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Guo Z.,Beijing Petroleum and Oil Institute | Guo Z.,National Laboratory of Coal Combustion | Shi B.,Huazhong University of Science and Technology | Zheng C.,National Laboratory of Coal Combustion
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences | Year: 2011

Spurious currents near an interface between different phases are a common undesirable feature of the lattice Boltzmann equation (LBE) method for two-phase systems. In this paper, we show that the spurious currents of a kinetic theory-based LBE have a significant dependence on the parity of the grid number of the underlying lattice, which can be attributed to the chequerboard effect. A technique that uses a Lax-Wendroff streaming is proposed to overcome this anomaly, and its performance is verified numerically. © 2011 The Royal Society. Source

Wang L.,Huazhong University of Science and Technology | Guo Z.,Huazhong University of Science and Technology | Guo Z.,Beijing Petroleum and Oil Institute | Zheng C.,Huazhong University of Science and Technology
Computers and Fluids | Year: 2010

In this paper, a lattice-Boltzmann equation (LBE) with multi relaxation times (MRT) is presented for axisymmetric flows. The model is an extension of a recent model with single-relaxation-time [Guo et al., Phys. Rev. E 79, 046708 (2009)], which was developed based on the axisymmetric Boltzmann equation. Due to the use of the MRT collision model, the present model can achieve better numerical stability. The model is validated by some numerical tests including the Hagen-Poiseuille flow, the pulsatile Womersley flow, and the external flow over a sphere. Numerical results are in excellent agreement with analytical solutions or other available data, and the improvement in numerical stability is also confirmed. © 2010 Elsevier Ltd. Source

Liu X.,Huazhong University of Science and Technology | Liu X.,Shanghai JiaoTong University | Guo Z.,Huazhong University of Science and Technology | Guo Z.,Beijing Petroleum and Oil Institute
Computers and Mathematics with Applications | Year: 2013

In this paper, the pressure-driven flow in a long micro-channel is studied via a lattice Boltzmann equation (LBE) method. With the inclusion of the gas-wall collision effects, the LBE is able to capture the flow behaviors in the transition regime. The numerical results are compared with available data of other methods. Furthermore, the effects of rarefaction and compressibility on the deviation of the pressure distribution from the linear one are also investigated. © 2011 Elsevier Ltd. All rights reserved. Source

Guo Z.,Huazhong University of Science and Technology | Guo Z.,Beijing Computational Science Research Center | Qin J.,Beijing Petroleum and Oil Institute | Zheng C.,Huazhong University of Science and Technology
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2014

It is a challenging task to model nonequilibrium gas flows within a continuum-fluid framework. Recently some extended hydrodynamic models in the Navier-Stokes formulation have been developed for such flows. A key problem in the application of such models is that suitable boundary conditions must be specified. In the present work, a generalized second-order slip boundary condition is developed in which an effective mean-free path considering the wall effect is used. By combining this slip scheme with certain extended Navier-Stokes constitutive relation models, we obtained a method for nonequilibrium gas flows with solid boundaries. The method is applied to several rarefied gas flows involving planar or curved walls, including the Kramers' problem, the planar Poiseuille flow, the cylindrical Couette flow, and the low speed flow over a sphere. The results show that the proposed method is able to give satisfied predictions, indicating the good potential of the method for nonequilibrium flows. © 2014 American Physical Society. Source

Zhang K.,Beijing Petroleum and Oil Institute
Petroleum Science and Technology | Year: 2014

Zeolite grains are pretty effective in blocking highly permeable strata. The author observed the chemical component and exterior construct of zeolite, measured adsorptive ability of the zeolite in the polymer carrying solution, evaluated the blocking and flooding effect, and analyzed the mechanism. The results show that the size of the grain and density of the solution, injection time, slug size, and how the zeolite and polymer slug combined affect blocking and flooding effects. Experiments at Lama-dian oilfield showed that a zeolite-polymer solution is extremely effective in blocking the extra-high-permeability strata. © 2014 Copyright Chinese Academy of Sciences. Source

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