Tumbling dynamics of inertial inextensible chains in extensional flow

Area of Science:

• Polymer physics
• Fluid dynamics
• Computational biophysics

Background:

• Traditional models often assume overdamped dynamics for elongated chains.
• Understanding inertial effects is crucial for accurate simulations of polymer behavior in flow.

Purpose of the Study:

• To investigate the influence of inertia on the dynamics of elongated chains.
• To characterize the coil-stretch transition and tumbling instability beyond the overdamped regime.

Main Methods:

• Numerical simulations of freely jointed bead-rod chains.
• Analysis of chain motion in extensional flow with thermal noise.

Main Results:

• The coil-stretch transition persists in the presence of inertia.
• Transition dynamics exhibit a nonlinear dependence on Péclet and Stokes numbers.
• Intermediate stable configurations play a role, trapping chains during tumbling.

Conclusions:

• Inertia must be considered for realistic modeling of elongated chain dynamics.
• The interplay between inertia, flow, and chain length dictates complex behaviors.
• Stable intermediate configurations influence chain evolution in flow.