Heterogeneous Flow of Solids in Pipelines

The state of knowledge of predicting the head losses of heterogeneous flow of slurries in pipes has been reviewed. From published and unpublished papers and these, data for solid-liquid flow in pipes, encompassing a wide range of experimental variables, were collected (including 2,549 data points). This information was converted to a common set of units. For various reasons, 1,097 data points were discarded. Those remaining were used to investigate the validity of three leading equations of solid-liquid flow as prediction equations. A dimensionless number NI has been introduced, which permits quantitative differentiation of heterogeneous flow from saltation. It is recommended that this number be used in the same manner as the Reynolds number in single-phase flow. A set of two equations of Durand's type has been proposed for the prediction of head losses of the heterogeneous regime. The prediction by this set of new equations has been found to be quite accurate, and superior to all existing ones.