[Mass Transport in Porous Sediments During a Turbulent Disturbance].

ABSTRACT

To examine mass transport in porous sediments during a turbulent flow, we established a simple sediment re-suspension device, made use of different sizes of sands as homogeneous sediments, and we injected 500 µg x cm(-3) soluble Rhodamine B into different parts of the sediment as the mass tracer, to observe mass transport during the turbulent condition. The research showed that in porous sediments, pore-water pressure difference would be generated because of the sediments' distinctive porosity and permeability, and further led to the convective flow and mass transport in porous media. Moreover, such mass transport was directly influenced by its burial depth and particle size of the sediment. While in homogeneous sediments, mass transport was strongly influenced in vertical direction under 200 r x min(-1) disturbance, and when moderately increased the size of porous particles under the same turbulent condition, such convection of pore-water would relatively enhance.