinates of the four outer flow channel profiles of the upper, left, lower and right sections of the curved section, as well as the outer flow channel angle of the nozzle diffuser section and the bending angle of the nozzle curved section, the four outer flow channel profiles of the curved section are designed using the F-value curve.

[0074] Specifically, the outer flow channel profile of the laterally curved nozzle includes the outer flow channel profile of the annular diffuser section and the outer flow channel profile of the curved section. The outer flow channel profile of the annular diffuser section can be based on the nozzle inlet outer flow channel diameter. nozzle diffuser section length L d α, the angle of the outer flow channel of the nozzle diffuser section w It has been determined that four external flow channel profiles—upper, left, lower, and right—are designed for the annular diffuser section.

[0075] The outer flow channel profile of the curved section is designed using a parameter-controllable F-value curve, the expression of which is: ax 2 +bx+cxy+dy 2 +ey+f=0, where a, b, c, d, e, and f represent curve parameters. For example... Figure 4 As shown, the F-value of the F-value curve is defined as the ratio of the length of line segment DE to the length of line segment CD, i.e., F = |DE| / |CD|. The curve can be obtained by determining the coordinates of the two endpoints of the F-value curve and the angle between the tangent line at the two endpoints and the x-axis, and combining the F-value.

[0076] like Figure 5 As shown, taking the inlet section of the curved section as the first reference plane, that is, taking the center of the inlet section as the origin, the vertical direction as the Z-axis, and the horizontal direction as the Y-axis, the first reference plane OYZ is constructed. Then, the starting coordinates of the four outer flow channel profiles of the curved section (upper, left, lower, and right) are I1(y... i1 ,z i1 ), I2(y i2 ,z i2 ), I3(y i3 ,z i3 ), I4(y i4 ,z i4 ), where y i1 y i3 z i2 z i4 Both are 0, y i4 and z i1 for y i2 and z i3 for

[0077] Then, based on the axial distance L from the nozzle inlet to the outlet centerline t The height H of the nozzle inlet centerline from the outlet section t Determine the location of the nozzle exit section, and use the nozzle exit section as the second reference plane, such as... Figure 6 and Figure 7 As shown, a second reference plane OYX is constructed with the center of the nozzle exit section as the origin, the vertical direction as the X-axis, and the horizontal direction as the Y-axis. The endpoint coordinates of the four outer flow channel profiles (upper, left, lower, and right) of the curved section are then calculated based on the shape of the nozzle exit section. When the nozzle exit section is a rounded rectangle, the semi-width of the major axis and the semi-width of the minor axis are calculated using the following formula:

[0078]

[0079]

[0080] When the nozzle exit cross-section is elliptical, the semi-width of the major axis and the semi-width of the minor axis are calculated based on the following formula:

[0081]

[0082]

[0083] Where w2 and h2 represent the semi-width of the major axis and the semi-width of the minor axis, respectively, AR represents the aspect ratio of the nozzle exit section, and r e Let A represent the radius of the vertex arc of the rounded rectangle. u This represents the nozzle exit area. Given the nozzle exit area A... u Given the aspect ratio (major axis / minor axis) AR of the nozzle exit section and the radius r of the apex arc. e Then, the semi-width of the major axis and the semi-width of the minor axis of the rounded rectangular exit section can be calculated; given the nozzle exit area A... u Given the aspect ratio (major axis / minor axis) AR of the nozzle exit section, the semi-widths of the major and minor axes of the elliptical exit section can be calculated. Then, the endpoint coordinates of the four outer flow channel profiles (upper, left, lower, and right) of the curved section are O1(x... o1 ,y o1 O2(x) o2 ,y o2 O3(x) o3 ,y o3 O4(x) o4 ,y o4 ), x o2 xo4 y o1 y o3 All are 0, x o1 For h2, x o3 For -h2, y o2 For -w2, y o4 It is w2.

[0084] Based on the above process, the starting and ending coordinates of each outer channel profile can be determined, and the included angle at the starting end is the outer channel angle α of the nozzle diffuser section. w The included angle at the end point is the bending angle β of the nozzle bending section. After giving the F value, the F value curve can be calculated, thereby designing the upper, left, lower and right outer flow channel profiles of the bending section.

[0085] It is understood that in step S3, the area change curve of the nozzle's cross-section along the nozzle can be any one of the following: a curve with a sharp initial movement followed by a gradual change, a curve with a gradual initial movement followed by a sharp change, or a curve with a relatively even variation in speed. The expression for the curve with a sharp initial movement followed by a gradual change is:

[0086]

[0087] The expression for a curve that is gentle at the beginning and steep at the end is:

[0088]

[0089] The expression for the equal curve of steepness and slowness is:

[0090]

[0091] Where A represents the cross-sectional area of ​​the nozzle along the friction section, x represents the axial distance from the centerline of the nozzle along the friction section to the nozzle inlet, and L represents the axial distance from the inlet of the lower guide line of the laterally bent tail nozzle to the outlet center. in Indicates the inlet area of ​​the nozzle's outer flow channel. A out A represents the area of ​​the cross-section perpendicular to the lower profile at the endpoint of the curved section. out =A u sinβ. Therefore, after selecting the area change curve of the nozzle friction section, A can be calculated. in and A out This allows us to calculate the cross-sectional area of ​​several nozzle sections along their travel path.

[0092] It can be understood that, in step S3, the process of designing the profile of the nozzle's friction section includes the following:

[0093] The profile of the nozzle friction section is constructed using a hyperelliptic curve. The major and minor axes of the hyperelliptic curve are determined based on the intersection of the nozzle friction section with the profiles of the four outer flow channels (upper, left, lower, and right) of the curved section. The profiles of several hyperelliptic sections are determined by combining the cross-sectional area of ​​the nozzle friction section with the formula for the hyperelliptic area.

[0094] Specifically, the nozzle friction profile is constructed using a hyperelliptic curve, where the expression for a standard hyperellipse is: Based on this formula, the formula for the area of ​​the hyperellipse can be derived as follows: Based on the above process, the cross-sectional area A of several nozzle friction sections can be obtained. Then, the major semi-axis a and minor semi-axis b of the hyperellipse can be determined according to the intersection of the nozzle friction section and the four outer flow channel profiles on the upper, left, lower and right sides of the curved section. After knowing A, a and b, the exponent n of any section can be obtained according to the hyperellipse area formula, so that the profile of several hyperellipse sections can be determined.

[0095] Understandable, such as Figure 8 As shown, in step S4, the process of generating the aerodynamic profile of the laterally curved tail nozzle based on the initial design parameters, the outer flow channel profile, and the profile of the nozzle friction section includes the following:

[0096] Step S41: Generate the profile of the diffuser section based on the nozzle inlet outer channel diameter, nozzle diffuser section length, nozzle diffuser section outer channel angle, nozzle inlet inner channel diameter, and nozzle diffuser section inner channel angle.

[0097] Step S42: Generate the outer flow channel profile of the curved section based on the outer flow channel profile of the curved section and the profile of the nozzle friction section;

[0098] Step S43: Generate the profile of the central cone based on the angle of the central cone and the inner flow channel profile of the diffuser section;

[0099] Step S44: Select the type and quantity of the rectifier support plate, and generate the profile of the rectifier support plate according to the axial distance from the root of the leading edge of the support plate to the nozzle inlet;

[0100] Step S45: Combine the diffuser profile, the outer flow channel profile of the curved section, the central cone profile, and the straightening support plate profile to generate the aerodynamic profile of the lateral curved tail nozzle.

[0101] Specifically, based on the nozzle inlet outer flow channel diameter nozzle diffuser section length L d α, the angle of the outer flow channel of the nozzle diffuser section w The outer flow channel profile of the annular diffuser section can be determined, while the inner flow channel diameter at the nozzle inlet can be used as a basis. nozzle diffuser section length L d The internal flow channel angle α of the nozzle diffuser sectionn This allows us to determine the inner flow channel profile of the annular diffuser section. Based on the outer and inner flow channel profiles of the annular diffuser section, the inner and outer flow channel surfaces of the annular diffuser section can be designed. Then, based on the outer flow channel profile of the curved section and the profiles of several nozzle friction sections, the outer flow channel surface of the curved section can be generated. The outer flow channel surface of the laterally curved tail nozzle is shown below. Figure 9 As shown. Then, based on the angle α of the central cone... c By combining the internal flow channel profile of the diffuser section, the profile of the central cone can be generated. The type and number of rectifying support plates can be selected; the support plate type can be straight, inclined, or curved, etc. Then, based on the axial distance L from the root of the support plate's leading edge to the nozzle inlet... s The profile of the straightener is generated. Finally, by combining the profiles of the annular diffuser section, the outer flow channel of the curved section, the central cone, and the straightener, the aerodynamic profile of the laterally curved nozzle can be generated, such as... Figure 10 As shown.

[0102] In addition, such as Figure 11 As shown, another embodiment of the present invention also provides a design system for a laterally curved exhaust nozzle of a turboshaft engine, preferably employing the design method described above, including:

[0103] The initial design parameter setting module is used to determine the initial design parameters of the lateral bending nozzle;

[0104] The outer flow channel profile design module is used to design the outer flow channel profile of the laterally curved tail nozzle based on the initial design parameters;

[0105] The nozzle friction profile design module is used to select the area variation curve of the nozzle friction profile and design the profile of the nozzle friction profile.

[0106] The aerodynamic profile generation module is used to generate the aerodynamic profile of the laterally curved tail nozzle based on the initial design parameters, the outer flow channel profile, and the profile of the nozzle's friction section.

[0107] It is understood that the design method of the turboshaft engine lateral bending nozzle in this embodiment adopts parametric design. First, the initial geometric design parameters of the lateral bending nozzle are determined. Then, the outer flow channel profile is constructed based on the initial geometric design parameters. The profile of the nozzle's friction section is designed based on the area change curve of the nozzle's friction section. Finally, the overall aerodynamic profile is generated based on the initial design parameters, the outer flow channel profile, and the profile of the nozzle's friction section. This allows for the rapid design of the aerodynamic profile of the lateral bending nozzle, achieving controllable profile design and unique determination of the nozzle's friction transition profile. This enhances the design efficiency and versatility of the lateral bending nozzle and significantly reduces the design cycle.

[0108] In addition, another embodiment of the present invention provides an electronic device including a processor and a memory, wherein the memory stores a computer program, and the processor executes the steps of the method described above by calling the computer program stored in the memory.

[0109] In addition, another embodiment of the present invention provides a computer-readable storage medium for storing a computer program for designing a lateral bending exhaust nozzle for a turboshaft engine, the computer program executing the steps of the method described above when run on a computer.

[0110] Common computer-readable storage media include: floppy disks, flexible disks, hard disks, magnetic tapes, any other magnetic media, CD-ROMs, any other optical media, punch cards, paper tape, any other physical media with perforated patterns, random access memory (RAM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), flash erasable programmable read-only memory (FLASH-EPROM), any other memory chips or cartridges, or any other media readable by a computer. Instructions may further be transmitted or received by a transmission medium. The term transmission medium can include any tangible or intangible medium used to store, encode, or carry instructions for machine execution, and includes digital or analog communication signals or intangible media that facilitate communication of such instructions. Transmission media include coaxial cables, copper wires, and optical fibers, which contain conductors for transmitting a bus of computer data signals.

[0111] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0112] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of this application can be implemented in various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0113] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0114] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0115] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0116] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0117] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A design method for a laterally curved tail nozzle of a turboshaft engine, characterized in that, Includes the following: Determine the initial design parameters for the lateral bending tail nozzle; The outer flow channel profile of the laterally curved tail nozzle was designed based on the initial design parameters; Select the area variation curve of the nozzle friction section and design the profile of the nozzle friction section. The aerodynamic profile of the laterally curved tail nozzle is generated based on the initial design parameters, the outer flow channel profile, and the profile of the nozzle friction section. The process of designing the outer flow channel profile of the laterally curved tailpipe based on initial design parameters includes the following: The outer flow profile of the annular diffuser section is determined based on the nozzle inlet outer flow channel diameter, nozzle diffuser section length, and nozzle diffuser section outer flow channel angle. A total of four outer flow channel profiles for the annular diffuser section are designed: upper, left, lower, and right. The inlet section of the curved section is used as the first reference plane, and the starting coordinates of the upper, left, lower and right outer flow channel profiles of the curved section are determined in combination with the diameter of the nozzle inlet outer flow channel. The position of the nozzle exit section is determined based on the axial distance from the nozzle inlet to the exit centerline and the height of the nozzle inlet centerline from the exit section. The nozzle exit section is used as the second reference plane, and the end coordinates of the upper, left, lower, and right outer flow channel profiles of the curved section are solved based on the shape of the nozzle exit section. Based on the starting and ending coordinates of the four outer flow channel profiles (upper, left, lower, and right) of the curved section, as well as the outer flow channel angle of the nozzle diffuser section and the bending angle of the nozzle curved section, the four outer flow channel profiles of the curved section are designed using the F-value curve. The process of designing the profile of the nozzle's friction section includes the following: The profile of the nozzle friction section is constructed using a hyperelliptic curve. The major and minor axes of the hyperelliptic curve are determined based on the intersection of the nozzle friction section with the profiles of the four outer flow channels (upper, left, lower, and right) of the curved section. The profiles of several hyperelliptic sections are determined by combining the cross-sectional area of ​​the nozzle friction section with the formula for the hyperelliptic area.

2. The design method for the lateral bending tail nozzle of a turboshaft engine as described in claim 1, characterized in that, The initial design parameters include the nozzle inlet outer channel diameter, nozzle inlet inner channel diameter, nozzle diffuser section length, nozzle diffuser section outer channel angle, nozzle diffuser section inner channel angle, center cone angle, axial distance from the root of the support plate to the nozzle inlet, axial distance from the nozzle inlet to the outlet centerline, height of the nozzle inlet centerline from the outlet section, nozzle bend angle, and nozzle outlet area.

3. The design method for the lateral bending exhaust nozzle of a turboshaft engine as described in claim 1, characterized in that, When the nozzle exit section is a rounded rectangle, the semi-width of the major axis and the semi-width of the minor axis are calculated based on the following formula: ； ； When the nozzle exit cross-section is elliptical, the semi-width of the major axis and the semi-width of the minor axis are calculated based on the following formula: ； ； Where w2 and h2 represent the semi-width of the major axis and the semi-width of the minor axis, respectively, AR represents the aspect ratio of the nozzle exit section, and r e Let A represent the radius of the vertex arc of the rounded rectangle. u The nozzle exit area is represented by the coordinates of the endpoints of the four outer flow channel profiles (upper, left, lower, and right) of the curved section, which are O1 (x...). o1 ,y o1 O2 (x) o2 ,y o2 O3 (x) o3 ,y o3 O4 (x) o4 ,y o4 ), x o2 x o4 y o1 y o3 All are 0, x o1 For h2, x o3 For -h2, y o2 For -w2, y o4 It is w2.

4. The design method for the lateral bending tail nozzle of a turboshaft engine as described in claim 1, characterized in that, The area change curve of the nozzle friction section can be any one of the following: a rapid initial curve followed by a gradual final curve, a gradual initial curve followed by a rapid final curve, or a curve with equal rapid and gradual changes. The expression for the rapid initial curve followed by a gradual final curve is: ； The expression for a curve that is gentle at the beginning and steep at the end is: ； The expression for the equal curve of steepness and slowness is: ； Where A represents the cross-sectional area of ​​the nozzle along the friction section, x represents the axial distance from the centerline of the nozzle along the friction section to the nozzle inlet, and L represents the axial distance from the inlet of the lower guide line of the laterally bent tail nozzle to the outlet center. in A represents the inlet area of ​​the nozzle outer flow channel. out This represents the area of ​​the cross-section perpendicular to the lower profile at the end point of the curved section.

5. The design method for the lateral bending tail nozzle of a turboshaft engine as described in claim 1, characterized in that, The process of generating the aerodynamic profile of the laterally curved tail nozzle based on the initial design parameters, the outer flow channel profile, and the profile of the nozzle friction section includes the following: The profile of the diffuser section is generated based on the nozzle inlet outer channel diameter, nozzle diffuser section length, nozzle diffuser section outer channel angle, nozzle inlet inner channel diameter, and nozzle diffuser section inner channel angle. The outer flow channel profile of the curved section is generated based on the outer flow channel profile of the curved section and the profile of the nozzle friction section. The profile of the central cone is generated based on the angle of the central cone and the profile of the inner flow channel of the diffuser section; Select the type and quantity of the rectifier support plate, and generate the profile of the rectifier support plate according to the axial distance from the root of the leading edge of the support plate to the nozzle inlet; The aerodynamic profile of the laterally curved nozzle is generated by combining the profiles of the diffuser section, the outer flow channel of the curved section, the central cone, and the straightening support plate.

6. A design system for a laterally curved exhaust nozzle of a turboshaft engine, employing the design method described in any one of claims 1 to 5, characterized in that, include: The initial design parameter setting module is used to determine the initial design parameters of the lateral bending nozzle; The outer flow channel profile design module is used to design the outer flow channel profile of the laterally curved tail nozzle based on the initial design parameters; The nozzle friction profile design module is used to select the area variation curve of the nozzle friction profile and design the profile of the nozzle friction profile. The aerodynamic profile generation module is used to generate the aerodynamic profile of the laterally curved tail nozzle based on the initial design parameters, the outer flow channel profile, and the profile of the nozzle's friction section.

7. An electronic device, characterized in that, The method includes a processor and a memory, wherein the memory stores a computer program, and the processor executes the steps of the method as described in any one of claims 1 to 5 by calling the computer program stored in the memory.

8. A computer-readable storage medium for storing a computer program for designing a lateral bending exhaust nozzle for a turboshaft engine, characterized in that, The computer program, when run on a computer, performs the steps of the method as described in any one of claims 1 to 5.

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