Macroscopic lattice Boltzmann model for heat and moisture transfer process with phase transformation in unsaturated porous media during freezing process

AbstractIn the current study, a macroscopic lattice Boltzmann model for simulating the heat and moisture transport phenomenon in unsaturated porous media during the freezing process was proposed. The proposed model adopted percolation threshold to reproduce the extra resistance in frozen fringe during the freezing process. The freezing process in Kanagawa sandy loam soil was demonstrated by the proposed model. The numerical result showed good agreement with the experimental result. The proposed model also offered higher computational efficiency and better agreement with the experimental result than the existing numerical models. Lattice Boltzmann method is suitable for simulating complex heat and mass transfer process in porous media at macroscopic scale under proper dimensionless criterion, which makes it a potentially powerful tool for engineering application.

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Abnormal Prediction of Dense Crowd Videos by a Purpose–Driven Lattice Boltzmann Model

International Journal of Applied Mathematics and Computer Science ◽

10.1515/amcs-2017-0013 ◽

2017 ◽

Vol 27 (1) ◽

pp. 181-194 ◽

Cited By ~ 3

Author(s):

Yiran Xue ◽

Peng Liu ◽

Ye Tao ◽

Xianglong Tang

Keyword(s):

Lattice Boltzmann ◽

General Trend ◽

Lattice Boltzmann Model ◽

Training Procedure ◽

Particle Collisions ◽

Proposed Model ◽

Dense Crowds ◽

Dense Crowd ◽

Boltzmann Model ◽

Abnormal Events

Abstract In the field of intelligent crowd video analysis, the prediction of abnormal events in dense crowds is a well-known and challenging problem. By analysing crowd particle collisions and characteristics of individuals in a crowd to follow the general trend of motion, a purpose-driven lattice Boltzmann model (LBM) is proposed. The collision effect in the proposed method is measured according to the variation in crowd particle numbers in the image nodes; characteristics of the crowd following a general trend are incorporated by adjusting the particle directions. The model predicts dense crowd abnormal events in different intervals through iterations of simultaneous streaming and collision steps. Few initial frames of a video are needed to initialize the proposed model and no training procedure is required. Experimental results show that our purpose-driven LBM performs better than most state-of-the-art methods.

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Extending a Gray Lattice Boltzmann Model for Simulating Fluid Flow in Multi-Scale Porous Media

Scientific Reports ◽

10.1038/s41598-018-24151-2 ◽

2018 ◽

Vol 8 (1) ◽

Cited By ~ 4

Author(s):

Jiujiang Zhu ◽

Jingsheng Ma

Keyword(s):

Porous Media ◽

Fluid Flow ◽

Lattice Boltzmann ◽

Lattice Boltzmann Model ◽

Multi Scale ◽

Boltzmann Model

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A lattice Boltzmann model for heat transfer in porous media

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2017.04.054 ◽

2017 ◽

Vol 111 ◽

pp. 1019-1022 ◽

Cited By ~ 8

Author(s):

Sheng Chen ◽

Bo Yang ◽

Chuguang Zheng

Keyword(s):

Heat Transfer ◽

Porous Media ◽

Lattice Boltzmann ◽

Lattice Boltzmann Model ◽

Boltzmann Model

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An improved enthalpy-based lattice Boltzmann model for heat and mass transfer of the freezing process

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2016.06.122 ◽

2017 ◽

Vol 111 ◽

pp. 1477-1486 ◽

Cited By ~ 6

Author(s):

Xin Zhao ◽

Bo Dong ◽

Weizhong Li ◽

Binlin Dou

Keyword(s):

Mass Transfer ◽

Heat And Mass Transfer ◽

Lattice Boltzmann ◽

Lattice Boltzmann Model ◽

Freezing Process ◽

Boltzmann Model

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Lattice Boltzmann Model for Gas Flow through Tight Porous Media with Multiple Mechanisms

Entropy ◽

10.3390/e21020133 ◽

2019 ◽

Vol 21 (2) ◽

pp. 133 ◽

Cited By ~ 2

Author(s):

Junjie Ren ◽

Qiao Zheng ◽

Ping Guo ◽

Chunlan Zhao

Keyword(s):

Porous Medium ◽

Porous Media ◽

Lattice Boltzmann ◽

Gas Flow ◽

Stress Sensitivity ◽

Lattice Boltzmann Model ◽

Flow Through Porous Media ◽

Gas Slippage ◽

Flow Through ◽

Boltzmann Model

In the development of tight gas reservoirs, gas flow through porous media usually takes place deep underground with multiple mechanisms, including gas slippage and stress sensitivity of permeability and porosity. However, little work has been done to simultaneously incorporate these mechanisms in the lattice Boltzmann model for simulating gas flow through porous media. This paper presents a lattice Boltzmann model for gas flow through porous media with a consideration of these effects. The apparent permeability and porosity are calculated based on the intrinsic permeability, intrinsic porosity, permeability modulus, porosity sensitivity exponent, and pressure. Gas flow in a two-dimensional channel filled with a homogeneous porous medium is simulated to validate the present model. Simulation results reveal that gas slippage can enhance the flow rate in tight porous media, while stress sensitivity of permeability and porosity reduces the flow rate. The simulation results of gas flow in a porous medium with different mineral components show that the gas slippage and stress sensitivity of permeability and porosity not only affect the global velocity magnitude, but also have an effect on the flow field. In addition, gas flow in a porous medium with fractures is also investigated. It is found that the fractures along the pressure-gradient direction significantly enhance the total flow rate, while the fractures perpendicular to the pressure-gradient direction have little effect on the global permeability of the porous medium. For the porous medium without fractures, the gas-slippage effect is a major influence factor on the global permeability, especially under low pressure; for the porous medium with fractures, the stress-sensitivity effect plays a more important role in gas flow.

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