Numerical simulation of morphological changes in rivers and reservoirs

For the computation of the morphological changes in river or reservoir beds, due to erosion or deposition, a hydrodynamic model is combined with the sediment continuity equation. The hydrodynamic model is based upon the equations of mass and momentum conservation. For the solution of the above system of three partial differential equations, the explicit numerical schemes of MacCormack and Lax-Wendroff are tested. The whole mathematical model is applied to two experimental cases and to a real case. The first experimental case concerns the aggradation in a laboratory channel due to sediment overloading, and the second one the sediment release from a reservoir after a dam break. The real case concerns the morphological changes in the torrent Mallero (Northern Italy) during a flood event.