eng
Shahid Rajaee Teacher Training University (SRTTU)
Journal of Computational & Applied Research in Mechanical Engineering (JCARME)
2228-7922
2251-6549
2013-09-11
3
1
1
11
10.22061/jcarme.2013.55
55
Effect of welding parameters on pitting corrosion rate of pulsed current micro plasma arc welded AISI 304L sheets in 1N HCl
Kondapalli Siva Prasad
1
Chalamalasetti Srinivasa Rao
2
Damera Nageswara Rao
3
Assistant Professor, Department of Mechanical Engineering, Anil Neerukonda Institute of Technology & Sciences , Visakhapatnam, India
Associate Professor, Department of Mechanical Engineering, AU College of Engineering, Andhra University, Visakhapatnam, India
Vice Chancellor, Centurion University of Technology & Management, Odisha, India
Austenitic stainless steel sheets have gained wide acceptance in the fabrication of components, which require high temperature resistance and corrosion resistance such as metal bellows used in expansion joints in aircraft, aerospace and petroleum industries. In the case of single pass welding of thinner sections of this alloy, Pulsed Current Micro Plasma Arc Welding (PCMPAW) has been found beneficial due to its advantages over the conventional continuous current process. This paper highlighted development of empirical mathematical equations using multiple regression analysis, correlating various process parameters to pitting corrosion rates in PCMPAW of AISI 304L sheets in 1 Normal HCl. The experiments were conducted based on a five factor, five level central composite rotatable design matrix. The model adequacy was checked by Analysis of Variance (ANOVA). The main effects and interaction effects of the welding process parameters on pitting corrosion rates of the welded joints were studied using surface and contour plots. From the contour plots, it was understood that peak current was the most influencing factor on the pitting corrosion rate. The optimum pitting corrosion rate was achieved at peak current of 6 Amperes, base current of 4 Amperes, pulse rate of 40 pulses/second and pulse width of 50 % .
http://jcarme.sru.ac.ir/article_55_38876825d45be23e70f98f62f8508e52.pdf
AISI 304L
Pulsed current
Micro plasma arc welding
Pitting corrosion
eng
Shahid Rajaee Teacher Training University (SRTTU)
Journal of Computational & Applied Research in Mechanical Engineering (JCARME)
2228-7922
2251-6549
2013-09-11
3
1
13
25
10.22061/jcarme.2013.56
56
Study on buckling of steel cylindrical shells with an elliptical cutout under combined loading
Abdolhossein Fereidoon
1
Kamal Kolasangiani
2
Amin Akbarpour
3
Mahmoud Shariati
4
Faculty of Mechanical Engineering, Semnan University, Semnan, Iran
Department of Mechanical Engineering, Shahrood University of Technology, Shahrood, Iran
Department of Mechanical Engineering, Semnan Branch, Islamic Azad University, Semnan, Iran
Department of Mechanical Engineering, Ferdowsi University of Mashhad, Mashhad, Iran
In this paper, simulation and analysis of thin steel cylindrical shells with elliptical cutouts under oblique loading were studied using finite element method. First, the numerical results were validated by the results of experimental test performed by an INSTRON 8802 servo hydraulic machine. Also, the effect of cutout angle (θ), cutout size, cutout position (L0/L) and cutout aspect ratios (b/a) were investigated, where parameter (a) shows size of the cutout along longitudinal axis of the cylinder, parameter (b) is size of the cutout in circumferential direction of the cylinder on the buckling and post-buckling behavior of cylindrical shells with finite element method. It can be concluded that increasing width of the cutout extremely decreased the buckling load while the cutout height was constant. Moreover, changing position of the cutout from the mid-height of the shell toward the edges increased the buckling load.
http://jcarme.sru.ac.ir/article_56_96cf0b7f4c5f2be71d6144df8be4fc09.pdf
Buckling
cutout
combined loading
eng
Shahid Rajaee Teacher Training University (SRTTU)
Journal of Computational & Applied Research in Mechanical Engineering (JCARME)
2228-7922
2251-6549
2013-09-11
3
1
27
39
10.22061/jcarme.2013.57
57
Multi-objective optimization and analysis of electrical discharge machining process during micro-hole machining of D3 die steel employing salt mixed de-ionized water dielectric
I. Shivakoti
1
G. Kibria
2
S. Diyaley
3
B. B. Pradhan
4
Mechanical Engineering Department, Sikkim Manipal Institute of Technology (SMIT), Mazitar,Sikkim-737136, India
Mechanical Engineering Department, Aliah University Kolkata-700091, India
Mechanical Engineering Department, Sikkim Manipal Institute of Technology (SMIT), Mazitar,Sikkim-737136, India
Mechanical Engineering Department, Sikkim Manipal Institute of Technology (SMIT), Mazitar,Sikkim-737136, India
Correct selection of manufacturing condition is one of the most important aspects which should be considered in the majority of manufacturing processes, particularly in the process related to advanced machining process like electrical discharge machining. In electrical discharge machining (EDM), dielectric fluid plays an important role since machining characteristics are greatly influenced by the nature or characteristics of employed dielectric. Moreover, adding various types of abrasives or salt in the fluid at different concentrations also affect the machining performance because of changing dielectric strength property. The present paper addressed the influence of NaNO3 mixed de-ionized water as a dielectric fluid on micro-hole machining performance criteria such as material removal rate (MRR), tool wear rate (TWR), overcut (OC) and taper during machining of D3 die steel plate.
http://jcarme.sru.ac.ir/article_57_5cff18ca54922b3a0cf5ba8ffaad9156.pdf
Electric discharge machining
De-ionized water
D3 die steel
Dielectric fluid
Taguchi method
eng
Shahid Rajaee Teacher Training University (SRTTU)
Journal of Computational & Applied Research in Mechanical Engineering (JCARME)
2228-7922
2251-6549
2013-09-11
3
1
41
52
10.22061/jcarme.2013.58
58
Investigation of electrokinetic mixing in 3D non-homogenous microchannels
J. Jamaati
1
H. Niazmand
2
M. Renksizbulut
3
Razi University, Department of Mechanical Engineering, Kermanshah, Iran
Ferdowsi University of Mashhad, Department of Mechanical Engineering, Mashhad, Iran
University of Waterloo, Department of Mechanical & Mechatronics Engineering, Waterloo, Canada
A numerical study of 3D electrokinetic flows through micromixers was performed. The micromixers considered here consisted of heterogeneous rectangular microchannels with prescribed patterns of zeta-potential at their walls. Numerical simulation of electroosmotic flows within heterogeneous channels requires solution of the Navier-Stokes, Ernest-Plank and species concentration equations. It is known that a 3D solution of these equations is computationally very intensive. Therefore, the well-known Helmholtz-Smoluchowski model is often used in numerical simulation of electroosmotic flows. According to 2D studies on electrokinetic mixing inside heterogeneous channels, existence of vortices within the flow field always increases mixing performance. Hence, it may be expected that similar observations pertain to mixing in 3D flows as well. However, investigations on 3D micromixers identified situations in which existence of vortices had little or no significant benefit to the mixing performance. Findings of the present work indicated degree of flow asymmetry as a key parameter for the mixing performance. Since 3D flows are more capable of developing asymmetrical flow patterns, they are expected to have better mixing performance than their 2D counterparts. The results presented here for different 3D cases showed that mixing performance could be improved significantly depending on the alignment of vortex plane relative to the mixing interface of the fluids. These observations confirmed that 2D simulations of mixing could not fully explain behavior of passive micromixers.
http://jcarme.sru.ac.ir/article_58_f437ca41ccf57cfbc939fb377da774ab.pdf
Mixing
Electroosmotic
Helmholtz-Smoluchowski model
Non-homogeneous
eng
Shahid Rajaee Teacher Training University (SRTTU)
Journal of Computational & Applied Research in Mechanical Engineering (JCARME)
2228-7922
2251-6549
2013-09-11
3
1
53
62
10.22061/jcarme.2013.59
59
Chemical reaction and radiation effects on MHD free convection flow through a porous medium bounded by a vertical surface with constant heat and mass flux
T. Sudhakar Reddy
1
M. C. Raju
2
S. V. K. Varm
3
Department of Mathematics, Priya Darshini Institute of Technology, Tirupati, Andhra Pradesh, India-517507
Department of Mathematics, Annamacharya Institute of Technology and Sciences Rajampet (Autonomous), Rajampet, Kadapa District, Andhra Pradesh, India- 516126
Department of Mathematics, Sri Venkateswara University, Tirupati, Andhra Pradesh, India – 517502
In the present paper, an analysis was carried out to investigate effects of radiation on a free convection flow bounded by a vertical surface embedded in a porous medium with constant suction velocity. It was under the influence of uniform magnetic field in the presence of a homogenous chemical reaction and viscous dissipation with constant heat and mass flux. The non-dimensional governing equations were solved analytically and the expressions were found for velocity, temperature and concentration fields. Also, the expression for skin friction near the plate was derived and the results were discussed in a table.
http://jcarme.sru.ac.ir/article_59_3bdd28f5c456919896e7ec71b54a0dbe.pdf
MHD
free convection
Vertical surface
Constant heat and mass flux
eng
Shahid Rajaee Teacher Training University (SRTTU)
Journal of Computational & Applied Research in Mechanical Engineering (JCARME)
2228-7922
2251-6549
2013-09-11
3
1
63
74
10.22061/jcarme.2013.60
60
Free convection in a 3D chamber with local cooling and heating
M. Nasiri
1
B. Ghasemi
2
Shahrekord University, Department of Mechanical Engineering, Shahrekord, Iran
Shahrekord University, Department of Mechanical Engineering, Shahrekord, Iran
This paper modeled heating air of a room through examining free convection in a 3D chamber. The chamber had cold and hot sources with Tc and Th temperatures, respectively. Its other walls were adiabatic. This study aimed at predicting effect of temperature difference, displacement of hot and cold sources and their aspect ratio on flow field, temperature and heat transfer rate. To conduct the study, mass conservation, momentum and energy equations were applied in laminar and 3D states while assuming fluid constant properties, except density, in the power of buoyancy (Boussinesq approximation). Final difference method (FDM) was used for numerical solution of the governing equations based on the volume control and SIMPLE algorithm. According to the modeling results, the most favorable temperature distribution in the chamber (room) was obtained when the heat source (radiator) was located on the wall under the cold source (window). Reducing the distance between the two sources would result in increasing heat transfer from the heating sources.
http://jcarme.sru.ac.ir/article_60_2d71d631e7bd9f18f6cec584e132222b.pdf
free convection
3D chamber
Nusselt number
Rayleigh number
eng
Shahid Rajaee Teacher Training University (SRTTU)
Journal of Computational & Applied Research in Mechanical Engineering (JCARME)
2228-7922
2251-6549
2013-09-11
3
1
75
83
10.22061/jcarme.2013.61
61
Derivation of turbulent energy in a rotating system
S. F. Ahmed
1
Prime University, Mirpur-1, Dhaka-1216, Bangladesh
Energy equation for turbulent flow in a rotating system was derived in terms of second order correlation tensors, where the correlation tensors were functions of space coordinates, distance between two points and time. To reveal the relationship of turbulent energy between two points, one point was taken as origin of the coordinate system. Due to rotation, the Coriolis force played an important role in the rotating system of turbulent flow. The correlation between pressure fluctuations and velocity fluctuations at the two points of flow field was applied to the turbulent energy equation, in which the Coriolis force and centrifugal force acted on the fluid.
http://jcarme.sru.ac.ir/article_61_c7c4c1f5f278c46b3e57b15c80f285a6.pdf
Energy equation
Turbulent flow
Rotating system
Two-point correlation
Correlation tensor