J. Serrano-Arellano¹, J. M. Belman-Flores^2,*, I. Hernández-Pérez³, K. M. Aguilar-Castro³, E. V. Macías-Melo³, F. Elizalde-Blancas², J. M. Riesco-Ávila², F. J. García-Rodríguez⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.123, No.2, pp. 571-602, 2020, DOI:10.32604/cmes.2020.08677 - 01 May 2020

Abstract In the present study, an analysis of the heat and mass transfer in a ventilated cavity in a warm climate zone was carried out to analyze, among others, the temperatures and percentage of relative humidity (RH). The governing equations of the mathematical model were solved through the finite volume method. We used the k-ε turbulence mode to find the results of the variables of interest in seven climate records on a given day. The velocity of the inlet flow of the air-H₂O mixture was varied through the Reynolds number (Re) from 500 to 10000. The outdoor weather… More >

Weiyu Zhang^a , Mo Yang^a,*, Yuwen Zhang^b

Frontiers in Heat and Mass Transfer, Vol.12, pp. 1-8, 2019, DOI:10.5098/hmt.12.18

Abstract The periodically fully-developed flow and heat transfer in channels with periodic semi-circular tube is studied numerically by the direct numerical simulation (DNS), the large eddy simulation (LES), and the Reynolds stress model (RSM). When the Reynolds number is between 3000 and 25000, the Nusselt number obtained by the RSM is closer to the experimental results than the results obtained from other turbulence models. The nonlinear characteristics of flow and heat transfer is revealed based on the results of numerical simulation. When Reynolds number is high, the geometric structure and boundary conditions of the channel are More >

Wen Zhao, Dongxing Mao^*, Zaixiu Jiang

Sound & Vibration, Vol.53, No.1, pp. 37-46, 2019, DOI:10.32604/sv.2019.04368

Abstract In order to analyze the effect of the background flow on the sound prediction of fine-scale turbulence noise, the sound spectra from static and flow environments are compared. It turns out that, the two methods can obtain similar predictions not only at 90 deg to the jet axis but also at mid- and high frequencies in other directions. The discrepancies of predictions from the two environments show that the effect of the jet flow on the sound propagation is related to low frequencies in the downstream and upstream directions. It is noted that there is More >

Rama Govindarajan¹, S. Ravichandran², Jason Picardo¹, Samriddhi Sankar Ray¹, S. Ganga Prasath¹, Vishal Vasan¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.22, No.4, pp. 194-194, 2019, DOI:10.32604/icces.2019.05206

Abstract A cloud is in turbulent motion. It contains water vapour, aerosol particles and liquid water droplets. Depending on local levels of supersaturation, condensation takes place onto the aerosol particles and tiny droplets are formed. Our studies are aimed at understanding how these droplets grow in a short time, thought to be of the order of ten minutes, from about a micron in size into raindrops, which are of the order of millimeters. An important part of the process is collisions between droplets, some of which results in coalescence. Caustics from a single vortex are shown… More >

Fatiha Bentarzi¹, Amina Mataoui^{1, *}

FDMP-Fluid Dynamics & Materials Processing, Vol.14, No.2, pp. 107-120, 2018, DOI:10.3970/fdmp.2018.06046

Abstract The dynamics of two fully developed turbulent jets, perpendicular to a heated flat plate and related heat transfer mechanism are analysed numerically. This problem is relevant to several thermal engineering applications. The governing equations are solved by a finite volume method with a second order RSM model combined with wall functions used for turbulent modelling. The possibility to improve heat transfer is assessed taking into account the characteristic parameters for the jet-wall interaction. In particular, a parametric study is conducted by varying the jet Reynolds number (Re) and the nozzle to plate distance (D). The… More >

M.M.R. Damasceno¹, J.M. Vedovoto¹, A. da Silveira-Neto¹

CMES-Computer Modeling in Engineering & Sciences, Vol.104, No.2, pp. 105-132, 2015, DOI:10.3970/cmes.2015.104.105

Abstract Turbulence is a phenomenon which presents peculiarities when it is experimented or simulated. This occurs due to its complexity and high sensibility to the inlet conditions of the turbulent flow fields, as well as the presence of a large range of time and length scales. A simplification for this situation is obtained with the use of approximations and turbulence models. In the present work, the Largeeddy Simulations methodology was applied, aiming the modeling of the previously mentioned complexity, which consists in using a filter to resolve the large scales while the remaining scales were determined More >

Nadjib Ghiti¹

CMES-Computer Modeling in Engineering & Sciences, Vol.99, No.3, pp. 195-208, 2014, DOI:10.3970/cmes.2014.099.195

Abstract This paper presents a large eddy simulation of three dimensional vertically impinging jet on a horizontal plate. The air impinging jet was simulated using the perturbed method based on a high vortex number in the jet inlet for different ranges of Reynolds number Re= 6000, 8000, 10000, 12000, 14000 and for the same distance between the jet and the impinging plate. The effect of the Reynolds number of the air jet impinging on a horizontal plate was studied; the study showed that the vorticity magnitude is increased with the increasing of the Reynolds number. The More >

F. Iachachene¹, A. Matoui², Y. Halouane¹

FDMP-Fluid Dynamics & Materials Processing, Vol.10, No.4, pp. 503-520, 2014, DOI:10.3970/fdmp.2014.010.503

Abstract Computations related to a heat transfer and fluid flow of a plane isothermal fully developed turbulent plane jet flowing into a rectangular hot cavity are reported in this paper. Both velocity and temperature distributions are computed by solving the two-dimensional Unsteady Reynolds Averaged Navier--Stokes (URANS) equations. This approach relies on one point statistical modeling based on the energy - specific dissipation (k-ω) turbulence model. The numerical simulations are carried out in the framework of a finite volume method. This problem is relevant to a wide range of practical applications including forced convection and the ventilation of More >

A. Balabel^1,2,3, W. A. El-askary², S. Wilson²

CMES-Computer Modeling in Engineering & Sciences, Vol.95, No.6, pp. 483-499, 2013, DOI:10.3970/cmes.2013.095.483

Abstract In the present paper, the impingement of air jet on a heated flat plate subjected to a periodic oscillation is numerically and experimentally investigated. The motivation of the present research is the desire to enhance the heat transfer characteristics during the cooling process of a heated flat plate which can be found in many relevance industrial applications. In order to improve the heat transfer characteristics, a novel idea is utilized, where a periodical oscillation movement in form of sine wave produced from a Scotch yoke mechanism is applied to the heated flat plate. The obtained More >

Ashraf Balabel¹

CMES-Computer Modeling in Engineering & Sciences, Vol.95, No.4, pp. 283-302, 2013, DOI:10.3970/cmes.2013.095.283

Abstract This paper presents the numerical results obtained from the numerical simulation of turbulent liquid jet atomization due to three distinctly different types of liquid jets/air orientations; namely, coflow jet, coaxial jet and the combined coflow-coaxial jet. The applied numerical method, developed by the present authors, is based on the solution of the Reynolds-Averaged Navier Stokes (RANS) equations for time-dependent, axisymmetric and incompressible two-phase flow in both phases separately and on regular and structured cell-centered collocated grids using the control volume approach. The transition from one phase to another is performed through a consistent balance of… More >