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Method for determining flutter velocity of slender ship based on transfer function

A technique for determining methods and slender bodies, applied in electrical digital data processing, special data processing applications, instruments, etc., can solve problems such as reduced accuracy of calculation results

Inactive Publication Date: 2017-01-11
河北新途科技有限公司 +1
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  • Application Information

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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 the vibration of the slender body is reduced, and the actual vibration of the slender body is approximated, which reduces the accuracy of the calculation results

Method used

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  • Method for determining flutter velocity of slender ship based on transfer function
  • Method for determining flutter velocity of slender ship based on transfer function
  • Method for determining flutter velocity of slender ship based on transfer function

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Embodiment 1

[0106] as attached Figure 1-5 Shown, embodiment 1 of the present invention is as follows:

[0107] A slender body is 1.8 meters long, weighs 22 kilograms, and has a maximum cross-sectional diameter of 0.025 square meters.

[0108] The specific calculation steps of the present embodiment 1 are as follows:

[0109] Step (1): Divide the slender body into 10 units, and measure the following physical parameters of each unit node of the slender body:

[0110] Axial length of each unit: l 1 = l 2 =…=l 10 =0.18, the unit is meter;

[0111] Cross-sectional area at each element node: A 1 =0,A 2 =A 3 =…=A 10 =0.025,A 11 =0.02, the unit is meter 2

[0112] Mass per unit length m at nodes of each element 1 =10,m 2 =m 3 ...=m 10 =20, the unit is kilogram / meter;

[0113] Bending stiffness EI at the nodes of each element 1 =0.5×10 3 , EI 2 =…=EI 11 =1.1×10 3 , in Newton meters 2 ;

[0114] Air density ρ=1.225, the unit is kg / m 3 ;

[0115] Step (2): Determine the ai...

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Abstract

The invention relates to a method for determining flutter velocity of a slender ship based on transfer function, and belongs to the technical field of aeroelesticity of flight vehicles. The method comprises the following steps: 1, obtaining a differential equation of the flutter of the slender ship through a differential equation of transverse bending vibration of beams and a model of a quasi-steady aerodynamic force of the slender ship. 2, dispersing the slender ship into slender ship units, and then proceeding Fourier conversion of the differential equation of the flutter of the slender ship units within the units, and 3, the flutter velocity of the slender ship is solved further by the transfer function. According to the method for determining flutter velocity of a slender ship based on transfer function, instead of adopting the low-order mode of the transverse vibration of the beams to describe approximately the vibration of the slender ship, differential equation of transverse bending vibration of beams is adopted to describe accurately the transverse vibration of the slender, therefore the flutter velocity of the slender ship calculated is more accurate. Compared with the prior technology, the method for solving the flutter velocity of the slender ship is much simpler.

Description

technical field [0001] The invention relates to a method for determining the flutter velocity of a slender body based on a transfer function, and belongs to the technical field of aircraft aeroelasticity. Background technique [0002] For aircraft fuselage, missile body, wing external rocket, etc., when the slenderness ratio is large (generally greater than about 10), it is called a slender body. Slender body flutter refers to the dynamic instability that occurs in the flight of the aircraft, and the flight speed at this time is called the 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 analyzing and calculating the flutter of a slender body, on the one han...

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): G06F19/00
CPCG16Z99/00
Inventor 段静波江涛王龙路平蔚建斌邱金刚史风鸣
Owner 河北新途科技有限公司
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