论文标题
嵌入式捕获模式的两个引导波的总反射
Total reflection of two guided waves for embedded trapped modes
论文作者
论文摘要
为了研究波捕获的机理，通过反馈回路闭合原理计算了与两维管道腔内结构中与两谐模式干扰相关的声学嵌入式捕获模式，这使我们能够分析构建捕获模式的行进模式。在几个数值上证明了嵌入式捕获模式的确切的两个共振模式，该模式在开放到两个半无限管道的空腔中得到了数值证明。在空腔段和管道之间的界面上，对于两个腔中两个繁殖引导波的特定组合可能会发生总反射。在特定的空腔长度和特定频率的情况下，在腔的另一端的两个反射波也发生了总反射。这样，这两个共存的站立波是一个被困模式的基础。发现这两个站立波不是两个闭合腔模式。因此，这项工作对这种嵌入式捕获的模式提出了新的理解，是两个波导之间的界面上两个引导波的总反射的乘积，而不是在封闭腔的两个特征码之间的干扰。对于准捕获的模式，还显示了由于两个声通道的影响，Fano散射现象。
To investigate the mechanism of wave trapping, acoustic embedded trapped modes associated with two-resonant-mode interference in two-dimensional duct-cavity structures are calculated by the feedback-loop closure principle, which allows us to analyse the travelling modes that construct the trapped modes. The exact two coexisting resonant modes that underpin an embedded trapped mode in a cavity open to two semi-infinite ducts are numerically demonstrated. At the interface between the cavity segment and a duct, total reflection can occur for a particular combination of two propagative guided waves in the cavity. With a particular cavity length and a particular frequency, total reflection also happens for the two reflected waves at the opposite end of the cavity. In this way, the two coexisting standing waves underpin a trapped mode. It is found that the two standing waves are not two closed-cavity modes. Thus, this work presents a new understanding of such embedded trapped modes as a product of total reflection of two guided waves at the interface between two waveguides, rather than interference between two eigenmodes of a closed cavity. For quasi-trapped modes, the Fano scattering phenomenon owing to the effects of two acoustic channels is also shown.
