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Article

Min Wang, Y.T. Feng, Ting T. Zhao and Yong Wang

Sand production is a challenging issue during hydrocarbon production in the oil and gas industry. This paper aims to investigate one sand production process, i.e…

Abstract

Purpose

Sand production is a challenging issue during hydrocarbon production in the oil and gas industry. This paper aims to investigate one sand production process, i.e. transient sand production, using a novel bonded particle lattice Boltzmann method. This mesoscopic technique provides a unique insight into complicated sand erosion process during oil exploitation.

Design/methodology/approach

The mesoscopic fluid-particle coupling is directly approached by the immersed moving boundary method in the framework of lattice Boltzmann method. Bonded particle method is used for resolving the deformation of solid. The onset of grain erosion of rocks, which are modelled by a bonded particle model, is realised by breaking the bonds simulating cementation when the tension or tangential force exceeds critical values.

Findings

It is proved that the complex fluid–solid interaction occurring at the pore/grain level can be well captured by the immersed moving boundary scheme in the framework of the lattice Boltzmann method. It is found that when the drawdown happens at the wellbore cavity, the tensile failure area appears at the edge of the cavity. Then, the tensile failure area gradually propagates inward, and the solid particles at the tensile failure area become fluidised because of large drag forces. Subsequently, some eroded particles are washed out. This numerical investigation is demonstrated through comparison with the experimental results. In addition, through breaking the cementation, which is simulated by bond models, between bonded particles, the transient particle erosion process is successfully captured.

Originality/value

A novel bonded particle lattice Boltzmann method is used to investigate the sand production problem at the grain level. It is proved that the complex fluid–solid interaction occurring at the pore/grain level can be well captured by the immersed moving boundary scheme in the framework of the lattice Boltzmann method. Through breaking the cementation, which is simulated by bond models, between bonded particles, the transient particle erosion process is successfully captured.

Details

Engineering Computations, vol. 36 no. 2
Type: Research Article
ISSN: 0264-4401

Keywords

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Article

Qingang Xiong, Arash Khosravi, Narjes Nabipour, Mohammad Hossein Doranehgard, Aida Sabaghmoghadam and David Ross

This paper aims to numerically investigate the nanofluid flow, heat transfer and entropy generation during natural convection in an annulus.

Abstract

Purpose

This paper aims to numerically investigate the nanofluid flow, heat transfer and entropy generation during natural convection in an annulus.

Design/methodology/approach

The lattice Boltzmann method is used to simulate the velocity and temperature fields. Furthermore, some special modifications are applied to make the lattice Boltzmann method capable for simulation in the curved boundary conditions. The annulus is filled with CuO-water nanofluid. The dynamic viscosity of nanofluid is estimated using KLL (Koo-Kleinstreuer-Li) model, and the nanoparticle shape effect is taken account in calculating the thermal conductivity. On the other hand, the local/volumetric entropy generation is used to show the irreversibility under influence of different parameters.

Findings

The effect of considered governing parameters including Rayleigh number (103<Ra < 106); nanoparticle concentration (0<<0.04) and configuration of annulus on the flow structure; temperature field; and local and total entropy generation and heat transfer rate are presented.

Originality/value

The originality of this work is using of lattice Boltzmann method is simulation of natural convection in a curved configuration and using of Koo–Kleinstreuer–Li correlation for simulation of nanofluid.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 12
Type: Research Article
ISSN: 0961-5539

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Article

Oluyinka O. Bamiro and William W. Liou

The purpose of the current paper is to develop a numerical methodology, based on the immersed boundary-lattice Boltzmann computational framework, for the Neumann and…

Abstract

Purpose

The purpose of the current paper is to develop a numerical methodology, based on the immersed boundary-lattice Boltzmann computational framework, for the Neumann and Dirichlet boundary conditions in problems involving natural and forced convection heat transfer.

Design/methodology/approach

The direct forcing immersed boundary method is extended to study the heat transfer by incompressible flow within the thermal lattice Boltzmann method (LBM) computational framework. The direct forcing and heating immersed boundary-LBM introduces a heat source term to the thermal LBM to account for the heat transfer occurring at the immersed boundary. New numerical treatments for the Neumann type of boundary condition and for the calculation of the local Nusselt number are developed. The developed methodologies have been applied to flows around immersed bodies with natural and forced convection, including steady as well as unsteady flows.

Findings

Numerical experiments involving immersed bodies in natural and forced convection have been performed in order to assess the validity of the direct heating IB-LBM. The flow cases studied also include steady and transient flow phenomena. Flow velocity field and isotherms have been used for qualitative comparisons with existing, published results. The surface averaged Nusselt number, Strouhal number, and lift coefficient (for the unsteady flow cases) have been used for quantitative comparison with published results. The results show that there are satisfactory agreements, qualitatively and quantitatively, between the results obtained by using the present method and those previously published.

Originality/value

Limited application of immersed boundary to thermal flows within the LBM has been studied by researchers; the few past studies were limited to Dirichlet boundary conditions and/or using of feedback forcing and heating approaches. In the current paper, the direct forcing and heating approach was used which helps to eliminate the arbitrary constants used in the feedback approaches. The developed new numerical treatments for the Neumann type of boundary condition and for the calculation of the local Nusselt number eliminate the need to determine surface normal and temperature gradient in the normal direction for heat transfer calculation, which is particularly beneficial in cases with deforming or changing boundaries.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 24 no. 1
Type: Research Article
ISSN: 0961-5539

Keywords

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Article

Heng Sun and David Ross

The MRT lattice Boltzmann simulation of natural convection in a confined environment is carried out. The flow and heat transfer during natural convection in a symmetrical…

Abstract

Purpose

The MRT lattice Boltzmann simulation of natural convection in a confined environment is carried out. The flow and heat transfer during natural convection in a symmetrical annulus are studied.

Design/methodology/approach

The cavity is filled with TiO2-water nanofluid, and the thermal conductivity and dynamic viscosity of nanofluid are measured experimentally. The experimental data are utilized in the numerical simulations. The nanofluids are prepared at four different nanoparticle concentrations φ = 0, 0.1, 0.3 and 0.5. It is notable that the radial coordinate is used into the temperature distribution function. As a result, only one source term is required for the present lattice Boltzmann model. On the other hand, the macro cylindrical energy equation is exactly recovered using Chapman–Enskog analysis.

Findings

Influence of some main parameters including Rayleigh number in range of 103 to 106, solid volume fraction of nanofluid in range of 0 to 0.5 and four different aspect ratios on the the nanofluid flow (i.e. streamlines), heat transfer (i.e. temperature distribution and average Nusselt number) and entropy generation (i.e. total entropy generation and Bejan number) are presented, quantitatively and graphically. It is found that adding TiO2 nanoparticles to the base fluid has considerable positive effect on the heat transfer performance and entropy generation. In addition, the configuration of the annulus can be good controlling parameter on the heat transfer rate during natural convection.

Originality/value

The originality of this work is using of a modern numerical method to simulate the free convection and conducting experimental observations to calculate the thermo-physical properties of nanofluid. In addition, the numerical and experimental works are combined to provide accurate results.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 2
Type: Research Article
ISSN: 0961-5539

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Article

Peng Zhang, Muhammad Aqeel Ashraf, Zhenling Liu, Wan-Xi Peng and David Ross

This paper aims to investigate the free convection, heat transfer and entropy generation numerically and experientially. A numerical/experimental investigation is carried…

Abstract

Purpose

This paper aims to investigate the free convection, heat transfer and entropy generation numerically and experientially. A numerical/experimental investigation is carried out to investigate the free convection hydrodynamically/thermally and entropy generation.

Design/methodology/approach

The coupled lattice Boltzmann method is used as a numerical approach which keeps the significant advantages of standard lattice Boltzmann method with better numerical stability. On the other hand, the thermal conductivity and dynamic viscosity are measured using modern devices in the laboratory.

Findings

Some correlations based on the temperature at different nanofluid concentration are derived and used in the numerical simulations. In this regard, the results will be accurate with respect to using theoretical properties of nanofluid, and close agreements will be detected between present results and the previous numerical and experimental works. The numerical investigation is done under the effect of Rayleigh number (103 < Ra < 106), volume concentration of nanofluid (?? = 0.5, 1, 1.5, 2, 2.5 and 3%) and thermal configuration of the cavity (Cases A, B, C and D).

Originality/value

The originality of the present work lies in coupling of the lattice Boltzmann method with experimental observations to analyse the free convection in a cavity.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 3
Type: Research Article
ISSN: 0961-5539

Keywords

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Article

Mohamed Amine Moussaoui, Mohamed Jami, Ahmed Mezrhab and Hassan Naji

The purpose of this paper is to investigate the laminar flow and heat transfer characteristics in a two‐dimensional horizontal channel with two square blocks placed…

Abstract

Purpose

The purpose of this paper is to investigate the laminar flow and heat transfer characteristics in a two‐dimensional horizontal channel with two square blocks placed side‐by‐side using a numerical scheme based on a coupling between the lattice Boltzmann method and the finite difference method.

Design/methodology/approach

The multiple‐relaxation‐time (MRT) lattice Boltzmann equation model coupled with the finite difference method are used to predict numerically the velocity and the temperature fields.

Findings

A complex structure of the fluid flow was observed for various dimensionless block separation distance (G). An unsteady flow was found when the two blocks are placed side by side (G = 0). For G < 1.5, the presence of each block develops the street of Van Karman which generates complex binary vortex street. In the opposite case (G > 1.5), the effect of this parameter (G) on the fluid is reduced, whereas, the distance between the blocks and the nearest walls have a great influence on the fluid flow and the heat transfer. When the obstacles are posed on the walls (G = 3), an important heat exchange between the blocks and the nearest walls is noted.

Originality/value

This study offers more knowledge on natural convection in an obstructed channel. Furthermore, this work shows the effectiveness of the MRT lattice Boltzmann equation model for this kind of geometry.

Details

Engineering Computations, vol. 27 no. 1
Type: Research Article
ISSN: 0264-4401

Keywords

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Article

Alireza Rahimi, Hesam Bakhshi, Ali Dehghan Saee, Abbas Kasaeipoor and Emad Hasani Malekshah

The study aims to study the nanofluid flow and heat transfer in a T-shaped heat exchanger. For the numerical simulations, the lattice Boltzmann method is used.

Abstract

Purpose

The study aims to study the nanofluid flow and heat transfer in a T-shaped heat exchanger. For the numerical simulations, the lattice Boltzmann method is used.

Design/methodology/approach

The end of each branch of the heat exchanger is considered a curve wall that requires special thermal and physical boundary conditions. To improve the thermal performance of the heat exchanger, the CuO–water nanofluid, which has better heat transfer performance with respect to pure water, is used. The dynamic viscosity of nanofluid is estimated by means of KKL model. Several active fins and solid bodies are implanted within the heat exchanger with different thermal arrangements.

Findings

In the present work, different approaches such as heatline visualization, local and total entropy generation analysis, local and total Nusselt variation are used to detect the impact of different considered parameters such as Rayleigh number (103 < Ra < 106), solid volume fraction of nanofluid (φ = 0,0.01,0.02,0.03 and 0.04 vol. per cent) and thermal arrangements of internal bodies (Case A, Case B, Case C and Case D) on the fluid flow and heat transfer performance.

Originality/value

The originality of this work is to analyze the two-dimensional natural convection and entropy generation using lattice Boltzmann method.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 1
Type: Research Article
ISSN: 0961-5539

Keywords

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Article

Lin Deng, Junjie Liang, Yun Zhang, Huamin Zhou and Zhigao Huang

Lattice Boltzmann method (LBM) has made great success in computational fluid dynamics, and this paper aims to establish an efficient simulation model for the polymer…

Abstract

Purpose

Lattice Boltzmann method (LBM) has made great success in computational fluid dynamics, and this paper aims to establish an efficient simulation model for the polymer injection molding process using the LBM. The study aims to validate the capacity of the model for accurately predicting the injection molding process, to demonstrate the superior numerical efficiency in comparison with the current model based on the finite volume method (FVM).

Design/methodology/approach

The study adopts the stable multi-relaxation-time scheme of LBM to model the non-Newtonian polymer flow during the filling process. The volume of fluid method is naturally integrated to track the movement of the melt front. Additionally, a novel fractional-step thermal LBM is used to solve the convection-diffusion equation of the temperature field evolution, which is of high Peclet number. Through various simulation cases, the accuracy and stability of the present model are validated, and the higher numerical efficiency verified in comparison with the current FVM-based model.

Findings

The paper provides an efficient alternative to the current models in the simulation of polymer injection molding. Through the test cases, the model presented in this paper accurately predicts the filling process and successfully reproduces several characteristic phenomena of injection molding. Moreover, compared with the popular FVM-based models, the present model shows superior numerical efficiency, more fit for the future trend of parallel computing.

Research limitations/implications

Limited by the authors’ hardware resources, the programs of the present model and the FVM-based model are run on parallel up to 12 threads, which is adequate for most simulations of polymer injection molding. Through the tests, the present model has demonstrated the better numerical efficiency, and it is recommended for the researcher to investigate the parallel performance on even larger-scale parallel computing, with more threads.

Originality/value

To the authors’ knowledge, it is for the first time that the lattice Boltzmann method is applied in the simulation of injection molding, and the proposed model does obviously better in numerical efficiency than the current popular FVM-based models.

Details

Engineering Computations, vol. 34 no. 2
Type: Research Article
ISSN: 0264-4401

Keywords

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Article

Antonio Fabio Di Rienzo, Pietro Asinari, Romano Borchiellini and Sunhash C. Mishra

The purpose of this paper is to present and validate some improvements to the lattice Boltzmann method (LBM) for solving radiative heat transfer in a participating medium…

Abstract

Purpose

The purpose of this paper is to present and validate some improvements to the lattice Boltzmann method (LBM) for solving radiative heat transfer in a participating medium. Validation of the model is performed by investigating the effects of spatial and angular discretizations and extinction coefficient on the solution. The error analysis and the order of convergence of the scheme are also reported.

Design/methodology/approach

LB scheme is derived from the radiative transfer equation, where isotropic scattering and radiative equilibrium condition are assumed. Azimuthal angle is discretized according to the lattice velocities on the computational plane, while, concerning the polar angle, an additional component of the discrete velocity normal to the plane is introduced. Radiative LB scheme is used to solve a 2‐D square enclosure benchmark problem. In order to validate the model, results of LB scheme are compared with a reference solution obtained through a Richardson extrapolation of the results of a standard finite volume method.

Findings

The proposed improvements drastically increase the accuracy of the previous method. Radiative LB scheme is found to be (at most) first order accurate. Numerical results show that solution gets more accurate when spatial and azimuthal angle discretizations are improved, but a saturation threshold exists. With regard to polar angle, minimum error occurs when a particular subdivision is considered.

Originality/value

The paper provides simple but effective improvements to the recently proposed lattice Boltzmann method for solving radiative heat transfer in a participating medium.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 21 no. 5
Type: Research Article
ISSN: 0961-5539

Keywords

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Article

Rasul Mohebbi, Mohsen Izadi, Nor Azwadi Che Sidik and Gholamhassan Najafi

This paper aims to study the natural convection of a nanofluid inside a cavity which contains obstacles using lattice Boltzmann method (LBM). The results have focused…

Abstract

Purpose

This paper aims to study the natural convection of a nanofluid inside a cavity which contains obstacles using lattice Boltzmann method (LBM). The results have focused mainly on various parameters such as number and aspect ratio of roughness elements and different nanoparticle volume fraction. The isotherms and streamlines are presented to describe the hydrodynamics and thermal behaviors of the nanofluid flow throughout the enclosure.

Design/methodology/approach

The methodology of this paper consists of mathematical model, statement of the problem, nanofluid thermophysical properties, lattice Boltzmann method, LBM for fluid flow, LBM for heat transfer, numerical strategy, boundary conditions, Nusselt (Nu) number calculation, code validation and grid independence.

Findings

Natural convection heat transfers of a nanofluid inside cavities with and without rough elements have been studied. Lattice Boltzmann technique has been used as numerical approach. The results showed that at higher Rayleigh number (Ra = 106), there are denser streamlines near the left (source) and right wall (sink) which results in better cooling and enhances convective heat rejection to the heat sink. After a distinctive aspect ratio of rough elements (A =0.1), change in streamline pattern which arises from increasing of aspect ratio does not have an important effect on isotherms. Results indicate that for lower Rayleigh number (Ra =103), no variation in average Nu is observed with increasing in number of roughness, while for higher one (Ra = 106) average Nu decreases from N = 0 (smooth cavity) up to N = 4 and then remains constant (N = 6).

Originality/value

Currently, no argumentative and comprehensive extraction can be concluded without fully understanding the role of different arrangement of roughness. Some geometrical parameters such as aspect ratio, number and position of rough elements have been considered. Also, the effect of nanoparticle concentration was studied at different Ra number. Briefly, using LBM, this paper aims to investigate the natural convection of a nanofluid flow on the thermal and hydrodynamics parameters in the presence of rough element with various arrangements.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 10
Type: Research Article
ISSN: 0961-5539

Keywords

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