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

tigerdak

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. [" {- \' z0 a8 F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。

Title      Vibration of a Rotating Cantilever Blade
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Reference:	W. Carnegie, “Vibrations of Rotating Cantilever Blading”, Journal Mechanical Engineering Science, Vol. 1 No. 3, 1959, pg. 239
Analysis Type(s):	Static Analysis Mode-frequency Analysis

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6 C& U- h9 H1 f5 N6 C6 ]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 .
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" \' b' ]1 p; X6 a) r5 a9 T2 gFigure 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

' B, x& f2 h* T0 tAnalysis Assumptions and Modeling NotesThe problem is solved in two different ways:

• Using Elastic Shell Elements (SHELL63)
• Using 3-D Solid Shell Elements (SOLSH190)

" Y4 K' l/ g) X$ G6 b) w$ gSpin (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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Results 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

[ 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。