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; s8 K, g0 j! |这是我从ANSYS的算法验证文件转换过来的,同样适用于CosmosWorks。在计算实际的工程问题以前应该先计算一个类似的验证文件,比较计算结果以验证自己算法的正确性。也可以作为有限元例题使用。
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(提示:CosmosWorks里没有直接模拟弹簧的单元,但是可以通过材料的弹性模量来模拟弹簧的刚度,k=EA/L)
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: C; G* r" Z. v4 S! P3 n; |Title Natural Frequency of a Spring-Mass System, s: V. e% ^, U0 E9 a7 C
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| Reference: | W. T. Thomson, Vibration Theory and Applications, 2nd Printing, Prentice-Hall, Inc., Englewood Cliffs, NJ, 1965, pg. 6, ex. 1.2-2. | | Analysis Type(s): | Mode-frequency Analysis | " S1 ]* [. O8 k/ x% T7 y- V& Y# l
Test Case
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An instrument of weight W is set on a rubber mount system having a stiffness k. Determine its natural frequency of vibration f.) T( p k: m) l1 i& L: F7 t
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Figure 45.1 Spring-mass System Problem Sketch k1 L; |! D7 m1 K# @
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' _% d' b! x& f7 q1 P" u| Material Properties | | k = 48 lb/in | | W = 2.5 lb |
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Analysis Assumptions and Modeling NotesThe spring length is arbitrarily selected. One master degree of freedom is chosen at the mass in the spring length direction. The weight of the lumped mass element is divided by gravity in order to obtain the mass. Mass = W/g = 2.5/386 = .006477 lb-sec2/in.
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Results Comparison | Target | ANSYS | Ratio | | f, Hz | 13.701 | 13.701 | 1.000 |
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[ 本帖最后由 tigerdak 于 2007-11-6 12:03 编辑 ] |
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