Discussion of 'Analysis of Dynamic Wave Model for Unsteady Flow in an Open Channel' by Maurizio Venutelli

摘要

In the original paper, the analytical expressions of phase and group speeds and wave amplitude have been derived by studying the linearized shallow-water equations (SWEs). The author's results, accounting for both channel (S_0) and friction (S_f) slopes, allow assessing convergence and accuracy of numerical schemes commonly used to compute clear-water flows in the complete turbulent regime, assuming a constant friction parameter η. However, the shallow-water model is employed in several contexts in which the friction parameter cannot be assumed as a constant; for instance, clear-water flows in regimes different from the complete turbulent one (Yen 2002), free surface flows of mud (Engelund and Wan 1984), power-law fluids (Pascal 2006; Pascal and D'Alessio 2007), and dense particulates (Forterre and Pouliquen 2003).