Aircraft wing rib strut section parameter design method

Abstract

This application belongs to the technical field of aircraft wing rib strut cross-sectional parameter design, specifically relating to a method for designing aircraft wing rib strut cross-sectional parameters, including: determining the thickness δ of the bottom edge of the wing rib strut based on the thickness δ of the wing rib web. u ; Calculate the minimum moment of inertia I of the ribbed strut. umin ; Calculate the minimum area A of the ribbed strut cross section. umin ; Calculate the top pressure load R of the ribbed strut. 0 ; Calculate the thermal stress load R of the rib support. t ; Calculate the working stress σ of the ribbed strut section; Calculate the critical instability stress σ of the ribbed strut section cr ; Calculate the safety margin MS of the ribbed strut; The minimum moment of inertia I of the ribbed strut umin Minimum area A of the cross-section of the ribbed strut umin Under the constraint that the safety margin MS of the ribbed strut is greater than 0, find the area A of the ribbed strut cross section. u The minimum width b of the bottom edge of the wing-rib support 2 The height b of the web of the wing-rib support 1 The thickness t of the web of the wing-rib support 1 .

Description

A method for designing cross-sectional parameters of aircraft wing rib struts Technical Field

[0001] This application belongs to the technical field of aircraft wing rib strut cross-sectional parameter design, specifically relating to a method for designing aircraft wing rib strut cross-sectional parameters. Background Technology

[0002] Composite materials are widely used for the skin and stringers of aircraft wings, while the wing ribs are made of metal. During the service of an aircraft, temperature changes will occur. Due to the large difference in the coefficients of thermal expansion between composite materials and metals, large thermal stress will be generated on the wing ribs, which may cause buckling instability of the wing rib struts. In order to avoid this situation, the current design of the cross-sectional parameters of the wing rib struts is relatively conservative, resulting in a large mass, which is inconsistent with the current requirements for aircraft weight reduction. Therefore, this application is made.

[0003] It should be noted that the above background information is only used to assist in understanding the inventive concept and technical solution of this invention, and it does not necessarily belong to the prior art of this patent application. In the absence of clear evidence that the above information was disclosed on the filing date of this application, the above background information should not be used to evaluate the novelty and inventiveness of this application. Summary of the Invention

[0004] The purpose of this application is to provide a method for designing the cross-sectional parameters of aircraft wing rib struts, so as to overcome or mitigate at least one of the known technical defects.

[0005] The technical solution of this application is:

[0006] A method for designing the cross-sectional parameters of an aircraft wing rib strut includes:

[0007] Based on the thickness of the wing rib web Determine the thickness of the bottom edge of the wing rib support. ;

[0008] Calculate the minimum moment of inertia of the ribbed strut. ;

[0009] Calculate the minimum area of ​​the ribbed strut cross section ;

[0010] Calculate the top pressure load of the ribbed strut ;

[0011] Calculate the thermal stress load of the ribbed strut ;

[0012] Calculate the working stress of the ribbed strut section ;

[0013] Calculate the critical stress for instability of the ribbed strut section. ;

[0014] Calculate the safety margin of the wing-rib strut ;

[0015] The minimum moment of inertia of the rib support Minimum area of ​​wing-ribbed strut cross section Safety margin of wing ribs Under the constraint of greater than 0, find the area of ​​the cross section of the ribbed strut. Minimum width of the bottom edge of the wing-rib support Height of the web of the wing-rib strut Thickness of the web of the wing-rib support .

[0016] According to at least one embodiment of this application, in the above-described aircraft wing rib strut cross-sectional parameter design method, the area of ​​the wing rib strut cross-section is... ;

[0017] in,

[0018] The width of the bottom edge of the wing-rib support;

[0019] The height of the web of the wing-rib support;

[0020] The thickness of the web of the wing-rib support.

[0021] According to at least one embodiment of this application, in the above-described aircraft wing rib strut section parameter design method, the minimum moment of inertia of the wing rib strut... ;

[0022] in,

[0023] The average spacing between the wing-rib supports;

[0024] The distance between the centroids of the upper and lower edges of the wing rib;

[0025] is the shear buckling coefficient of the rib web.

[0026] According to at least one embodiment of this application, in the above-described aircraft wing rib strut cross-sectional parameter design method, the minimum area of ​​the wing rib strut cross-section is... .

[0027] According to at least one embodiment of this application, in the above-described aircraft wing rib strut section parameter design method, the top pressure load of the wing rib strut... , , ;

[0028] in,

[0029] , This refers to the distance between the two side wing rib supports and the corresponding inner stringers;

[0030] , The top pressure load on both sides of the long truss;

[0031] , The distance between the ribs on both sides;

[0032] , This refers to the area of ​​the two side stringers and their corresponding skins;

[0033] , The elastic modulus of the two side stringers;

[0034] , It is the distance from the axis of the two stringers to the centroid of the airfoil section.

[0035] According to at least one embodiment of this application, in the above-described aircraft wing rib strut cross-sectional parameter design method, the thermal stress load of the wing rib strut is... ,

[0036] in,

[0037] This refers to the thermal stress experienced by the wing-rib support.

[0038] According to at least one embodiment of this application, in the above-described aircraft wing rib strut section parameter design method, the working stress of the wing rib strut section is... .

[0039] According to at least one embodiment of this application, in the above-described aircraft wing rib strut section parameter design method, the critical stress for wing rib strut section instability is... :

[0040] like ,but ;

[0041] in,

[0042] The compressive strength of the rib support;

[0043] The effective length of the wing rib support;

[0044] The radius of gyration of the rib support;

[0045] like ,but ;

[0046] in,

[0047] The elastic modulus of the rib support;

[0048] The proportional limit for the wing rib support material;

[0049] like ,but .

[0050] According to at least one embodiment of this application, in the above-described aircraft wing rib strut cross-sectional parameter design method, the safety margin of the wing rib strut... .

[0051] According to at least one embodiment of this application, in the above-described aircraft wing rib strut cross-sectional parameter design method, the wing rib strut is T-shaped overall, and its minimum moment of inertia... Radius of gyration The thickness of its bottom edge Width of the bottom edge The height of the web Web thickness The function can be calculated using the usual calculation methods. Attached Figure Description

[0052] Figure 1 is a schematic diagram of the design method for the cross-sectional parameters of the aircraft wing rib strut provided in an embodiment of this application;

[0053] Figure 2 is a schematic diagram showing the wing rib struts and wing rib webs of an aircraft according to an embodiment of this application;

[0054] Figure 3 is a schematic diagram showing the aircraft wing ribs, stringers and their struts provided in the embodiments of this application.

[0055] To better illustrate this embodiment, some parts in the accompanying drawings may be omitted, enlarged, or reduced, and do not represent the actual size of the product. Furthermore, the accompanying drawings are for illustrative purposes only and should not be construed as limiting this patent. Detailed Implementation

[0056] To make the technical solution and advantages of this application clearer, the technical solution of this application will be described in a clearer and more complete manner below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only some embodiments of this application, and are only used to explain this application, not to limit this application. It should be noted that, for ease of description, only the parts related to this application are shown in the accompanying drawings. Other related parts can be referred to the general design. In the absence of conflict, the embodiments and technical features in the embodiments of this application can be combined with each other to obtain new embodiments.

[0057] Furthermore, unless otherwise defined, the technical or scientific terms used in this application description shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "upper," "lower," "left," "right," "center," "vertical," "horizontal," "inner," and "outer," etc., used in this application description to indicate relative direction or positional relationship are used only to indicate relative orientation or positional relationship, and do not imply that the device or component must have a specific orientation, or be constructed and operated in a specific orientation. When the absolute position of the described object changes, its relative positional relationship may also change accordingly, and therefore should not be construed as a limitation on this application. The terms "first," "second," "third," and similar terms used in this application description are used only for descriptive purposes to distinguish different components, and should not be construed as indicating or implying relative importance. The terms "a," "one," or "the," etc., used in this application description should not be construed as an absolute limitation on quantity, but should be construed as indicating the existence of at least one. The terms "including," "comprising," etc., used in this application description mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, without excluding other elements or objects.

[0058] Furthermore, it should be noted that, unless otherwise explicitly specified and limited, terms such as “installation,” “connection,” and “linkage” used in the description of this application should be interpreted broadly. For example, a connection can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; or it can be a connection within two components. Those skilled in the art can understand its specific meaning in this application according to the specific circumstances.

[0059] The present application will now be described in further detail with reference to Figures 1 to 3.

[0060] A method for designing the cross-sectional parameters of an aircraft wing rib strut, as shown in Figure 1, includes:

[0061] Based on the thickness of the wing rib web Determine the thickness of the bottom edge of the wing rib support. ;

[0062] Calculate the minimum moment of inertia of the ribbed strut. ;

[0063] Calculate the minimum area of ​​the ribbed strut cross section ;

[0064] Calculate the top pressure load of the ribbed strut ;

[0065] Calculate the thermal stress load of the ribbed strut ;

[0066] Calculate the working stress of the ribbed strut section ;

[0067] Calculate the critical stress for instability of the ribbed strut section. ;

[0068] Calculate the safety margin of the wing-rib strut ;

[0069] The minimum moment of inertia of the rib support Minimum area of ​​wing-ribbed strut cross section Safety margin of wing ribs Under the constraint of greater than 0, find the area of ​​the cross section of the ribbed strut. Minimum width of the bottom edge of the wing-rib support Height of the web of the wing-rib strut Thickness of the web of the wing-rib support As shown in Figure 2.

[0070] Regarding the aircraft wing rib strut cross-sectional parameter design method disclosed in the above embodiments, those skilled in the art will understand that its design is based on the thickness of the wing rib web. Determine the thickness of the bottom edge of the wing rib support. Based on this, calculate the minimum moment of inertia of the ribbed strut. Minimum area Top pressure load Thermal stress load Working stress Critical stress of cross-section instability Safety margin Therefore, the minimum moment of inertia of the wing rib support. Minimum area of ​​wing-ribbed strut cross section Safety margin of wing ribs Under the constraint of greater than 0, find the area of ​​the cross section of the ribbed strut. Minimum width of the bottom edge of the wing-rib support Height of the web of the wing-rib strut Thickness of the web of the wing-rib support That is, to find the width of the bottom edge of the wing support that minimizes the mass of the wing support. Height of the web of the wing-rib strut Thickness of the web of the wing-rib support The cross-sectional parameters of the ribbed strut were determined, including the thickness of the bottom edge of the ribbed strut. Width of the bottom edge of the wing rib support Height of the web of the wing-rib strut Thickness of the web of the wing-rib support .

[0071] In some optional embodiments, in the above-described method for designing the cross-sectional parameters of aircraft wing rib struts,

[0072] Based on the thickness of the wing rib web Determine the thickness of the bottom edge of the wing rib support. The details are as follows:

[0073]

[0074] In some optional embodiments, in the above-described aircraft wing rib strut cross-sectional parameter design method, the area of ​​the wing rib strut cross-section is... ;

[0075] in,

[0076] The width of the bottom edge of the wing-rib support;

[0077] The height of the web of the wing-rib support;

[0078] The thickness of the web of the wing-rib support.

[0079] In some optional embodiments, in the above-described aircraft wing rib strut section parameter design method, the minimum moment of inertia of the wing rib strut is... ;

[0080] in,

[0081] The average spacing between the wing-rib supports;

[0082] The distance between the centroids of the upper and lower edges of the wing rib;

[0083] is the shear buckling coefficient of the rib web.

[0084] In some optional embodiments, in the above-described aircraft wing rib strut cross-sectional parameter design method, the minimum area of ​​the wing rib strut cross-section is... .

[0085] In some optional embodiments, in the above-described aircraft wing rib strut section parameter design method, the top pressure load of the wing rib strut is... , , ;

[0086] in,

[0087] , This refers to the distance between the two side wing rib supports and the corresponding inner stringers;

[0088] , The top pressure load on both sides of the long truss;

[0089] , The average value of the distance between the ribs on both sides is [value missing]. ;

[0090] , This refers to the area of ​​the two side stringers and their corresponding skins;

[0091] , The elastic modulus of the two side stringers;

[0092] , The distance from the axis of the two stringers to the centroid of the airfoil section is shown in Figure 3.

[0093] In some optional embodiments, in the above-described design method for the cross-sectional parameters of the aircraft wing rib strut, the thermal stress load of the wing rib strut is... ,

[0094] in,

[0095] This refers to the thermal stress experienced by the wing-rib support.

[0096] In some optional embodiments, in the above-described aircraft wing rib strut section parameter design method, the working stress of the wing rib strut section is... .

[0097] In some optional embodiments, in the above-described aircraft wing rib strut section parameter design method, the critical stress for wing rib strut section instability is specified. :

[0098] like The ribbed support fails under short column compression, and its critical instability stress is its compression strength, which is obtained using the plate element method. ;

[0099] in,

[0100] The compressive strength of the rib support;

[0101] The effective length of the rib support is calculated based on the cross-sectional instability critical stress of the rib support. The end support is considered as hinged at both ends, and the support coefficient is taken as 1. The effective length of the rib support is numerically equal to its actual length.

[0102] The radius of gyration of the rib support;

[0103] like The ribbed struts fail due to Euler instability of the long column. The critical stress for instability of the cross section is calculated using Euler's formula. ;

[0104] in,

[0105] The elastic modulus of the rib support;

[0106] The proportional limit for the wing rib support material;

[0107] like The wing-ribbed support exhibits a combined instability failure due to compression loss in the short column and Euler instability in the long column. The critical instability stress of the cross section is calculated using the Johnson-Euler equation. .

[0108] In some optional embodiments, the safety margin of the wing rib strut cross-sectional parameters in the above-described aircraft wing rib strut design method is... .

[0109] In some optional embodiments, in the above-described design method for the cross-sectional parameters of the aircraft wing rib strut, the wing rib strut is T-shaped overall, and its minimum moment of inertia... Radius of gyration The thickness of its bottom edge Width of the bottom edge The height of the web Web thickness The function can be calculated using the usual methods, as detailed below:

[0110] ;

[0111] ;

[0112] .

[0113] The various embodiments in the specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0114] The technical solution of this application has been described in conjunction with the preferred embodiments shown in the accompanying drawings. Those skilled in the art should understand that the scope of protection of this application is obviously not limited to these specific embodiments. Without departing from the principles of this application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of this application.

Claims

1. A method for designing the cross-sectional parameters of an aircraft wing rib strut, characterized in that, include: Based on the thickness of the wing rib web Determine the thickness of the bottom edge of the wing rib support. ; Calculate the minimum moment of inertia of the ribbed strut. ; Calculate the minimum area of ​​the ribbed strut cross section ; Calculate the top pressure load of the ribbed strut. ; Calculate the thermal stress load of the rib support. ; Calculate the working stress of the ribbed support section ; Calculate the critical stress for instability of the ribbed strut section ; Calculate the safety margin of the ribbed strut ; minimum moment of inertia of the wing-rib support Minimum area of ​​wing-ribbed strut cross section Safety margin of wing ribs Under the constraint of greater than 0, find the area of ​​the cross section of the ribbed strut. Minimum width of the bottom edge of the wing-rib support Height of the web of the wing-rib strut Thickness of the web of the wing-rib support Top pressure load of rib struts ， ， ;in, 、 This refers to the distance between the two side wing rib supports and the corresponding inner stringers; 、 The top pressure load on both sides of the long truss; 、 The distance between the ribs on both sides; 、 This refers to the area of ​​the two side stringers and their corresponding skins; 、 The elastic modulus of the two side stringers; 、 The distance from the axes of the two stringers to the centroid of the airfoil section; the critical stress for instability of the wing rib strut section. :like ,but ;in, The compressive strength of the rib support; The effective length of the wing rib support; Let be the radius of gyration of the rib support; if ,but ;in, The elastic modulus of the rib support; The proportional limit of the rib support material; if ,but 。 2. The method for designing the cross-sectional parameters of an aircraft wing rib strut according to claim 1, characterized in that, Area of ​​the cross section of the ribbed strut ;in, The width of the bottom edge of the wing-rib support; The height of the web of the wing-rib support; The thickness of the web of the wing-rib support.

3. The method for designing the cross-sectional parameters of an aircraft wing rib strut according to claim 2, characterized in that, Minimum moment of inertia of ribbed struts ;in, The average spacing between the wing-rib supports; The distance between the centroids of the upper and lower edges of the wing rib; is the shear buckling coefficient of the rib web.

4. The method for designing the cross-sectional parameters of an aircraft wing rib strut according to claim 3, characterized in that, Minimum area of ​​ribbed strut cross section 。 5. The method for designing the cross-sectional parameters of an aircraft wing rib strut according to claim 4, characterized in that, Thermal stress load of rib strut ,in, This refers to the thermal stress experienced by the wing-rib support.

6. The method for designing the cross-sectional parameters of an aircraft wing rib strut according to claim 5, characterized in that, Working stress of ribbed strut section 。 7. The method for designing the cross-sectional parameters of an aircraft wing rib strut according to claim 6, characterized in that, Safety margin of wing rib strut 。

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