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Detail fatigue rating (DFR) reference value determination method for folding direction connection structure stress in different phases

A technique of maximum tensile and shear stress, which is applied in the field of aviation fatigue calculation, can solve unrelated, different and equal problems, achieve simple steps, expand the calculation range, and facilitate computer programming

Active Publication Date: 2015-04-08
XIAN AIRCRAFT DESIGN INST OF AVIATION IND OF CHINA
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Problems solved by technology

The fatigue load spectrum of the aircraft structure is composed of various load situations that may be encountered in the actual flight of the aircraft. Generally speaking, the maximum tensile stress and the maximum shear stress in the fatigue load spectrum are not in phase (that is, the two do not appear at the same time) , the existing DFR (structural detail fatigue rating) calculation method cannot truthfully reflect the influence of the above factors
[0003] Existing relevant patent literature does not relate to the problem described in the present invention

Method used

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  • Detail fatigue rating (DFR) reference value determination method for folding direction connection structure stress in different phases
  • Detail fatigue rating (DFR) reference value determination method for folding direction connection structure stress in different phases
  • Detail fatigue rating (DFR) reference value determination method for folding direction connection structure stress in different phases

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Embodiment Construction

[0030] The present invention will be described in further detail below in conjunction with accompanying drawing, please refer to Figure 1 to Figure 3 .

[0031] Such as figure 1 As shown, it is a schematic diagram of the spanwise connection structure. The spanwise connection structure is composed of 1-left skin, 2-right skin, 3-fasteners, and 4-long truss. This structural form is widely used It is used in aircraft structures such as wing-skin butt joints and fuselage skin butt joints.

[0032] Such as figure 2 As shown in , it is a schematic diagram of the dimensions of the spanwise connection structure, and the relevant parameters used in the example are given.

[0033] Such as image 3 Shown is the fatigue stress profile, which is used in the example, and is composed of 6 load cases.

[0034] A method for determining the DFR reference value when the maximum tensile stress and the maximum shear stress of a spanwise connection structure are out of phase, comprising the ...

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Abstract

The invention belongs to the field of aviation fatigue calculation, in particular to a detail fatigue rating (DFR) reference value determination method for folding direction connection structure stress in different phases. The DFR reference value determination method when the maximum tensile stress and the maximum shearing stress are in different phases is provided for folding-direction connection structures generally used by airplane structures, the premise that the maximum tensile stress and the maximum shearing stress are identical is avoided, and a calculation range of an original method is expanded. The DFR reference value determination method can be obtained based on airplane structure actual fatigue load spectrums so as to be more suitable for actual flying and stress situations. The DFR reference value determination method for folding direction connection structure stress in different phases is clear in theory basis, convenient in steps and capable of enabling computer programming to achieve automation easily.

Description

technical field [0001] The invention belongs to the field of aviation fatigue calculation, in particular to a method for determining a DFR reference value when the maximum tensile stress and the maximum shear stress of a spanwise connection structure are in different phases. Background technique [0002] The spanwise connection structure is a typical connection structure commonly used in structures, and it is often used in the butt joint of wing panels and the connection of fuselage panels. When the existing connection form uses the DFR (structural detail fatigue rating) method to calculate the fatigue strength, it is assumed that the maximum tensile stress and the maximum shear stress in the fatigue load spectrum are in phase (that is, both appear simultaneously) , which simplifies the calculation process. The fatigue load spectrum of the aircraft structure is composed of various load situations that may be encountered in the actual flight of the aircraft. Generally speaki...

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Application Information

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Patent Type & Authority Patents(China)
IPC IPC(8): G01M99/00
Inventor 张彦军李小鹏翟新康雷晓欣
Owner XIAN AIRCRAFT DESIGN INST OF AVIATION IND OF CHINA
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