In this study, the surface wave interactions with submerged horizontal viscoelastic sheets of varying rheological properties are investigated both experimentally and analytically. In the experiments, we adopt the novel development in preparing finite length viscoelastic sheets with different rheological properties using oil-doped polydimethylsiloxane (PDMS) materials reported earlier in Sree et al. (2017, 2018). The wave interactions with the submerged viscoelastic sheets are quantified using ultrasonic sensors at different locations in terms of the reflection and transmission behavior. The experimental results show that the wave-sheet interactions are complex. The wave pattern at the submerged sheet region significantly depends on its rheological properties. For larger submergence, a standing wave pattern with primarily lower order modes develops along the sheet with a significant reduction of transmitted wave energy past the sheet region for shorter period waves. An almost complete cutoff (up to 99% reduction in wave energy transmission) occurs with the flexible sheet held close to the mean water level (MWL), while 50-90% reduction in wave energy transmission is recorded with the stiffer sheets. An analytical study is also carried out under the assumption of small amplitude water wave theory. The sheet is modeled based on the viscoelastic representation of the Voigt model and the analytical problem is solved using the domain matching technique. The profiles of surface wave as well as sheet displacement are well predicted by the analysis compared to the experimental measurements. However, the displacement amplitude is underestimated due to the fixed end conditions assumed. The predicted dispersion relation for the surface waves also agrees well with the experimental results for the shorter period waves, however larger discrepancies are observed with longer wave periods. In addition, the experimental results are up to one order of magnitude higher with respect to wave reflection. Thus, further improvement is needed in the future for the analysis to better represent the surface wave interactions with submerged viscoelastic sheets.

在这项研究中，通过实验和分析研究了具有不同流变特性的浸没水平粘弹性片的表面波相互作用。在实验中，我们采用了Sree等人先前报道的使用掺油的聚二甲基硅氧烷（PDMS）材料制备具有不同流变特性的有限长度粘弹性片材的新进展。（2017，2018）。使用超声波传感器在不同位置根据反射和透射行为来量化与浸没的粘弹性片材的波相互作用。实验结果表明，波片相互作用是复杂的。浸没板区域的波型很大程度上取决于其流变性。对于更大的淹没，沿薄板形成主要具有低阶模态的驻波图样，对于较短周期的波，穿过薄板区域的透射波能量显着降低。当将柔性片材保持在接近平均水位（MWL）时，发生了几乎完全的截止（波能传递降低多达99％），而较硬的片材记录了波能传递降低了50-90％。在小振幅水波理论的假设下也进行了分析研究。基于Voigt模型的粘弹性表示对工作表进行建模，并使用域匹配技术解决分析问题。与实验测量值相比，通过分析可以很好地预测表面波的轮廓以及板的位移。然而，由于假定的固定端条件，位移幅度被低估了。对于短波，表面波的预测色散关系也与实验结果非常吻合，但是对于长波，则观察到较大的差异。另外，相对于波反射，实验结果高出一个数量级。因此，将来需要进一步改进分析以更好地表示与水下粘弹性板的表面波相互作用。与波反射相比，实验结果要高出一个数量级。因此，将来需要进一步改进分析以更好地表示与水下粘弹性板的表面波相互作用。与波反射相比，实验结果要高出一个数量级。因此，将来需要进一步改进分析以更好地表示与水下粘弹性板的表面波相互作用。