Critical flow solution to Gill's model of rotating channel hydraulics

R. Iiacono

Research output: Contribution to journalArticle


Gill's semigeostrophic equations of one-layer, rotating channel hydraulics are exactly solved at the critical section, for flows with a finite uniform potential vorticity (PV). A detailed characterization of the critical flow at the sill is consequently obtained, together with a simple, explicit expression for the associated mass transport, that provides a direct extension of the well-known transport formula of zero-PV theory. The dependence of the mass transport on the PV, for a given average flow energy, is found to be non-monotonic. In particular, the transport increases when the PV is raised from zero, attaining a maximum value that can be up to twice those predicted by the zero-PV theory. This suggests that, contrary to common belief, finite-PV effects may be important in determining the mass transport in real oceanic outflows. © 2006 Cambridge University Press.
Original languageEnglish
Pages (from-to)381 - 392
Number of pages12
JournalJournal of Fluid Mechanics
Publication statusPublished - Apr 2006
Externally publishedYes


All Science Journal Classification (ASJC) codes

  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

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