This study intends to improve the machinery properties by reducing the weight of the converter without changing the dynamic characteristics.
At first, the Vibration analyses by the Substructure Synthesis Method and by F.E.A using the ANSYS are performed for the converter model to confirm the reliability of the analyzing tools. Weight minimization is performed by the Sensitivity Analysis and the Optimum Structural Modification.
To decrease the converter weight ideally, the weight parts with low sensitivity is to be cut mainly, and the changing quantity of the natural frequency by the cut is to be recovered by the weight modification of the parts with high sensitivity.
Mathematically unique solution for the homogeneous problem( i. e. 0 object function problem) does not exist, then the converter is redesigned with much thinner initial thickness, The natural frequencies and natural modes of original structure by the sensitivity analysis, and then observed the Frequency Response Functions(FRF) are observed for some interesting points.
In this analysis, the original thickness of the converter model is 84 mm, and the redesigned initial thickness is 60 mm and 70 mm. And the numbers of the interesting natural frequencies are 1, 2, 4 respectively.
The results are as follows :
(1) The weight for the each case could be reduced without changing the objective natural frequencies.
(2) According to the exciting frequency range of the converter, effective weight minimization is possible. For the case of narrow frequency band, weight reduction effect is higher than that of wide frequency band's.
(3) The method could be applied not only for the weight minimization, but also for the improvement of dynamic characteristics of the converter.