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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。0 ]2 n6 I, d$ J. i; q4 P V
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Title Vibration of a Rotating Cantilever Blade9 K/ L4 D$ D) [- G
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Overview, Y: s' Z$ z+ F' }0 D9 M$ @1 M: k+ \1 N
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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 ' ?0 M S, j8 _0 ]) @. Z
Mode-frequency Analysis
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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 .3 n9 `; H: u4 w; t- [
8 m6 q* _4 f! Y4 ?( a* y% P1 {Figure 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 |
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Analysis Assumptions and Modeling NotesThe problem is solved in two different ways:
5 [+ Q! q8 X9 ~# W" F) I& g- Using Elastic Shell Elements (SHELL63)
- Using 3-D Solid Shell Elements (SOLSH190)
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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.* U7 m" @# _* K5 i5 P. }. ~, t' F* v
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Results Comparison6 k. C5 r' i1 D
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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 | 0 |9 o2 I! _$ @7 D- L! D
5 a7 Q" j4 A0 e[ 本帖最后由 tigerdak 于 2007-11-9 15:25 编辑 ] |
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