Abstract
Modern gyrotron beam tunnels are rather complicated structures designed to enhance the suppression of the parasitic oscillations, which may be excited there. In some beam tunnel designs, azimuthal corrugations are engraved on their walls to further improve the suppression of these oscillations. In this work, we investigate the effect of the geometrical properties of the corrugations on the propagation characteristics of TE modes for the simplified model of a smooth waveguide with an azimuthally corrugated region. For this structure, the scattering parameters are calculated and the mode conversion is investigated with the in-house FDTD code COCHLEA.
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Acknowledgment
The authors would like to thank Prof. M. Q. Tran and Dr. I. Chelis for their valuable comments and advices. This work was carried out within the framework of the EUROfusion Consortium and received funding from the EURATOM research and training programme 2014–2018 and 2019–2020 under grant agreement no 633053. The numerical simulations were performed in the National HPC facility – ARIS – of Greek Research & Technology Network (GRNET) as well as in CINECA Marconi-Fusion. The contents of this paper are the sole responsibility of the authors and do not necessarily represent the views of the European Commission or its services or EUROfusion Consortium.
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Peponis, D.V., Latsas, G.P. & Tigelis, I.G. Investigation of Cylindrical Waveguides with Periodic Wedge-Shaped Azimuthal Corrugations Excited by TE Modes Using the FDTD Method. J Infrared Milli Terahz Waves 42, 761–771 (2021). https://doi.org/10.1007/s10762-021-00809-3
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DOI: https://doi.org/10.1007/s10762-021-00809-3