Pore-scale prediction of the effective mass diffusivity of heterogeneous shale structure using the lattice Boltzmann method
| Autor: | Jianfei Zhang, Ying Yin, Zhiguo Qu |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Fluid Flow and Transfer Processes
Materials science Mechanical Engineering Lattice Boltzmann methods Thermodynamics 02 engineering and technology 021001 nanoscience & nanotechnology Condensed Matter Physics Thermal diffusivity 01 natural sciences Physics::Geophysics 010305 fluids & plasmas Effective mass (solid-state physics) Physics::Space Physics 0103 physical sciences Volume fraction Empirical formula 0210 nano-technology Porosity Porous medium Oil shale |
| Zdroj: | International Journal of Heat and Mass Transfer. 133:976-985 |
| ISSN: | 0017-9310 |
| Popis: | Shale is a kind of heterogeneous porous medium consisting of organic matter (OM), inorganic matter (IM), and interparticle pores. A modified lattice Boltzmann model is developed at the pore-scale to accurately predict the effective mass diffusivity of the heterogeneous shale structure by fully considering the multicomponent and irregular morphological features. The model is validated by the classic empirical formulas and numerical results of the shale with regular IM and OM skeletons. The effects of average gain diameter, irregular structural morphology, porosity, OM volume fraction, and OM diffusivity on the effective mass diffusivity are investigated. The effect of average gain diameter can be ignored. The Nield formula is capable of predicting the effective mass diffusivity of a random OM structure. The formula of Comiti and Renaud can be extended to predict the effective mass diffusivity of a random IM structure by modifying the empirical coefficient to 1.6. The effective mass diffusivity of the heterogeneous shale structure with random OM and IM is between that of pure IM and OM. This effective mass diffusivity increases with the increment of porosity, OM volume fraction, and OM diffusivity. A general empirical formula is proposed to calculate the effective mass diffusivity effectively and conveniently. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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