At transitional Reynolds numbers, an elastically supported airfoil oscillating in pitch can undergo laminar separation flutter (LSF), which is characterized by self-sustained small-amplitude oscillations. To gain insight into the mechanism of LSF, we conduct wind tunnel tests for 41,570 < Re < 83,140 to investigate the LSF response of a freely rotating NACA0015 airfoil with various structural natural frequencies and positions of the elastic axis. The experimental results show that the dominant mode of flow around the NACA0015 airfoil abruptly changes at Re = 68,600 , resulting in a change in the trend of LSF response. Then, an aeroelastic model is constructed to explain how the instability of LSF arises. This model can accurately predict the LSF frequency of airfoils with various structural natural frequencies. Moreover, based on the aeroelastic model, we perform linear stability analysis on the aeroelastic system and propose the instability criterion for LSF as ( C Mea / α ) | α = 0 < 0 . This instability criterion is identical to that for rotational galloping of square cylinder, indicating that LSF and rotational galloping of square cylinder are essentially the same aeroelastic phenomenon that appears in different aerodynamic profiles. This finding identifies the underlying cause for the remarkable similarities between the two phenomena.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    New Viewpoint on the Mechanism of Laminar Separation Flutter


    Contributors:
    Lyu, Zhen (author) / Lim, H. D. (author) / Zhang, Weiwei (author)

    Published in:

    AIAA Journal ; 61 , 7 ; 3032-3044


    Publication date :

    2023-05-18


    Size :

    13 pages




    Type of media :

    Article (Journal)


    Type of material :

    Electronic Resource


    Language :

    English




    Mitigation of Laminar Separation Flutter Using Plasma-Based Actuators

    Barnes, Caleb J. / Visbal, Miguel R. | AIAA | 2018



    A new viewpoint on the mechanism of transonic single-degree-of-freedom flutter

    Gao, Chuanqiang / Zhang, Weiwei / Ye, Zhengyin | Elsevier | 2016


    Risk Analysis for Flutter of Laminar Wings

    Tichy, Lorenz / Mai, Holger / Fehrs, Michael et al. | German Aerospace Center (DLR) | 2017

    Free access

    Study on Shock-Induced Panel Flutter in 2-D Laminar Flow

    Boyer, Nathan / McNamara, Jack J. / Gaitonde, Datta V. | AIAA | 2016