| 摘 要： | The head loss along pipeline in hydrotransport has been studied through a set of well arranged experiments. For pseudo one-phase now with fully mixed sediment particles, a modified Reynolds number Re1 consisting of yield stress τB and rigidity η of the Bingham fluid and other hydraulic parameters is adopted, the relationship between Re1 and friction factor λ is the same as that of clear water. For two-phase flow when all particles are fully suspended, the head loss is the same as that of pseudo one-phase flow. If coarse particles move as bed load, extra resistance will occur. The critical condition under which the extra flow resistance appears has been found. Two types of theoretically deduced resistance curves agree well with the experimental results. It can be deduced that the pressure gradient is proportional to D-1 to D-1.25, depending on the rheological properties of suspension and the flow velocity. Drag reduction may take place only in two-phase flow with bed load movement. Adding fine particles weakens bed load movement, consequently, head loss reduces.
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