Near-Wall Cavitation Effect: A Molecular Dynamics Study

Area of Science:

• Fluid Dynamics
• Materials Science
• Computational Physics

Background:

• Cavitation is widely studied, yet its internal mechanism remains poorly understood.
• Understanding near-wall effects is crucial for controlling cavitation.

Purpose of the Study:

• To elucidate the microlevel mechanism of near-wall cavitation.
• To investigate the influence of wall wettability and temperature on cavitation dynamics.

Main Methods:

• Development of a microlevel near-wall model using LAMMPS.
• Molecular dynamics (MD) simulations to analyze liquid behavior under pressure changes.
• Evaluation of void volume fraction and density distribution.

Main Results:

• Cavitation progresses through distinct initial and rapid growth stages.
• Hydrophobic walls form a gas layer, reducing density fluctuations.
• Hydrophilic walls exhibit increased density fluctuations.
• Higher system temperatures promote molecular motion and intensify cavitation.

Conclusions:

• Near-wall cavitation dynamics are significantly influenced by surface wettability and temperature.
• MD simulations provide valuable insights into cavitation mechanisms.
• Findings offer a theoretical foundation for advanced cavitation studies.