Dynamic stress concentrations in piezoelectric materials with semi-elliptical surface notches under shear horizontal waves
摘要
Dynamic loading causes high stress concentrations at surface notches, which are further aggravated by piezoelectric effects. This research presents a novel semi-analytical technique for studying dynamic stress concentrations in semi-elliptical surface notches in piezoelectric materials subjected to shear horizontal (SH) wave incidence. The mirror technique is employed to apply traction-free and electrically insulating boundary conditions, converting the half-space problem into its analogous full-space form. Mathieu functions and elliptical coordinate system are adopted to model the geometry of the semi-elliptical notch accurately. By separating the governing equations, the potential function is obtained, and boundary conditions are applied to construct an infinite set of linear algebraic equations. To ensure reliability of the solution, a truncation scheme based on Mathieu function convergence behavior is proposed before solving the system. Numerical simulations are performed with a thorough parametric study to reveal the effects of important parameters like the incidence angle of waves, wave frequency, notch depth, and piezoelectric material characteristics on the behavior of scattered wave fields and dynamic stress concentrations. The presented model enjoys wide geometric applicability, provides necessary theoretical guidelines for the design of piezoelectric elements and serves as a baseline for the validation of computational approximations.