The late stage of the free fall of homogeneous and heterogeneous cones in a quiescent water medium and the induced flow are experimentally inspected using three-dimensional particle tracking velocimetry and volumetric particle image velocimetry. The structures shared the same geometry but had different combined specific gravity SG[1.2,8]. Results showed four distinct free-fall patterns, which were modulated by the degree of heterogeneity and SG. They included (i) straight fall, (ii) regular sinusoidal-like trajectories with a maximum angle of oscillation with respect to the vertical, θmax<π/2, (iii) motions characterized by inclined translations and large rotations with θmax>π/2, and (iv) tumbling followed by an irregular motion. The straight fall occurred in cones with SG6 regardless of the mass distribution. The sinusoidal motions arose in the homogeneous cones with SG<3. The large rotations occurred with heterogeneous cones of SG<3, whereas the tumbling with irregular motions occurred in the heterogeneous cone with the highest ratio between the center of mass and geometrical centroid. Inspection of the linear and angular components of the velocities and accelerations reveal the distinct patterns and the linkage with the surrounding flow.
ASJC Scopus subject areas
- Computational Mechanics
- Modeling and Simulation
- Fluid Flow and Transfer Processes