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

tigerdak

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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

Overview
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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 1 J6 N+ H% \" q: S: o3 kMode-frequency Analysis

' x0 \4 H+ q: rTest Case

* N: E3 M4 h7 _& L( g8 {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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; l) _7 O6 T' ?7 r( O- ]2 rFigure 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

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)

Spin (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

	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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[ 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。