Effects of Inclined Interface Angle on Compressible Rayleigh-Taylor Instability: A Numerical Study Based on the...

Area of Science:

• Fluid Dynamics
• Computational Physics
• Instability Phenomena

Background:

• Rayleigh-Taylor (RT) instability is a fundamental fluid phenomenon with broad natural and engineering relevance.
• Understanding the influence of initial interface geometry is crucial for predicting RT instability behavior.

Purpose of the Study:

• To investigate the effect of an initial inclined interface on compressible Rayleigh-Taylor instability.
• To analyze both thermodynamic non-equilibrium (TNE) and hydrodynamic non-equilibrium (HNE) effects.

Main Methods:

• Employed the two-component discrete Boltzmann method for simulation.
• Analyzed global average density gradients, non-organized energy fluxes, and non-equilibrium intensity over time.

Main Results:

• Horizontal density gradients and non-equilibrium intensity initially increase then decrease.
• Vertical density gradients exhibit a descend-rise-descend pattern.
• Increasing the initial interface angle amplifies density gradients and TNE intensity.

Conclusions:

• The initial interface angle is a critical parameter influencing compressible RT instability.
• Three competing mechanisms govern the evolution of non-equilibrium effects: interface elongation, viscosity, and fluid dissipation/penetration.