Viscous peeling of a nanosheet

Area of Science:

• Multiscale modeling
• Fluid dynamics
• Materials science

Background:

• Understanding the dynamics of multilayered graphene nanosheets is crucial for advanced material applications.
• Investigating fluid-structure interactions in nanoscale systems is essential for predicting material behavior.

Purpose of the Study:

• To study the dynamics of peeling fronts in multilayered graphene nanosheets immersed in water.
• To quantify viscous resistance and identify dissipative mechanisms during the peeling process.

Main Methods:

• Combined molecular dynamics (MD) and continuum simulations.
• Simulated peeling by lifting a graphene nanosheet edge at a controlled velocity.
• Computed pulling force and compared MD results with a 1D continuum model.

Main Results:

• Viscous dependence of force on velocity is negligible below a threshold.
• Hydrodynamics dominated by viscous resistance near crack opening above the threshold.
• Negligible lubrication forces due to significant hydrodynamic slip.
• Identified drag resistance and resistance to gap opening as key dissipative mechanisms.
• Graphene sheet shape remained largely independent of pulling velocity.

Conclusions:

• The peeling dynamics of graphene nanosheets in water exhibit complex hydrodynamic behaviors.
• Two distinct dissipative mechanisms govern the peeling process, influenced by velocity-dependent viscous resistance.
• Hydrodynamic slip plays a significant role in reducing lubrication forces.