Begell House Inc.
Journal of Porous Media
JPM
1091-028X
19
12
2016
EXPERIMENTAL INVESTIGATION OF NATURAL CONVECTION FROM POROUS BLOCKS IN A CAVITY
1023-1032
10.1615/JPorMedia.v19.i12.10
Ayla
Dogan
Department of Mechanical Engineering, Faculty of Engineering, Akdeniz University TR-07058, Antalya, Turkey
O.
Ozbalci
Department of Mechanical Engineering, Faculty of Engineering, Akdeniz University TR-07058, Antalya, Turkey
I.
Atmaca
Department of Mechanical Engineering, Faculty of Engineering, Akdeniz University TR-07058, Antalya, Turkey
natural convection
aluminum foam blocks
electronic
Natural convection heat transfer from aluminum (Al-6101) foam blocks with different pore densities (10, 20, and 40 pore per inch (PPI)) were investigated experimentally. Air was used as the working fluid. The test section was equipped with 3 × 3 aluminum foam blocks placed on copper plates and subjected to a uniform heat flux. The modified Rayleigh number Ra* varied between 8.33 × 105 and 5.24 × 106, while the foam height varied between 10 and 30 mm. The effects of block height and pore density of the aluminum foam on the heat transfer enhancement were determined. For the highest Rayleigh number, the results show that the thermal performance of the aluminum foam having H = 30 mm average Nusselt number obtained for pore density of 40 PPI is about 1.5 and 1.36 times higher than for 10 PPI and 20 PPI, respectively, and also 3.85 times higher than without a foam case in a cavity.
NON-DARCY EFFECTS ON THREE-DIMENSIONAL NATURAL CONVECTION IN A RECTANGULAR BOX CONTAINING A HEAT-GENERATING POROUS MEDIUM
1033-1043
10.1615/JPorMedia.v19.i12.20
Anil Kumar
Mishra
Research Scholar, Department of Mechanical Engineering, NIT Jamshedpur, India
S.
Kumar
Department of Mechanical Engineering, NIT Jamshedpur, India
Ram Vinoy
Sharma
Department of Mechanical Engineering, National Institute of Technology Jamshedpur, Jharkhand, India
natural convection
porous media
internal heat generation
numerical study
The present numerical study reports results of three-dimensional natural convection in a rectangular box filled with a fluid-saturated heat-generating porous medium. The Brinkman−extended Darcy flow model is considered in this study. The model has been numerically simulated employing a successive accelerated replacement scheme for a wide range of parameters, that is, 100 ≤ Ra ≤ 10, 0.00001 ≤ Da ≤ 0.1, 0.1 ≤ Ay ≤ 10, and 0.1 ≤ Az ≤ 10. As Darcy number increases, maximum temperature increases and position of maximum temperature shifts downward toward the center. The effect of varying the Darcy number is more pronounced at higher Rayleigh numbers and higher aspect ratios.
EVAPORATION OF FALLING LIQUID FILM ON A VERTICAL CHANNEL COVERED WITH A THIN POROUS LAYER
1045-1060
10.1615/JPorMedia.v19.i12.30
Abdelaziz
Nasr
Laboratory of Thermal and Energy Systems Studies, Monastir University, 5019 Monastir, Tunisia; Mechanical Engineering Department, College of Engineering, Umm Al-Qura University, Makkah, Saudi Arabia
Abdulmajeed Saeed
Al-Ghamdi
Mechanical Engineering Department, College of Engineering, Umm Al-Qura University, Makkah, Saudi Arabia
liquid film evaporation
heat and mass transfer
porous medium
mixed convection
This article investigates the numerical analysis of heat and mass transfer during the evaporation of water liquid film. The film falls down on one plate of a vertical channel under mixed convection. The first plate of a vertical channel is covered with a thin porous layer of thickness δ and externally subjected to a uniform heated flux qi while the second one (y = d) is dry and isothermal. The liquid consists of pure water film while the gas mixture has two components: dry air and water vapor. The results address the effects of porosity £ and porous layer thickness 5 of the porous media on the heat and mass transfer performance and on the water evaporation rate. It is shown that the presence of the porous layer enhances the heat and mass transfer performance at the liquid−gas interface during the water liquid film evaporation.
CHARACTERIZATION OF GAS/GAS CONDENSATE RESERVOIRS BY DECONVOLUTION OF MULTIRATE WELL TEST DATA
1061-1081
10.1615/JPorMedia.v19.i12.40
Behzad
Vaferi
Department of Chemical Engineering, Shiraz Branch, Islamic Azad University, Shiraz, Iran; Department of Advanced Calculations, Chemical, Petroleum, and Polymer Engineering Research
Center, Shiraz Branch, Islamic Azad University, Shiraz, Iran
Reza
Eslamloueyan
School of Chemical and Petroleum Engineering, Shiraz University, Shiraz, Iran
gas/gas condensate reservoir
multirate well test data
pseudo-pressure
deconvolution
reservoir characterization
Analyzing multirate well test data may not he achieved using conventional methods. Deconvolution reconstructs a unit step response (USR) over a radius of investigation of the multirate well test data and can provide more information than the conventional method. We propose a workflow for characterizing gas/gas condensate reservoirs from multirate well test data. It comprises five steps: (1) linearization of pressure transient signals of both gas and gas condensate reservoirs using pseudo-pressure; (2) extraction of USR of the linearized signals by deconvolution; (3) calculation of the log-log derivative graph of the extracted USR; (4) detection of wellbore, reservoir, and boundary models from the log-log derivative plot; and (5) estimation of wellbore, reservoir, and boundary parameters using their associated flow regimes. The methodology is validated by synthetic well test signals of a gas reservoir and two different gas condensate reservoirs. Results confirm that this technique can correctly detect wellbore, reservoir, and boundary models of all data. Also, the proposed method presents average relative deviations (ARDs) in the range of 0.18%−1% for wellbore storage, 0.01%−1.3% for permeability, 0.11%−3.78% for skin factor, 1%−10% for non-Darcy skin, and 0.11%−0.26% for boundary distance.
EFFECT OF QUADRATIC DENSITY VARIATION ON MIXED CONVECTION STAGNATION POINT HEAT TRANSFER AND MHD FLUID FLOW IN POROUS MEDIUM TOWARDS A PERMEABLE SHRINKING SHEET
1083-1097
10.1615/JPorMedia.v19.i12.50
Rakesh
Kumar
Department of Mathematics, Central University of Himachal Pradesh, Dharamshala, India
Shilpa
Sood
Department of Mathematics, Central University of Himachal Pradesh, TAB, Shahpur, Kangra, Himachal Pradesh 176206, India
quadratic density temperature variation
stagnation point flow
permeable shrinking sheet
porous medium
magnetic field
dual solutions
This investigation deals with the analysis of stagnation point heat transfer and corresponding flow features of hydromagnetic viscous incompressible fluid over a vertical shrinking sheet. The considered sheet is assumed to be permeable and subject to addition of stagnation point to control the generated vorticity in the boundary layer. The sheet is placed on the right side of the fluid-saturated porous medium, which has permeability of specified form. Nonlinear convection waves in the flow field are realized due to the envisaged nonlinear relation between density and temperature. The equations governing the quadratic density dependence convection boundary layer flow are modeled and simplified using similarity transformations. The economized equations are solved for numerical solutions by employing the implicit finite difference scheme, also known as the Keller-box method. The influence of the associated parameters of the problem on velocity and temperature distributions, skin friction, and rate of heat transfer are presented through graphs and tables and qualitatively discussed. The study reveals that interaction among magnetic field, porous medium permeability, and quadratic density temperature parameters substantially enhances the solution range and thus endorses their control to sustain the boundary layer flow.
NUMERICAL STUDY OF PHASE CHANGE CHARACTERISTICS IN A VERTICAL AND INCLINED POROUS CHANNEL USING THERMAL NONEQUILIBRIUM MODEL
1099-1121
10.1615/JPorMedia.v19.i12.60
Mohammed
Nima
Faculaty of Mechanical Engineering Department
porous media
mixed convection
phase change
thermal nonequilibrium model
vertical and inclined channel
The problem of mixed convection boiling heat transfer in a vertical and inclined square porous channel packed with copper beads is numerically investigated by using a thermal nonequilibrium model with water as the working fluid. The square porous channel is subjected to a constant heat flux from the right wall, while the left wall is assumed to be insulated. The influence of heat flux, particle sizes, inlet velocity, and inclination angle variation on both solid-phase and liquid-phase behavior is analyzed and presented. Results show that the liquid saturation decreased as the heat flux increased and reached its minimum value at the exit of the heated wall. The variation of local and mean heat transfer coefficient is also studied, and the results show that the variation of packed bead size caused a reduction in the local and mean heat transfer values for larger bead diameters. It was found that the orientation angle variation from the vertical position to the inclined position results in a gravity-induced mass flux that has a significant effect on the formation and spread of the two-phase zone in the porous channel and thus on the local and mean heat transfer coefficient values.
INDEX VOLUME 19, 2016
1123-1133
10.1615/JPorMedia.v19.i12.70