International Review of Mechanical Engineering

(IREME)

Contents:

The Assessment of the in-Cylinder Pressure by Means of the Morpho-Dynamical Vibration Analysis - Methodology and Application by A. Amoresano, V. Avagliano, V. Niola, G. Quaremba

999

A Statistical Method to Identify the Main Parameters Characterizing a Pressure Swirl Spray by A. Amoresano, G. Langella, V. Niola, G. Quaremba

1007

A Perspective Method for the Identification of the Transverse and Longitudinal Residual Internal Stress in Aluminium T-Joint FSW. First Evidences by A. Amoresano, V. Avagliano, V. Niola, G. Quaremba

1014

Double Diffusive Natural Convection in Non-Darcy Porous Media with Non-Uniform Porosity by Mohammed Sammouda, Kamal Gueraoui, Mohamed Driouich, Abdelhak Ghouli, Abdelhak Dhiri

1021

Investigation of the Flow Characteristics in a Sink-Swirl Flow within Two Disks by Ali M. Jawarneh

1031

Enhancement of Algorithm and Investigation of Heat Transfer Through Fins by Md. Moslemuddin Fakir, Sabira Khatun, S. B. Basri

1037

A Comparative Study of Two Mechanical Agitated System in Case of Non-Newtonian Fluids by L. Rahmani, , B. Draoui, , E. Benachour, , B. Mebarki, Oussama Seghier

1044

Influence of Cross Sectional Shape on the Heat Transfer Characteristics of Ladder Type Micro Channel Heat Sinks for ULSI by R. Brinda, R. Joseph Daniel, K. Sumangala

1053

Unsteady Flow Produced by Oscillations of Two Rotating Coaxial Disks by H. Volkan Ersoy

1062

Optimization of a Refrigerant Base Nanofluid-Cooled Microchannel Heat Sink with Pumping Power Consideration by Ahmed M. Adham

1069

CFD Study on Heat Transfer to Bingham Fluid During with Gate Impeller by L. Rahmani, , B. Draoui, , M. Bouanini, E. Benachour

1074

Numerical Study of the Effect of Interrupted Fins on the Effectiveness of Cross-Flow Heat Exchanger by Hassene Djemel, Mounir Baccar, Mohamed Mseddi

1080

(continued on inside back cover)

ISSN 1970-8734Vol. 7 N. 6

September 2013

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International Review of Mechanical Engineering (IREME)

Editorial Board:

Jeongmin Ahn (U.S.A.) Marta Kurutz (Hungary)

Jan Awrejcewicz (Poland) Herbert A. Mang (Austria)

Ali Cemal Benim (Germany) Josua P. Meyer (South Africa) Stjepan Bogdan (Croatia) Bijan Mohammadi (France)

Andrè Bontemps (France) Hans Müller-Steinhagen (Germany)

Felix Chernousko (Russia) Eugenio Oñate (Spain) Kim Choon Ng (Singapore) Pradipta Kumar Panigrahi (India)

Horacio Espinosa (U.S.A) Constantine Rakopoulos (Greece)

Izhak Etsion (Israel) Raul Suarez (Spain) Michael I. Friswell (U.K.) David J. Timoney (Ireland)

Nesreen Ghaddar (Lebanon) George Tsatsaronis (Germany)

Adriana Greco (Italy) Alain Vautrin (France) Carl T. Herakovich (U.S.A.) Hiroshi Yabuno (Japan)

David Hui (U.S.A.) Tim S. Zhao (Hong Kong)

Heuy-Dong Kim (Korea)

The International Review of Mechanical Engineering (IREME) is a publication of the Praise Worthy Prize S.r.l.. The Review is published bimonthly, appearing on the last day of January, March, May, July, September, November. Published and Printed in Italy by Praise Worthy Prize S.r.l., Naples, September 30, 2013. Copyright © 2013 Praise Worthy Prize S.r.l. - All rights reserved. This journal and the individual contributions contained in it are protected under copyright by Praise Worthy Prize S.r.l. and the following terms and conditions apply to their use: Single photocopies of single articles may be made for personal use as allowed by national copyright laws. Permission of the Publisher and payment of a fee is required for all other photocopying, including multiple or systematic copying, copying for advertising or promotional purposes, resale and all forms of document delivery. Permission may be sought directly from Praise Worthy Prize S.r.l. at the e-mail address: administration@praiseworthyprize.com Permission of the Publisher is required to store or use electronically any material contained in this journal, including any article or part of an article. Except as outlined above, no part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without prior written permission of the Publisher. E-mail address permission request: administration@praiseworthyprize.com Responsibility for the contents rests upon the authors and not upon the Praise Worthy Prize S.r.l.. Statement and opinions expressed in the articles and communications are those of the individual contributors and not the statements and opinions of Praise Worthy Prize S.r.l.. Praise Worthy Prize S.r.l. assumes no responsibility or liability for any damage or injury to persons or property arising out of the use of any materials, instructions, methods or ideas contained herein. Praise Worthy Prize S.r.l. expressly disclaims any implied warranties of merchantability or fitness for a particular purpose. If expert assistance is required, the service of a competent professional person should be sought.

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International Review of Mechanical Engineering (I.RE.M.E.), Vol. 7, N. 6

ISSN 1970 - 8734 September 2013

Manuscript received and revised August 2013, accepted September 2013 Copyright © 2013 Praise Worthy Prize S.r.l. - All rights reserved

1031

Investigation of the Flow Characteristics in a Sink-Swirl Flow within Two Disks

Ali M. Jawarneh Abstract – Flow characteristics in a sink-swirl flow within two disks are examined experimentally and numerically. The experiments and the predictions have been carried out for three bulk Reynolds numbers and four contraction ratios. Results show that as the contraction ratio and the Reynolds number increase, the pressure coefficient increases. Stronger vortices will be produced resulting in a higher tangential velocity and hence a higher pressure drop. The radial pressure decreases slowly from the inlet periphery up to halfway along the disk and then decreases sharply as the flow approach the exit hole. Air enters through the peripheral gap between the two disks and converges to the center where it discharges axially through the exit hole. This indicates that the flow moved towards a more favorable pressure gradient, hence the vortex flow accelerated according to the angular momentum conservation. It can be seen that the Reynolds stress model gives good agreement with the present experimental data and the percentage difference error between the predicted and experiments is less than 10%. Copyright © 2013 Praise Worthy Prize S.r.l. - All rights reserved. Keywords: Contraction Ratio, Two Disks, Sink-Swirl Flow, CFD, Vortex Generator

Nomenclature

inA Total inlet area

pC Pressure coefficient ( 22 inp / q )

inD Diameter of the inlet port

oD Disk diameter H Gap height p Static pressure

inp Static pressure at the inlet

outp Static pressure at the outlet

inQ Inlet volumetric flow rate r , ,z Radial, tangential and axial coordinate

respectively r Normalized radius ( or / r )

er Radius of the exit port

or Radius of the disk

eR Reynolds number ( e inR H U / ) S Inlet swirl ratio ( in inV / U )

i j ku ,u ,u Velocity components in Cartesian coordinates

rV ,V Mean tangential and radial velocity components

inq Total velocity vector at the inlet

inV Inlet tangential velocity component

inU Inlet radial velocity component

Greek Symbols Contraction ratio ( o er / r )

p Static pressure difference ( in aP P )

Radial pressure (

2

2 1

in

p r p r

q

)

Turbulence dissipation rate k Turbulent kinetic energy Inlet angle

I. Introduction The flow between two disks has received much

attention due to its significant relevance to many practical applications in many areas, such as turbo-machinery, heat exchangers, double disc valves, bearings, squeeze film dampers, face seals, viscometer, and power transmission systems. In all confined vortex applications, it is important to understand adequately the overall flow field evolution as a function of both the geometrical and flow parameters. A good knowledge of these flows will improve the design and performance of a variety of vortex devices.

Most of research deals with the flow over a rotating disk (Vatistas [1]), between a stationary and a rotating disk (Ozar et al. [2]), both disks rotate (Gauthier et al. [3]), between two stationary disks with pure radial flow (Vatistas et al. [4]). Little works deal with inlet swirl flow between two stationary disks. DeSantis and

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1032

Rakowsky[5] demonstrated experimentally the flow features in a sink flow within two discs, the radial and tangential velocity profiles were obtained using hot-wire anemometry. The swirling flow within a short vortex chamber with a small gap has been investigated analytically by Kwok et al [6]. Their results show that the values of apparent viscosity affect the velocity profiles within the vortex chamber. Savino and Keshock[7] investigated the swirling flow properties experimentally between a flat cylindrical chamber.

They observed that the magnitude of radial and tangential velocities increases as the disc radius decreases. In addition, they showed a depression in radial profiles around the mid gap. Singh et al. [8] have studied the problem for inward flow between two stationary parallel disks. The experimental study involves the measurement of velocity field with laser Doppler anemometry and the mean governing equations have been solved numerically using -model.

They concluded that the velocity and pressure predicted numerically are close to experimental data. Murphy et al. [9] studied the inward flow numerically. They showed three distinguish regions, a region of strong viscous effect, a region where the viscous effect and inertia effect are equal and a region of strong inertial effect. Reynolds stress models have greater potential to represent turbulent flow phenomena more correctly than the two-equation models especially for swirling flow (Ferziger and Peric[10]). The main complexity in numerical modeling of complex turbulent swirling flows is the selection of suitable turbulence closure models. In simple flow cases the -model performs well. However, it may be failed for strongly swirling flows that involves rigorous streamline bending. The last conclusion is clearly evident in a variety of studies; see for example the work of Nallasamy [11], Nejadet al. [12] and Weber [13].A review of second-moment computations for engineering flows has been provided by Launder [14], and Leschziner [15].

The results of these computations demonstrate the power of RSM over eddy-viscosity models for swirling flows. German and Mahmud [16] have shown that the overall agreement between the measurements and the predictions obtained with both -and Reynolds-stress turbulence models are reasonably good. However, some features of the isothermal and combusting flow fields are better predicted by the Reynolds-stress model. Jones and Pascau [17] and Hoekstra etal. [18] used the - turbulent model and a Reynolds stress transport equation model of a strong confined swirling flow. Jakirlic et al. [19] has shown numerically using three versions of the second-momentum closure and two eddy-viscosity models that the second-momentum models are superior.

However, difficulties in predicting accurately the transformation from free- to forced-vortex modes or the determination of the normal stress components inside the core still remain. Jones et al [20] have studied the performance of second moment closure turbulence models for swirling flow in a cylindrical combustion

chamber. The models are found to predict mean and turbulent flow quantities well.

Once more, comparisons of the results with measurements show the superiority of the transport equation model, where - gave some discrepancies between the measured and predicted velocity fields.Jawarnehet al. [21] have shown experimentally that the pressure drop in a sink-swirl flow within two disks to be a function of the Reynolds number and the inlet flow angle and the corresponding test data collapse into a single curve. Vatistaset al. [22] demonstrated experimentally the flow features in a sink-swirl flow within two discs. The radial profile of the static pressure was shown to depend on the relative vortex strength and the Reynolds number. Turbulent sink flow developing between two stationary disks under the influence of strong swirl was numerically investigated using the Reynolds stress model by Vatistaset al [23]. The last recent work has explained the appearance of a toroidal recirculation zone in the central flow region, the saddle-like behavior of the tangential velocity, and the two radial velocity kinks near the two end plates. Nevertheless, their result was limited to a specific contraction ratio. Up to our knowledge this is the first study which shows the effect of contraction ratio on pressure drop in a sink-swirl-flow where the previous studies focusedonly on a single contraction ratio. Scientists may expect the effect of contraction ratio hypothetically but this work will emphasize in that effect experimentally and numerically and this may be the burly value of the present work. Moreover, most of literatures attentive on inward-sink flow between two disks and many efforts have been done to find experimental data on swirl-sink flow to compare the present experimental data with literature, but no clue.

The purpose of the present work is to study the pressure drop and the radial pressure in a sink-swirl flow within two disks at different contraction ratio (defined here as the disk diameter / exit diameter ratio) experimentally and numerically. The Reynolds stress model RSM is implemented in CFD code developed by Fluent 6.2 (Fluent Inc.), which is based on finite volume method.

II. Experimental Set-Up The present experiments as shown in Fig. 1 have been

conducted using a jet-driven swirl generator similar to the one utilized by Jawarnehet al. [21]. It consists of two stationary parallel disks of radius ro= 381 mm with a gap height H = 12.7 mm as shown in Fig. 2. The two disks were fabricated from Plexiglas. The upper disk with a concentric hole was connected to a suction compressor.

The exit area is adjusted by replacing hole-plates with four different exit radius re of 15.875, 13.335, 11.113 and 7.938 mm, which are corresponding to four contraction ratios = ro/re: 24, 28, 34, and 48 respectively. The swirl generator, see Fig. 3, with an inlet angle =300 was used for the present experiments.

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Fig. 1. Schematic of the physical problem herein investigated

Fig. 2. Schematic of experimental set-up

Fig. 3. Swirl generator The aluminum vortex generator ring was used to

introduce swirl through the two disks. It had an outer diameter of 762 mm, an inner diameter of 610 mm and a thickness of 12.7 mm. When air is sucked through the swirl generator, in addition to the radial velocity, it also develops a tangential component that depends on the value of the inlet angle.

The generator had 48 inclined holes with diameter Din = 6.35 mm, hence the total inlet area (Ain) is equal to 1.52×10-3 m2.

Measurements were made at three inlet air flow rates Qin of 0.0187, 0.0141, and 0.0094 (m3/s) which are corresponding to three bulk Reynolds numbers (Re=HUin/) of 5172, 3900, and 2598 respectively, where Uin is the inlet radial velocity, and the kinematic viscosity. In order to obtain accurate measurements, a sensitive inclined manometer was used to measure the static pressure along the radius. The manometer contains Meriam oil with specific gravity equal to 1.

The measurements of static pressure along the radius were obtained using 12 static pressure taps, in addition the measurements of the mean gage pressure difference pout-pin were obtained, where pout and pin are the static pressure at the outlet and inlet respectively.

The estimated uncertainty for the static pressure measurements was done by repeating the individual readings of the static pressure five times, finding the average, and then for small sets of data an unbiased or sample standard deviation was implemented.

The estimated uncertainty is less than 8% for the static pressure measurements.

Air at standard temperature was the working fluid. The volumetric flow rate was recorded using a calibrated variable area rotameter which was located between the outlet of the experimental apparatus and the inlet (suction) of the compressor. This was carefully calibrated in standard conditions (1 atmosphere and 20 0 5. % °C).

For the flow rate used, the uncertainty was estimated to be 2% .

III. Computational Details The continuity and momentum equations can be

written in tensor form as:

0i

iu

x

(1)

23

i jj i

ji lij

j j i l

i jj

Pu ux x

uu ux x x x

u ux

(2)

The Reynolds stress model RSM (Launder et al.,

[24]) involves calculation of the individual Reynolds stresses, i ju u , using differential transport equations.

The individual Reynolds stresses are then used to obtain closure of the Reynolds-averaged momentum Eq. (2).

The transport equations for the transport of the Reynolds stresses, i ju u , can be written as follows:

Ø 610 mm Ø 762 mm

Uin Vin

qin

Inlet Pressure Tap

φ

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23

ij

ij

i jtk i j

k k k kC

i jk k

j ii k j k

k k

P

ij ij

u uu u u

x x x

u ux x

u uu u u u

x x

(3)

The term on the left-hand side of this equation

represents the convection, the terms on the right-hand side represent the turbulent diffusion as proposed by Lien and Leschziner [25], molecular diffusion, stress production, pressure strain and the dissipation respectively. The pressure strain term ij is simplified according to the proposal by Gibson and Launder [26].

The dissipation rate, , is computed with a model transport equation as:

1

2

2

12

ti ii

i j ju C P

x x x k

Ck

(4)

where 1 0k . , 1 1 44C . , and 2 1 92C . are constants taken from Launder and Spalding [27]. Due to rigorous pressure gradients, the non-equilibrium wall functions were used near wall as proposed by Kim and Choudhury [28].

Inlet boundaries for k and : The turbulence intensity I can be estimated from the following formula:

in

uIU

(5)

The turbulence length scale l is a physical quantity

related to the size of the large eddies that contain the energy in turbulent flows. An approximate relationship between l and the physical size of the disk diameter oD is:

0 07 ol . D (6)

The relationship between the turbulent kinetic energyk , and turbulence intensity I , is:

23

2 ink U I (7)

where inU is the inlet radial velocity. The turbulence dissipation rate can be determined as:

3 23 4

// kC

l (8)

IV. Solution Procedure The governing differential equations for mass,

momentum, turbulent kinetic energy and its dissipation rate were solved using the control-volume-based finite difference method.

The problem here is considered to be incompressible, steady, axisymmetric, turbulent swirling flows. In this case, we can model the flow in 2D (i.e., solve the axisymmetric swirl problem) and incorporate the prediction of the swirl velocity, see Fig. 4.

Fig. 4. Computational domain The difficulties associated with the solution of

strongly swirling flows can be attributed to high degree of coupling in the momentum equations. High fluid rotation gives rise to large radial pressure gradient which drives the flow in the meridional plane. This, in turn, determines the distribution of the swirl in the field.

Hence, segregated, implicit solver, which is well-suited for the sharp pressure and velocity gradients are more appropriate for the flow under consideration. The mesh is sufficiently refined in order to resolve the expected large flow parameter gradients. The under-relaxation parameters on the velocities were selected 0.3-0.5 for the radial and 0.9 for the swirl velocity components.

There is a significant amount of swirl between the two disks. The proper choice depends on the strength of the inlet flow components. To characterize the degree of swirling flow, the inlet swirl ratio S is defined as:

in

in

VS

U (9)

where inV and inU are the inlet radial and tangential velocity components. Then, the simulations were performed for inlet swirl ratio equal to 1.73. The convective and diffusive terms were discretized using power law scheme and the SIMPLER algorithm [29] was used to resolve the pressure-velocity coupling.

For all the simulations performed in this study, converged solutions were usually achieved with residuals as low as 10-6 for all governing equations.

The grid points are not distributed uniformly over the computational domain. They have greater density in the

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z- direction and have a lower density in the r- direction. The 2-D axisymmetric case with 28000 quadrilateral

grid cells are chosen and structured grid was used for the present simulation.

A grid independent solution study was made by performing the simulations for three different grids consisting of 14300, 28000 and 42000 nodes.

A mesh refinement study showed a grid of 28000 nodes to be fine enough to capture all the flow features.

Boundary conditions have to be specified in order to solve the governing equations.

At the inlet the values can be calculated from the given conditions at the inlet boundary, see Fig. 3. The total inlet velocity vector inq has two components inV

and inU and they are related to each other by:

in inU q sin (10)

in inV q cos (11)

inin

in

Qq

A (12)

However, at the outlet boundary there is no

information about the velocity and pressure field and some assumptions have to be made. The diffusion fluxes in the direction normal to the exit plane are assumed to be zero. The pressure at the outlet boundary is calculated from the assumption that radial velocity at the exit is neglected since it does not have the space to develop, so that the pressure gradient from r-momentum is given by:

2Vpr r

(13)

At the solids walls, the no-slip condition was applied

where the velocities at the walls were specified to be zero. The center-line boundary was considered axis of symmetry. Experience has shown that typically 6000 iterations needed before the pressure data in the simulation stabilizes.

V. Results and Discussion The pressure drop coefficient is defined as:

2

2p

in

pCq

(14)

where out inp p p is the pressure drop between the outlet and inlet. The estimated uncertainty for the pressure drop coefficient Cp has appeared at the maximum of 8% . Fig. 5 compares the present experimental data with the RSM prediction of the

pressure drop coefficient Cp. It is clear that as the contraction ratio and the

Reynolds number Re increase, the pressure coefficient Cp increases. Stronger vortices will be produced by increasing the contraction ratio and/or Reynolds number, resulting in a higher tangential velocity and hence a higher pressure drop. It can be seen that the Reynolds stress model gives good agreement with the experimental data and the percentage difference error between the predicted and experiments is less than 9 %.

The following analysis illustrates the mean radial pressure distribution profile , and the predicted radial pressure will be compared with present experimental data. The mean radial pressure distribution profile is defined according to the following equation:

2

2 1

in

p r p r

q

(15)

where the normalized radius r is given by o

rrr

.

Fig. 6 compares the present experimental data with the RSM prediction of the radial pressure for Reynolds number Re=5172 and contraction ratio =24. It is clear that the pressure decreases slowly from the inlet (periphery) up to halfway along the disk and then decreases sharply as the flow approach the exit hole. Air enters through the peripheral gap between the two disks and converges to the center where it discharges axially through the exit hole in one of the disks.

This indicates that the flow moved towards a more favorable pressure gradient, hence the vortex flow accelerated according to the angular momentum conservation.

It can be seen that the Reynolds stress model gives good agreement with the present experimental data and the percentage difference error between the predicted and experiments is less than 10%.

The estimated uncertainty for the radial pressure has appeared at the maximum of 9% .

Fig. 5. Pressure drop coefficient at different Reynolds number

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Fig. 6. Radial Pressure Profile

VI. Conclusion Two disks flow with inlet swirl was investigated both

experimentally and numerically at different contraction ratio and Reynolds number. The Reynolds stress model is capable to predict the pressure drop and the radial pressure profiles. The results show clearly that as the contraction ratio and the Reynolds number increase, the pressure coefficient increases. It is clear that the radial pressure decreases slowly from the inlet and then decreases sharply as the flow approach the exit hole.

A comparison of the results with measurement shows clearly the ability of the Reynolds-stress turbulence model in capturing the major features of a confined swirling flow.

References [1] G.H. Vatistas, A note on liquid vortex sloshing and kelvin’s

equilibria, Journal of Fluid Mechanics, vol. 217, pp. 241-248, 1990.

[2] B. Osar, B.M. Cetegen, and A. Faghri, Experiments on the flow of a thin liquid film over a horizontal stationary and rotating disk surface,Experiments in Fluids, vol. 34, pp. 556-565, 2003.

[3] G. Gauthier , P. Gondret, F. Moisy, M. Rabaud , Instabilities in the flow between co-and counter-rotating disks,Journal of Fluid Mechanics, vol. 473, pp. 1-21, 2002.

[4] G.H. Vatistas, A. Ghila, and G. Zitouni, Radial inflow within two flat disks,ActaMechanica vol. 113, pp. 109-118, 1995.

[5] M. DeSantis,E.L Rakowsky, An experimental investigation of the viscous flow field in a pneumatic vortex rate sensor, ASME, 70-FLCS-16, pp.1-12, 1971.

[6] C. Kwok, N. Thinh, S. Lin, An investigation of confined vortex flow phenomena, Journal of Basic Engineering, Transactions of ASME, pp.689-696, 1972.

[7] J. Savino, E. Keshock, Experimental profiles of velocity components and radial pressure distribution in a vortex contained in a short cylindrical chamber, NASA TN D-3072, Library of University of CalifoniaSanDiego, pp. 2-32, 1965

[8] A. Singh,B. Vyas, U. Powle, Investigations on inward flow between two stationary parallel disks, Int. J. of Heat and Fluid Flowvol. 20, pp. 395-401, 1999.

[9] H. Murphy, M. Coxon, Symmetric sink flow between parallel plates, Trans. ASME J. Fluids Engg, vol. 100, pp. 477-484, 1978.

[10] J.H. Ferziger, M. Peric, Computational Methods for Fluid Dynamics (2nd edition, Springer, Verlag Berlin Heidelberg, Germany, 1999).

[11] M. Nallasamy, Turbulence models and their applications to the

prediction of internal flows, Computers and Fluids, vol.15, n. 2, pp. 151-194, 1987.

[12] A. Nejad, S. Vanka, Favaloro, M. Samimy, C. Langenfeld, Application of Laser Velocimetry for Characterization of Confined Swirling Flow, Transactions of the ASME, Journal of Engineering for Gas Turbines and Power, vol. 111, pp. 36-45, 1989

[13] R. Weber, Assessment of turbulence modeling for engineering prediction of swirling vortices in the near burner zone, International Journal of Heat and Fluid Flow, vol. 11, n. 3, pp. 225-235,1990.

[14] B.E. Launder, Second-moment closure and its use in modelling turbulent industrial flows, International Journal for Numerical Methods in Fluids,vol. 9, n. 8, pp. 963-985, 1989.

[15] M.A. Leschziner,Modelling engineering flows with Reynolds stress turbulence closure, Journal of Wind Engineering and Industrial Aerodynamics, vol. 35, n. 1, pp. 21-47, 1990.

[16] A.E. German, T. Mahmud,Modelling of non-premixed swirl burner flows using a Reynolds-stress turbulence closure,Fuel, vol. 84, n 5, pp. 583-594, 2005.

[17] W.P. Jones, A. Pascau, Calculation of Confined Swirling Flows with a Second Momentum Closure. Transaction of the ASME, vol. 111, pp. 248-255, 1989.

[18] A.J. Hoekstra, H.E. Derksen,V Akker, An Experimental and Numerical Study of Turbulent Swirling Flow in Gas Cyclones. Chemical Engineering Science, vol. 54, pp. 2055-2065, 1999.

[19] S. Jakirlic, K. Hanjalic, C. Tropea, Modeling Rotating and Swirling Turbulent Flows: A Perpetual Challenge. AIAA Journal, vol. 40, n. 10, pp. 1984-1996, 2002.

[20] L.N. Jones, P.H. Gaskell, H.M. Thompson, X.J. Gu, D.R. Emerson, Anisotropic, isothermal, turbulent swirling flow in a complex combustor geometry,Int. J. Numer. Meth. Fluids, vol. 47, pp. 1053–1059, 2005.

[21] A.M. Jawarneh,G.H. Vatistas,Y. Aboelkassem,Experimental Investigation of the Pressure Drop in a Sink-Swirl Flow within Two Disks, AIAA, Journal of Propulsion and Power, vol. 21, n. 4, pp. 759-760, 2005.

[22] G.H. Vatistas, W.Ghaly, and Tsifourdaris, Swirling Inflow Within the Narrow Gap of the Two Disks, J. propulsion and power, vol. 21, n.4, pp. 743-750, 2005.

[23] G. H. Vatistas, M. Fayed, and J. U. Soroardy, Strongly Swirling Turbulent Sink Flow Between Two Stationary Disks. J. Prop. and Power, vol. 24, n. 2, 2008.

[24] B.E. Launder, G.J. Reece, and W. Rodi, Progress in the Development of a Reynolds-Stress Turbulence Closure, J. Fluid Mech., vol. 68, n. 3, pp.537-566, 1975.

[25] F.S. Lien and M.A. Leschziner, Assessment of Turbulent Transport Models Including Non-Linear RNG Eddy-Viscosity Formulation and Second-Moment Closure, Computers and Fluids, vol. 23, n. 8, pp. 983-1004, 1994.

[26] M.M Gibson and B.E Launder, Ground Effects on Pressure Fluctuations in the Atmospheric Boundary Layer, J. Fluid Mech.,vol.86, pp.491-511, 1978.

[27] B.E. Launder, D.B. Spalding, Numerical Computation of Turbulent Flows, Computer Methods in Applied Mechanics and Engineering, vol. 3, n. 2, pp. 269-289, 1974.

[28] S.E. Kim and D. Choudhury, A Near-Wall Treatment Using Wall Functions Sensitized to Pressure Gradient, ASME FED, 217, Separated and Complex Flows. ASME, 1995, pp. 273-280.

[29] V. Patankar, Numerical Heat Transfer and Fluid Flow, Hemisphere, New York, 1980.

Authors’ information Ali M. Jawarneh, associate professor, Department of Mechanical Engineering, Hashemite University, Jordan. E-mail: jawarneh@hu.edu.jo

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International Review of Mechanical Engineering (IREME)

(continued from outside front cover)

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Analysis of Cenosphere - Aluminium Metal Matrix Composite for Engine Block by V. Saravanan, P. R. Thyla, S. R. Balakrishnan

1128

Experimental Investigations on Surface Roughness, Cutting Force and Tool Wear of Duplex Stainless Steel in End Milling Using Taguchi Method by D. Philip Selvaraj, P. Chandramohan, M. Mohanraj, P. K. Rajesh

1133

Microstructure and Dry Sliding Wear Behavior of AA2218 Based Self-Lubricating Metal Matrix Composites by A. Anandha Moorthy, N. Natarajan, P. K. Palani, M. Manojkumar

1142

Finite Element Analysis of Super Energy Saving Locking System Towards Enhancing Door Lock Performance and Security by Sivaraos, A. A. Aziz, R. Izamshah, Taufik, A. Hambali

1147

Experimental Study to Identify Common Engine Part Load Conditions between Malaysian City Driving and NEDC Test by I. Zahari, M. A. Abas, N. I. Mat Arishad, S. F. Zainal Abidin, M. F. Muhamad Said

1152

CFD and Experimental Analysis of a Condenser for Domestic Desalination System by Shashikant S. Patil, A. B. Auti, T. P. Singh

1159

Brake Motion Control for Quadruped Hopping Robot by Using Reference Height Control System by A. M. Kassim, T. Yasuno, Sivaraos, H. I. Jaafar, F. A. Jafar

1164

An Innovative Study and Binary Modeling of Thermal Power Plant Using Artificial Neural Network and Multiple Linear Regression by S. Devi, L. Sivakumar, M. Saravanan

1171

Review of Structural Assessment of Pipe Bends by S. Sellakumar, R.Venkatasamy

1180

(continued on outside back cover) Abstracting and Indexing Information:

Cambridge Scientific Abstracts (CSA/CIG) Academic Search Complete (EBSCO Information Services) Elsevier Bibliographic Database SCOPUS Index Copernicus (Journal Master List): Impact Factor 6.46

Autorizzazione del Tribunale di Napoli n. 6 del 17/01/2007

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(continued from inside back cover)

Stresses in Thin, Multi-Layer Pipes in Large Radial Vibrations by Shahin Nayyeri Amiri, Asad Esmaeily, Javad Safadoust

1189

Numerical Simulation of Hot Isostatic Pressing Process for the Manufacture of Parts Used in Biomechanics by A. Kherraf, K. Zidani, H. Mazouz, L. Chelghoum, L. Rezoug

1194

Development of On-Line Drill Wear Monitoring System in Machining of AISI 1018 Steel Using Virtual Instrumentation by S. Rajesh, K. Marimuthu

1198

Properties of Silica Sand-Based Castings Prepared with Different Proportions of Steel Industry Fly Ash by P. Karunakaran, C. Jegadheesan, C. Rangasami, P. Sengottuvel

1207

Active Disturbance Rejection Control of Nonlinear Thermal Process by Maruthai Suresh, Chinnappan Selvakumar, Ranganathan Rani Hemamalini

1213

Extracted by "4th ICOME 2013 - Virtual Forum"

Numerical Solution to Thermal Fluid Flow Through Porous Media Using Lattice Boltzmann Method by Nor Azwadi C. Sidik, Syahrullail Samion

1218

A Comparison of Cylindrical and Row Trenched Cooling Holes with Alignment Angle of 90 Degree Near the Combustor Endwall by Ehsan Kianpour, Nor Azwadi C. Sidik, Syahrullail Samion

1223

Feasibility Study of Dish Stirling Systems in Malaysia by M. E. Zailani

1229

1970-8734(201309)7:6;1-F

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