Evaluation of Unsteady Wall Shear Stress by Zielke's Method

Alan E. Vardy, Jim M.B. Brown

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    12 Citations (Scopus)


    The method used in the classical paper by Zielke to estimate the unsteady component of shear stress in unsteady pipe flows is revisited. It is found that the method is undesirably sensitive to the size of the integration time step. The sensitivity is shown to be caused dominantly by the first term in the integration when inadequate allowance is made for the infinite value of the weighting function. A simple method of avoiding the error without requiring the use of small grid sizes is presented.

    Original languageEnglish
    Pages (from-to)453-456
    Number of pages4
    JournalJournal of Hydraulic Engineering
    Issue number7
    Publication statusPublished - Jul 2010

    Research Output

    • 12 Citations
    • 1 Comment/debate

    Closure to "Evaluation of unsteady wall shear stress by Zielke's method" by Alan E. Vardy and Jim M. B. Brown

    Vardy, A. E. & Brown, J. M. B., May 2013, In : Journal of Hydraulic Engineering. 139, 5, p. 565-566 2 p.

    Research output: Contribution to journalComment/debate

    1 Citation (Scopus)

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