Angular Dynamics of a Small Particle in Turbulence.

Area of Science:

• Fluid dynamics
• Particle dynamics
• Turbulence

Background:

• Understanding particle behavior in unsteady flows is crucial for various applications.
• Existing models like Jeffery's equation often neglect inertial effects.

Purpose of the Study:

• To compute the angular dynamics of small, neutrally buoyant particles in unsteady fluids.
• To derive inertial corrections to Jeffery's equation.

Main Methods:

• Assumed small particle size and negligible translational slip.
• Treated unsteady and convective inertia as small perturbations.
• Derived an approximate torque on the particle.

Main Results:

• Developed an approximation for torque, yielding the first inertial corrections to Jeffery's equation.
• Identified local vortex stretching as the source of these inertial corrections.

Conclusions:

• Inertial corrections due to vortex stretching can be substantial in turbulent flows.
• These findings are particularly relevant for understanding particle behavior in turbulent environments.