Tounsi Chati^a,* , Kouider Rahmani^b, Toufik Tayeb Naas^c, Abdelkader Rouibah^b

Frontiers in Heat and Mass Transfer, Vol.18, No.1, pp. 1-11, 2022, DOI:10.5098/hmt.18.19

Abstract Numerical results of turbulent natural convection and mass transfer in an open enclosure for different aspect ratios (AR = 0.5, 1, and 2) with a humidair are carried out. Mass fraction and local Nusselt number were proposed to investigate the heat and mass transfer. A heat flux boundary conditions were subjected to the lateral walls and the bottom one make as an adiabatic wall, while the top area was proposed as a free surface. Effect of Rayleigh numbers (10⁶ ≤ More >

Y. Nishio^1,*, B. Janssens¹, K. Limam², J. van Beeck³

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.3, pp. 743-753, 2023, DOI:10.32604/fdmp.2022.021848

Abstract A LES model is proposed to predict the dispersion of particles in the atmosphere in the context of Chemical, Biological, Radiological and Nuclear (CBRN) applications. The code relies on the Finite Element Method (FEM) for both the fluid and the dispersed solid phases. Starting from the Navier-Stokes equations and a general description of the FEM strategy, the Streamline Upwind Petrov-Galerkin (SUPG) method is formulated putting some emphasis on the related assembly matrix and stabilization coefficients. Then, the Variational Multiscale Method (VMS) is presented together with a detailed illustration of its algorithm and hierarchy of computational steps. It is demonstrated that… More >

Matthew Wilkinson, Javier Villarreal, Andrew Meade^*

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.3, pp. 1373-1393, 2021, DOI:10.32604/cmes.2021.017883

Abstract A meshless and matrix-free fluid dynamics solver (SOMA) is introduced that avoids the need for user generated and/or analyzed grids, volumes, and meshes. Incremental building of the approximation avoids creation and inversion of possibly dense block diagonal matrices and significantly reduces user interaction. Validation results are presented from the application of SOMA to subsonic, compressible, and turbulent flow over an adiabatic flat plate. More >

Abid. A. Memon¹, M. Asif Memon¹, Kaleemullah Bhatti¹, Kamsing Nonlaopon^2,*, Ilyas Khan³

CMC-Computers, Materials & Continua, Vol.70, No.3, pp. 4341-4355, 2022, DOI:10.32604/cmc.2022.019407

Abstract This article is intended to examine the fluid flow patterns and heat transfer in a rectangular channel embedded with three semi-circular cylinders comprised of steel at the boundaries. Such an organization is used to generate the heat exchangers with tube and shell because of the production of more turbulence due to zigzag path which is in favor of rapid heat transformation. Because of little maintenance, the heat exchanger of such type is extensively used. Here, we generate simulation of flow and heat transfer using non-isothermal flow interface in the Comsol multiphysics 5.4 which executes the Reynolds averaged Navier stokes equation… More >

Younes Noorollahi^1,2,*, Mohammad-Javad Ziabakhsh Ganji¹, Mohammadmahdi Rezaei^1,2, Mojtaba Tahani³

CMES-Computer Modeling in Engineering & Sciences, Vol.127, No.2, pp. 515-532, 2021, DOI:10.32604/cmes.2021.012386

Abstract

Nowadays, concerns arise because of the depletion of fossil fuel resources that forced scientists to develop new energy extraction methods. One of these renewable resources is tidal energy, where Iran has this potential significantly. There are many ways to obtain the kinetic energy of the fluid flow caused by the moon’s gravitational effect on seas. Using horizontal axis tidal turbines is one of the ways to achieve the kinetic energy of the fluid. Since this type of turbine has similar technology to horizontal axis wind turbines, they may be an appropriate choice for constructing a tidal power plant in Iran.… More >

Yousuke Shimoda¹, Takahiro Matsumori¹, Kazuki Sato¹, Tatsuro Hirano¹, Naoya Fukushima^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.23, No.1, pp. 16-16, 2021, DOI:10.32604/icces.2021.08337

Abstract Along with rapid development of computer technologies, a wide range of turbulent flows have been investigated by direct numerical simulations and the big databases have been built throughout the world. From the DNS results, we can investigate turbulent characteristics in three-dimensional space and time. In the laboratory experiment, we can apply sophisticated laser diagnostics technique to measure flow field non-invasively in research. On actual equipment, it is very difficult to get the flow field data away from the wall. We can measure only wall information, such as wall shear stresses and pressure. When we predict turbulence from wall information, we… More >

Jingfa Li¹, Bo Yu^1,*, Qianqian Shao², Dongliang Sun¹

CMES-Computer Modeling in Engineering & Sciences, Vol.125, No.2, pp. 541-563, 2020, DOI:10.32604/cmes.2020.011835

Abstract In this work, the drag-reducing mechanism of high-Reynoldsnumber turbulent channel flow with surfactant additives is investigated by using large eddy simulation (LES) method. An N-parallel finitely extensible nonlinear elastic model with Peterlin’s approximation (FENE-P) is used to describe the rheological behaviors of non-Newtonian fluid with surfactant. To close the filtered LES equations, a hybrid subgrid scale (SGS) model coupling the spatial filter and temporal filter is applied to compute the subgrid stress and other subfilter terms. The finite difference method and projection algorithm are adopted to solve the LES governing equations. To validate the correctness of our LES method and… More >

D. O. Redchyts¹, E. A. Shkvar^{2, *}, S. V. Moiseienko³

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.1, pp. 91-103, 2020, DOI:10.32604/fdmp.2020.07933

Abstract A method to evaluate the properties of turbulent flow in proximity to the vehicle and close to the ground surface has been elaborated. Numerical simulations have been performed on the basis of the Unsteady Reynolds-averaged Navier-Stokes equations (URANS) written with respect to an arbitrary curvilinear coordinate system. These equations have been solved using the Spalart-Allmaras differential one-parametric turbulence model. The method of artificial compressibility has been used to improve the coupling of pressure and velocity in the framework of a finite volume approach. Time-averaged distributions of pressure fields, velocity components, streamlines in the entire area and near the tractor-trailer, as… More >

D. O. Redchyts¹, E. A. Shkvar^2,*, S. V. Moiseienko³

FDMP-Fluid Dynamics & Materials Processing, Vol.15, No.5, pp. 509-525, 2019, DOI:10.32604/fdmp.2019.08266

Abstract A mathematical model for unsteady electro- and aerodynamic processes in the presence of a plasma actuator has been elaborated through physical modeling of the dielectric barrier discharge. A specialized computational fluid dynamics package has been developed accordingly in order to calculate steady and unsteady laminar and turbulent flows. For the numerical simulation of the dielectric barrier discharge, in particular, two equations have been added to the Navier-Stokes equations and solved. They describe the distribution of the applied voltage and the charged particles density. The impact of the plasma actuator on air has been accounted for through the Lorentz force, included… More >

W. A. El-Askary, A. Abdel-Fattah

CMES-Computer Modeling in Engineering & Sciences, Vol.83, No.4, pp. 425-458, 2012, DOI:10.3970/cmes.2012.083.425

Abstract In the present paper, experimental and numerical studies of heat transfer and the frictional head loss of turbulent flow in a duct with a heated upper surface are performed. Four different arrangements are considered (case 1: without baffles, case 2: one perforated baffle on the upper wall and one solid baffle on the lower wall, case 3: one perforated baffle on the upper wall and one perforated baffle on the lower wall and case 4: two perforated baffles on the upper wall). A numerical code developed by the present authors is simultaneously presented including four different turbulence models; namely: the… More >