Estimates of the mean ϵs and oscillatory ϵ′ strain rate as a function of the ethanol droplet displacement x/λs, at forcing frequencies (a) 332 Hz, (b) 586 Hz, and (c) 898 Hz. Depending on the acoustic forcing conditions (frequency and amplitude), the burning fuel droplet is characterized by weakly oscillating flame behavior (○), oscillatory flame motion (•) or periodic partial extinction and reignition (x).