Sediment Transport Demonstration Channel- Engineering Lab Training Systems

EXERCISES AND PRACTICAL POSSIBILITIES Some Practical Possibilities of the Unit: Flow over a mobile sand-bed (bedforms associated with increasing flow intensity and sediment transport rate) 1.-    Lower Regime (bedforms exhibed): - Plane- bed (no motion). - Ripples and dunes. - Washed-out dunes. -Ripples. -Dunes. 2.-    Upper Regime(bedforms exhibed): - Plane- bed (with motion). - Chutes and pools. - Anti- dunes. - Breaking anti-dunes. - Standing waves. Flow over fixed, gravel-bed 3.-    Although the channel can not transport gravel, this can be used to investigate flow resistance in gravel and polder- bed rivers. 4.-    We can calculate the flow resistance coeficients, using equations such as those of Bray, Limerinos, Hey, Lacey, Thompson and Campbell and Bathurst and the results compared to the actual values obtained by observation. Flow structures 5.-    We can examine the structure of turbulence in the flow, using dye injection, interesting for the dune bedform configuration and clearly demonstrates separation on the lee face. Fixed, smooth bed flow (the channel may be used without sediment on the bed to demonstrate several flow phenomena and equations) 6.-    Rapid, super- critical flow- dominance of intertial over gravity forces, shock waves from flow obstructions. 7.-    Turbulence. 8.-    Governing equations of open channel flow-Reynold’s number, Froude number, continuity, Bernoulli’s equation, weir equations. 9.-    Tranquil, sub-critical flow- movement of surface waves upstream against flow. 10.-Hydraulic jump- transition from super to sub critical flow, air entrainment, mixing. 11.-Flow measurement- using sharp crested weirs. Bedform hysteresis 12.-If the discharge in the channel changes quickly, there is no sufficient time for bedforms to adjust to the new flow regime. Hence, if a flood hydrograph is simulated by increasing and then decreasing the discharge, different depths will occur for the same discharge on the rising and falling limbs. Data collection and numerical evaluation(computational work) 13.-In addition to illustrating flow and sediment phenomena, we can use the channel for basic data collection and numerical evaluation of the following: - Flow resistance: Manning, Chezy and Darcy-Weisbach fricion factors for several bedform configuration.                                                                                                     Fluid Mechanics Lab Equipments manufacturers