Related Experiment Video
Updated: Jun 2, 2026

Characterization of Anisotropic Leaky Mode Modulators for Holovideo
Published on: March 19, 2016
Mode propagation in curved waveguides and scattering by inhomogeneities: application to the elastodynamics of helical
1Institut Franýais des Sciences et Technologies des Transports, de l'Amýnagement et des Rýseaux, Centre de Nantes, BP4129, 44341 Bouguenais Cedex, France. fabien.treyssede@ifsttar.fr
Abstract:
This paper reports on an investigation into the propagation of guided modes in curved waveguides and their scattering by inhomogeneities. In a general framework, the existence of propagation modes traveling in curved waveguides is discussed. The concept of translational invariance, intuitively used for the analysis of straight waveguides, is highlighted for curvilinear coordinate systems. Provided that the cross-section shape and medium properties do not vary along the waveguide axis, it is shown that a sufficient condition for invariance is the independence on the axial coordinate of the metric tensor. Such a condition is indeed checked by helical coordinate systems. This study then focuses on the elastodynamics of helical waveguides. Given the difficulty in achieving analytical solutions, a purely numerical approach is chosen based on the so-called semi-analytical finite element method. This method allows the computation of eigenmodes propagating in infinite waveguides. For the investigation of modal scattering by inhomogeneities, a hybrid finite element method is developed for curved waveguides. The technique consists in applying modal expansions at cross-section boundaries of the finite element model, yielding transparent boundary conditions. The final part of this paper deals with scattering results obtained in free-end helical waveguides. Two validation tests are also performed.
Related Concept Videos
Propagation of Waves
Consider a scenario where a wave propagates from a string of low linear mass density to a string of high linear mass density. In such a case, the reflected wave is out of phase with respect to the incident wave, however the...
Deformations in a Transverse Cross Section
As the material stretches, it expands or contracts in orthogonal directions to the load. This phenomenon varies...
Propagation Speed of Electromagnetic Waves
Divergence and Curl
Divergence and Curl of Electric Field
Standing Waves in a Cavity
