Abstract of COCHLEA Project

Modern high-frequency high-power microwave sources are usually electrically and physically large and the study of the wave propagation inside them becomes a very demanding job. Such a device is the gyrotron, and its main parts, i.e., gun, cavity, beam tunnel and collector, are complex and their study is a challenging issue. Of course, there have been developed several semi-analytical methods and numerical codes to treat such structures, however, the required computation resources are extremely large. A numerical approach based on the FDTD method has been initiated and it can simulate any waveguide structure without any assumption and simplification. Up to now, many kinds of sources (modal and current distributions) have been implemented as excitations as well as different kind of materials (PEC and dielectric). The main output of the code includes field components in time and space. Of course, some post-processing procedures have been developed, such as field integration to calculate the stored energy and the S-parameters, as well as several other quantities, i.e., cut-off frequencies, wavelengths etc. Of course, further steps of the code development include the beam-wave interaction study. The field components calculation has already been parallelized using OpenMP, while other parts of the code as well as the post-processing procedures need further parallelization and optimization, which will expand its capabilities to model and simulate electrically large structures. Note that the FDTD scheme is based on the Yee [1] algorithm (an easily parallelized procedure), therefore the numerical codes based on it can be extensively parallelized. The aim of this project is to further parallelize the existing code using a hybrid OpenMP-MPI scheme, to reduce the total computational time and the required computing resources as well as to make the best possible use of Helios computer center.

[1] K.S.Yee, "Numerical Solution of Initial Boundary Value Problems involving Maxwell's Equations in Isotropic Media". IEEE Trans. Antennas Propag., vol 14(3), 302-307, (1966).