简介：Laboratoryexperimentsonlongitudinaldispersioninclear-waterandsediment-ladenopenchannelflowsarereported.Datafromtheseexperimentsandthoseavailablefrompreviousstudiesindicatethatthesuspendedsedimentpresentintheflowaffectsthelongitudinaldispersionprocess.Theobservedvelocitydistributionsoverthedepthofsediment-ladenflowsindicatethatthevelocitydeviatesfromthemeanvelocitymoreinsediment-ladenflowsthaninclear-waterflows.Thevelocitydistributionsoverthecrosssectionandsecondaryflowinthechannelarealsoexpectedtobealteredduetothepresenceofsuspendedsedimentsintheflow.Forthesereasons,moredispersionisfoundinsediment-ladenflowsthanincorrespondingclear-waterflows.Apredictorforthedispersioncoefficientinsediment-ladenflowsisproposed.