scholarly journals LATTICE BOLTZMANN PSEUDO-POTENTIAL MODELLING OF MULTIPHASE DROPLET PHENOMENA

Compiler ◽  
2020 ◽  
Vol 9 (2) ◽  
Author(s):  
Thomas Ken Darmastono ◽  
Bahrul Jalaali
Keyword(s):  
Lattice Boltzmann ◽  
Gravitational Force ◽  
Fundamental Problem ◽  
Reaction Force ◽  
Multiphase System ◽  
Droplet Behavior ◽  
Parametric Studies ◽  
Boltzmann Method ◽  
Pseudo Potential ◽  
Eotvos Number

The multiphase modeling of a droplet in a multiphase system is considered becoming a fundamental problem in fluid dynamics. A complex understanding of droplet behavior is critical to reveal a deeper insight into a more complex multiphase system. Droplet behavior studies are necessary to obtain a better understanding of solving multiphase problems in both the science and industrial aspect. The droplet behavior is characterized by a non-dimensional number such as the Eötvös number. In this study, numerical simulation was performed using the Lattice Boltzmann method. Parametric studies of Eötvös number was done. The parametric study of the Eo number is obtained using LBM. Based on the results obtained, it is concluded that the gravitational force influences the downwards rate of the droplet. Furthermore, the shape of the droplet during falling was depended on the Eo number as well. The higher Eo number means higher gravitational force, hence the velocity of the droplet is increasing as well as the reaction force of surface tension. This study is beneficial to give a deeper explanation of multiphase phenomena as well as contribute to the modeling of multiphase phenomena using an alternative numerical method of LBM.

scholarly journals Three-dimensional lattice Boltzmann method benchmarks between color-gradient and pseudo-potential immiscible multi-component models

2017 ◽  
Vol 28 (07) ◽  
pp. 1750085 ◽  
Author(s):  
Sébastien Leclaire ◽  
Andrea Parmigiani ◽  
Bastien Chopard ◽  
Jonas Latt
Keyword(s):  
Lattice Boltzmann ◽  
Three Dimensional ◽  
Lattice Boltzmann Model ◽  
Test Problems ◽  
Droplet Deformation ◽  
Color Gradient ◽  
Scientific Results ◽  
Boltzmann Method ◽  
Component Models ◽  
Pseudo Potential

In this paper, a lattice Boltzmann color-gradient method is compared with a multi-component pseudo-potential lattice Boltzmann model for two test problems: a droplet deformation in a shear flow and a rising bubble subject to buoyancy forces. With the help of these two problems, the behavior of the two models is compared in situations of competing viscous, capillary and gravity forces. It is found that both models are able to generate relevant scientific results. However, while the color-gradient model is more complex than the pseudo-potential approach, numerical experiments show that it is also more powerful and suffers fewer limitations.

Analysis of freezing process about falling droplet using the lattice Boltzmann method

2018 ◽  
Vol 28 (10) ◽  
pp. 2442-2462 ◽  
Author(s):  
Xin Zhao ◽  
Bo Dong ◽  
Weizhong Li
Keyword(s):  
Lattice Boltzmann Method ◽  
Lattice Boltzmann ◽  
Potential Model ◽  
Horizontal Velocity ◽  
Freezing Process ◽  
Droplet Deformation ◽  
Droplet Shape ◽  
Content Type ◽  
Boltzmann Method ◽  
Pseudo Potential

Purpose The freezing phenomenon of a falling droplet is a frequently encountered phenomenon in various applications, such as spray crystallization, hail formation and artificial snowmaking. Therefore, this paper aims to understand the freezing processes of a falling droplet without and with initial horizontal velocity in a cold space. Design/methodology/approach The freezing processes of a falling droplet were characterized using a modified enthalpy-based lattice Boltzmann method. Findings The temperature field, streamlines and freezing process of the falling droplet were investigated and analyzed. The lower part of the droplet was frozen earlier than the upper part. The freezing trend slowed down in the later stage of the freezing process. The droplet shape was related to the initial vertical velocity, nucleation temperature and initial horizontal velocity. Originality/value A modified enthalpy-based lattice Boltzmann method is proposed. In the model, the improved pseudo-potential model is used and the radiation is considered. This method was firstly used to simulate the freezing process of a falling droplet. By examining these freezing processes in detail, the freezing trend and the effect factors of droplet deformation and freezing time were obtained, respectively.

scholarly journals Simulations of Boiling Systems Using a Lattice Boltzmann Method

2013 ◽  
Vol 13 (3) ◽  
pp. 696-705 ◽  
Author(s):  
L. Biferale ◽  
P. Perlekar ◽  
M. Sbragaglia ◽  
F. Toschi
Keyword(s):  
Numerical Simulations ◽  
Lattice Boltzmann Method ◽  
Latent Heat ◽  
Lattice Boltzmann ◽  
Temperature Fluctuations ◽  
Convective Cell ◽  
Turbulent Convection ◽  
Multi Phase ◽  
Boltzmann Method ◽  
Pseudo Potential

AbstractWe report about a numerical algorithm based on the lattice Boltzmann method and its applications for simulations of turbulent convection in multi-phase flows. We discuss the issue of ’latent heat’ definition using a thermodynamically consistent pseudo-potential on the lattice. We present results of numerical simulations in 3D with and without boiling, showing the distribution of pressure, density and temperature fluctuations inside a convective cell.

Lattice Boltzmann Simulation of Nucleation

2003 ◽  
Author(s):  
Takeshi Seta ◽  
Kenichi Okui ◽  
Eisyun Takegoshi
Keyword(s):  
Lattice Boltzmann ◽  
Lattice Boltzmann Model ◽  
Two Phase Flows ◽  
Two Phase ◽  
Lattice Boltzmann Simulation ◽  
Expansion Procedure ◽  
Theoretical Predictions ◽  
Boltzmann Method ◽  
Boltzmann Model ◽  
Pseudo Potential

We propose a lattice Boltzmann model capable of simulating nucleation. This LBM modifies a pseudo-potential so that it recovers a full set of hydrodynamic equations for two-phase flows based on the van der Waals-Cahn-Hilliard free energy theory through the Chapman-Enskog expansion procedure. Numerical measurements of thermal conductivity and of surface tension agree well with theoretical predictions. Simulations of phase transition, nucleation, pool boiling are carried out. They demonstrate that the model is applicable to two-phase flows with thermal effects. Using finite difference Lattice Boltzmann method ensures numerical stability of the scheme.

POROUS SUBSTRATE EFFECTS ON THERMAL FLOWS THROUGH A REV-SCALE FINITE VOLUME LATTICE BOLTZMANN MODEL

2014 ◽  
Vol 25 (02) ◽  
pp. 1350086 ◽  
Author(s):  
AHAD ZARGHAMI ◽  
SILVIA DI FRANCESCO ◽  
CHIARA BISCARINI
Keyword(s):  
Porous Media ◽  
Finite Volume ◽  
Lattice Boltzmann ◽  
Fluid Flows ◽  
Lattice Boltzmann Model ◽  
Parametric Studies ◽  
Boltzmann Method ◽  
Thermal Lattice Boltzmann ◽  
Boltzmann Model ◽  
Thermal Flows

In this paper, fluid flows with enhanced heat transfer in porous channels are investigated through a stable finite volume (FV) formulation of the thermal lattice Boltzmann method (LBM). Temperature field is tracked through a double distribution function (DDF) model, while the porous media is modeled using Brinkman–Forchheimer assumptions. The method is tested against flows in channels partially filled with porous media and parametric studies are conducted to evaluate the effects of various parameters, highlighting their influence on the thermo-hydrodynamic behavior.

scholarly journals Lattice Boltzmann Simulation of Multiple Bubbles Motion under Gravity

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Deming Nie ◽  
Jianzhong Lin ◽  
Limin Qiu ◽  
Xiaobin Zhang
Keyword(s):  
Lattice Boltzmann ◽  
Two Dimensions ◽  
Bubble Coalescence ◽  
Lattice Boltzmann Simulation ◽  
Multiple Bubbles ◽  
Coalescence Pattern ◽  
Boltzmann Method ◽  
Initial Arrangement ◽  
Eotvos Number ◽  
Horizontal Arrangement

The motion of multiple bubbles under gravity in two dimensions is numerically studied through the lattice Boltzmann method for the Eotvos number ranging from 1 to 12. Two kinds of initial arrangement are taken into account: vertical and horizontal arrangement. In both cases the effects of Eotvos number on the bubble coalescence and rising velocity are investigated. For the vertical arrangement, it has been found that the coalescence pattern is similar. The first coalescence always takes place between the two uppermost bubbles. And the last coalescence always takes place between the coalesced bubble and the bottommost bubble. For four bubbles in a horizontal arrangement, the outermost bubbles travel into the wake of the middle bubbles in all cases, which allows the bubbles to coalesce. The coalescence pattern is more complex for the case of eight bubbles, which strongly depends on the Eotvos number.

Sign in / Sign up

Export Citation Format

Share Document