2016
9
2
2
0
Experimental Investigation of the Flow Control of Wake Cylinder by a Plate with Different Geometrical Ends
2
2
An experimental study was carried out on the wake of a cylinder on the back of which a plate is installed parallel to the fluid flow, with different terminal angles, where the Reynolds number is 50000. At the end of the plate, blades with the height of 0.25 equal to the cylinder diameter and with 45, 90 and 135 degrees angle from the horizon, are installed where the cylinder diameter is equal to the plate length. The plate effects on the variation of drag coefficient, medium velocity profiles, reduced velocity, half of the entrance, turbulence intensity and Strouhal number are investigated. The results showed that the drag coefficient for cylinder including the plate, regardless of the end angle, is smaller than the isolated cylinder. The existence of a plate with a terminal angle of 45 degree led to more reduction in drag coefficient of the cylinder.
1

1
10


A.B.
Khoshnevis
Department of Mechanical Engineering,
University of Hakim Sabzevari, Iran
Department of Mechanical Engineering,
University
Iran
khosh1966@yahoo.com


AmirReza
Mamouri
Engineering Faculty,
Eshragh Institute of higher Education, Bojnourd, Iran
Engineering Faculty,
Eshragh Institute of
Iran
amirelmir3000@yahoo.com


AmirReza
Mamouri
Engineering Faculty,
Eshragh Institute of higher Education, Bojnourd, Iran
Engineering Faculty,
Eshragh Institute
Iran


V.
Barzenoni
Department of Mechanical Engineering,
University of Hakim Sabzevari, Iran
Department of Mechanical Engineering,
University
Iran
v.barzanooni@gmail.com
Cylinder
Drag coefficient
Strouhal number
Turbulence intensity
[[1] Blevins, R. D., “Acoustic Modes of Heat Exchanger Tube Bundles”, 1985, Journal of sound and Vibration, Vol. 109, No. 1, 1986, pp. 1931. ##[2] Hamma, J. C. L., Paranthoen, P., “The control of vortex shedding behind heated circular cylinders at low Reynolds numbers”, Journal of Experiments in Fluids, Vol. 10, 1991, pp. 224229. ##[3] Bayazitoglu, Y., Sunryanaratana, P. V. R., “Dynamics of oscillating viscous droplests immersed in viscous media”, Journal of Acta Mechanica, Vol. 95, Texas 1992, pp. 167183. ##[4] Framsson, J. H. M., Konieczny, P., and Alfredsson, P. H., “Flow around a porous cylinder subject to continuous suction or blowing”, Journal of Fluids and Structures, Vol. 19, 2004, pp. 10311048. ##[5] Zhijin, Li, Navon, I. M., Hussaini, M.Y., and Le Dimet, F.X., “Optimal control of cylinder wakes via suction and blowing”, Journal of Computers & Fluids, Vol. 32, 2003, pp. 149171. ##[6] Mutschke, G., Shatrov, V., and Gerbeth, G., “Cylinder wake control by magnetic fields in liquid metal flows”, Journal of Experimental Thermal and Fluid Science, Vol. 16, 1998, pp. 9299. ##[7] Igbalajobi, A., McClean, J. F., Sumnern, D., and Bergstrom, D. J., “The effect of a wakemounted splitter plate on the flow around a surface mounted finiteheight circular cylinder”, Journal of Fluids and Structures, Vol. 37, 2013, pp. 185–200. ##[8] Yu, P., Zeng, Y., Lee, T. S., Bai, H. X., and Low, H. T., “Wake structure for flow past and through a porous square cylinder”, International Journal of Heat and Fluid Flow, Vol. 31, 2010, pp. 141–153. ##[9] Bergmann, M., Cordier, L., “Optimal control of the cylinder wake in the laminar regime by trustregion methods and POD reducedorder models”, Journal of Computational Physics, Vol. 227, 2008, pp. 7813–7840. ##[10] Salari. M, Ardakani. M. A., and Taghavi Zonnor, R., “Experimental Study for Effect of Free Flow Temperature Changes and Hot Wire Anemometer on sensors calibration and Velocity measurement”, Journal of Mechanics and AeroSpace, 1384, Vol. 1, No. 3, pp. 4959 (in Persian). ##[11] Ardakani, M. A., “Hot Wire Anemometer”, Vol. 1, Khaje Nasiroddin Tosi University, 1385 (in Persian). ##[12] Saha, A. K., Muralidhar, K., and Biswas, G., “Experimental Study of Flow Past a Square Cylinder at High Reynolds Numbers”, Experiments in Fluids, Vol. 29, No. 4, 2008, pp. 553563. ##[13] Shadaram A., Azimifrad, M., and Rostami, N., “Study of characteristic flow at the near wake of square cylinder”, J. of Mechanical aerospace Vol. 3, No. 4, 1386 (in persain). ##[14] Goldstein, S., “A Note on the Measurement of Total Head and Static Pressure on a Turbulent Stream”, Proceedings of the Royal Society of London, Series A, Vol. 155, No. 32, 1936, pp. 570575. ##[15] LU, B., Bragg, M. B., “Experimental Investigation of the WakeSurvey Method for a Bluff Body with Highly Turbulent Wake”, AIAA3060, Year 2002. ##[16] LU, B., Bragg, M. B., “Experimental Investigation of Airfoil Drag Measurements with Simulated LeadingEdge Ice Using the WakeSurvey Method”, AIAA3919, Year 2000. ##[17] LU, B., Bragg, M. B., “Airfoil Drag Measurement with Simulated Leading Edge Ice Using the WakeSurvey Method”, AIAA1094, Year 2003. ##[18] Van Dam, C. P., “Recent Experience with Different Methods of Drag Prediction”, Progress in aerospace. Science, Vol. 35, No. 8, 1999, pp. 751798. ##[19] Sanieinejad, M., “Fundamentals of Turbulent Flows and Turbulence modeling”, daneshnegar publisher, 978964292735337, Tehran 1388 (in Persian). ##[20] Wang, J. S., Qiao, X. Q., “Pressure distribution, Fluctuating Forces and vortex shedding behavior of circular cylinder with rotatable splitter plates”, Journal of Fluids and Structures, Vol. 12, 2012, pp. 263278. ##[21] Fox, R., Mcdonald, A., “Introduction to fluid mechanics”, 4th Ed. ##]
Energy Absorption by ThinWalled Tubes with various Thicknesses in Rectangular and Square Sections under Different QuasiStatic Conditions: Experimental and Numerical Studies
2
2
Impact is one of the most important subjects which always have been considered in mechanical science. Nature of impact is such that which makes its control a hard task. Therefore it is required to adopt a safe and secure mechanism for transferring the impact to other vulnerable parts of a structure, when it is necessary. One of the best methods of absorbing impact energy is using Thinwalled tubes, where the tubes collapse under impact by absorbing energy, while this prevents the damage to other parts. Purpose of the present study is to survey the deformation and energy absorption of tubes with different type of cross section (rectangular or square) and with similar volumes, height, mean cross section, and material under different speed loading. Lateral loading of tubes are quasistatic type and in addition to the numerical analysis, also experimental experiment has been performed to evaluate the accuracy of the results. Results from the survey indicates that at the same conditions which mentioned above, samples with square cross sections, absorb more energy compared to rectangular cross sections; also by increasing the loading speed and thickness, the energy absorption would be more..
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11
18


K. Hoseini
Safari
Faculty of Industrial and Mechanical Engineering, Islamic Azad University, Qazvin Branch, Qazvin, Iran
Faculty of Industrial and Mechanical Engineering,
Iran
safari@dena.kntu.ac.ir


Y.
Mohammadi
Faculty of Industrial and Mechanical Engineering, Islamic Azad University, Qazvin Branch, Qazvin, Iran
Faculty of Industrial and Mechanical Engineering,
Iran
u.mohammadi@gmail.com


Sajjad
Dehghanpour
Department of Mechanical Eng., Toyserkan Branch, Islamic Azad University, Toyserkan, Iran
Department of Mechanical Eng., Toyserkan
Iran
energy absorption
Inplane loading
LSDYNA
QuasiStatic
[[1] Carney, J. F, III, Austin CD, “Reid SR. Modeling of steel tube vehicular crash cushion”, ASCE Transportation Engineering 1983, Vol. 109, No. 3, pp. 33146. ##[2] Reid, S.R, Drew, SLK, Carney, J. F, III. “Energy absorbing capacities of braced metal tubes”, International Journal of Mechanical Sciences 1983, Vol. 25, No. 910, pp. 64967. ##[3] Watson, A. R, Reid, S. R, Johnson, W., and Thomas, S. G., “Large deformations of thinwalled circular tubes under transverse loadingII”, International Journal of Mechanical Sciences 1976, Vol. 18, pp. 38797. ##[4] Watson, A. R, Reid, S. R, Johnson, W., “Large deformations of thinwalled circular tubes under transverse loadingIII”, International Journal of Mechanical Sciences 1976, Vol.18, pp. 5019. ##[5] Johnson, W., Reid, S. R, and Reddy, T. Y., “The compression of crossed layers of thin tubes”, International Journal of Mechanical Sciences 1977, Vol. 19, pp. 42337. ##[6] Mutchler, L. D., “Energy absorption of aluminum tubing”, Transactions of ASME, Journal of Applied Mechanics 1960, Vol. 27,pp. 7403. ##[7] DeRuntz, J. A, Hodge, P. G., “Crushing of a tube between rigid plates”, Transactions of ASME, Journal of Applied Mechanics 1963, Vol. 30, pp. 3915. ##[8] Gupta, N. K., Sekhon, G. S. and Gupta, P. K., “Study of lateral compression of round metallic tubes”, Thin Walled Structures, 2005, No. 43, pp. 895922. ##[9] Niknejad, A., Liaghat, G. H., Moslemi Naeini, H., and Behravesh, A. H., “Experimental and theoretical investigation of the first fold creation in thin walled columns”, Acta Mechanica Solida Sin 2010; Vol. 23, pp. 353–60. ##[10] Niknejad, A., Liaghat, G. H., Moslemi Naeini, H., and Behravesh, A.H., “Theoretical and experimental studies of the instantaneous folding force of the polyurethane foamfilled square honeycombs”, Mater Des 2011, Vol. 32, pp. 69–75. ##[11] Niknejad, A., Abedi, M. M, Liaghat, G. H, and Zamani Nejad, M., “Prediction of the mean folding force during the axial compression in foamfilled grooved tubes by theoretical analysis”, Mater Des 2012, Vol. 37, pp. 144–51. ##[12] Abedi, M. M, Niknejad, A., Liaghat, G. H, and Zamani Nejad, M., “Theoretical and experimental study on empty and foamfilled columns with square and rectangular cross section under axial compression”, Int J Mech Sci 2012, Vol. 65, pp. 134–46. ##[13] Yan, L., Chouw, N., “Crashworthiness characteristics of flax fibre reinforced epoxy tubes for energy absorption application”, Mater Des 2013, Vol. 51, pp. 629–40. ##[14] Yan, L., Chouw, N., Jayaraman, K., “Effect of triggering and polyurethane foamfiller on axial crushing of natural flax/epoxy composite tubes”, Mater Des 2014, Vol. 56, pp. 528–41. ##[15] Mahdi, E., Sultan, H., Hamouda, A. M. S, Omer, A. A., and Mokhtar, A. S., “Experimental optimization of composite collapsible tubular energy absorber device”, ThinWalled Struct 2006, Vol. 44, pp. 1201–11. ##[16] Zhang, Y., Sun, G., Li, G., Luo, Z., and Li, Q., “Optimization of foamfilled bitubal structures for crashworthiness criteria”, Mater Des 2012, Vol. 38, pp. 99–109. ##[17] Arnold, B., Altenhof, W., “Experimental observations on the crush characteristics of AA6061 T4 and T6 structural square tubes with and without circular discontinuities”, Int J Crashworthines 2004, Vol. 9, pp. 73–87. ##[18] Cheng, Q., Altenhof, W., and Li, L., “Experimental investigations on the crush behavior of AA6061T6 aluminum square tubes with different types of throughhole discontinuities”, ThinWalled Struct 2006, Vol. 44, pp. 441–54. ##[19] Alavi Nia, A., Badnava, H., Fallah Nejad, Kh., “An experimental investigation on crack effect on the mechanical behavior and energy absorption of thinwalled tubes”, Mater Des 2011, Vol. 32, pp. 594–607. ##]
The Effects of Local Variation in Thermal Conductivity on Heat Transfer of a Micropolar Fluid Flow Over a Porous Sheet
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2
This study is considering a micropolar fluid flow over a porous stretching sheet in the presence of thermal radiation and uniform magnetic field. The effects of local variation in thermal conductivity of micropolar fluid on heat transfer rate from the sheet are investigated; besides, the impacts of radiation, magnetic field and porous sheet on variations of thermal boundary layer thickness are considered. The results show that the increase of thermal conductivity thickens thermal boundary layer, so heat transfer rate decreases. In addition, intensification of magnetic field and the presence of radiation lower the absolute values of temperature gradient on the wall, and reduce the cooling rate of the sheet. On the contrary, the increase of suction and material parameter has positive influence on cooling rate of the sheet.
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19
25


Reza
Keimanesh
Department of Mechanical Engineering,
K. N. Toosi University of Technology, Iran
Department of Mechanical Engineering,
K.
Iran
reza_keimanesh@yahoo.com


Cyrus
Aghanajafi
Department of Mechanical Engineering,
K. N. Toosi University of Technology, Iran
Department of Mechanical Engineering,
K.
Iran
aghanajafi@kntu.ac.ir
Magnetic Field
Micropolar fluid
Radiation
Thermal conductivity
[[1] Wang, C.Y., “Liquid film on an unsteady stretching Surface,” Quarterly of Applied Mathematics, Vol. 48, No. 4, 1990, pp. 601 610. ##[2] Mahapatra, T., Gupta, A.S., “Stagnationpoint flow of a viscoelastic fluid towards a stretching surface,” International Journal of Nonlinear Mechanics, Vol. 39, No. 5, 2004, pp. 811 820. ##[3] Miklavcic, M., Wang, C.Y., “Viscous flow due to a shrinking sheet,” Quarterly of Applied Mathematics, Vol. 64, No. 2, 2006, pp. 283 290. ##[4] Wang, C.Y., “Stagnation flow towards a shrinking sheet,” International Journal of NonLinear Mechanics, Vol. 43, No. 5, 2008, pp. 377 382. ##[5] Fang, T., “Boundary layer flow over a shrinking sheet with powerlaw velocity,” International Journal of Heat and Mass transfer, Vol. 51, No. 25 26, 2008, pp. 5838 5843. ##[6] Ishak, A., Lok, Y.Y., Pop, I., “NonNewtonian powerlaw fluid flow past a shrinking sheet with suction,” Chemical Engineering Communications, Vol. 199, No. 1, 2012, pp. 142 150. ##[7] Bachok, N., Ishak, A., Pop, I., “Boundary layer stagnationpoint flow and heat transfer over an exponentially stretching/shrinking sheet in a nanofluid,” International Journal of Heat and Mass transfer, Vol. 55, No. 25 26, 2012, pp. 8122 8128. ##[8] Xu, H., Pop, I., You, X.C., “Flow and heat transfer in a nanoliquid film over an unsteady stretching surface,” International Journal of Heat and Mass Transfer, Vol. 60, 2013, pp. 646 652. ##[9] Eringen, A.C., “Simple microfluids,” International Journal of Engineering Science, Vol. 2, No. 2, 1964, pp. 205 217. ##[10] Sankara, K.K., Watson, L.T., “Micropolar flow past a stretching sheet,” Journal Mathematics and Physics (ZAMP), Vol. 36, No. 6, 1985, pp. 845 853. ##[11] Hassanien, I.A., Gorla, R.S.R., “Heat transfer to a micropolar fluid from a nonisothermal stretching sheet with suction and blowing,” Acta Mechanica, Vol. 84, No. 1, 1990, pp. 191 199. ##[12] Alomari, A.K., Noorani, M.S.M., Nazar, R., “Homotopy solution for flow of a micropolar fluid on a continuous moving surface,” International Journal for Numerical Methods in Fluids, Vol. 66, No. 5, 2011, pp. 608 621. ##[13] Yacob, N.A., Ishak, A., “Micropolar fluid flow over a shrinking sheet,” Meccanica, Vol. 47, No. 2, 2012, pp. 293 299. ##[14] Hassanien, I.A., Ibrahim, F.S., Gorla R.S.R., “Mixed convection boundary layer flow of a micropolar fluid on a horizontal plate,” Chemical Engineering Communications, Vol. 170, No. 1, 1998, pp. 117 131. ##[15] Mehraban Rad, P., Aghanajafi, C., “The Effect of Thermal Radiation on Nanofluid Cooled Microchannels,” Journal of fusion energy, Vol. 28, No. 1, 2009, pp. 91 100. ##[16] Ali, F.M., Nazar, R., Arifin, N.M., Pop, I., “Unsteady flow and heat transfer past an axisymmetric permeable shrinking sheet with radiation effect,” International Journal for Numerical Methods in Fluids, Vol. 67, No. 10, 2011, pp. 1310 1320. ##[17] Hussain, M., Ashraf, M., Nadeem, S., Khan, M., “Radiation effects on the thermal boundary layer flow of a micropolar fluid towards a permeable stretching sheet,” Journal of the Franklin Institute, Vol. 350, No. 1, 2013, pp. 194 210. ##[18] Ouaf, M.E.M., “Exact solution of thermal radiation on MHD flow over a stretching porous sheet,” Applied Mathematics and Computation, Vol. 170, No. 2, 2005, pp. 1117 1125. ##[19] Fang, T., Zhang, J., “Closedform exact solution of MHD viscous flow over a shrinking sheet,” Communications in Nonlinear Science and Numerical Simulation, Vol. 14, No. 7, 2009, pp. 2853 2857. ##[20] Taklifi, A., Aghanajafi, C., Akrami, H., “The effect of MHD on a porous fin attached to a vertical isothermal surface,” Transport in porous media, Vol. 85, No. 1, 2010, pp. 215 231. ##[21] Noor, N.F.M., Abbasbandy, S., Hashim, I., “Heat and mass transfer of thermophoretic MHD flow over an inclined radiate isothermal permeable surface in the presence of heat source/sink,” International Journal of Heat and Mass Transfer, Vol. 55, No. 7 8, 2012, pp. 2122 2128. ##[22] Taklifi, A., Aghanajafi, C., “MHD nonDarcian flow through a nonisothermal vertical surface embedded in a porous medium with radiation,” Meccanica, Vol. 47, No. 4, 2012, pp. 929 937. ##[23] Mukhopadhyay, S., “MHD boundary layer flow and heat transfer over an exponentially stretching sheet embedded in a thermally stratified medium,” Alexandria Engineering Journal, Vol. 52, No. 3, 2013, pp. 259 265. ##[24] Jena, S.K., Mathur, M.N., “Similarity solutions for laminar free convection flow of a thermomicropolar fluid past a nonisothermal vertical flat plate,” International Journal of Engineering Science, Vol. 19, No. 11, 1981, pp. 1431 1439. ##[25] Guram, G.S., Smith, A.C., “Stagnation flow of micropolar fluids with strong and weak interactions,” Computers & Mathematics with Applications, Vol. 6, No. 2, 1980, pp. 213 233. ##[26] Ahmadi, G., “Selfsimilar solution of imcompressible micropolar boundary layer flow over a semiinfinite plate,” International Journal of Engineering Science, Vol. 14, No. 7, 1976, pp. 639 646. ##[27] Peddieson, J., “An application of the micropolar fluid model to the calculation of turbulent shear flow,” International Journal of Engineering Science, Vol. 10, No. 1, 1972, pp. 23 32. ##[28] Grubka, L.J., Bobba, K.M., “Heat transfer characteristics of a continuous, stretching surface with variable temperature,” ASME Journal of Heat Transfer, Vol. 107, No. 1, 1985, pp. 248 250. ##[29] Ali, M.E., “Heat transfer characteristics of a continuous stretching surface,” Heat and Mass Transfer, Vol. 29, No. 4, 1994, pp. 227 234. ##[30] Chen, C.H., “Laminar mixed convection adjacent to vertical, continuously stretching sheets,” Heat and Mass Transfer, Vol. 33, No. 5, 1998, pp. 471 476. ##[31] Ishak, I., “Thermal boundary layer flow over a stretching sheet in a micropolar fluid with radiation effect,” Meccanica, Vol. 45, No. 3, 2010, pp. 367 373. ##[32] Mahmoud, M. A. A., “Thermal radiation effects on MHD flow of a micropolar fluid over a stretching surface with variable thermal conductivity,” Physica A, Vol. 375, No. 2, 2007, pp. 401 410. ##]
Investigation of Mechanical Property and Microstructure of Nanocomposite AZ31/SiC Fabricated by Friction Stir Process
2
2
The friction stir process (FSP) is a solid state process, which has been used to insert reinforcing particles into the structure of a material to create a composite with improved properties. Magnesium is a light structural metal that is increasingly used in the aerospace and automobile industries. In this research, SiC nanoparticles were added to AZ31 alloy using FSP in two overlaps of 100% and 50% passes. In 100% pass overlapping, nanoparticles were added in 4, 8 and 16 volume percentages and in 50% pass overlapping only nanoparticles in 4 volume percent were added. The FSP process performed as 4 consecutive passes in both overlaps along with rapid cooling. Microstructure, hardness and tensile strength of created composites were examined. The results suggested that adding reinforcing materials causes reduction in the size of the grains, uniformity of structure and increase in the hardness of material. SiC nanoparticles distributed uniformly through the AZ31 alloy. By increasing volume fraction of reinforcing materials, yield stress of the material increased but ultimate stress and formability properties reduced. In 50% overlapping state, the yield stress in directions, either parallel or perpendicular to the pin direction, increased rather than 100% overlapping state, but the ultimate stress and elongation properties reduced. This reduction was greater in the perpendicular direction relative to the pin direction.
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27
34


ahmad
haghani
Department of Mechanics, Faculty of Engineering, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
Department of Mechanics, Faculty of Engineering,
Iran
a.haghani@srbiau.ac.ir


Sayed Hassan
Nourbakhsh
Department of Mechanical Engineering,
University of Shahrekord, Shahrekord, Iran
Department of Mechanical Engineering,
University
Iran
sh.nourbakhsh@eng.sku.ac.ir


Mehdi
Jahangiri
Department of Mechanical Engineering, Faculty of Engineering,
Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
Department of Mechanical Engineering, Faculty
Iran
mehdi_jahangeri@yahoo.com
Friction stir process
Magnesium AZ31
Mechanical strength
SiC nanoparticles
[[1] Mordike, B., L., Ebert, T., “Magnesium: Properties, applications, potential”, Journal of Materials Science and Engineering: A, Vol. 302, 2001, pp. 3745. ##[2] Darras, B., Kishta, E., “Submerged friction stir processing of AZ31 Magnesium alloy”, Journal of Materials & Design, Vol. 47, 2013, pp. 133137. ##[3] Pradeep, S., Pancholi, V., “Effect of microstructural inhomogeneity on superplastic behaviour of multipass friction stir processed aluminium alloy”, Journal of Materials Science and Engineering: A, Vol. 561, 2013, pp. 7887. ##[4] Ramesh, K., N., Pradeep, S., and Pancholi, V., “Multipass FrictionStir Processing and its Effect on Mechanical Properties of Aluminum Alloy 5086”, Journal of Metallurgical and Materials Transaction A, Vol. 43, 2012, pp. 43114319. ##[5] Venkateswarlu, G., Devaraju, D., Davidson, M., J., Kotiveerachari, B., and Tagore, G., “Effect of overlapping ratio on mechanical properties and formability of friction stir processed Mg AZ31B alloy”, Journal of Materials & Design, Vol. 45, 2013, pp. 480486. ##[6] Yuan, W., Mishra, R., S., “Grain size and texture effects on deformation behavior of AZ31 magnesium alloy”, Journal of Materials Science and Engineering: A, Vol. 558, 2012, pp. 716724. ##[7] Dolatkhah, A., Golbabaei, P., BesharatiGivi, M., K., and Molaiekiya, F., “Investigating effects of process parameters on microstructural and mechanical properties of Al5052/SiC metal matrix composite fabricated via friction stir processing”, Journal of Materials & Design, Vol. 37, 2012, pp.458464. ##[8] Salehi, M., Saadatmand, M., and Aghazadeh Mohandesi, J., “Optimization of process parameters for producing AA6061/SiC nanocomposites by friction stir processing”, Journal of Transactions of Nonferrous Metals Society of China, Vol. 22, 2012, pp. 10551063. ##[9] Choi, D. H., Kim, Y. I., Kim, D., and Jung, S. B., “Effect of SiC particles on microstructure and mechanical property of friction stir processed AA6061T4”, Journal of Transactions of Nonferrous Metals Society of China, Vol. 22, 2012, pp. 614618. ##[10] Mostafapour Asl, A., Khandani, S., T., “Role of hybrid ratio in microstructural, mechanical and sliding wear properties of the Al5083/Graphitep/Al2O3p a surface hybrid nanocomposite fabricated via friction stir processing method”, Journal of Materials Science and Engineering: A, Vol. 559, 2013, pp. 549557. ##[11] Zahmatkesh, B., Enayati, M., H., “A novel approach for development of surface nanocomposite by friction stir processing”, Journal of Materials Science and Engineering: A, Vol. 527, 2010, pp. 67346740. ##[12] Rejil, C., M., Dinaharan, I., Vijay, S., J., and Murugan, N., “Microstructure and sliding wear behavior of AA6360/(TiC+B4C) hybrid surface composite layer synthesized by friction stir processing on aluminum substrate”, Journal of Materials Science and Engineering: A, Vol. 552, 2012, pp. 336344. ##[13] Morisada, Y., Fujii, H., Nagaoka, T., and Fukusumi, M., “Effect of friction stir processing with SiC particles on microstructure and hardness of AZ31”, Journal of Materials Science and Engineering: A, Vol. 433, 2006, pp. 5054. ##[14] Najafi, M., Nasiri, A., M., and Kokabi, A., H., “Microstructure and hardness of friction stir processed AZ31 with SiC”, International Journal of Modern Physics B, Vol. 22, 2008, pp. 28792885. ##[15] Asadi, P., Faraji, G., and Besharati, M., K., “Producing of AZ91/SiC composite by friction stir processing (FSP)”, International Journal of Advanced Manufacturing Technology, Vol. 51, 2010, pp. 247260. ##[16] Asadi, P., Faraji, G., Masumi, A., and Besharati, M., K., “Experimental Investigation of MagnesiumBase Nanocomposite Produced by Friction Stir Processing: Effects of Particle Types and Number of Friction Stir Processing Passes”, Journal of Metallurgical and Materials Transaction A, Vol.42, 2011, pp. 28202832. ##[17] Sun., K., Shi, Q., Y., Sun, Y., J., and Chen, G., Q., “Microstructure and mechanical property of nanoSiCp reinforced high strength Mg bulk composites produced by friction stir processing”, Journal of Materials Science and Engineering: A, Vol. 547, 2012, pp. 3237. ##[18] Hung, F. Y., Shih, C. C., Chen, L. H., and Lui, T. S., “Microstructures and high temperature mechanical properties of friction stirred AZ31–Mg alloy”, Journal of Alloys and Compounds, Vol. 428, 2007, pp. 106114. ##[19] Jiang, Y., Yang, X., Miura, H., and Sakai, T., “NanoSiO2 Particles Reinforced Magnesium alloy produced by friction stir processing”, Journal of Review Advanced Material Science, Vol. 33, 2013, pp. 2932. ##[20] Ma, Z., Y., Sharma, S., R.,and Mishra, R., S., “Effect of multiplepass friction stir processing on microstructure and tensile properties of a cast aluminum–silicon alloy”, Journal of Scripta Materialia, Vol. 54, 2006, pp. 16231626. ##[21] Gandra, J., Miranda, R., M., and Vilaça, P., “Effect of overlapping direction in multipass friction stir processing”, Journal of Materials Science and Engineering: A, Vol. 528, 2011, pp. 55925599. ##[22] Chang, C., I., Du, X., H., and Huang, J., C., “Achieving ultrafine grain size in Mg–Al–Zn alloy by friction stir processing”, Journal of Scripta Materialia, Vol. 57, 2007, pp. 209212. ##[23] Nascimento, F., Santos, T., Vilaça, P., Miranda, R., M., and Quintino, L., “Microstructural modification and ductility enhancement of surfaces modified by FSP in aluminium alloys”, Journal of Materials Science and Engineering: A, Vol. 506, 2009, pp. 1622. ##[24] Liu, Z., Y., Xiao, B., L., Wang, W., G., and Ma, Z., Y., “Singly dispersed carbon nanotube/aluminum composites fabricated by powder metallurgy combined with friction stir processing”, Journal of Carbon, Vol. 50, 2012, pp. 18431852. ##[25] Morisada, Y., Fujii, H., Nagaoka, T., and Fukusumi, M., “MWCNTs/AZ31 surface composites fabricated by friction stir processing”, Journal of Materials Science and Engineering: A, Vol. 419, 2006, pp. 344348. ##[26] Izadi, H., Gerlich, A., P., “Distribution and stability of carbon nanotubes during multipass friction stir processing of carbon nanotube/aluminum composites”, Journal of Carbon, Vol. 50, 2012, pp. 47444749. ##[27] Chawla, N., Shen, Y. L., “Mechanical Behavior of Particle Reinforced Metal Matrix Composites”, Journal of Advanced Engineering Materials, Vol. 3, 2001, pp. 357370. ##]
Development of Boundary Layer of Highly Elastic Flow of the Upper Convected Maxwell Fluid over a Stretching Sheet
2
2
High Weissenberg boundary layer flow of viscoelastic fluids on a stretching surface has been studied. The flow is considered to be steady and two dimensional. Flows of viscoelastic liquids at high Weissenberg number exhibit stress boundary layers near walls. These boundary layers are caused by the memory of the fluid. Upon proper scaling and by means of an exact similarity transformation, the nonlinear momentum and constitutive equations of each layer transform into the respective system of highly nonlinear and coupled ordinary differential equations. Effects of variation in pressure gradient and Weissenberg number on velocity profile and stress components are investigated. It is observed that the value of stress components decrease by Weissenberg number. Moreover, the results show that increasing the pressure gradient results in thicker velocity boundary layer. It is observed that unlike the Newtonian flows, in order to maintain a potential flow, normal stresses must inevitably develop in far fields.
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35
44


Meysam
Mohamadali
Department of Mechanical and Aerospace Engineering,
Science and Research Branch, Islamic Azad University, Tehran, Iran
Department of Mechanical and Aerospace Engineering
Iran
mmohamadali@gmail.com


Nariman
Ashrafi
Department of Mechanical and Aerospace Engineering,
Science and Research Branch, Islamic Azad University, Tehran, Iran
Department of Mechanical and Aerospace Engineering
Iran
n_ashrafi@hotmail.com
Boundary layer
High weissenberg flow
Nonlinear viscoelastic fluid
Similarity solution
[[1] Crane, L. J., “Flow past a stretching sheet”, ZAMP, Vol. 21, 1970, pp. 645–647. ##[2] Prasad, K. V., Santhi, S. R., and Datti, P. S:, “NonNewtonian powerlaw fluid flow and heat transfer over a nonlinearly stretching surface”, Appl. Math., Vol. 3, No. 5, 2012, pp. 425435. ##[3] Xu, H., and Liao, S. J:, “Laminar flow and heat transfer in the boundarylayer of nonNewtonian fluids over a stretching flat sheet”, Comput. Math. Appl., Vol. 57, 2009, pp. 14251431. ##[4] Abel, M. S., Datti, P. S., and Mahesha, N., “Flow and heat transfer in a powerlaw fluid over a stretching sheet with variable thermal conductivity and nonuniform heat source”, Int. J. Heat Mass Transfer, Vol. 52, 2009, pp. 2902–2913. ##[5] Wang, C., “Analytic solutions for a liquid film on an unsteady stretching surface”, Heat Mass Transfer, Vol. 42, 2006, pp.759–766. ##[6] Ashrafi, N., Mohamadali, M., “High Weissenberg Number Stress Boundary Layer for the Upper Convected Maxwell Fluid”, Proceedings of the ASME International Mechanical Engineering Congress & Exposition, Vol. 8B, Heat Transfer and Thermal Engineering, Montreal , 2014, pp. 201207. ##[7] Hassanien, I. A., “Flow and heat transfer on a continuous flat surface in a parallel free stream of viscoelastic secondorder fluid”, Appl. Sci. Res., Vol. 49, 1992, pp. 335344. ##[8] Schichting., H., “Boundary Layer Theory”, sixth ed., McGraw Hill, New York, 1964, Chap 7. ##[9] Hayat, T., Fetecau, C., Abbas, Z., and Ali, N., “Flow of a viscoelastic fluid with fractional Maxwell model between two side walls due to suddenly moved plate”, Nonlinear Anal. Real World Appl., Vol. 9, 2008, pp. 22882295. ##[10] Shateyi, S., “A new numerical approach to MHD flow of a Maxwell fluid past a vertical stretching sheet in the presence of thermophoresis and chemical reaction”, Bound. Val. Prob., Vol. 196, 2013. ##[11] Fetecau, C., Jamil, M., Fetecau, C., and Siddique, I., “A note on the second problem of Stokes for Maxwell fluids”, Int. J. NonLinear Mech., Vol. 44, 2009, pp. 10851090. ##[12] Hayat, T., Shehzad, S. A., and Alsaedi, A., “Study on threedimensional flow of Maxwell fluid over a stretching surface with convective boundary conditions”, Int. J. Phys. Sci., Vol. 7, No. 5, 2012, pp.761768. ##[13] Awais, M., Hayat, T., Alsaedi, A., and Asghar, S., “Timedependent threedimensional boundary layer flow of a Maxwell fluid”, Computers & Fluids, Vol. 91, 2014, pp. 21–27. ##[14] Rajagopal, K. R., Boundary layers in nonlinear fluids, in: M.D.P. Monteivo Marques, Trends in Applications of Mathematics to Mechanics, in: Pittman Monographs and Surveys in Pure and Applied Mathematics, Vol. 77, Longman, New York, 1995. ##[15] Renardy, M., and Wang, X., “Boundary layers for the upper convected Maxwell fluid”, J. NonNewtonian Fluid Mech., Vol. 189, 2013, pp. 14–18. ##[16] Renardy, M., “High Weissenberg number boundary layers for the upper convected Maxwell fluid”, J. NonNewtonian Fluid Mech., Vol. 68, 1997, pp. 125132. ##[17] Hagen, T., and Renardy, M., “Boundary layer analysis of the Phan–Tien–Tanner and Giesekus model in high Weissenberg number flow”, J. NonNewtonian Fluid Mech., Vol. 73, 1997, pp. 181–189. ##[18] Renardy, M., “Prandtl boundary layers for the PhanThien Tanner and Giesekus fluid”, Z. Angew. Math. Phys., Vol. 66, 2014, pp. 1061 1070. ##[19] Renardy, M., “Wall Boundary Layers for Maxwell Liquids”, Arch. Rational Mech. Anal., Vol. 152, 2000, pp. 93–102. ##[20] Renardy, M. and Wang, X., “Wellposedness of boundary layer equations for timeDependent flow of NonNewtonian fluids”, J. Math. Fluid Mech., Vol. 16, 2014, pp. 179–191 ##[21] Renardy, M., “The initial value problem for creeping flow of the upper convected Maxwell fluid at high Weissenberg number”, Math. Meth. Appl. Sci., Vol. 38, 2014, pp. 959–965. ##[22] Ogilvie, G. I., Proctor, M. R. E., “On the relation between viscoelastic and magnetohydrodynamic flows and their instabilities”, J. Fluid Mech., Vol. 476, 2003, pp. 389409. ##[23] Bird, R. B., Armstrong, R. C., “Dynamics of polymeric Liquids”, second ed., John Wiley & Sons, New York, 1987, Chap 5. ##[24] [24] Evans, J. D., “Reentrant corner flows of the Upper Convected Maxwell fluid,” Proc. Roy. Soc. A, Vol.461, 2005, pp.117–142. ##[25] Renardy, M.,“A matched solution for corner flow of the upper convected Maxwell fluid”, J. NonNewtonian Fluid Mech.,Vol. 58, 1995, pp. 8389. ##[26] Press, W. H., Teukolsky, S. A., Vetterling, W. T., and Flannery, B. P., Numerical Recipes )in Fortran 77(, 2nd ed., Cambridge University Press, New York, 2007.Chap12. ##]
Investigation of The Effects of Process Parameters on The Welding Line Movement in Deep Drawing of Tailor Welded Blanks
2
2
In this paper, the deep drawing process of tailor welded blanks is simulated using the finite element modelling and verified using the experimental results available in the literature. Then the effect of die and material properties on the welding line movement is investigated. It is seen that the most effective material parameters on weld line movement are different between sheet metal thicknesses and strength coefficient of two welded sheets. Also it is seen that the most effective die parameter on weld line movement is the friction coefficient between punch and blank. Finite element simulations show that in the wall section of the drawn cup, the welding line moves toward the material with smaller thickness and lower strength coefficient while in the bottom of the drawn cup, the welding line moves toward the material with larger thickness, and higher strength coefficient. Based on the results, increasing the friction coefficient between blank and die, decreases the welding line movement considerably.
1

45
52


Ali
Fazli
Department of Mechanical Engineering,
Faculty of Engineering and Technology,
Imam Khomeini International University, Qazvin, Iran
Department of Mechanical Engineering,
Faculty
Iran
a.fazli@eng.ikiu.ac.ir
Deep drawing process
Tailor welded blanks
Welding line movement
[[1] Choi, Y., Heo, Y., Kim, H. Y., Seo, D., “Investigations of weldline movements for the deep drawing process of tailor welded blanks”, Journal of Material Processing Technology, Vol.108, No. 1, 2000, pp. 17. ##[2] Kinsey, B., Liu, Z., Cao, J., “A novel forming technology for tailorwelded blanks”, Journal of Material Processing Technology, Vol. 99, No. 13, 2000, pp. 145153. ##[3] Meinders, T., Van den Berg, A., HueÂtink, J., “Deep drawing simulations of Tailored Blanks and experimental verification”, Journal of Material Processing Technology, Vol. 103, No. 1, 2000, pp. 6573. ##[4] Heo, Y. M., Wang, S. H., et al. “The effect of the drawbead dimensions on the weldline movements in the deep drawing of tailorwelded blanks”, Journal of Material Processing Technology, Vol. 113, No. 13, 2001, pp. 686–691. ##[5] He, S., Wu, X., Hu, S. J., “Formability enhancement for tailorwelded blanks using blank holding force control”, Journal of Manufacturing Science and Engineering: Transaction of ASME, Vol. 125, No. 3, 2003, pp. 461–467. ##[6] Kinsey, B. L., Cao, J., “An Analytical Model for Tailor Welded Blank Forming”, Journal of Manufacturing Science and Engineering: Transaction of ASME, Vol. 125, No. 2, 2003, pp. 344–351. ##[7] Bravar, M. N., Kinsey, B. L., “Analytical determination of initial weld line position for tailor welded blank forming”, North American Manufacturing Research Institution of SME, Vol. 32, No. 1, 2004, pp. 597–604. ##[8] Ku, T. W., Kang B. S., Park H. J., “Tailored blank design and prediction of weld line movement using the backward tracing scheme of finite element method”, International Journal of Advanced Manufacturing Technology, Vol. 25, No. 1, 2005, pp. 17–25. ##[9] Chan, L. C., Cheng, C. H., Chan, S. M., Lee, T. C., Chow, C. L., “Formability Analysis of TailorWelded Blanks of Different Thickness Ratios”, Journal of Manufacturing Science and Engineering: Transaction of ASME, Vol. 127, No. 4, 2005, pp. 743–751. ##[10] Padmanabhan, R., Baptista, A. J., Oliveira, M. C., Menezes, L. F., “Effect of anisotropy on the deepdrawing of mild steel and dualphase steel tailorwelded blanks”, Journal of Material Processing Technology, Vol. 184, No. 13, 2007, pp. 288–293. ##[11] Tang, B. T., Zhao, Z., Yu, S., Chen, J., Ruan, X. Y., “Onestep FEM based control of welding line movement for tailorwelded blanks forming”, Journal of Material Processing Technology, Vol. 187–188, 12 June 2007, pp. 383–386. ##[12] Wang, L. J., Wang, G. D., Liu, X. H., Wu, M. T., “Numerical Study on Welding Line Behavior of Deep Drawing TWB Process”, Journal of Iron and Steel Research International, Vol. 14, No. 5, 2007, pp. 3638. ##[13] Padmanabhan, R., Oliveira, M. C., Menezes L. F., Deep drawing of aluminium–steel tailorwelded blank, Materials and Design, Vol. 29, No. 1, 2008, pp. 154–160. ##[14] Padmanabhan, R., Oliveira, M. C., Laurent, H., Alves, J. L., Menezes, L. F., “Study on springback in deep drawn tailor welded blanks”, International Journal of Material Forming, Vol. 2, Aug. 2009, pp. 829832. ##[15] Abbasi, M., Bagheri, B., Ketabchi, M., Haghshenas, D. F., “Application of response surface methodology to drive GTN model parameters and determine the FLD of tailor welded blank”, Computational Materials Science, Vol. 53, No. 1, 2012, pp. 368376. ##[16] Abbasi, M., Ketabchi, M., Labudde, T., Prahl, U., Bleck, W., “New attempt to wrinkling behavior analysis of tailor welded blanks during the deep drawing process”, Materials and Design, Vol. 40, Sep. 2012, pp. 407414. ##[17] Rojek, J., HyrczaMichalska, M., Bokota, A., Piekarska, W., “Determination of mechanical properties of the weld zone in tailorwelded blanks”, Archives of Civil and Mechanical Engineering, Vol. 12, No. 2, 2012, pp. 156162. ##[18] Fazli, A., “Optimum tailorwelded blank design using deformation path length of boundary nodes”, International Journal of Automotive Engineering, Vol. 3, No. 2, 2013, pp. 435445. ##[19] Mohebbi, M. S., Akbarzadeh, A., “Prediction of formability of tailor welded blanks by modification of MK model”, International Journal of Mechanical Sciences, Vol. 61, No. 1, 2012, pp. 4451. ##[20] Safdarian Korouyeh, R., Moslemi Naeini, H., Torkamany, M. J., Liaghat, G. H., “Experimental and theoretical investigation of thickness ratio effect on the formability of tailor welded blank”, Optics & Laser Technology, Vol.51, Oct. 2013, pp. 2431. ## [21] Masumi, H., Masoumi, A., Hashemi, R., Mahdavinejad, R., “A Novel Approach to the Determination of Forming Limit Diagrams for TailorWelded Blanks”, Journal of Materials Engineering and Performance, Vol. 22, No. 11, 2013, pp. 32103221. ##[22] Swift, H. W., “Plastic instability under plane stress”, Journal of the Mechanics and Physics of Solids, Vol. 1, No. 1, 1952, pp. 118. ##]
Numerical Investigation of Laser Bending of Perforated Sheets
2
2
In this work, laser bending of perforated sheets has been investigated numerically. Laser bending of perforated sheets is more complicated than nonperforated sheets due to their complex geometries. In this paper, laser bending of perforated sheets is studied numerically in the form of thermomechanical analysis with ABAQUS/IMPLICIT code. For this purpose, the effects of process and sheet parameters such as laser output power, laser scanning speed, laser beam diameter and the number of punches in the sheet are investigated on the bending angle of laser formed perforated sheet. The results show that the larger punch diameters lead to decrease in bending angle in the laser formed perforated sheets. Also, it is concluded that the bending angle of the perforated sheet is decreased with increasing laser scanning speed. In addition, bending angle is decreased with decreasing laser beam diameter.
1

53
60


Mehdi
Safari
Department of Mechanical Engineering, Arak University of Technology
Department of Mechanical Engineering, Arak
Iran
m.safari@arakut.ac.ir


Mehdi
Ebrahimi
Department of Mecanical Engineering,
Khomein Branch, Islamic Azad University, khomein, Iran
Department of Mecanical Engineering,
Khomein
Iran
ebrahimi.m.iau1245@gmail.com
Bending angle
Laser bending
Perforated sheets
[[1] Chen, D. J., Xiang, Y. B., Wu, S. C., and Li, M. Q., “Application of fuzzy neural network to laser bending to process of sheet metal”, Materials Science and Technology, Vol. 18, No. 2, 2002, pp. 677–680. ##[2] Shen, H., Yao, Z. Q., Shi, Y. J., and Hu, J., “The simulation of temperature field in the laser forming of steel plates”, International Journal of Modeling, Identification and Controlling, Vol. 2, No. 3, 2007, pp. 241–249. ##[3] Vollertsen, F., Geiger, M., and Li, W. M., “FDM and FEM simulation of laser forming: a comparative study”, in: Advanced Technology of Plasticity, Proceedings of the Fourth International Conference on Technology of Plasticity, 1993, pp. 1793–1798. ##[4] Alberti, N., Fratini, L., and Micari, F., “Numerical simulation of the laser bending process by a coupled thermal mechanical analysis”, in: Laser Assisted Net Shape Engineering, Proceedings of the LANE, Vol. 1, 1994, pp. 327–336. ##[5] Alberti, N., Fratini, L., Micari, F., Cantello, M., and Savant, G., “Computer aided engineering of a laser assisted bending processes”, in: Laser Assisted Net Shape Engineering 2, Proceedings of the LANE, Vol. 2, 1997, pp. 375–382. ##[6] Hsiao, Y. C., Shimizu, H., Firth, L., Maher, W., and Masabuchi, K., “Finite element modelling of laser forming”, in: Proceedings of the International Congress on Applications of Lasers and Electrooptics (ICALEO’97), Section A, 1997, pp. 31–40. ##[7] Holzer, H., Arnet, M., and Geiger, M., “Physical and numerical modelling of the buckling mechanism”, in: Laser Assisted Net Shape Engineering, Proceedings of the LANE, Vol. 1, 1994, pp. 379–386. ##[8] Li, W. C., Yao, Y. L., “Numerical and experimental investigation of convex laser forming process”, Journal of Manufacturing Processes, Vol. 3, No. 2, 2001, pp. 73–81. ##[9] Hu, Z., Kovacevic, R., and Labudovic, M., “Experimental and numerical modelling of buckling instability of laser sheet forming”, International Journal of Machine Tools and Manufacture, Vol. 42, No. 13, 2002, pp. 1427–1439. ##[10] Magee, J., Watkins, K. G., Steen, W. M., Calder, N., Sidhu, J., and Kirby, J., “Edge effects in laser forming”, in: Laser Assisted Net Shape Engineering 2, Proceedings of the LANE, Vol. 2, 1997, pp. 399408. ##[11] Bao, J. C., Yao, Y. L., “Analysis and prediction of edge effects in laser bending”, Journal of Manufacturing Science and Engineering, Transactions of the ASME, Vol. 123, 2001, pp. 5361. ##[12] Shen, H., Zhou, J., Shi, Y. J., Yao, Z. Q., and Hu, J., “Varying velocity scan in laser forming of plates”, Materials Science and Technology, Vol. 23, No. 4, 2007, pp. 483486. ##[13] Shen, H., Yao, Z. Q., “Analysis of varying velocity scanning schemes on bending angle in laser forming”, in: International Workshop on Thermal Forming and Welding Distortion, 2008, pp. 215227. ##[14] Safrai, M., Farzin, M., “Experimental and numerical investigation of laser bending of tailor machined blanks”, Optics & Laser Technology, Vol. 48, 2013, pp. 513522. ##[15] Safari, M., Farzin, M., and Ghaei, A., “Investigation into the effects of process parameters on bending angle in the laser bending of tailor machined blanks based on a statistical analysis”, Journal of Laser Applications, Vol. 5, No. 5, 2013, pp. 052001, 110. ##[16] Safari, M., Farzin, M., “A study on laser bending of tailor machined blanks with variousirradiating schemes”, Journal of Materials Processing Technology, Vol. 214, 2014, pp. 112122. ##[17] Shen, H., Shi, Y., and Yao, Zh., “Numerical simulation of the laser forming of plates using two simultaneous scans”, Computational Materials Science, Vol. 37, 2006, pp. 239245. ##]
Experimental Study on Surface Roughness and Flatness in Lapping of AISI 52100 Steel
2
2
Lapping is one of the most important polishing processes which can be used to fabricate flat and smooth surfaces. In this paper, the effect of lapping characteristics and mesh number of abrasive particles are studied on the surface roughness and flatness for the machining of hardened AISI 52100 rings. The most significant lapping characteristics are pressure, lap plate speed and time. Scanning electron microscopy and optical microscopy are used to investigate micro cracks and surface textures. Results showed that surface roughness increased by rising the lapping pressure and plate speed. Also, reduction of the lapping time and mesh number of abrasive particles led to lower surface roughness. Application of lapping process decreased the flatness to 1.2 µm and surface roughness (Ra) from 0.58 to 0.051 µm. The lapping pressure was a significant factor on the surface roughness; and the lapping time was a significant factor on flatness. However, surface roughness increased with rising of mesh number and lapping time, and increased with decreasing the lapping pressure. The minimum surface roughness was 0.051 μm which was obtained in lapping pressure of 7 kPa, lapping speed of 0.164 m/s, time of 15 min and mesh number of 600.The flatness decreased with lapping speed, and reduced with increasing the pressure, mesh number and lapping time.
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61
68


Masoud
Farahnakian
Faculty of Engineering, Mechanical Engineering Department
Najafabad branch, Islamic Azad University, Iran
Faculty of Engineering, Mechanical Engineering
Iran
farahnakian@gmail.com


H.
ُُShahrajabian
Faculty of Engineering, Mechanical Engineering Department
Najafabad branch, Islamic Azad University, Iran
Faculty of Engineering, Mechanical Engineering
Iran
h.shahrajabian@gmail.com
ANOVA
Flatness
Hardened steel
Lapping
Surface Roughness
[[1] Chen, C., Sakai, S., Inasaki, I., “Lapping of advanced ceramics”و Materials and Manufacturing Processes, Vol. 6, No. 2, 1991, pp. 211226. ##[2] Molenda, J., Charchalis, A., “Dependence between workpiece material hardness and face lapping results of steel C45”, Solid State Phenomena., Vol. 220221, 2015, pp. 743748. ##[3] Kim, H. M., Park, G. H., Seo, Y. G., Moon, D. J., Cho, B. J., and Park, J. G., “Comparison between sapphire lapping processes using 2body and 3body modes as a function of diamond abrasive size ”, Wear., Vol. 332333, 2015, pp. 794799. ##[4] Bulsara, V. H., Ahn, Y., Chandrasekar, S., and Farris, T. N., “Polishing and lapping temperature”, Trans. ASME J. Tribol., Vol. 119, 1997, pp. 163170. ##[5] Chang, Y. P., Dornfeld, D. A., “An investigation of the AE signals in the lapping process”, Annals CIRP., Vol. 45, 1996, pp. 331334. ##[6] Uhlmann, E., Ardelt, T., “Influence of kinematics on the face grinding process on lapping machines”, Annals CIRP., Vol. 48, No. 1, 1999, pp. 281284. ##[7] Guzzo, P. L., De Mello, J. D. B., and Daniel, J., “Effect of crystal orientation on lapping and polishing processes of natural quartz, IEEE Trans. Ultrasonics Ferroelectrics Frequency Control”, Vol. 47, 2000, pp. 12171227. ##[8] Mamalis, G., Hidasi, B., Dudas, Z., and Branis, A. S., “On the Lapping Mechanism of Sintered A12O3 Ceramic Surfaces Using Diamonds”, Materials and Manufacturing Processes, Vol. 15, No. 4, 2000, pp. 503520. ##[9] Chang, K. Y., Song, Y. H., and Lin, T. R., “Analysis of Lapping and Polishing of a Gauge Block”, Int J Adv Manuf Tech., Vol. 20, 2002, pp. 414419. ##[10] Tam, H. Y., Cheng, H. B., and Wang, Y. W., “Removal rate and surface roughness in the lapping and polishing of RBSiC optical components,” J Mat Process Tech., Vol. 192193, 2007, pp. 276, 280. ##[11] Belkhir, N., Bouzidd, D., Herold, V., “Correlation between the surface quality and the abrasive grains wear in optical glass lapping”, Tiribology International., Vol. 40, 2007, pp. 498502. ##[12] Deshpande, L. S., Raman, S., Sunanta, O., and Agbaraji, C., “Observations in the flat lapping of stainless steel and bronze”, Wear., Vol. 265, 2008, pp. 105116. ##[13] Mohan, R., Ramesh Babu, N., “Experimental investigations on ice bonded abrasive polishing of copper materials”, Materials and Manufacturing Processes., Vol. 25 , No. 12, 2010, pp. 14621469. ##[14] Mohan, R., Ramesh Babu, N., “Design, development and characterization of ice bonded abrasive polishing process”, International Journal of Abrasive Technology., Vol. 4 , No. 1, 2011, pp. 5776. ##[15] Mohan, R., Ramesh Babu, N., “Ultrafine finishing of metallic surfaces with the ice bonded abrasive polishing process”, Materials and Manufacturing Processes., Vol. 27, 2012, pp. 412419. ##[16] Tsai, M. Y., Chen, C. Y., and He, Y. R., “Polishing Characteristics of Hydrophilic Pad in Chemical Mechanical Polishing Process”, Materials and Manufacturing Processes., Vol. 27, 2012, pp. 650657. ##[17] Tian, Y. B., Zhong, Z. W., Lai, S. T., and Ang, Y. J., “Development of fixed abrasive chemical mechanical polishing process for glass disk substrates”, Int J Adv Manuf Tech., Vol. 68, 2013, pp. 9931000. ##[18] Dong, Z., Cheng, H., “Study on removal mechanism and removal characters for SiC and fused silica by fixed abrasive diamond pellets”, Int J. Mach. Tool Manuf., Vol. 85, 2014, pp. 113. ##[19] Sushil, M., Vinod, K., and Harmesh, K., “Experimental Investigation and Optimization of Process Parameters of Al/SiC MMCs Finished by Abrasive Flow Machining”, Materials and Manufacturing Processes., Vol. 30, 2015, pp. 902911. ##]
Evaluation of γAl2O3/ndecane Nanofluid Performance in Shell and Tube Heat Recovery Exchanger in a Biomass Heating Plant
2
2
The performance of a γAl2O3/ndecane nanofluid shellandtube heat exchanger in a biomass heating plant is analyzed to specify the optimum condition based on the maximum heat transfer rate and performance index for wide range of nanoparticle volume fraction (0–7%). Compared with pure ndecane, the obtained results in this research show that by using γAl2O3/ndecane nanofluid as coolant at optimum values of particle volume concentration for maximum heat transfer rate (ϕ=0.021) and for maximum performance index (ϕ=0.006), the heat transfer rate and pumping power increased by 10.84%, 13.18% and 6.72%, 2.3%, respectively. Increasing particles concentration raises the fluid viscosity, decreases the Reynolds number and consequently decreases the heat transfer coefficient. As a result, determining the optimum value of the particle volume fraction of nanofluid as the working fluid, can improve the performance of shellandtube heat exchangers.
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69
77


Navid
Bozorgan
Abadan Branch, Islamic Azad University,Abadan, Iran
Abadan Branch, Islamic Azad University,Abadan,
Iran
n.bozorgan@gmail.com


Maryam
Shafahi
California State Polytechnic University, Pomona, California, USA
California State Polytechnic University,
Iran
maryam.shafahi@email.ucr.edu
Heat transfer
Nanofluid
pressure drop
Shell and Tube Heat Exchanger
[[1] Choi, S. U. S., Eastman, J. A., “Enhancing thermal conductivity of fluids with nanoparticles”, in ASME Int. Mechanical Congress and Exposition, San Francisco, Calif, USA, 1995. ##[2] Sarkar, J., “Performance of nanofluidcooled shell and tube gas cooler in transcritical CO2 refrigeration systems”, Applied Thermal Engineering, 2011, Vol. 31, No. 1415, pp. 25412548. ##[3] Mohammed, H. A., Bhaskaran, G., Shuaib, N. H. and Saidur, R., “Influence of nanofluids on parallel flow square microchannel heat exchanger performance”, International Communications in Heat and Mass Transfer, 2011, Vol. 38, No. 1, pp. 19. ##[4] Saeedinia, M., AkhavanBehabadi, M. A. and Nasr, M., “Experimental study on heat transfer and pressure drop of nanofluid flow in a horizontal coiled wire inserted tube under constant heat flux”, Experimental Thermal Fluid Science, 2012, Vol. 36, pp. 158168. ##[5] Vajjha, R. S., Das, D. K., and Namburu, P. K., “Numerical study of fluid dynamic and heat transfer performance of Al2O3 and CuO nanofluids in the flat tubes of a radiator”, International Journal of HeatandFluid Flow, 2010, Vol. 31, No. 4, pp. 613621. ##[6] Strandberg, R., Das, Debendra, K., “Finned performance evaluation with nanofluids and convectional heat transfer fluids”, International Journal of Thermal Science, 2010, Vol. 31, No. 4, pp. 613621. ##[7] Anthony B., Kuhry, Paul J. Weimer, “Biological/Electrolytic Conversion of Biomass to Hydrocarbons”, published as US8518680, 2009, US20140038254, Apr 17. ##[8] Yetter, R. A., Risha, G. A. and Son, S. F., “Metal particle combustion and nanotechnology”, Proceedings of the Combustion Institute, 2009, Vol. 32, No. 2, pp. 18191838. ##[9] Jackson, D., Davidson, D. and Hanson, R., “Application of an aerosol shock tube for the kinetic studies of ndodecane/nanoaluminum slurries”, 2008, in: 44th AlAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, Hartford, CT, United States. ##[10] Tyagi, H., Phelan, P. E., Prasher, R., Peck, R., Lee, T., Pacheco, J. R. and Arentzen, P., “Increased hotplate ignition probability for nanoparticleladen diesel fuel”, 2008, Nano Letters, Vol. 8, No. 5, pp. 14101416. ##[11] Pak, B. C., Cho, Y. I., “Hydrodynamic and heat transfer study of dispersed fluids with submicron metallic oxide particles”, Experimental Heat transfer, 1998, Vol. 11, No. 2, pp. 151170. ##[12] Xuan, Y., Roetzel, W., “Conceptions of heat transfer correlation of nanofluids”, International Journal of HeatandMass Transfer, 2000, Vol. 43, No. 19, pp. 37013707. ##[13] Corcione, M., “Empirical correlating equations for predicting the effective thermal conductivity and dynamic viscosity of nanofluids”, Energy Conversion Management, 2011, Vol. 52, No. 1, pp. 789–793. ##[14] Eduardo, Cao, “Heat transfer in process engineering”, New York: McGrawHill, 2010. ##[15] Li, Q., Xuan, Y., “Convective heat transfer and flow characteristics of Cu–water nanofluid”, Science in China Series E: Technological Sciences, 2002, Vol. 45, No. 4, pp. 408416. ##[16] Incropera, F. P., DeWitt, D. P., “Introduction to Heat Transfer”, fourth ed. John Wiley and Sons, 2002. ##[17] Esfe, M. H., Saedodin, S. and Mahmoodi, M., “Experimental studies on the convective heat transfer performance and thermophysical properties of MgOwater nanofluid under turbulent flow”, Experimental Thermal and Fluid Science, 2014, Vol. 52, pp. 6878. ##[18] Jwo, C. S., Jeng, L. Y., Teng, T. P. and Chen, C. C., “Performance of overall heat transfer in multichannel heat exchanger by alumina nanofluid”,Journal of Alloys and Compounds, 2010, Vol. 504, pp. S385S388. ##[19] Lelea, D., “The performance evaluation of Al2O3/water nanofluid flow and heat transfer in microchannel heat sink”, International Journal of Heat and Mass Transfer, 2011, Vol. 54, Issue 1718, pp. 38913899. ##[20] Pantzali, M. N., Mouza, A. A. and Paras, S. V., “Investigating the efficacy of nanofluids as coolants in plate heat exchangers (PHE)”, Chemical Engineering Science, 2009, Vol. 64, Issue 14, pp. 32903300. ##[21] Kabeel, A. E., Abou El Maaty, T. and El Samadony Y., “The effect of using nanoparticles on corrugated plate heat exchanger performance”, Applied Thermal Engineering, 2013, Vol. 52, Issue 1, pp. 221229. ##[22] Tiwari, A. K., Ghosh, P., and Sarkar, J., “Performance comparison of the plate heat exchanger using different nanofluids”, Experimental Thermal and Fluid Science, 2013, Vol. 49, pp. 141151. ##[23] Tiwari, A. K., Ghosh, P., and Sarkar, J., “Particle concentration levels of various nanofluids in plate heat exchanger for best performance”, International Journal of Heat and Mass Transfer, 2015, Vol. 89, pp. 11101118. ##]
Investigation on Stress Distribution of Functionally Graded Nanocomposite Cylinders Reinforced by Carbon Nanotubes in Thermal Environment
2
2
In this paper, stress and displacement fields of functionally graded (FG) nanocomposite cylinders reinforced by carbon nanotubes (CNTs) subjected to internal pressure and in thermal environment are investigated by finite element method. The nanocomposite cylinders are combinations of singlewalled carbon nanotubes (SWCNTs) and isotropic matrix. Material properties are estimated by a micro mechanical model (Rule of mixture), using some effective parameters. In this simulation, an axisymmetric model is used; uniform and four kinds of linear functionally graded (FG) distributions of CNTs along the radial direction is assumed, in order to study the stress distributions. Effects of the kind of distribution and volume fraction of CNT and also, thermal environment, and geometry dimension of cylinder are investigated on the stress and displacement distributions of the FG nanocomposite cylinders. It is shown that, CNTs distribution and environment temperature are important factors on the stresses distribution of the nanocomposite cylinders.
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79
91


Mohammad morad
Sheikhi
Department of Mechanical Engineering,
Shahid Rajaee Teacher Training University (SRTTU), Tehran, Iran
Department of Mechanical Engineering,
Shahid
Iran
m.sheikhi@srttu.edu


Hamidreza
Shamsolhoseinian
Department of Mechanical Engineering,
Shahid Rajaee Teacher Training University (SRTTU), Tehran, Iran
Department of Mechanical Engineering,
Shahid
Iran


Rasool
Moradi dastjerdi
Young Researchers and Elite Club,
Khomeinishahr Branch, Islamic Azad University, Khomeinishahr, Iran
Young Researchers and Elite Club,
Khomeinishahr
Iran
rasoul.moradi@iaukhsh.ac.ir
Carbon nanotubes
Finite Element Method
Functionally graded
Nanocomposite cylinders
stress distribution
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M., “Thermoelastic analysis of functionally graded carbon nanotubereinforced composite plate using theory of elasticity”, Composite Structures,Vol. 106, 2013, pp. 873–881. ##[20] MoradiDastjerdi, R., Foroutan, M., Pourasghar, A., and SotoudehBahreini R., “Static analysis of functionally graded carbon nanotubereinforced composite cylinders by a meshfree method”, Journal of Reinforced Plastic and Composites, Vol. 32, 2013, pp. 593601. ##[21] MoradiDastjerdi, R., Foroutan, M., and Pourasghar, A., “Dynamic analysis of functionally graded nanocomposite cylinders reinforced by carbon nanotube by a meshfree method”, Materials and Design, Vol. 44, 2013, pp. 25666. ##[22] MoradiDastjerdi, R., Sheikhi, M. M., and Shamsolhoseinian, H. R., “Stress Distribution in Functionally Graded Nanocomposite Cylinders Reinforced by Wavy Carbon Nanotube”, Int J of Advanced Design and Manufacturing Technology, Vol. 7, 2014, pp. 4354. ##[23] Jam, J. 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S., “Nonlinear bending of functionally graded carbon nanotube reinforced composite plates in thermal environments,” Composite Structures, Vol. 91, 2009, pp. 9–19 ##[29] Li, X. F., Peng, X. L., “A pressurized functionally graded hollow cylinder with arbitrarily varying material properties”, Journal Elasticity, Vol. 96, 2009, pp. 81–95. ##[30] Hetnarski, R. B., Eslami M. R., “Thermal Stresses–Advanced Theory and Applications”, Springer, Solid Mechanics and its applications, 2009, Chaps. 4. ##]
Effect of Welding Parameters on Microstructure and Mechanical Properties of Friction Stir Spot Welded of Titanium Alloy TiAl6V4
2
2
In this study, friction stir spot welding (FSSW) is applied to join the TiAl6V4 titanium alloy with 1.5 mm thickness and then the effect of rotational speed and tool dwell time on microstructure and mechanical properties is investigated. In this regard, the speed of the tool rotation was considered as 800, 1000, and 1200 rpm, as well as the tool dwell time was set at 7 and 12s. Microstructural evaluation was carried out using optical microscopy (OM) and scanning electron microscopy (SEM). In addition, tensileshear and hardness studies were performed to analyze mechanical properties. The obtained results from microstructural evaluation show that the welded joints consist of two regions, namely the SZ and the HAZregions. Additionally, microstructure of the SZregion was identified in the form of α/β layer within the initial βphase. The results of tensile/shear tests and microhardness test indicated that the joint strength and hardness are enhanced with increasing the rotational speed and dwell time. The tensile/shear strength is increased from 2.7 to 15 KN with increasing the rotational speed at constant dwell time of 7s, and also is increased from 7.3 to 17.25 KN with increasing the rotational speed at constant dwell time of 12s. The maximum tensile/shear strength was achieved for the welded joint with the dwell time of 12s and rotational speed of 1250 rpm. The hardness of SZ, HAZ regions and base metal are measured around 380 to 420, 340 to 380, and 300 to 340, respectively.
1

93
100


Saeid
Nader
Department of Materials Engineering,
Najafabad Branch, Islamic Azad University, Najafabad, Iran
Department of Materials Engineering,
Najafabad
Iran
s.nader@yahoo.com


Masoud
Kasiri Asgarani
Department of Materials Engineering,
Najafabad Branch, Islamic Azad University, Najafabad, Iran
Department of Materials Engineering,
Najafabad
Iran
m.kasiri@gmail.com


kamran
amini
Department of Mechanical Engineering,
Tiran Branch, Islamic Azad University, Isfahan, Iran
Department of Mechanical Engineering,
Tiran
Iran
k.amini@iaumajlesi.ac.ir


Morteza
Shamanian
Department of Mechanical Engineering,
Isfahan University of Technology, Isfahan, Iran
Department of Mechanical Engineering,
Isfahan
Iran
m_shamanian@gmail.com
Dwell time
Friction stir spot welding
Rotation speed
Titanium alloy
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