Suspension of large inertial particles in a turbulent swirling flow

We present experimental observations of the spatial distribution large inertial particles suspended in a turbulent swirling flow at high Reynolds number. The plastic are heavier than working fluid so that their dynamics results from competition between gravitation and agitation. Two suspension regimes observed. At low rotation rate confined near bottom for any size or density. rate, loosely confined: small nearly homogeneously distributed ones found top as if gravity was reversed. discuss these using minimal random walk model accounting particle inertia.