Contact-line dynamics and damping for oscillating free surface flows
نویسندگان
چکیده
New experimental data on the frequency and damping of Faraday water waves in glass tanks are presented to demonstrate the contact-line effect on free surface flows. We find a complicated nonlinear relationship between wave frequency and amplitude near contact lines: The amplitude dispersion for decaying standing waves directly progresses from a nonlinear regime due to large amplitude to a regime due to contact-line nonlinearity. The relative damping rate is also a function of the wave amplitude, increasing significantly at smaller wave amplitude. These results are discussed in relation to different formulations of contact-line conditions for oscillatory motions and free surface flows. A new model is proposed to explain the observed amplitude scaling in the frequency and damping rate, and to relate these behaviors to slip-length and other contact-line measurements by Ting and Perlin @J. Fluid Mech. 295, 263 ~1995!#. © 2004 American Institute of Physics. @DOI: 10.1063/1.1644151#
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