A random-walk study of scalar mixing in water waves.

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Xuefei Wu, Dongfang Liang

Monday 29 june 2015

17:54 - 17:57h at Europe 1 & 2 (level 0)

Themes: (T) Hydro-environment, (ST) Ecohydraulics and ecohydrology, Poster pitches

Parallel session: Poster pitch: 3G. Environment - Ecohydraulic

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This paper applies the random walk method to study the scalar transport phenomena in vertical two-dimensional wave flows. This Lagrangian model is first verified against an idealized problem involving unsteady shear flows, and the good agreement between the simulated dispersion coefficient and the analytical value demonstrates the validity of this model. Water waves are then formulated based on the linear and second order Stokes wave theories. The longitudinal dispersion coefficients are calculated and compared between the two wave theories. The simulation results show high accuracy of the random walk method. The choice of the control parameters used in the model, such as the particle number and time step, is discussed for a good balance between the computational expense and accuracy.