An approach for finding quantum leap of drag reduction: Based on the weakly-stochastic Navier-Stokes equation

Ken Naitoh, Tsuyoshi Nogami, Takahiro Tobe

    Research output: Chapter in Book/Report/Conference proceedingConference contribution

    Abstract

    While varying inlet disturbances, the transition points in space from laminar flow to turbulence in pipes and on airfoil in wind tunnel are here solved by using the weakly-stochastic Navier-Stokes equation and a finite difference method proposed by us, although the previous numerical simulations and instability theories based on the deterministic Navier-Stokes equation could not indicate the transition point in closed pipe flow. The most important point of our approach is a theoretical and philosophical method proposed for determining the stochasticity level, which is deeply related to boundary condition. Independence of the transition point on grid size implies that stochasticity is dominant rather than numerical discretization. Moreover, we qualitatively clarify the relation between the transition point and amount of adit on solid wall. Thus, the present approach will lead to a new way for reducing drag force.

    Original languageEnglish
    Title of host publication43rd Fluid Dynamics Conference
    Publication statusPublished - 2013
    Event43rd AIAA Fluid Dynamics Conference - San Diego, CA
    Duration: 2013 Jun 242013 Jun 27

    Other

    Other43rd AIAA Fluid Dynamics Conference
    CitySan Diego, CA
    Period13/6/2413/6/27

    Fingerprint

    Drag reduction
    Navier Stokes equations
    Pipe flow
    Laminar flow
    Airfoils
    Finite difference method
    Wind tunnels
    Drag
    Turbulence
    Pipe
    Boundary conditions
    Computer simulation

    ASJC Scopus subject areas

    • Fluid Flow and Transfer Processes
    • Energy Engineering and Power Technology
    • Aerospace Engineering
    • Mechanical Engineering

    Cite this

    An approach for finding quantum leap of drag reduction : Based on the weakly-stochastic Navier-Stokes equation. / Naitoh, Ken; Nogami, Tsuyoshi; Tobe, Takahiro.

    43rd Fluid Dynamics Conference. 2013.

    Research output: Chapter in Book/Report/Conference proceedingConference contribution

    Naitoh, K, Nogami, T & Tobe, T 2013, An approach for finding quantum leap of drag reduction: Based on the weakly-stochastic Navier-Stokes equation. in 43rd Fluid Dynamics Conference. 43rd AIAA Fluid Dynamics Conference, San Diego, CA, 13/6/24.
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    AU - Tobe, Takahiro

    PY - 2013

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