固液混相開水路流れの水理特性に関する研究 (3)

Abstract

Successive experimental investigations have partly disclosed a complex structure of flowwhich contains solid particles in suspension. Although some theoretical researches on themechanism of interaction between solid particles and fluid have been carried out, manyuncertain characteristics of flow suspending solid particles remains to be clarified. Thispaper deals mainly with the velocity and concentration distributions of free surface shearflow with suspended solid particles.Main results obtained by the experimental investigation are as follows; 1) When neutrallybouyant particles are suspended, the velocity of a flow over smooth bed is decreased uniformlythroughout the whole depth, therefore the friction factor increases. 2) In a flow withsuspended sand particles, the velocity of a flow over smooth bed is decreased especiallynear the bed, while, over rough bed, it is increased near the water surface. For both casesvelocity gradient becomes larger than that in clear water flow. 3) In a sediment-laden flowover rough bed, the degree of increase in velocity is remarkable when the suspended sandparticles are coarse. 4) The value of β defined by the ratio of the transfer coefficient forsediment to that for momentum is larger than unity, and it reduces for coaser sediment.