632 Numerical analysis of gas flows caused by evaporation and condensation on two parallel plates using the finite difference lattice Boltzmann method

In this study the two-dimensional flow over a square cylinder placed in a parallel plates is simulated numerically by using lattice Boltzmann method (LBM) at low Reynolds numbers. Both the plates are obstructed by solid rectangular blocks of variable length. The fluid was allowed to flow in a parallel plates for Reynolds number (Re) from 75 to 150, and blockage ratio (g*) ranges from 1 to 3. The numerical investigation does not simply yield the predictable primary region of recirculating flow connected to the obstructions, it also shows supplementary regions of the flow downstream of the single cylinder placed in a computational domain. These supplementary separation zones were not already described in the research. The numerical analysis shows that the downstream flow of obstructions and single cylinder remained two dimensional for Re varied from75 to 150. Results available in previous research, are reported and compared with both of the available experimental and numerical results for code validation with single cylinder. Furthermore the effects of various Re and blockage ratio on the lift forces and drag coefficient is analyzed. Under these circumstances, good agreement between experimental and numerical results are obtained. The hydrodynamic forces of the cylinder are strongly influenced by the spacing ratios.

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S0802-1-1 Numerical Analysis of Flow-Acoustic Coupling Resonance in Multiple Side Branches Usinq the Finite Difference Lattice Boltzmann Method

The proceedings of the JSME annual meeting ◽

10.1299/jsmemecjo.2010.3.0_145 ◽

2010 ◽

Vol 2010.3 (0) ◽

pp. 145-146

Author(s):

Akinori TAMURA ◽

Keita OKUYAMA ◽

Shiro TAKAHASHI ◽

Masaya OHTSUKA

Keyword(s):

Numerical Analysis ◽

Finite Difference ◽

Lattice Boltzmann Method ◽

Lattice Boltzmann ◽

Acoustic Coupling ◽

Boltzmann Method

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Rotational Slip Flow in Coaxial Cylinders by the Finite-Difference Lattice Boltzmann Methods

Communications in Computational Physics ◽

10.4208/cicp.231009.091110s ◽

2011 ◽

Vol 9 (5) ◽

pp. 1293-1314 ◽

Cited By ~ 7

Author(s):

Minoru Watari

Keyword(s):

Finite Difference ◽

Lattice Boltzmann Method ◽

Lattice Boltzmann ◽

Slip Flow ◽

Velocity Slip ◽

Parallel Plates ◽

Coaxial Cylinders ◽

Cylindrical Coordinate ◽

Boltzmann Method ◽

Rotational Slip

AbstractRecent studies on applications of the lattice Boltzmann method (LBM) and the finite-difference lattice Boltzmann method (FDLBM) to velocity slip simulations are mostly on one-dimensional (1D) problems such as a shear flow between parallel plates. Applications to a 2D problem may raise new issues. The author performed numerical simulations of rotational slip flow in coaxial cylinders as an example of 2D problem. Two types of 2D models were used. The first were multi-speed FDLBM models proposed by the author. The second was a standard LBM, the D2Q9 model. The simulations were performed applying a finite difference scheme to both the models. The study had two objectives. The first was to investigate the accuracies of LBM and FDLBM on applications to rotational slip flow. The second was to obtain an experience on application of the cylindrical coordinate system. The FDLBM model with 8 directions and the D2Q9 model showed an anisotropic flow pattern when the relaxation time constant or the Knudsen number was large. The FDLBM model with 24 directions showed accurate results even at large Knudsen numbers.

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