Christopher Sittl, M.Sc.

External PhD

Application of the matrix-Padé-via-Lanczos Method

In the acoustic optimization of automotive powertrains, it is not only meaningful, to reduce the physical quantities like the sound pressure level. It is also important to generate a noise, which is pleasant for the customers. Therefore, the evaluation of the systems transfer function as a common method, can be considered. To provide such a transfer function over a discretized field, the finite element method is an approach, for tackling the acoustic optimization just in the early phase of the product development.

The efficient solving of large linear systems arising from finite element discretization of acoustic scattering tasks is an undertaking for physicists and engineers. Following the simple approach of solving the matrix system with a direct or iterative solver at each frequency can be prohibitively expensive, depending on the system size and the needed frequency resolution. A workaround to this straight forward approach could be the matrix-Padé-via-Lanczos method, which provides a Padé-approximation of the systems frequency response. So for the result is not specific for one frequency as with the approach by solving the linear system for each frequency but rather for a frequency range around an expansion frequency.

Project Partners

  • Technical University of Munich
  • Ostbayerische Technische Hochschule Regensburg
  • Otto von Guericke University of Magdeburg
  • CHP Messtechnik GmbH



  • Sittl, Christopher; Marburg, Steffen; Wagner, Marcus: Application of a Krylov subspace method for an efficient solution of acoustic transfer functions. Mechanical Systems and Signal Processing 148, 2021, 107135 more… BibTeX Full text ( DOI )