Vortex transportation and wave deformation after the interaction of a solitary wave with an inclined bottom mounted plate. (September 2018)

• Record Type: Journal Article
• Authors: Chang, Chih-Hua; Wang, Keh-Han; Lin, Chang; Jaf, Jassim M.
• Is Part Of: Applied ocean research. Volume 78(2018)
• Page Start: 241
• Page End: 253
• Publication Date: 2018-09
• Subjects: Solitary wave -- Inclined plate -- Vortical flow -- Streamfunction-vorticity formulations -- Flow visualizations; Ocean engineering -- Periodicals; 620.416205
• DOI: 10.1016/j.apor.2018.06.012
• Languages: English
• ISSNs: 0141-1187

Abstract

Highlights: A combined numerical and experimental investigation on the induced flow motions and free-surface deformations as a solitary wave propagating over a bottom mounted tilting thin plate. A downstream tilting plate has a greater effect on the wave-peak attenuations. The strongest primary vortex occurs within the tilting angles of −30° to −10° depending on the setting of plate height. Abstract: This study is aimed to investigate numerically and experimentally the interaction between a solitary wave and a thin submerged plate with various inclinations. The obtained results on wave deformations and formed vortex patterns are analyzed. To extend the very limited study on a solitary wave encountering an inclined plate, the developed streamfunction-vorticity formulations with free surface (SVFS) model is applied to compute the flow field, wave profiles, and induced forces. In addition, the experimental measurements of wave elevations and flow visualizations using particle image velocimetry (PIV), particle-tracking, and planar laser-induced fluorescence (PLIF) were conducted. This paper presents qualitative and quantitative comparisons between numerical solutions and experimental data, including the recorded images. The agreements are generally good. The influence of tilting angle, ranging from −60° to 60°, on the flow patterns, formed vortices, and free-surface elevations are examined and discussed. For a given incident wave and the setting of the same vertical level of the plate tip, it is found that the wave attenuations under a plate with a downstream tilting angle (positive angle) is larger than that when a plate is placed with an upstream tilting angle (negative angle). Also, the occurrence of maximum intensity of the main vortex is observed to be within the tilting angles of −30° to −10° depending on the setting of the plate height. In terms of hydrodynamic forces, when keeping the same tilting angle, the results suggest the maximum horizontal force per unit width on a downstream tilting plate is larger than that on an upstream tilting plate.