CosmosWorks算法验证文件 3 (Static Analysis and Mode-frequency Analysis)

tigerdak

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# H+ q; [/ P2 l4 B' N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。

4 G7 x# l$ n6 P5 GTitle     Vibration of a String Under Tension

2 B; A0 N0 }- G- J2 y2 eOverview

Reference:	W. T. Thomson, Vibration Theory and Applications, 2nd Printing, Prentice-Hall, Inc., Englewood Cliffs, NJ, 1965, pg. 264, article 8.2.
Analysis Type(s):	Static Analysis Mode-frequency Analysis

* ]% _$ a5 w5 m5 N2 L. G- {8 uTest Case
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A flexible string with mass per unit length ρA is fixed at the ends and stretched to an initial strain εo. Determine the stress σ and force F in the string under these conditions. Determine the first three natural frequencies fi of lateral vibration of the stretched string.

3 W% Y0 u$ b9 s- S- \Figure 53.1  String Under Tension Problem Sketch
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Material Properties E = 30 E6 psi ρ = 0.00073 lb-sec2/in4

Geometric Properties l = 100 in A = 0.00306796 in2

Loading εo = 0.00543228

Analysis Assumptions and Modeling NotesEnough elements are selected so that the same model can be used to adequately characterize the dynamic analysis. Prestress effects are turned on during the static and modal solutions.
The subspace method for eigenvalue extraction is chosen solely for the sake of completeness in this manual. Other methods would also be suitable. Only the first three modes are requested.

1 i1 L& G7 W- H; b+ N. bResults Comparison

		Target	ANSYS	Ratio
Static	F, lb	500.	500.	1.000
	Stress, psi	162,974.	162,970.	1.000
Modal	f1 , Hz	74.708	75.094	1.005
	f2 , Hz	149.42	151.29	1.012
	f3 , Hz	224.12	229.68	1.025

/ g) h& M" w5 B* f& i[ 本帖最后由 tigerdak 于 2007-11-9 15:29 编辑 ]

yong85nan

兄弟，这些哪里都有的资料就别浪费论坛的空间吧。
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, L3 o5 C* r6 H+ C6 o: t, [而却分了如此多个主题，应该一次就好了吧。:L
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真的是。。。。。哎。。。。。:L
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反省反省