Flow measurements in the wake of an adhering and oscillating droplet using laser-Doppler velocity profile sensor

Abstract The removal of droplets on surfaces by an (air-) flow is relevant, e.g., for cleaning processes or to prevent corrosion damage electronic devices. Still the condition droplet movement not fully understood. Droplets start move downstream at a critical velocity v crit . For increasing velocity, this process related strong oscillation droplet. This supposed be key mechanism onset in conjunction with field around We report measurements wake adhering means laser-Doppler profile sensor and hot wire anemometry. Thanks excellent spatial temporal resolution its capability measure bidirectional flows, backflow region can detected Therefore, it concluded that structure driving inside against channel direction found previous work. Analyzing frequency spectra was also oscillating; peaks are same range as contour oscillation. Based frequency, diameter Strouhal number calculated. almost constant investigated regime volumes between 0.015 0.03. assumed aeroelastic self-excitation effect may present eventually leads movement. Graphic abstract