CosmosWorks算法验证文件 7 (Mode-frequency Analysis )

tigerdak

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3 w# b0 k& m8 A* V* y# F& V4 q提示：如果分析得出第一阶频率接近72.059就可以了，因为CosmosWorks（2006）在频率分析时没有办法设置旋转刚度软化的影响，所以不会得到后面那个target值。

1 s! t/ V2 f, P6 ^+ C% v$ BTitle      Vibration of a Rotating Cantilever Blade
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Overview

Reference:	W. Carnegie, “Vibrations of Rotating Cantilever Blading”, Journal Mechanical Engineering Science, Vol. 1 No. 3, 1959, pg. 239
Analysis Type(s):	Static Analysis $ C: ~0 o, n7 ]0 g' KMode-frequency Analysis

4 x7 m1 u9 _! o) J/ B# m! k; bTest Case
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A blade is cantilevered from a rigid rotating cylinder. Determine the fundamental frequency of vibration of the blade, f, when the cylinder is spinning at a rate of Ω .

& \6 p( z2 I5 {+ G9 }7 r+ w  p( bFigure 54.1  Rotating Cantilever Blade



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Material Properties E = 217 E9 Pa ρ = 7850 kg/m3 υ = 0.3

Geometric Properties r = 150 mm l= 328 mm b = 28 mm t = 3mm

Loading Ω = 100π rad/sec

1 |6 S4 ~, U' E' v$ o1 P. u. ~Analysis Assumptions and Modeling NotesThe problem is solved in two different ways:
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• Using Elastic Shell Elements (SHELL63)
• Using 3-D Solid Shell Elements (SOLSH190)

9 U/ n5 z7 Q' W* n' SSpin (centrifugal) softening is used. Since the cylinder is rigid, the base of the blade has its displacements constrained. A static prestress analysis is performed to include the inertial effects resulting from the rotation of the cylinder.
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. t" z& ~) Q+ w4 BResults Comparison
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	Target	ANSYS	Ratio
SHELL63
f, Hz	52.75	52.01	0.986
SOLSH190
f, Hz	52.75	51.80	0.982

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8 }. z# B6 j5 U% s' ^  z) ?" t% L% I[ 本帖最后由 tigerdak 于 2007-11-9 15:25 编辑 ]

tigerdak

都不考虑旋转刚度软化的情况下，在偶的机器上CosmosWorks是72.059，ANSYS是72.060。