Nonlinear Acoustics of Bounded Solid-Reflection and Refraction of Second-order Bulk Waves (I)——P Incidence~*
摘要
In the light of the theory of second-order potentials in nonlinear acoustics proposed by the author, this paper investigates the second-order harmonics resulting from an incident bulk wave in a solid with a plane boundary when the P, SV and SH waves are incident. It is shown that several bulk waves of the second-order harmonics occur in solid media besides second-order surface waves. Some of the waves are accumulated and some waves propagate in the direction parallel to the boundary surface. In order to obtain enough expressions for all the third-order elasticity constants, an SH-wave incidence is necessary in addition to the P and SV wave ones. It is pointed out that the contribution of the nonaccumulative waves and the waves resulting from the boundary surface are very important for measuring the nonlinear wave fields.