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Physically Insignificant Fast Waves

  • Dale R. Durran
Part of the Texts in Applied Mathematics book series (TAM, volume 32)

Abstract

One reason that explicit time-differencing is widely used in the simulation of wave-like flows is that accuracy considerations and stability constraints often yield similar criteria for the maximum time step in numerical integrations of systems that support a single type of wave motion. Many fluid systems, however, support more than one type of wave motion, and in such circumstances accuracy considerations and stability constraints can yield very different criteria for the maximum time step. If explicit time-differencing is used to construct a straightforward numerical approximation to the equations governing a system that supports several types of waves, the maximum stable time step will be limited by the Courant number associated with the most rapidly propagating wave, yet that rapidly propagating wave may be of little physical significance.

Keywords

Gravity Wave Sound Wave Rossby Wave Phase Speed Lamb Wave 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© Springer Science+Business Media New York 1999

Authors and Affiliations

  • Dale R. Durran
    • 1
  1. 1.Atmospheric SciencesUniversity of WashingtonSeattleUSA

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