The presented study examines various methods for phase averaging the naturally oscillating flowfield of a scaled-up fluidic oscillator. No external trigger is employed to control the oscillation of the flow. Mathematical and signal conditioning approaches for phase averaging the data are categorized and described. The results of these methods are evaluated for their accuracy in capturing the natural flowfield. The respective criteria are based on the minimum fluctuation in oscillation period length, the conservation of velocity amplitudes, and the number of snapshots per phase-averaging window. Although all methods produce reasonable qualitative results, only two methods are identified to provide the desired quantitative accuracy and suitability for the investigated flowfield. The first method is based on conditioning a time-resolved pressure signal from the feedback channels in the oscillator. An autocorrelation applied to the reference signal improves the period identification. The second method employs a mathematical approach by means of proper orthogonal decomposition. Because the conventional use of proper orthogonal decomposition reveals shortcomings in quantitative accuracy, it is modified by imposing an even distribution of snapshots per phase angle window. The results demonstrate the feasibility and improved accuracy of the modified proper orthogonal decomposition. Therefore, accurate phase averaging can be conducted without the need for a time-resolved reference signal.


    Access

    Access via TIB

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Phase-Averaging Methods for the Natural Flowfield of a Fluidic Oscillator



    Published in:

    Publication date :

    2015




    Type of media :

    Article (Journal)


    Type of material :

    Print


    Language :

    English



    Classification :

    BKL:    55.50 Luftfahrzeugtechnik / 55.60 Raumfahrttechnik / 55.60 / 50.93 / 55.50 / 50.93 Weltraumforschung
    Local classification TIB:    770/7040



    Phase-Averaging Methods for the Natural Flowfield of a Fluidic Oscillator

    Ostermann, Florian / Woszidlo, Rene / Nayeri, Christian N. et al. | AIAA | 2015


    Effects of Fluidic Oscillator Nozzle Angle on the Flowfield and Impingement Heat Transfer

    Hossain, Mohammad A. / Ameri, Ali / Gregory, James W. et al. | AIAA | 2021


    Phase-Synchronized Fluidic Oscillator Pair

    Tomac, Mehmet N. / Gregory, James W. | AIAA | 2018


    Phase-Synchronized Fluidic Oscillator Pair

    Tomac, Mehmet N. / Gregory, James W. | AIAA | 2017


    Fluidic Oscillator with Active Phase Control

    Nicholls, Chris J. / Bacic, Marko | AIAA | 2023