The effect of undulating leading-edge modifications on NACA 0021 airfoil characteristics

Nikan Rostamzadeh, Richard Kelso, bassam dally, Kristy Hansen

    Research output: Contribution to journalArticlepeer-review

    90 Citations (Scopus)


    In spite of its mammoth physical size, the humpback whale's manoeuvrability in hunting has captured the attention of biologists as well as fluid mechanists. It has now been established that the protrusions on the leading-edges of the humpback's pectoral flippers, known as tubercles, account for this species' agility and manoeuvrability. In the present work, Prandtl's nonlinear lifting-line theory was employed to propose a hypothesis that the favourable traits observed in the performance of tubercled lifting bodies are not exclusive to this form of leading-edge configuration. Accordingly, a novel alternative to tubercles was introduced and incorporated into the design of four airfoils that underwent wind tunnel force and pressure measurement tests in the transitional flow regime. In addition, a Computation Fluid Dynamics study was performed using the Shear Stress Transport transitional model in the context of unsteady Reynolds-Averaged Navier-Stokes at several attack angles. The results from the numerical investigation are in reasonable agreement with those of the experiments, and suggest the presence of features that are also observed in flows over tubercled foils, most notably a distinct pair of streamwise vortices for each wavelength of the tubercle-like feature.

    Original languageEnglish
    Article number117101
    Pages (from-to)Article: 117101
    Number of pages19
    JournalPhysics of Fluids
    Issue number11
    Publication statusPublished - 30 Aug 2013


    Dive into the research topics of 'The effect of undulating leading-edge modifications on NACA 0021 airfoil characteristics'. Together they form a unique fingerprint.

    Cite this