Page 30 - Using ANSYS for Finite Element Analysis Dynamic, Probabilistic, Design and Heat Transfer Analysis

Dynamic analysis • 17
The following window will appear:

Select UY as the 1st degree of freedom (shown above). The same
constraints are used as above.
The following table compares the mode frequencies (in Hz) pre-
dicted by theory and ANSYS (Reduced).

Mode Theory ANSYS Percent error
1 8.311 8.300 0.1
2 51.94 52.01 0.1
3 145.68 145.66 0.0
4 285.69 285.71 0.0
5 472.22 473.66 0.3

As you can see, the error does not change significantly. However,
for more complex structures, larger errors would be expected using the
reduced method.