| 摘要 |
PROBLEM TO BE SOLVED: To accurately perform vibration analysis of an extremely low plate-like structure using a general computer by repeatedly calculating the natured feguency of a plate-like structure model until the natural fregnency coincidies with that of a detailed model while changing parameters. SOLUTION: A theree-dimensional finite element model (a detailed model) is prepared by dividing all members of a structure into finite elements (first former half of S1). Next, a plate-like structure model is prepared by modeling a two-dimensional plate structure (first half of S2). Then, a plate-like structure model equivalent to the detailed model is identified while changing model variables of the plate-like structure model (second half of S2 to S6.) Next, analysis of an intrinsic value of the plate-like structure model isperformed (S3) and the natural frequency of (fN-eq- Bend ) for bending deformation is compared with the natural frequency (fN- Bend ) of the detailed model (S4). When the natural frequency are not coincident, an equivalent shearing elastic coefficient is changed (S5), the natural frequency(fN-eq- Tor ) of torsion deformation is further compared with the natural frequency (fN- Tor ) of the detailed model (S5), thickness of a plateis changed (S7) and such operation is repeated until the natural frequency coincide. |
