On the growth (and suppression) of very short-scale disturbances in mixed forced-free convection boundary layers

J.P. Denier, P.W. Duck, Jian Li

    Research output: Contribution to journalArticle

    6 Citations (Scopus)

    Abstract

    The two-dimensional boundary-layer flow over a cooled/heated flat plate is investigated.A cooled plate (with a free-stream flow and wall temperature distributionwhich admit similarity solutions) is shown to support non-modal disturbances, whichgrow algebraically with distance downstream from the leading edge of the plate. Ina number of flow regimes, these modes have diminishingly small wavelength, whichmay be studied in detail using asymptotic analysis.Corresponding non-self-similar solutions are also investigated. It is found that thereare important regimes in which if the temperature of the plate varies (in such a wayas to break self-similarity), then standard numerical schemes exhibit a breakdown ata finite distance downstream. This breakdown is analysed, and shown to be relatedto very short-scale disturbance modes, which manifest themselves in the spontaneousformation of an essential singularity at a finite downstream location. We show howthese difficulties can be overcome by treating the problem in a quasi-elliptic manner,in particular by prescribing suitable downstream (in addition to upstream) boundaryconditions.
    Original languageEnglish
    Pages (from-to)147-170
    JournalJournal of Fluid Mechanics
    Volume526
    DOIs
    Publication statusPublished - 2005

    Fingerprint Dive into the research topics of 'On the growth (and suppression) of very short-scale disturbances in mixed forced-free convection boundary layers'. Together they form a unique fingerprint.

  • Cite this