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Determination Method of Wing Flutter Velocity Based on Transfer Function

A transfer function, determination method technology, applied in electrical digital data processing, special data processing applications, instruments, etc., can solve problems such as reducing the degree of freedom of wing vibration and reducing the accuracy of calculation results

Inactive Publication Date: 2017-09-05
PEOPLES LIBERATION ARMY ORDNANCE ENG COLLEGE
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Therefore, the disadvantage of the above calculation method is: in order to avoid too complicated calculation, the degree of freedom of wing vibration is reduced, and the actual vibration of the wing is approximated, which reduces the accuracy of the calculation results.

Method used

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  • Determination Method of Wing Flutter Velocity Based on Transfer Function
  • Determination Method of Wing Flutter Velocity Based on Transfer Function
  • Determination Method of Wing Flutter Velocity Based on Transfer Function

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Embodiment 1

[0080] In order to further illustrate the method of the present invention, this embodiment 1 is compared with the calculation result (Vcz=36.6 m / s) of the reference (Zhao Yonghui's monograph "Aeroelasticity and Control", Beijing: Science Press, 2006).

[0081] The specific calculation steps of the present embodiment 1 are as follows:

[0082] Step (1): adopt the physical parameter (seeing table 1 below) of the used long straight wing among the above-mentioned references:

[0083] Table 1 Physical parameters of long straight wing

[0084]

[0085] Step (2): Determine the airspeed V of the aircraft wing and the approximate range of the circular frequency ω as Division step Calculate the values ​​of Re[detA] and Im[detA] according to step (3) to step (7) in the summary of the invention. image 3 and Figure 4 given in Contour plots of Re[detA] and Im[detA] in the range. Figure 5 gives image 3 and Figure 4 composite image. from Figure 5 can be found in the give...

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Abstract

The present invention relates to an aerofoil flutter speed determining method based on a transfer function. According to the aerofoil flutter speed determining method, an aerofoil flexural-torsional oscillatory differential equation and a Theodrosen unsteady aerodynamic model are utilized to obtain a long and straight aerofoil flutter differential equation, then Fourier conversion is performed on the aerofoil flutter differential equation, and the transfer function is used to solve the aerofoil flutter speed. The aerofoil flutter speed determining method has the beneficial effects as follows: (1) as the aerofoil flexural-torsional oscillatory differential equation is utilized to accurately describe the aerofoil oscillation and a low-order mode of the aerofoil oscillation is not adopted to approximately describe the aerofoil oscillation, the calculated aerofoil flutter speed is more accurate; and (2) compared to the prior art, the aerofoil flutter speed solving method is simpler.

Description

technical field [0001] The invention relates to a method for determining wing flutter velocity based on a transfer function, and belongs to the technical field of aircraft aeroelasticity. Background technique [0002] Wing flutter refers to the dynamic instability that occurs during aircraft flight, and the flight speed at this time is called flutter speed. Most of the self-excited vibrations that occur when flight reaches flutter speeds are disastrous. Flutter analysis is to find out the conditions of flutter, that is, to find out the flutter speed, and seek measures to avoid flutter within the flight speed range of the aircraft, and then find ways to increase the critical speed of flutter. [0003] When performing wing flutter analysis and calculation, on the one hand, it is necessary to know the dynamic characteristics of the wing structure, and on the other hand, it is necessary to know the aerodynamic characteristics of the unsteady flow near the wing structure. At pr...

Claims

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Application Information

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Patent Type & Authority Patents(China)
IPC IPC(8): G06F17/50
CPCY02T90/00
Inventor 段静波江涛路平蔚建斌邱金刚左军
Owner PEOPLES LIBERATION ARMY ORDNANCE ENG COLLEGE
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