Simulation of Rayleigh-Taylor instability by Smoothed Particle Hydrodynamics: Advantages and limitations

AbstractSmoothed Particle Hydrodynamics (SPH) is a fully Lagrangian, particle-based technique for fluid-flow computations. The main advantage over Eulerian techniques is no requirement of the grid, therefore this is a natural approach to simulate multi-phase flows. The main purpose of this study is an overview and the critical analysis of the SPH variants to see their influence on the flow computations with many components (the historical way of improving the SPH approach). The comparison is performed using common validation (two- and three-dimensional) tests: the Rayleigh-Taylor instability, a square-droplet deformation and a bubble rising in water. The special attention will be given to compare different surface-tension models.

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Modeling of multi-phase flows and natural convection in a square cavity using an incompressible smoothed particle hydrodynamics

International Journal of Numerical Methods for Heat &amp Fluid Flow ◽

10.1108/hff-05-2014-0161 ◽

2015 ◽

Vol 25 (3) ◽

pp. 513-533 ◽

Cited By ~ 30

Author(s):

Abdelraheem Mahmoud Aly

Keyword(s):

Natural Convection ◽

Taylor Instability ◽

Three Dimensions ◽

Square Cavity ◽

Content Type ◽

Incompressible Sph ◽

Particle Hydrodynamics ◽

Smoothed Particle ◽

Rayleigh Taylor Instability ◽

Multi Phase

Purpose – Modeling of multi-phase flows for Rayleigh-Taylor instability and natural convection in a square cavity has been investigated using an incompressible smoothed particle hydrodynamics (ISPH) technique. In this technique, incompressibility is enforced by using SPH projection method and a stabilized incompressible SPH method by relaxing the density invariance condition is applied. The paper aims to discuss these issues. Design/methodology/approach – The Rayleigh-Taylor instability is introduced in two and three phases by using ISPH method. The author simulated natural convection in a square/cubic cavity using ISPH method in two and three dimensions. The solutions represented in temperature, vertical velocity and horizontal velocity have been studied with different values of Rayleigh number Ra parameter (103=Ra=105). In addition, characteristic based scheme in Finite Element Method is introduced for modeling the natural convection in a square cavity. Findings – The results for Rayleigh-Taylor instability and natural convection flow had been compared with the previous researches. Originality/value – Modeling of multi-phase flows for Rayleigh-Taylor instability and natural convection in a square cavity has been investigated using an ISPH technique. In ISPH method, incompressibility is enforced by using SPH projection method and a stabilized incompressible SPH method by relaxing the density invariance condition is introduced. The Rayleigh-Taylor instability is introduced in two and three phases by using ISPH method. The author simulated natural convection in a square/cubic cavity using ISPH method in two and three dimensions.

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