Band gaps and localization of surface water waves over large-scale sand waves with random fluctuations

Abstract

Band structure and wave localization are investigated for sea surface water waves over large-scale sand wave topography. Sand wave height, sand wave width, water depth, and water width between adjacent sand waves have significant impact on band gaps. Random fluctuations of sand wave height, sand wave width, and water depth induce water wave localization. However, random water width produces a perfect transmission tunnel of water waves at a certain frequency so that localization does not occur no matter how large a disorder level is applied. Together with theoretical results, the field experimental observations in the Taiwan Bank suggest band gap and wave localization as the physical mechanism of sea surface water wave propagating over natural large-scale sand waves.

Whitecap features induced by submarine sand waves in stereo optical imagery

“…As a result, sea surface waves in the SWA break more easily than those in the BGA. The simulated results qualitatively explain the differences between the observed whitecap coverage and the estimated probability of wave breaking in the SWA and BGA; (4) we further analyze the physical modulation mechanism based on the band structure and the localization system [Zhang et al, 2012]. The periodic sand wave system plays the role of a frequency-control device, such as a filter, and as a result, more broken waves are concentrated in the SWA.…”

“…Whereas, the threshold angle of 2.08 in the SWA is an unacceptable value, and another physical modulation mechanism is required to enhance wave breaking in SWA. Zhang et al [2012] studied the band gaps and localization of surface water waves over large-scale sand waves. They considered that sand waves can be seen as a group of periodical array pools under water, and discussed the influence of the periodic sand wave structure to wave propagation.…”

Broadband omnidirectional absorption for linear liquid surface wave

“…The OA suggests a variety of potential applications such as wave shielding, energy absorption, and energy collection. The linear liquid surface wave [17][18][19][20][21][22] (LLSW), as another important type of classical waves, also has various interesting physical properties such as superlensing [17], band gap [18,19], negative effective gravity [20], and focusing [22]. Besides, it is well known that rich energy is stored in the LLSW of oceans, which is considered as one of the clean renewable energy to defuse the incoming energy crisis.…”

Enhancement of Sea Wave Potential Energy with Under-Sea Periodic Structures: A Simulation and Laboratory Study

“…Therefore, doubling the wave amplitude using the under-sea structure would yield a quadruple increment of the efficiency. Recently, there have been proposals to utilize periodic structures to concentrate light waves, sound waves and water waves [15][16][17][18][19][20][21][22][23][24][25]. In our previous studies, we have pointed out that by optimizing the constraints of periodic arrangement, surface waves can be enhanced when propagating over periodic structures [26].…”