Roughness Effects of Subaquaeous Ripples and Dunes

Numerous questions and problems on Earth with respect to other planets arise from morphodynamic processes caused by sediment movements driven flows of fluids, such as water, air gases. A surface opposes the current a resistance that is determined its skin or grain roughness. As soon sand waves, ripples and/or dunes, are formed, these bedforms cause further flow, so-called form Dependent dimensions roughness can be much more pronounced than The relevant literature provides large number solution approaches based different basic ideas result quality. aim this paper comparative analysis literature. For purpose, 14 bedform-related friction in subaqueous case evaluated using 637 measurements laboratory natural settings. We found all were significantly accurate for dunes. Since was equally tested, it reasonable assume measurement inaccuracies dunes rather due themselves. approach Engelund 1977 proved most among investigated here. It Borda–Carnot formulation an additional empirical term. An analytical derivation justification provided