In this paper, a series of numerical experiments are carried out on the anti-scour device combined with perforated baffle and ring-wing plate. addition, optimal dimensions location obtained: The ratio is S = 20%, distance from center bridge pier L 2d (d diameter pier), plate located at H 1/3h (h water depth). To verify effect device, scour characteristics flow field further investigated. Compar...

We analyze quasi-phase-matched (QPM) conversion efficiency of the five possible types of periodic two-dimensional nonlinear structures: Hexagonal, square, rectangular, centered-rectangular, and oblique. The frequency conversion efficiency, as a function of the two-dimensional quasi-phase-matching order, is determined for the general case. Furthermore, it is demonstrated for two basic feasible m...