1988 Volume 14 Issue 1 Pages 123-126
A method is presented for calculating the drained liquid volume in gravitational drainage by applying an empirical correction, which takes into account the effects of liquid viscosity on film flow, to the author's prior equations for the dewatering of granular beds. It was shown that the dehydration rate of highly viscous Newtonian liquid is strongly affected by the existence of filmwise liquid flow when the modified capillary number is larger than 2.5.
The predicted results agreed well with the experimental results for packed beds of glass beads and calcium carbonate particles of diameter 1641875 μm, under conditions where the liquid viscosity ranges from 0.001 to 0.76 Pa · s.
