Modulating Incipient Entrainment of Coarse Particles: The Impact of Flow Turbulence

The incipient motion of coarse particles is a cornerstone of bed stability and sediment transport processes in turbulent flows, profoundly influencing riverbed morphodynamics and the resilience of hydraulic infrastructure. While traditional incipient motion criteria rely on steady-state shear stress thresholds, dynamic effects due to the inherent variability of flow turbulence remain poorly linked to the assessment of incipient particle entrainment in the lab or real-world field conditions.

This study aims to examine how alterations in flow conditions modulate the critical hydraulic thresholds for coarse particle entrainment under fully submerged, turbulent regimes. Leveraging instrumented particles integrated with inertial measurement units (IMUs) to capture real-time accelerations and angular velocities [1, 2], we dissect particle responses at the brink of motion. Derived flow--particle interaction metrics illuminate the mechanistic pathways, including torque generation and hydrodynamic lift, that govern entrainment [3, 4].

We hypothesize that flow turbulence can dramatically affect the energy imparted towards particle entrainment. These discoveries underscore the utility of IMU-derived metrics for predictive assessment of destabilization risks in dynamic river systems or scour-vulnerable channels.

References

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