Shahid Chamran University of Ahvaz
Journal of Applied and Computational Mechanics
2383-4536
3
4
2017
10
01
Multi-boiling Heat Transfer Analysis of a Convective Straight Fin with Temperature-Dependent Thermal Properties and Internal Heat Generation
229
239
EN
Gbeminiyi
Sobamowo
Department of Mechanical Engineering, University of Lagos, Akoka, Lagos, Nigeria
mikegbeminiyi@gmail.com
Ola
Kamiyo
Department of Mechanical Engineering, University of Lagos, Akoka, Lagos, Nigeria
okamiyo@unilag.edu.ng
10.22055/jacm.2017.12637
In this study, by using the finite volume method, the heat transfer in a convective straight fin with temperature-dependent thermal properties and an internal heat generation under multi-boiling heat transfer modes are analyzed. In this regard, the local heat transfer coefficient is considered to vary within a power-law function of temperature. In the present study, the coexistence of all the boiling modes is taken into consideration. The developed heat transfer models and the corresponding numerical solutions are used to investigate the effects of various thermo-geometric parameters on the thermal performance of the longitudinal rectangular fin. The results shows that the fin temperature distribution, the total heat transfer, and the fin efficiency are significantly affected by the thermo-geometric parameters of the fin and the internal heat generation within the fin. The obtained results can provide a platform for improvements in the design of the fin in the heat transfer equipment.
Multi-boiling heat transfer,Convective straight fin,Finite volume method,Temperature-dependent properties,Internal heat generation
http://jacm.scu.ac.ir/article_12637.html
http://jacm.scu.ac.ir/article_12637_5df64def27b178be1e7fe495cbc745e2.pdf
Shahid Chamran University of Ahvaz
Journal of Applied and Computational Mechanics
2383-4536
3
4
2017
10
01
Effect of Variable Thermal Expansion Coefficient and Nanofluid Properties on Steady Natural Convection in an Enclosure
240
250
EN
Esmaeil
Ghahremani
Department of Energy Engineering and Physics, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Islamic Republic of Iran
eghahremani86@gmail.com
Reihaneh
Ghaffari
University of Calgary, Canada
reihaneh.ghaffari@ucalgary.ca
Hossein
Ghadjari
Department of Energy Engineering and Physics, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Islamic Republic of Iran
Javad
Mokhtari
Department of Mathematics, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran
javadmokhtari67@gmail.com
10.22055/jacm.2017.21451.1099
Steady state natural convection is numerically investigated in an enclosure using variable thermal conductivity, viscosity and thermal expansion coefficient of Al2O3–water nanofluid. This study has been conducted for a wide range of Rayleigh numbers (103≤ Ra ≤ 106), concentrations of nanoparticles (0% ≤ Φ ≤ 7%), enclosure aspect ratios (0.5 ≤ AR ≤ 2) and temperature differences between the cold and the hot walls (1≤ ∆T≤ 30). The main idea in this study is about the effect of temperature on natural convection pattern of nanofluid by changing nanoparticles concentration. Also, changing thermal expansion coefficient with temperature is considerd in this study which will have significant effects on natural convection and has not been considerd before. In low Rayleigh numbers (Ra= 103) and for cavities with AR≥1, the pattern shown in the average Nusselt number versus volume fraction of nanoparticles diagram deteriorates by increasing ∆T. However, for other cases, increasing ∆T has a positive effect on Nu-Φ diagram. The actual Nuselt number curve depicts that dispersing nanoparticles in base fluid deteriorate natural convection heat transfer which is in a good agreement with experimental works.
Nanofluid,Natural convection,variable property
http://jacm.scu.ac.ir/article_12714.html
http://jacm.scu.ac.ir/article_12714_55c5dafae1098d72acb22f407106098c.pdf
Shahid Chamran University of Ahvaz
Journal of Applied and Computational Mechanics
2383-4536
3
4
2017
10
01
Investigation on the Ultrasonic Tube Hydroforming in the Bulging Process Using Finite Element Method
251
257
EN
Mehdi
Zarei
Department of Mechanical Engineering, Tarbiat Modares University (TMU),
Tehran 14115-143, Iran
mehdi.zarei@modares.ac.ir
Gholam
Faghani
Department of Mechanical Engineering, Khatam Al Anbia Air Defense University,Tehran, Iran,178183513, Iran
g.r.faghani@stud.nit.ac.ir
Mahmood
Farzin
Department of Mechanical Engineering, Isfahan University of Technology
, Isfahan 84156-83111, Iran
farzin@cc.iut.ac.ir
Mohammad
Mashayekhi
Department of Mechanical Engineering, Isfahan University of Technology
, Isfahan 84156-83111, Iran
mashayekhi@cc.iut.ac.ir
10.22055/jacm.2017.21852.1119
In ultrasonic tube hydroforming, the tube is hydro formed while the ultrasonic vibration is applied to the die. Prior studies provide experimental proof that ultrasonic tube hydroforming reduces corner radius, improves lubrication and uniform thickness. Use of ultrasonic vibration can decrease friction at the tube-die interface. Few attempts have been made to analyze the wire drawing while the ultrasonic vibrations were also applied during the processes. A detailed analysis and understanding of the mechanism of improvement is not possible with conventional experimental observation because the ultrasonic vibration processing phenomenon occurs at high speed. Therefore, we attempt to understand the processing mechanism of ultrasonic tube hydroforming using the finite element method (FEM).ABAQUS was used for the FEM. Forming force and formability in tube hydroforming analyzed. From these studies, we quantitatively clarified the mechanism of improved formability characteristics, such as decreased forming load and increasing bulging diameter.
tube hydroforming,ultrasonic oscillation,Finite Element Method,bulging process
http://jacm.scu.ac.ir/article_13039.html
http://jacm.scu.ac.ir/article_13039_18ebd89164a757f250746d50879867ef.pdf
Shahid Chamran University of Ahvaz
Journal of Applied and Computational Mechanics
2383-4536
3
4
2017
10
01
Flow and Heat Transfer Analysis of the Sodium Alginate Conveying Copper Nanoparticles between Two Parallel Plates
258
266
EN
Akin T.
Akinshilo
Mechanical Engineering Department; University of Lagos, Akoka-Yaba, 100001, Nigeria
ta.akinshilo@gmail.com
Joseph O.
Olofinkua
Mechanical Engineering Department; University of Lagos, Akoka-Yaba, 100001, Nigeria
josepholofinkua@yahoo.com
Osamudiamen
Olaye
Mechanical Engineering Department; University of Benin, Benin City, 300271, Nigeria
osamudiamen.olaye@uniben.edu
10.22055/jacm.2017.21514.1105
In this study, the steady incompressible flow of a non-Newtonian sodium alginate (SA) fluid conveying copper nanoparticles (Cu) which flow within two vertical parallel plates is investigated by using the homotopy perturbation analytical scheme to solve the coupled nonlinear ordinary equations arising from the mechanics of the fluid. The developed analytical solutions are used to investigate the effect of the fluid flow and heat transfer parameters such as the nanoparticle concentration, the non-Newtonian parameter and the viscosity variation parameter. The obtained analytical results as compared to existing works in literature are in satisfactory agreements. Moreover, the results obtained from the present study can be used for further analysis of the behavior of the sodium alginate in applications such as food processing and chemical and pharmaceutical industries.
Sodium alginate,copper,Parallel plates,Perturbation,Nano fluid,Non-Newtonian
http://jacm.scu.ac.ir/article_12773.html
http://jacm.scu.ac.ir/article_12773_4e9476351be085fb2c60f039426d4c33.pdf
Shahid Chamran University of Ahvaz
Journal of Applied and Computational Mechanics
2383-4536
3
4
2017
10
01
A Method for Determination of the Fundamental Period of Layered Soil Profiles
267
273
EN
Duygu
Ozturk
Department of Civil Engineering., Faculty of Engineering, University of Ege, Bornova, Izmir, Turkey
duygu.ozturk@ege.edu.tr
K. Burak
Bozdogan
Department of Civil Engineering., Faculty of Engineering, University of Canakkale Onsekiz Mart, Canakkale, Turkey.
kbbozdogan@comu.edu.tr
10.22055/jacm.2017.21810.1116
In this study, a method is proposed to determine the fundamental period of layered soil profiles. A model considering the layered soil as shear type structure is used. At first, the soil profile is divided into substructures. Then, the stiffness matrices of the substructures considered as the equivalent shear structures are assembled according to the Finite Element Method. Thereinafter, the stiffness matrices of the substructures are transformed into the Modified Finite Element Transfer Matrices, which take part in the literature. Finally, the system matrix is assembled using matrices of the substructures. The proposed method provides reduction in the size of the matrix. Therefore, analysis time is remarkably reduced. At the end of the study, the accuracy of the method is presented by the examples. Consequently, the proposed method offers a practical method for determination of the fundamental period of the soil.
Finite element,Soil profile,fundamental period,Transformation,Transfer matrix
http://jacm.scu.ac.ir/article_13034.html
http://jacm.scu.ac.ir/article_13034_032bcb82acb6d5cc6f34dc9aaa2cca89.pdf
Shahid Chamran University of Ahvaz
Journal of Applied and Computational Mechanics
2383-4536
3
4
2017
10
01
Bending, Buckling and Vibration of a Functionally Graded Porous Beam Using Finite Elements
274
282
EN
Noha
Fouda
Production Engineering and mechanical Design Dept, Mansoura University
Al Mansurah, Egypt
nfooda@gmail.com
Tawfik
El-midany
Production Engineering and mechanical Design Dept, Mansoura University
Al Mansurah, Egypt
tawfikm@gmail.com
A. M.
Sadoun
Mechanical Engineering Dept, King Abdulaziz University, Jeddah, Saudi Arabia
AND
Mechanical Design and Production Eng. Dept., Zagazig University,
Al Zagazig, Egypt
aymansadoun76@gmail.com
10.22055/jacm.2017.21924.1121
This study presents the effect of porosity on mechanical behaviors of a power distribution functionally graded beam. The Euler-Bernoulli beam is assumed to describe the kinematic relations and constitutive equations. Because of technical problems, particle size shapes and micro-voids are created during the fabrication which should be taken into consideration. Two porosity models are proposed. The first one describes properties in the explicit form as linear functions of the porosity parameter. The second is a modified model which presents porosity and Young’s modulus in an implicit form where the density is assumed as a function of the porosity parameter and Young’s modulus as a ratio of mass with porosity to the mass without porosity. The modified proposed model is more applicable than the first model. The finite element model is developed to solve the problem by using the MATLAB software. Numerical results are presented to show the effects of porosity on mechanical behaviors of functionally graded beams.
Mechanical Behaviors,Porous material,functionally graded material,Beam Analysis,Finite Element Method
http://jacm.scu.ac.ir/article_12817.html
http://jacm.scu.ac.ir/article_12817_a580c4a4f6f4b08d0a2c876ed28fe3ed.pdf
Shahid Chamran University of Ahvaz
Journal of Applied and Computational Mechanics
2383-4536
3
4
2017
10
01
Finite Element Analysis for CFST Columns under Blast Loading
283
292
EN
Peyman
Beiranvand
Department of Civil Engineering, Lorestan University, Khorram abad, Iran
peyman51471366@gmail.com
Fereydoon
Omidinasab
Department of Civil Engineering, Lorestan University, Khorram abad, Iran
omidinasab@gmail.com
Marziye
Sadate Moayeri
Lecturer, Civil Engineering faculty, Borujerd Branch, Islamic Azad University, Iran
a.moayeri1990@yahoo.com
Shahpoor
Mehdipour
Department of Civil Engineering
Arak Branch, Islamic Azad University, Iran
mehdipoor1349@gmail.com
Mohammad
Zarei
Department of Civil engineering, Imam Khomeini international university, Qazvin, Iran
mohammadzarei959@yahoo.com
10.22055/jacm.2017.21992.1122
The columns of frame structures are the key load-bearing components and the exterior columns are susceptible to attack in terrorist blasts. When subjected to blast loads, the columns would suffer a loss of bearing capacity to a certain extent due to the damage imparted which may lead to their collapse and even cause the progressive collapse of the whole structure . The concrete-filled steel columns have been extensively used in the world due to the existence of all suitable characteristics of concrete and steel, more ductility, increasing concrete confinement using the steel wall, the large energy-absorption capacity and the appropriate fire behavior. In the present study, the concrete-filled steel square columns have been simulated under the influence of the blast load using the ABAQUS software. These responses have been compared for scaled distances based on the distance to the source and the weight of the explosive material. As a result, it can be seen that although concrete deformation has been restricted using the steel tube, the inner layer of concrete has been seriously damaged and the column displacement has been decreased by increasing the scaled distance. We also concluded that the concrete-filled steel columns have the high ductility and the blast resistance.
Blast Load,Concrete-Filled Steel Columns,Finite Element Analysis
http://jacm.scu.ac.ir/article_12816.html
http://jacm.scu.ac.ir/article_12816_61de52714fc3fee52a1fac894b72a08b.pdf
Shahid Chamran University of Ahvaz
Journal of Applied and Computational Mechanics
2383-4536
3
4
2017
10
01
Modified U-Slot Stacked Micro-Strip Patch Antenna for Ultra-Wideband Applications in S Band, C Band and X Band
293
301
EN
Monika
Surana
Poorima College of Engineering, Jaipur, Rajasthan, India
suranamonika@gmail.com
Amit
Kumar
Jain
Poornima College Of Engineering, Jaipur
jain.2102@gmail.com
10.22055/jacm.2017.12638
The U-slot micro-strip patch antennas were originally developed for bandwidth broadening applications. This study presents a transmission line feed to modify the U-slot stacked rectangular micro-strip patch antenna for Ultra-Wide Band (UWB) communications. The modified antenna has a U-cut loaded with parallel slits and corner slots and is printed on a dielectric substrate of FR4 with relative permittivity (εr) of 4.4, the thickness of 1.59 mm and the tangent loss of 0.025. The results show that the proposed antenna achieves an impedance bandwidth of 11.55 GHz (2.1 – 13.65 GHz) with the return loss < (-10) dB. This antenna can be employed for ultra-wideband applications in S Band, C Band and X Band. The proposed patch antenna is designed and simulated by using IE3D 14.0 software. Simulation results are presented in terms of the resonant frequency, the return loss, VSWR, the impedance bandwidth and the impedance matching.
UWB antenna,VSWR,IE3D & Return Loss
http://jacm.scu.ac.ir/article_12638.html
http://jacm.scu.ac.ir/article_12638_eb623a5a8e7d4b143d2c81d82738d370.pdf