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The terminal settling velocity (TSV) of solid particles is experimentally determined in fluidizing columns. In monodispersed (single component) systems, the bed expansion behavior has been experimented with using pseudoplastic liquids. The terminal velocity is calculated from the plot of bed voidage (ε) vs. liquid velocity and extrapolating to ε = 1.0. An empirical correlation is developed for determining the TVS with acceptable statistical accuracy. Successful applicability of ANN modeling has been reported. After comparing with existing literature, it was found that the present work yielded better results (based on the statistical error parameters) than the previous literature.

The channel erosion downstream spillway dams in non-cohesive materials has been analyzed from the viewpoint of methods of similarity and dimension theory. The obtained criterion equation connects the maximum depth of the local erosion with its determining parameters: length of concrete lining of bed in the down water of the spillway dam; Froude number at the contracted cross section; Archimedes and Reynolds criterions; submergence factor of hydraulic jump. The problem may be formulated as follows: the geometric size of the structure, kinematics and dynamics of the flows in the model are similar to that in the prototype. Conditions under which the characteristic depth of the local erosion in the model would be recomputed into the prototype, like any geometric size, are being discussed.