NONLINEAR RESONATOR WITH PORES AS INHOMOGENEITIES |
| 1 | |
| 2013 |
| scientific article | 534.222 | ||
| 224-229 | rubber-like medium, cubic nonlinearity, shear elasticity, standing waves, resonator, structure inhomogeneity |
| Shear waves of finite amplitude are studied in a rubber-like layer with inhomogeneities represented by through pores made on the side faces. The pores are parallel to the bases and perpendicular to the oscillations. Their centres are shifted to one of the bases that lets one to study 2 different configurations of the resonator with pores at the bottom and the top. A rigid plate of finite mass is mounted on the top surface of the layer. The bottom border of the layer oscillates harmonically with given acceleration. The equation of particles motion in the resonator was found using the medium with a single relaxation time model and a cubic dependence of the shear modulus of deformation. Amplitude and shape of the shear waves in the resonator were calculated by the finite difference method on shifted grids. The measurements were performed in a resonator represented by rectangular parallelepiped made of 15 mm thick rubber-like polymer plastisol. Inhomogeneities had square cross-section with 5 mm side. The amplitudes of the oscillations in the resonator reached the point where the maximum shear strain in the resonator is 0.4 - 0.6, which allowed to observe nonlinear effects. The top bound acceleration resonance curves were measured at different acceleration amplitudes of the bottom bound. Harmonic analysis of wave profiles was conducted and it showed that nonlinear effects are most pronounced in the resonator with cavities located in the region of maximum deformation. |
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