Host: The Japan Society of Mechanical Engineers
Name : Dynamics and Design Conference 2019
Date : August 27, 2019 - August 30, 2019
It is necessary to estimate noise generated from various machines for noise control. The vibration analysis of structures is important to estimate noise power radiating from the structures. Almost machines are composed of not only simple flat plate but also thin plate structures which has a convex. In general, the vibration analysis of these structures can be achieved by FEM. However, FEM is not suitable for structural optimization to reduce vibration or noise because of its huge calculation cost. In this paper, a new analysis of these structures with the Rayleigh-Ritz method is proposed so as to reduce calculation cost. Two models for vibration analysis using the summation of multiplication of eigenfunctions of Euler beam as trial function. First model called as “the adding beams model” which the boundary of convex changes to beams is introduced and its strain energy and kinetic energy of beams by bending and twisting are additionally calculated. Second model called as “the convex strain model” in which the strain by bending and stretching of upper plane and side-wall of convex are taken into account is introduced. Through these two models, the approximate vibration analysis of convex plate can be achieved. The calculated natural frequencies and mode shapes of the proposed analysis are compared with those obtained with a commercial FEM software (ANSYS). The result of the adding beam model agrees well with that of FEM. On the other hand, the result of the convex strain model has large error because the trial functions may not be enough to represent the model shape of plate with a convex.
