Ablative Rayleigh–Taylor instability in the limit of an infinitely large density ratio

2005 ◽  
Vol 333 (5) ◽  
pp. 379-388 ◽  
Author(s):  
Paul Clavin ◽  
Christophe Almarcha
Keyword(s):  
Density Ratio ◽  
Taylor Instability ◽  
Large Density ◽  
Large Density Ratio ◽  
Rayleigh Taylor Instability

Numerical Simulation of Rayleigh-Taylor Instability with Large Density Ratios Based on RKDG Method

2013 ◽  
Vol 423-426 ◽  
pp. 1751-1756 ◽  
Author(s):  
Jun Wu Tian ◽  
Xiang Jiang Yuan
Keyword(s):  
Body Force ◽  
Contact Discontinuity ◽  
Density Ratio ◽  
Taylor Instability ◽  
Interface Capturing ◽  
Instability Problem ◽  
Large Density ◽  
Large Density Ratio ◽  
Rayleigh Taylor Instability ◽  
Density Ratios

Rayleigh-Taylor instability problem with large density ratios is simulated by RKDG method which is developed for Euler equations with an additional body force corresponding to the gravity. The interface capturing ability of RKDG method is testified, while the density ratio (heavy to light) ranges from 3 to 20. Numerical results show that RKDG method has capability to pursue contact discontinuity in Rayleigh-Taylor instability with large density ratio. In the late stage of Rayleigh-Taylor instability problem, the contact line begins to crash, but the numerical solution is still smooth near the interface and has high resolution.

NUMERICAL SIMULATION OF RAYLEIGH–TAYLOR INSTABILITY BASED ON AN IMPROVED PARTICLE LEVEL SET METHOD

2014 ◽  
Vol 11 (04) ◽  
pp. 1350094 ◽  
Author(s):  
HUI TIAN ◽  
GUOJUN LI ◽  
XIONGWEN ZHANG
Keyword(s):  
Level Set Method ◽  
Level Set ◽  
Stokes Equations ◽  
Density Ratio ◽  
Immiscible Fluids ◽  
Taylor Instability ◽  
Wide Range ◽  
Particle Level ◽  
Rayleigh Taylor Instability ◽  
Particle Level Set Method

An improved particle correction procedure for particle level set method is proposed and applied to the simulation of Rayleigh–Taylor instability (RTI) of the incompressible two-phase immiscible fluids. In the proposed method, an improved particle correction method is developed to deal with all the relative positions between escaped particles and cell corners, which can reduce the disturbance arising in the distance function correction process due to the non-normal direction movement of escaped particles. The improved method is validated through accurately capturing the moving interface of the Zalesak's disk. Furthermore, coupled with the projection method for solving the Navier–Stokes equations, the time-dependent evolution of the RTI interface over a wide range of Reynolds numbers, Atwood numbers and Weber numbers are numerically investigated. A good agreement between the present results and the existing analytical solutions is obtained and the accuracy of the proposed method is further verified. Moreover, the effects of control parameters including viscosity, density ratio, and surface tension coefficient on the evolution of RTI are analyzed in detail, and a critical Weber number for the development of RTI is found.

A Preconditioned Implicit Free-Surface Capture Scheme for Large Density Ratio on Tetrahedral Grids

2012 ◽  
Vol 11 (1) ◽  
pp. 215-248 ◽  
Author(s):  
Xin Lv ◽  
Qingping Zou ◽  
D.E. Reeve ◽  
Yong Zhao
Keyword(s):  
Free Surface ◽  
Density Ratio ◽  
Three Dimensional ◽  
Integration Scheme ◽  
Two Phase ◽  
Fully Implicit ◽  
Large Density ◽  
Multi Stage ◽  
Tetrahedral Grids ◽  
Large Density Ratio

AbstractWe present a three dimensional preconditioned implicit free-surface capture scheme on tetrahedral grids. The current scheme improves our recently reported method [10] in several aspects. Specifically, we modified the original eigensystem by applying a preconditioning matrix so that the new eigensystem is virtually independent of density ratio, which is typically large for practical two-phase problems. Further, we replaced the explicit multi-stage Runge-Kutta method by a fully implicit Euler integration scheme for the Navier-Stokes (NS) solver and the Volume of Fluids (VOF) equation is now solved with a second order Crank-Nicolson implicit scheme to reduce the numerical diffusion effect. The preconditioned restarted Generalized Minimal RESidual method (GMRES) is then employed to solve the resulting linear system. The validation studies show that with these modifications, the method has improved stability and accuracy when dealing with large density ratio two-phase problems.

LBM Application in Two-Phase Fluid Flow with Large Density Ratio

2012 ◽  
Vol 476-478 ◽  
pp. 871-875
Author(s):  
Qing Ming Chang ◽  
Yin Kai Yang ◽  
Jing Yuan ◽  
Xia Chen ◽  
Min Zhang
Keyword(s):  
Gravity Wave ◽  
Numerical Solutions ◽  
Density Ratio ◽  
Surface Tension Force ◽  
Analytic Solutions ◽  
Lattice Boltzmann Model ◽  
Two Phase ◽  
Large Density ◽  
Large Density Ratio ◽  
Parasitic Currents

In this paper, a stable lattice Boltzmann model (LBM) based on non-ideal gases is presented for simulation of incompressible two-phase flows with large density ratio. To reduce the parasitic currents across the interface and correspondingly increase the numerical stability, the stress and potential forms of the surface tension force is employed. The applications to a stationary bubble and capillary-gravity wave with density ratio 1000 are given to verify this model. The numerical solutions is agree well with analytic solutions of the Laplace's law and capillary-gravity wave.

Sign in / Sign up

Export Citation Format

Share Document