The radiation impedance and the energy partition among wave fields generated by a normal force strip radiator on isotropic solid surface

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The radiation impedance and the energy partition among wave fields generated by a normal force strip radiator on isotropic solid surface

The radiation impedance and energy partition among elastic waves generated by a normal force strip radiator on an isotropic solid surface are investigated in this paper. Two methods are used to obtain the radiation energy. One is to get the total radiation energy from the radiation conductance. And the other is to get energy of all elastic waves at far field. The results indicate: (1) the energy ratio of the compressional wave increases with the width of the radiator becoming wider; (2) the energy of each elastic wave is nearly same while the width of the radiator changes in a some small range; (3) for different width of the strip radiator, the total energy gotten from the radiation conductance is equal to the energy sum of all waves gotten at far field. This not only proves the conservation of the energy wnile generating elastic waves,but also mutually reflects that approximate expressions of wave fields obtained from the method of the steepest descent are correct.