OS-V: 0400 Pin-ended Double Cross
Test No. FV2 A pin-ended double cross, in-plane vibration problem. OptiStruct is used to investigate the coupling between flexural and extensional behavior, as well as the repeated and closed eigenvalues of the double cross in Normal Modes Analysis.
Model Files
Benchmark Model
The 2-node simple beam elements are used to model the double cross. Each arm of the cross consists of four elements. The x- and y-translation displacements are fixed at the end of all arms.
- Property
- Value
- E
- 200 x 109 N/m2
- 8000 kg/m3
Modal Analysis Results
f*
- Closed form solution
Mode 1 | Modes 2 and 3 | Modes 4, 5, 6, 7 and 8 | |||
---|---|---|---|---|---|
f* CBAR |
11.336 Hz 0.9984 |
f* CBAR |
17.709 Hz 0.9958 |
f* CBAR |
17.709 Hz 0.9974 |
Mode 9 | Modes 10 and 11 | Modes 12, 13, 14, 15 and 16 | |||
---|---|---|---|---|---|
f*
CBAR |
45.345 Hz 1.0000 |
f* CBAR |
57.390 Hz .9944 |
f* CBAR |
57.390 Hz 0.9999 |
Reference
NAFEMS R0015 - Selected benchmarks for natural frequency analysis