Domain decomposition eigenvalue solver for finite element mode computation in air-inlet

The method which has been developed solves the Maxwell equations in cylindrical waveguides of any plane shape without internal conducting media. Parallel implementation for 2D electromagnetic mode computation on a distributed memory machine is described. The most expensive task of this problem consists of seeking the smallest eigenvalues (and the associated eigenvectors) of large, sparse and real matrices coming from the finite element discretization. A parallel method is introduced based on Lanczos, QR and iterative inverse power algorithms, but also on a domain-decomposition solver for large and sparse linear systems. The computational times on IPSC860, PARAGON and CRAY-YMP computers are presented.