Bouchmel Mliki, Mohamed Ammar Abbassi, Ahmed Omri

FDMP-Fluid Dynamics & Materials Processing, Vol.11, No.1, pp. 87-114, 2015, DOI:10.3970/fdmp.2015.011.087

Abstract MHD double-diffusive natural convective flow in a C-shaped enclosure filled with a Cu/Water nanofluid is investigated numerically using the Lattice Boltzmann Method (LBM). Much care is devoted to the validation of the numerical code. The effects exerted on the flow, concentration and temperature fields by different parameters such as the Rayleigh number (10³−10⁶), the nanoparticle volume concentration (0−0,1), the Lewis number (1-5), the Hartmann number (0−30) and different types of nanoparticles (Cu, Ag, Al₂O₃ and TiO₃ are assessed in detail. Results for stream function, Nusselt and Sherwood numbers are presented and discussed for various parametric conditions. Results indicate that the… More >

H. Chanson¹, K.K. Tan²

FDMP-Fluid Dynamics & Materials Processing, Vol.7, No.4, pp. 403-418, 2011, DOI:10.3970/fdmp.2011.007.403

Abstract A tidal bore is a wall of water propagating upstream as the tidal flow turns to rising into an estuary with a tidal range larger than 5 to 6 m and the bathymetry that amplifies the tidal wave. The bore front is a shock characterised by a singularity of the free-surface and pressure and velocity fields. This study aims to characterise the impact of tidal bores on the turbulent dispersion of fish eggs. Some physical modelling was performed based upon a Froude similitude and the tracking of plastic beads acting as fish egg proxies was conducted under controlled flow conditions… More >

R. Abdeljabar¹

FDMP-Fluid Dynamics & Materials Processing, Vol.7, No.2, pp. 217-230, 2011, DOI:10.3970/fdmp.2011.007.217

Abstract In this paper, we discuss a new technique for desalination based on the principles of the Soret effect. In particular, the method stems from the peculiar behavior of the solute in a solution of sodium chloride (i.e. salty water layer) of uniform concentration being less or equal to 5wt% under the effect of an imposed temperature gradient with average temperature equal to 12oC. The Soret coefficient may be positive or negative according to whether the temperature of the solution is above or below 12oC. As two diffusion processes (one parallel to the temperature gradient and the other anti-parallel) can occur… More >

M. Chrigui^1,2, L. Schneider¹, A. Zghal², A. Sadiki¹, J. Janicka¹

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.4, pp. 399-408, 2010, DOI:10.3970/fdmp.2010.006.399

Abstract This paper deals with the numerical simulation of droplet dispersion and evaporation within an LPP (Lean Premix Prevaporized) burner. The Eulerian-Lagrangian approach was used for this purpose, and a fully two way-coupling was accounted for. For the phase transition, a non-equilibrium evaporation model was applied that differs strongly from the equilibrium one where there are high evaporation rates. The non-equilibrium conditions were fulfilled in the investigated configuration, as the droplets at the inlet had a mean diameter of 50mm. The numerical results of water droplet velocities, corresponding fluctuations, and diameters were compared with experimental data. Good agreement was found. More >

A. Radhouane¹, N. Mahjoub Said¹, H. Mhiri¹, G. Le Palec², P. Bournot²

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.4, pp. 385-398, 2010, DOI:10.3970/fdmp.2010.006.385

Abstract "Twin jets in crossflow" is a complex configuration that raises an increasing interest due to its presence in various common applications such as chimney stacks, film cooling, VSTOL aircrafts, etc... In the present paper, the twin jets were arranged inline with an oncoming crossflow;they were also inclined which resulted in similar elliptic cross sections of the nozzles' exits. The exploration of the flows in interaction was carried out numerically by means of the finite volume method together with the second order turbulent closure model, namely the Reynolds stress Model (RSM), and a non uniform grid system particularly refined near the… More >

A. Belcaid^1,2, G. Le Palec², A. Draoui¹, Ph. Bournot¹

FDMP-Fluid Dynamics & Materials Processing, Vol.8, No.2, pp. 241-256, 2012, DOI:10.3970/fdmp.2012.008.241

Abstract The study is focused on numerical simulation of the process of coastal pollution by wastewater in the Bay of Tangier in Morocco. The process is governed by flows generated by the tide and the large variations of the discharges from the different Wadis (rivers) flowing into the bay. The simulation requires a number of tests and trials, something that is experimentally expensive and sometimes impossible. Hence the idea was developed of a numerical study aimed at tracking the dispersion of pollutants into the bay and determining the level of degradation of its waters. The simulation was done using the computer… More >

Chein-Shan Liu¹, Chih-Wen Chang², Jiang-Ren Chang^2,3

CMC-Computers, Materials & Continua, Vol.9, No.2, pp. 111-136, 2009, DOI:10.3970/cmc.2009.009.111

Abstract In this paper, we take the advantage of an analytical method to solve the advection-dispersion equation (ADE) for identifying the contamination problems. First, the Fourier series expansion technique is employed to calculate the concentration field C(x, t) at any time t< T. Then, we consider a direct regularization by adding an extra term αC(x,0) on the final condition to carry off a second kind Fredholm integral equation. The termwise separable property of the kernel function permits us to transform itinto a two-point boundary value problem. The uniform convergence and error estimate of the regularized solution C^α(x,t) are provided and a… More >

Ping’en Li^1,2, Xianyue Su^1,3

CMC-Computers, Materials & Continua, Vol.8, No.3, pp. 173-194, 2008, DOI:10.3970/cmc.2008.008.173

Abstract Applying the Stroh theory and based on the works of Hwu and Ting (1989), the complex function solution of stress and displacement fields around an open borehole in intrinsic anisotropic formation under horizontal terrestrial stress field is obtained. For cross-dipole flexural wave propagation along borehole axis, using the perturbation method, the acoustoelastic equation describing the relation between the alteration in phase velocity and terrestrial stress as well as formation intrinsic anisotropy is derived. At last, the numerical examples are provided for both the cases of fast and slow formation where the symmetry axis of a transversely isotropic (TI) formation makes… More >

Ping’en Li¹, Xianyue Su^1,2, Youquan Yin¹

CMC-Computers, Materials & Continua, Vol.6, No.2, pp. 93-102, 2007, DOI:10.3970/cmc.2007.006.093

Abstract Based on the perturbation method, for flexural wave in cased hole in anisotropic formation, the alteration in the phase velocity caused by the differences in elastic constants between anisotropic formation of interest and a reference, or unperturbed isotropic formation is obtained. Assuming the cased hole is well bonded, the Thomson-Haskell transfer matrix method is applied to calculate the dispersion relation of flexural wave in cased hole in unperturbed isotropic formation. Both the cases of a fast and slow formation are considered where the symmetry axis of a transversely isotropic (TI) formation makes an angle with the cased hole axis, the… More >

G. Q. Xie^1,2,3, X. Han², S. Y. Long³

CMC-Computers, Materials & Continua, Vol.6, No.1, pp. 1-12, 2007, DOI:10.3970/cmc.2007.006.001

Abstract A multi-walled carbon nanotube is modeled as a multiple-elastic cylindrical structure. The numerical-analytical method is adopted to analyze the characteristics of harmonic waves propagating along an anisotropic carbon nanotube. Each wall of the carbon nanotube is divided into three-nodal-line layer elements. The deflections of two adjacent tubes are coupled through the van der Waals. The governing equation of element is obtained from Hamilton's principle. A set of system equation of dynamics equilibrium for the entire structure is obtained by the assembling of all the elements. From solution of the eigenvalue equations, the dispersive characteristics, group velocities of multi-walled carbon nanotubes… More >