RESUSPENSION OF PARTICLE BED BY ROUND VERTICAL JET

An experimental study was carried out to investigate the resuspension (fluidization) of a loosely held monodispersed particle bed by a momen tum jet, discharging from below. The work was motivated by its applica tions to limnological situations where the bottom sediments are suspen ded by a series of jets fed by a ground-water karstic system. Two diff erent flow regimes were identified, and the conditions under which the y occur were mapped on a regime diagram between the two important nond imensional variables, h(o)/d(p) and h(o)/ (M(o)(1/2)/w(s)), where h(o) is the height of the particle layer; w(s) is the particle-settling ve locity; and M(o) is the momentum flux of the jet. The maximum height o f rise of particles within the jet was also determined as a function o f these nondimensional variables. Comparisons of laboratory and field observational results were also made.