Linear instability mechanisms for sand wave formation

Natalia L. Komarova, Suzanne J.M.H. Hulscher

Research output: Contribution to journalArticleAcademicpeer-review

66 Citations (Scopus)


A height- and flow-dependent model for turbulent viscosity is employed to explain the generation of sand waves in tidal seas. This new model resolves the problem of excitation of very long waves in sand wave formation, because it leads to damping of the long waves and gives a finite separation between the most excited mode and the zero mode. For parameters within their physically realistic ranges, a linear analysis of the resulting system yields a first excited mode whose wavelength is similar to the characteristic wavelength of sand waves observed in nature. The physical mechanism of sand wave formation as predicted by the new model is explained in detail. The dispersion relation obtained can be the starting point for a weakly nonlinear analysis of the system.
Original languageUndefined
Pages (from-to)219-246
Number of pages28
JournalJournal of fluid mechanics
Issue number413
Publication statusPublished - 2000


  • IR-20469
  • METIS-124021

Cite this