Multiphase mesh-free particle modeling of local sediment scouring with μ(I) rheology

Abstract Sediment scouring is a common example of highly dynamic sediment transport. Considering its complexities, the accurate prediction of such a highly dynamic multiphase granular flow system is a challenge for the traditional numerical techniques that rely on a mesh system. The mesh-free particle methods are a newer generation of numerical techniques with an inherent ability to deal with the deformations and fragmentations of a multiphase continuum. This study aims at developing and evaluating a multiphase mesh-free particle model based on the weakly compressible moving particle semi-implicit (WC-MPS) formulation for simulation of sediment scouring. The sediment material is considered as a non-Newtonian viscoplastic fluid, whose behavior is predicted using a regularized μ(I) rheological model in combination with pressure-dependent yield criteria. The model is first validated for a benchmark problem of viscoplastic Poiseuille flow. It is then applied and evaluated for the study of two classical sediment scouring cases. The results show that the high-velocity flow currents and the circulations can create a low-viscosity region on the surface of the sediment continuum. Comparing the numerical results with the experimental measurements shows a good accuracy in prediction of the sediment profile, especially the shape and dimensions of the scour hole.

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Optimization of Moving Particle Semi-Implicit (MPS) Method and Studying of Flow Instability

Volume 8: Computational Fluid Dynamics (CFD); Nuclear Education and Public Acceptance ◽

10.1115/icone26-81948 ◽

2018 ◽

Author(s):

Kailun Guo ◽

Ronghua Chen ◽

Suizheng Qiu ◽

Wenxi Tian ◽

Guanghui Su ◽

...

Keyword(s):

Multiphase Flows ◽

Flow Instability ◽

Free Particle ◽

Particle Method ◽

Severe Accident ◽

Particle Methods ◽

Two Phase ◽

Mps Method ◽

Viscosity Term ◽

Moving Particle

Multiphase flow widely exists in the nature and engineering. The two-phase flow is the highlight of the studies about the flow in the vessel and steam explosion in nuclear severe accidents. The Moving Particle Semi-implicit (MPS) method is a fully-Lagrangian particle method without grid mesh which focuses on tracking the single particle and concerns with its movement. It has advantages in tracking complex multiphase flows compared with gird methods, and thus shows great potential in predicting multiphase flows. The objective of this thesis is to develop a general multiphase particle method based on the original MPS method and thus this work is of great significance for improving the numerical method for simulating the instability in reactor severe accident and two-phase flows in vessel. This research is intended to provide a study of the instability based on the MPS method. Latest achievements of mesh-free particle methods in instability are researched and a new multiphase MPS method, which is based on the original one, for simulating instability has been developed and validated. Based on referring to other researchers’ papers, the Pressure Poisson Equation (PPE), the viscosity term, the free surface particle determination part and the surface tension model are optimized or added. The numerical simulation on stratification behavior of two immiscible flows is carried out and results are analyzed after data processing. It is proved that the improved MPS method is more accurate than the original method in analysis of multiphase flows. In this paper, the main purposes are simulating and discussing Rayleigh-Taylor (R-T) instability and Kelvin-Helmholtz (K-H) instability. R-T and K-H instability play an important role in the mixing process of many layered flows. R-T instability occurs when a lower density fluid is supported by another density higher fluid or higher density fluid is accelerated by lower density fluid, and the resulting small perturbation increases and eventually forms turbulence. K-H instability is a small disturbance for two different densities, such as waves, at the interface of the two-phase fluid after giving a fixed acceleration in the fluid. Turbulence generated by R-T instability and K-H instability has an important effect in applications such as astrophysics, geophysics, and nuclear science.

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Recent Progress on Mesh-free Particle Methods for Simulations of Multi-phase Flows: A Review

KONA Powder and Particle Journal ◽

10.14356/kona.2020017 ◽

2020 ◽

Vol 37 (0) ◽

pp. 132-144 ◽

Cited By ~ 5

Author(s):

Mikio Sakai ◽

Yuki Mori ◽

Xiaosong Sun ◽

Kazuya Takabatake

Keyword(s):

Recent Progress ◽

Free Particle ◽

Particle Methods ◽

Mesh Free ◽

Multi Phase

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Numerical Simulation of Free Surface Flows by Using Weakly Compressible Corrected MPS Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.842.449 ◽

2013 ◽

Vol 842 ◽

pp. 449-454

Author(s):

Hao Wang ◽

Qin Jiang ◽

Chang Kuan Zhang

Keyword(s):

Experimental Data ◽

Free Surface ◽

Numerical Model ◽

Surface Deformation ◽

Free Particle ◽

Free Surface Flows ◽

Dam Break ◽

Mps Method ◽

Mesh Free ◽

Weakly Compressible

Mesh-free particle (Lagrangian) methods such as Moving Particle Semi-Implicit (MPS) are the latest generation of methods in the field of computational fluid dynamics where large interfacial deformations and fragmentations exist. Due to their mesh-free nature, these methods are capable of simulating any kind of boundary/interface deformation and fragmentations. In this study the weakly compressible corrected MPS (WCC-MPS) method is used to simulate dam break over a dry bed, which is a highly erosive and transient flow problem. The developed numerical model is first validated using a dry bed dam break problem by comparing with experimental data. Comparisons between the model results and experimental data showed that the developed numerical model with WCC-MPS method can well represent the dam break problems with very large free surface deformation and fragmentations.

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A NUMERICALLY CONSISTENT MULTIPHASE POISEUILLE FLOW COMPUTATION BY A NEW PARTICLE METHOD

Jurnal Teknologi ◽

10.11113/jt.v76.5629 ◽

2015 ◽

Vol 76 (8) ◽

Cited By ~ 1

Author(s):

K. C. Ng ◽

Y. H. Hwang ◽

T. W. H. Sheu ◽

M. Z. Yusoff

Keyword(s):

Fluid Flow ◽

Poiseuille Flow ◽

Particle Method ◽

Numerical Approach ◽

Particle Methods ◽

Diffusion Term ◽

Flow Solver ◽

Mesh Free ◽

Consistent Method ◽

Moving Particle

Recently, there is a rising interest in simulating fluid flow by using particle methods, which are mesh-free. However, the viscous stresses (or diffusion term) appeared in fluid flow governing equations are commonly expressed as the second-order derivatives of flow velocities, which are usually discretized by an inconsistent numerical approach in a particle-based method. In this work, a consistent method in discretizing the diffusion term is implemented in our particle-based fluid flow solver (namely the Moving Particle Pressure Mesh (MPPM) method). The new solver is then used to solve a multiphase Poiseuille flow problem. The error is decreasing while the grid is refined, showing the consistency of our current numerical implementation.

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MR-WC-MPS: A Multi-Resolution WC-MPS Method for Simulation of Free-Surface Flows

Water ◽

10.3390/w11071349 ◽

2019 ◽

Vol 11 (7) ◽

pp. 1349 ◽

Cited By ~ 1

Author(s):

Mohammad Amin Nabian ◽

Leila Farhadi

Keyword(s):

Free Surface ◽

Free Surface Flows ◽

Submarine Landslide ◽

Particle Methods ◽

Computational Time ◽

Computational Domain ◽

Surface Flows ◽

Mps Method ◽

Weakly Compressible ◽

Moving Particle

A Multi-Resolution Weakly Compressible Moving-Particle Semi-Implicit (MR-WC-MPS) method is presented in this paper for simulation of free-surface flows. To reduce the computational costs, as with the multi-grid schemes used in mesh-based methods, there is also a need in particle methods to efficiently capture the characteristics of different flow regions with different levels of complexity in different spatial resolutions. The proposed MR-WC-MPS method allows the use of particles with different sizes in a computational domain, analogous to multi-resolution grid in grid-based methods. To evaluate the accuracy and efficiency of the proposed method, it is applied to the dam-break and submarine landslide tests. It is shown that the MR-WC-MPS results, while about 15% faster, are in good agreement with the conventional single-resolution MPS results and experimental results. The remarkable ability of the MR-WC-MPS method in providing robust savings in computational time for up to 60% is then shown by applying the method for simulation of extended submarine landslide test.

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Implementation of three-dimensional physical reflective boundary conditions in mesh-free particle methods for continuum fluid dynamics: Validation tests and case studies

Physics of Fluids ◽

10.1063/1.5115776 ◽

2019 ◽

Vol 31 (10) ◽

pp. 103606 ◽

Cited By ~ 1

Author(s):

Carlos Alberto Dutra Fraga Filho ◽

Chong Peng ◽

Md Rushdie Ibne Islam ◽

Christopher McCabe ◽

Samiullah Baig ◽

...

Keyword(s):

Fluid Dynamics ◽

Boundary Conditions ◽

Case Studies ◽

Free Particle ◽

Three Dimensional ◽

Particle Methods ◽

Mesh Free ◽

Validation Tests

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Numerical Simulation of Behavior of Sand Particles during High-Speed Penetration with Particle Method

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.715.198 ◽

2016 ◽

Vol 715 ◽

pp. 198-202

Author(s):

Ryota Shimono ◽

Keiko Watanabe

Keyword(s):

Numerical Simulation ◽

High Speed ◽

Free Particle ◽

Particle Method ◽

Particle Methods ◽

Sand Particle ◽

Mesh Free ◽

Research Themes ◽

Macro Scale ◽

Sand Particles

The phenomena that occur during high-speed penetration of a projectile into sand particles are interesting subjects in engineering. The macro-scale research themes are the behavior of the ejected sand particles and the progress of the high-speed projectile, while the micro-scale research themes are the deformation and fragmentation of a single sand particle. Studies of these unique phenomena were conducted using both experiments and numerical simulation. Although accurate simulation of the behavior of sand particles during high-speed penetration is difficult because sand particles have characteristics of both fluids and solids, the reproducibility of the actual phenomena has improved in recent years with the development of particle methods. In our research, we conducted simulations of the phenomena using Smoothed Particle Hydrodynamics (SPH), which is a mesh-free, particle-based method. The results showed the possibility of accurate reproduction during high-speed projectile penetration into sand particles at the macro-scale.

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