Begell House
Journal of Porous Media
Journal of Porous Media
1091-028X
18
9
2015
EXPERIMENTAL STUDY OF AIR COOLING USING A MEMBRANE-COVERED TRAY
An experimental study is conducted to cool the outdoor air using a new humidification technique. A wind tunnel is
built with a membrane-covered tray serving as a test section. Outdoor air passes over a tray full of water and covered by a specific membrane. Air temperature and relative humidity data are measured before and after the tray for several air velocities and for three different angles of the tray. Air velocity is measured at different locations along the centerline of the rectangular wind tunnel cross section before the tray. For almost fixed outdoor temperature before the test section,
results show that as the angle of the tray increases, the drop in air temperature increases, which improves the efficiency of the humidification technique. This enhancement is reflected by a maximum and minimum drop in air temperature of 13.05°C and 2.41°C, respectively. This maximum cooling is obtained using a 10°C tray angle orientation. Results also show in general that as the tray angle increases, the difference in the air relative humidity before and after the test section increases at high air velocities.
Mohamed
Ali
King Saud University, College of Engineering, Mechanical Engineering Department, P. O. Box 800, Riyadh 11421, Saudi Arabia
O.
Zeitoun
Mechanical Engineering Department, King Saud University, P.O. Box 800, Riyadh 11421, Saudi Arabia
H.
Al-Ansary
Department of Mechanical Engineering, King Saud University, Riyadh, Saudi Arabia
A.
Nuhait
Mechanical Engineering Department, King Saud University, P.O. Box 800, Riyadh 11421, Saudi Arabia
835-842
EFFECTS OF MICRO- AND MACRO-SCALE VISCOUS DISSIPATIONS WITH HEAT GENERATION AND LOCAL THERMAL NON-EQUILIBRIUM ON THERMAL DEVELOPING FORCED CONVECTION IN SATURATED POROUS MEDIA
This study reports the results of the numerical investigation of steady-state thermal developing forced convection between
parallel plate channels. The Darcy−Forchheimer−Brinkman model is used for momentum equation. Based on the
local thermal equilibrium taking into account the viscous dissipation and the heat generation in solid and fluid phases,
temperature profiles of the solid and fluid are obtained numerically in a saturated porous medium, with walls being at
constant temperature and constant heat flux. The temperature and the Nusselt number profiles are shown in figures for
different dimensionless fluid parameters such as Prantdl, Darcy, Forchheimer, and Brinkman number and the effects of
thermal parameters such as the dimensionless heat exchange coefficient, thermal conductivity ratio, fluid heat number
and solid heat numbers on the length, and the heat transfer of the thermal developing region are revealed by parameter
study. Furthermore, four terms contributing to the viscous dissipation are investigated and the comparisons between
the effects of combinations of these terms with temperature boundary conditions are highlighted.
M. Y. Abdollahzadeh
Jamalabadi
Ship Engineering Department, School of Mechanical Engineering, Chabhar Maritime University, Chabahar 99717-56499, Iran; Department of Mechanical Engineering, Gyeongsang National University, Jinju 770-601, South Korea
843-860
STUDIES ON PERMEABILITY PROPERTIES AND PARTICLE CAPTURE EFFICIENCIES OF POROUS SiC CERAMICS PROCESSED BY OXIDE BONDING TECHNIQUE
Porous SiC ceramics bonded with mullite [MBS of fractional porosity (ε) of 0.29-0.56, average pore size (dpore) of 5-11 μm, flexural strength (σ) of 9-34 MPa, and elastic modulus (E) of 7-28 GPa] and cordierite (CBS with ε of 0.33-0.72, dpore of 6-50 μm, σ of 5-54 MPa, and E of 6-42 GPa) were prepared by heating in air at 1350-1500°C compacts of desired amounts of SiC, Al2O3, and MgO powders and petroleum coke dust as the pore former. Air permeation behavior of well-characterized samples was studied with fluid superficial velocity (νs) from 0.08 to 1.0 m s−1 and at RT to 750°C. The Darcian (k1) and non-Darcian (k2) permeability coefficients were evaluated by fitting the Forchheimer's equation to experimental pressure drop-superficial velocity data. Porosity dependence of permeability coefficients was explained in
terms of structural characteristics. Changes in pressure drop experienced by the porous ceramics at high temperatures were explained by temperature dependence of permeability coefficients and variation of fluid properties. Collection efficiency (Eoverall) of filter ceramics operating on removal of solid NaCl nanoaerosol particles (of 7-300 nm size) was determined from particle counts before and after filtration at νs = 0.05-0.10 m s−1. Experimental results showed variation of Eoverall from 96.7 to 99.9% for change of ε from 0.56 to 0.68. The size-selective fractional collection efficiency at different porosity levels was derived using the well-known single-collector efficiency model considering some boundary conditions and the model data were validated with experimental results. The test results were used to
examine the applicability of the filter ceramics in nanoparticle aerosol filtration processes.
Atanu
Dey
Non-Oxide Ceramic Composite Division, Central Glass and Ceramic Research Institute, CSIR, Kolkata-700 032, West Bengal, India
Nijhuma
Kayal
Non-Oxide Ceramic Composite Division, Central Glass and Ceramic Research Institute, CSIR, Kolkata-700 032, West Bengal, India
Omprakash
Chakrabarti
Non-Oxide Ceramic Composite Division, Central Glass and Ceramic Research Institute, CSIR, Kolkata-700 032, West Bengal, India
Rafael F.
Caldato
Course of Chemical Engineering, University of Ribeirao Preto (UNAERP), 14096-900 Ribeirao Preto, SP, Brazil
Caio M.
Andre
Course of Chemical Engineering, University of Ribeirao Preto (UNAERP), 14096-900 Ribeirao Preto, SP, Brazil
Murilo D. M.
Innocentini
Course of Chemical Engineering, University of Ribeirao Preto (UNAERP), 14096-900 Ribeirao Preto, SP, Brazil
Vadila G.
Guerra
Department of Chemical Engineering, Federal University of Sao Carlos (UFSCar), 13565-905 Sao Carlos, SP, Brazil
861-872
FORCED CONVECTION IN A DARCY−BRINKMAN POROUS MEDIUM WITH A CONVECTIVE THERMAL BOUNDARY CONDITION
The heat transfer characteristics of the boundary layer flow past a plane surface adjacent to a saturated Darcy−Brinkman
porous medium are investigated in this paper. An external free stream moving at constant velocity drives the flow. A
convective boundary condition with a specified constant heat transfer coefficient is applied to the surface. The problem
can be characterized as non-similar and is investigated analytically, as well as numerically by a finite volume method.
It is found that the velocity field changes from two-dimensional to one-dimensional, where an analytical solution exists.
The governing non-dimensional parameters for the developed thermal field are the convective Darcy number, the Prandtl
number, and the axial distance along the plate. The influence of these parameters on the thermal field is investigated and
the results are presented in tables and figures. The temperature and wall heat transfer tend to an asymptotic state, where
analytical solutions exist.
Asterios
Pantokratoras
School of Engineering, Democritus University of Thrace, 67100 Xanthi, Greece
873-878
EFFECT OF ANGLE OF INCLINATION ON NONUNIFORM FLOW THROUGH POROUS MEDIA
Steady nonuniform flow through porous media was investigated when the porous media were confined within a convergent configuration. The objectives are to investigate how the velocity of fluid is affected when it flows through porous media of different porosities of varying angles of inclination and also to study the variation of resistance flow or friction factor (Fk) with varying angle of inclination and ratio of widths (B1/B2). In order to meet the objective of this study,
a tilting angle convergent permeameter was fabricated and crushed rock of size 7.30 mm was used as media and water
as fluid, to develop curves relating friction factor (Fk) and Reynolds number (Rk) for different ratios of width using intrinsic permeability (k) as characteristic length. The variation of Fk and Rk for different Cw values for different tilting angles (φ) are compared to the experimental data and observed to lie on the theoretical curve. It was inferred that angle
of inclination has a significant effect on the nonuniform flow, and it was noticed that velocity of flow increases with increasing angle of inclination and it was also observed that the greater the difference in the porosity of the cross section of the media in which the fluid is flowing, the greater the intrinsic permeability (k). Also observed was that both linear
parameter a and nonlinear parameter b increase with decrease of angle of inclination for different ratios of width. The variation of intrinsic permeability (k) and media constant (CW) with different tilting angles (φ) is examined and also is developed k versus N curves and CW versus B1/B2 curves for different tilting angles (φ). Experimental results show that resistance flow increases with the decrease of tilting angle and it was also observed that resistance flow increases
with the increase of ratio of widths (B1/B2).
N. Bhanu Prakasham
Reddy
Water Resources Department, GNSS Division, Renigunta @ Tirupati - 517501, Chittoor District, Andhra Pradesh State, India
S.
Krishnaiah
Department of Civil Engineering, J.N.T.U.A. College of Engineering, Anantapur - 515002, Andhra Pradesh State, India
M. Ramakrishna
Reddy
Department of Earth Science, Yogivemana University, Kadapa - 516004, Y.S.R. District, Andhra Pradesh State, India
879-892
ARTIFICIAL INTELLIGENCE BASED ESTIMATION OF WATER SATURATION IN COMPLEX RESERVOIR SYSTEMS
The effect of shale on the evaluation of water saturation in shaly porous media is yet to be fully understood.Wide varieties of water saturation models for shaly sands are currently in use. However, none is universally accepted by log analysts and each model estimates water saturation value significantly different from the others. Error in water saturation can result in either underestimation or overestimation of hydrocarbon reserves, which will influence management decision on a given field. A laboratory measurement of water saturation is the most accurate but limited by time and cost,
thereby forcing the industry to rely on these models. In this paper, we show how a computer artificial intelligence (AI)
system can predict water saturation with an accuracy of 93% compared to selected saturation models. Three saturation
models were selected and subjected to same well log data as the AI model to estimate water saturation. The estimated
saturation values for AI and other saturation models were then compared with experimental values for 147 core samples
and results showed that the AI model was able to use shale affected log data to accurately predict water saturation while
the saturation models did the same with lesser accuracy of 63, 50, and 43%. A statistical and graphical comparison of
accuracy and error between the AI technique and selected models is presented.
Abdulrauf R.
Adebayo
Center of Petroleum & Minerals, Research Institute, King Fahd University of Petroleum & Minerals, Dhahran, Saudi Arabia
Abdulazeez
Abdulraheem
Petroleum Engineering Department, King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia
Sunday O.
Olatunji
College of Computer Science & IT, University of Dammam, Dammam, Saudi Arabia
893-906
MULTIPLE SLIP EFFECTS ON UNSTEADY MAGNETOHYDRODYNAMIC NANOFLUID TRANSPORT WITH HEAT GENERATION/ABSORPTION EFFECTS IN TEMPERATURE DEPENDENT POROUS MEDIA
Transient hydromagnetic flow, heat, and mass transfer of a conducting nanofluid in a Darcian porous medium is
studied. The heat generation/absorption effect is incorporated based on the dual formulation of Tsai et al. (Tsai, R.,
Huang, K. H., and Huang, J. S., Flow and Heat Transfer over an Unsteady Stretching Surface with Non-Uniform
Heat Source, Int. Commun. Heat Mass Transfer, vol. 35, pp. 1340-1343, 2008), for space and temperature dependence.
Multiple slip phenomena are also featured in the model to simulate certain industrial polymer flows where the no-slip
wall boundary condition is violated. A 2D unsteady incompressible boundary layer model is developed for water based
nanofluid containing two different types of nanoparticles, namely alumina and copper nanoparticles. The resulting
partial differential equations with corresponding boundary conditions are rendered into a system of coupled ordinary
differential equations via suitable similarity transformations. The nonlinear boundary value problem is then solved with
Maple quadrature. Validation of solutions is achieved with previous studies for selected values of Prandtl number and
temperature-dependent heat generation/absorption parameter, demonstrating very good correlation. The influence of
Richardson number, buoyancy ratio parameter, nanoparticle solid volume fraction, magneto-hydrodynamic body force
parameter, Darcy number, unsteadiness parameter, wall transpiration (suction/injection parameter), velocity slip parameter,
thermal slip parameter, mass slip parameter, space- and temperature-dependent heat source/sink parameter on
velocity, temperature, and concentration distributions are examined. Furthermore the effects of these parameters on skin
friction, Nusselt number, and Sherwood number are also analyzed. The present simulations are relevant to magnetohydrodynamic
energy devices exploiting nanofluids.
Osman Anwar
Beg
Gort Engovation-Aerospace, Medical and Energy Engineering, Gabriel's Wing House, 15
Southmere Avenue, Bradford, BD73NU, United Kingdom
Waqar A.
Khan
Department of Mechanical Engineering, University of Waterloo, Waterloo, Ontario, N2L 3G1 Canada
Mohammed Jashim
Uddin
School of Mathematical Sciences, Universiti Sains Malaysia, Penang 11800, Malaysia; Department of Mathematics, American International University-Bangladesh, Banani, Dhaka 1213, Bangladesh
907-922
MAGNETOHYDRODYNAMIC FLOW IN A CIRCULAR CHANNEL FILLED WITH A POROUS MEDIUM
Steady flow of an electrically conducting viscous incompressible fluid in a circular channel filled with a saturated
porous medium in the presence of transverse magnetic field is considered. The Brinkman equation is used for flow in
porous media. The exact solutions for velocity, average velocity, rate of volume flow, and shear stress on the boundary
are obtained and exhibited graphically. Influence of various parameters such as Hartmann number and permeability
parameter on the flow are discussed.
Vineet Kumar
Verma
Department of Mathematics and Astronomy University of Lucknow, Lucknow, INDIA-226007
Sanjeeva Kumar
Singh
Department of Mathematics and Astronomy University of Lucknow, Lucknow, INDIA-226007
923-928