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ARPN Journal of Engineering and Applied
Sciences
June 2012 | Vol. 7 No. 6 |
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Title: |
Stress
analysis of standard truck chassis during ramping on block using
finite element method |
Author (s): |
Haval Kamal
Asker, Thaker Salih Dawood and Arkan Fawzi Said |
Abstract: |
The frame of the standard
dump truck supports all types of complicated loads coming from
the road and freight being loaded. So, the intensity and the
strength of the frame play a big role in the truck's design. A
frame of 6 wheels, standard dump truck has been studied and
analyzed using ANSYS package software. The static intensity of
the frame has been analyzed when exposed to pure bending and
torsion stress, within two cases. First case is when the rear
wheels zigzag gets over block (only one side of the chassis
steps the block), and the second case is when both wheels gets
over the block. Finite element model of a stress analysis of
the vehicle chassis has been built using three dimension hyper
elastic elements for the modeling. The results show important
differences between the two case studies, especially in the
torsion and deformations results obtained from the chassis
model. Also, vibration modes have been analyzed during the
loading conditions. The more damping ratio used, the more
stabilizing of the stresses with respect to time. |
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Title: |
Scour hole characteristics around a
vertical pier under clear water scour conditions |
Author (s): |
Padmini Khwairakpam, Soumendu Sinha Ray,
Subhasish Das, Rajib Das and Asis
Mazumdar |
Abstract: |
A series of clear water scour experiments have been conducted
in a tilting flume with a circular pier under different
conditions of densimetric Froude number and inflow depths.
Tests used a single pier of 50 mm diameter embedded in a sand
bed of mean particle size d50=0.365 mm. It
was observed that the entire scour geometry (scour depth,
length, width, area and volume) depended on the densimetric
Froude number (FD50) and inflow
depth (h). On the basis of the obtained results,
empirical equations are proposed for scour depth, scour
length, scour width, scour area and scour volume. Scour hole
parameters calculated from the proposed equations have been
compared with those obtained from experimental results and are
found to be very close to each other. |
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Title: |
Axiomatic development of human
psychophysiological stress indices using thermodynamics |
Author (s): |
Satish C.
Boregowda, Rodney Handy, Olafur S.
Palsson and Carol A. Boregowda |
Abstract: |
The present study involves development of an original
quantitative methodology based on the principles of
thermodynamics to define and measure human stress responses.
The methodology combines five physiological measures (blood
pressure, heart rate, finger skin temperature, facial
electromyogram, and skin conductance level) to develop an
Objective Stress Index (OSI). The study included
forty-nine medical residents (28 males and 21 females). The
physiological measures were taken under three conditions
during the psycho physiological test profile. The
Stress-Related Physical Symptoms Inventory (SPSI)
questionnaire was administered during the course of the psycho
physiological procedure. The Subjective Stress Index (SSI),
a ratio of the severity of stress symptoms to the number of
stress symptoms, was derived from the SPSI questionnaire.
Without making any assumption about the distribution of the
data, a nonparametric Mann-Whitney test was performed on the
OSI and SSI data. The OSI results indicate that there was a
significant difference in male and female stress responses. It
is concluded that OSI in combination with the SSI will provide
a quantitative framework for biomedical engineering
researchers and practitioners to develop standards for
measurement and evaluation of human stress responses. |
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Title: |
Optimum design of switched reluctance
machine using adaptive particle swarm optimization |
Author (s): |
Balaji M.
and Kamaraj V. |
Abstract: |
This paper presents swarm intelligence based Adaptive Particle
Swarm Optimization (APSO) technique to determine optimum
design of Switched Reluctance Machine (SRM). In APSO
technique, the inertia weight factor is made adaptive on the
basis of objective functions of the current and best solutions
to avoid premature convergence. The
SRM design is treated as nonlinear multivariable constrained
optimization problem. The objective functions for obtaining
desired design are maximizing torque density, minimizing
torque ripple and minimizing copper loss with stator and rotor
pole arc as design variables. The potential of the
proposed approach is tested on 8/6
four-phase, 5 HP, 1500 rpm SRM and the results are compared
with those obtained from Genetic Algorithm (GA) and
classical PSO technique. The results
demonstrate that the proposed method is superior in terms of
solution quality, accuracy, robustness and computational
efficiency. |
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Title: |
Dual converter controlled single phase
matrix converter fed DC drive |
Author (s): |
D. Venkatasubramanian,
S. P. Natarajan, B. Baskaran and
S. Suganya |
Abstract: |
This paper presents an application of
Single Phase Matrix Converter (SPMC) as a dual converter.
Pulse Width Modulation (PWM) techniques are used to calculate
the switch duty ratio to synthesize the output. Chosen PWM
technique incorporating wave shaping is also used to ensure
continuous supply current. Basic loads represented by R, R-L,
motor loads are used in this investigation. The performances
of chosen DC drive with SPMC based dual converter and SCR
based dual converter are compared and analyzed. Selective
simulation results are presented to verify the strategies
developed. It is found that SPMC is a versatile topology. |
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Title: |
Distribution transformer with amorphous-CRGO core:
An effort to
reduce the cost of amorphous core distribution transformer |
Author (s): |
Man Mohan
and Puneet Kumar Singh
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Abstract: |
In distribution transformer design, main stress is to reduce
core losses. To reduce core losses in distribution transformer
cold-rolled grain oriented (CRGO) steel is preferred by
manufacturers. Amorphous material has very less core losses
compared to CRGO steel, therefore it is being seen as a good
substitute of CRGO steel. Now-a-days some manufacturers are
using amorphous material in miniature and medium size
transformers in place of CRGO steel. The cost of amorphous
core transformer is higher than the cost of CRGO core
transformer. Here an effort is being made to reduce the cost
of amorphous core distribution transformer by using a
‘CRGO-Amorphous’ core in place of amorphous core. A comparison
is being presented here among ‘CRGO core distribution
transformer (CCDT)’, ‘amorphous core distribution transformer
(AMDT)’ and ‘Amorphous-CRGO core distribution transformer (AMCCDT)’,
in terms of cost and efficiency. |
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Title: |
Chlorite group minerals from the
amphibolite facies metamorphic rocks of Krivaja-Konjuh Ultramafic
massif
in Bosnia and Herzegovina |
Author (s): |
M.
Operta, S.
Hyseni and S.
Salihović |
Abstract: |
In amphibolite rocks, in the southern edge of Krivaja-Konjuh
ultramafic massif, six samples are separated (from localities
Stupčić I, Stupčić II, Pobilje, Donja Vijaka and Selište) in
which occurrences of minerals of chlorite group are confirmed
using optical tests. Mineral composition of samples of rocks
is checked using x-ray analyses on the instrument of brand
Philips with CuKa
radiation with graphite monochromator. Chemical composition of
mineral-chlorite in rocks was determined using electronic
microsonde (ARL-SEMQ). Analyses of chlorite were calculated in
accordance with recommendations of HYPER-FORM (S. Borg, A.
Moggesie and E-Bjerg, 1991). Calculation of formulas of
chlorite was done on the basis of 28 O and 36 (O, OH). In
Bosnia and Herzegovina, minerals of chlorite group are very
frequent and developed compounds in igneous, sedimentary and
metamorphic rocks. Even though they are mentioned in numerous
petrography and mineralogy papers, most of the authors of
petrography papers describe chlorites as members of the
mineral groups, and articles where more detailed selection or
description of certain types of chlorite are given are more
rare.
Quantity of chlorite in amphibolite rocks in the area of
Vijaka is variable. Chlorite in amphibolite rocks in the are
of Vijaka occurs:
In the shape of bands at contacts of amphibolite rocks with
ultramafic rocks. In the crust of decaying of amphibolite
rocks. As inclusions in corundum, garnets, amphiboles,
pyroxene, plagioclase, and in u celyphitic rim of garnets as a
product of retrograde metamorphism in the condition of
hydrothermal metamorphosis. |
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Title: |
Frequency offset estimation in coherent
OFDM systems using different fading channels |
Author (s): |
Haritha T.,
S. SriGowri and D. Elizabeth Rani |
Abstract: |
The well known problem in an orthogonal frequency division
multiplexing (OFDM) system
is its sensitivity to frequency offset. Most of the coherent
OFDM systems transmit pilot symbols on some of the
subcarriers to estimate channel attenuation and also add a
cyclic prefix (CP) to avoid intercarrier interference and intersymbol interference. An
estimation algorithm based on the redundancy of both
cyclic prefix and pilot subcarriers is proposed for the
correction of frequency offset. If the frame timing is
synchronised in advance, by
considering the two kinds of redundancy simultaneously, the
performance of the proposed hybrid algorithm achieves
significant improvement under low
SNR and short CP. As to
high SNR and long CP, the performance of the hybrid algorithm
is almost identical to that of CP-based algorithm. Some
comparative simulations are given to illustrate the advantages
of the proposed hybrid estimation scheme. |
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Title: |
Evaluation of dynamic parameters of
adhesively bonded steel and aluminum plates |
Author (s): |
Sourabha S. Havaldar, Ramesh S. Sharma,
V. P.
Raghupathy
and Moortheesha Adiga |
Abstract: |
Weight reduction remains one of the key factors for various
industries. Inevitably this will result in multi-material
designs where the most appropriate material is selected for
each part. A key enabler for such a multimaterial design is
joining two materials with optimized weight which is balanced
with the need to keep manufacturing costs down. Further, it is
well known that these parts are subjected to dynamic load
while in service conditions, and in order to evaluate dynamic
parameters for design purpose an adhesively bonded dissimilar
joint between Aluminium and Mild steel plates has been
investigated experimentally through traditional “strike
method” of modal testing. FE simulation is also carried out
and are compared with experimental results and found to be in
good agreement. |
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Title: |
Application of intelligent control
techniques for global maximum power point tracking of solar
photovoltaic system |
Author (s): |
Ramaprabha
R. and Mathur B. L. |
Abstract: |
In this paper, a fuzzy logic
based feedforward voltage method of global maximum power point
(GMPP) tracking scheme is developed for the boost converter
supplied Solar Photovoltaic (SPV) system. With the developed
realistic model of SPV array and boost converter the proposed
controller has been simulated. The reference voltage is
obtained from Artificial Neural Network (ANN). The ANN was
trained for optimum values computed from Particle Swarm
Optimization (PSO) technique. Fuzzy Logic Controller (FLC) is
used to find the error in voltage and the output from FLC is
fed to Pulse Width Modulator (PWM) to control the boost
converter. Comparison studies have been made for Proportional
plus Integral (PI) and FLC. From the simulation results, it is
observed that the feedforward control strategy with fuzzy
controller reduces error and it is a promising one with
reference to GMPP tracking. Furthermore, it does not require
any tuning of the parameters, unlike conventional PI
controller, wherein the controller gain parameters needs to be
changed when solar insolation changes. |
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Title: |
Compatibility of 3-D turning diffusers by
means of varying area ratios and outlet-inlet configurations |
Author (s): |
Normayati
Nordin, Vijay R. Raghavan and Safiah
Othman |
Abstract: |
Combined
turning and diffusing is often associated with detrimental
flow phenomena that contribute to losses induced by the very
nature of its geometry.
This paper aims to investigate the compatibility of using 3-D
turning diffusers in improving pressure recovery and flow
uniformity by means of varying area ratios (AR) and
outlet-inlet configurations (W2/W1, X2/X1).
There were three cases considered; (i) Case A (reference)
- 2-D turning diffuser (AR=2.0, W2/W1=2.0,
X2/X1=1.0), (ii) Case B- 3-D
turning diffuser (AR=2.0, W2/W1=1.5, X2/X1=1.3)
and (iii) Case C- 3-D turning diffuser (AR=4.0 W2/W1=1.5
and X2/X1=2.7). Inflow Reynolds Number
(Re) approximately of 20 was applied. The experimental rig was
set up with the diffuser models fabricated using acrylic.
Particle Image Velocimetry (PIV) was used to acquire the
velocity profile and visualize the flow structure in the
diffusers. Digital manometer with resolution of 0.1Pa provided
pressure values. Results show pressure recovery (Cp)
of respectively 0.3, 0.1 and 0.5 gained for Case A, B
and C. In terms of flow uniformity, standard deviations
(su)
of 2.04E-03, 3.14E-03 and 2.57E-03 were recorded respectively.
There was a reduction in terms of recovery and uniformity when
a 3D turning diffuser with an AR=2.0 was introduced. Whereas,
the compatibility of 3-D turning diffuser with an AR=4.0 seems
more promising. The results obtained in this study will be
used to validate the CFD codes. The intensive CFD simulation
by means of varying other geometry configurations in the event
of different inflow Reynolds number will be carried out in
future. |
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Title: |
Development
of the construction productivity estimation model using
artificial neural network
for finishing
works for floors with marble |
Author (s): |
Faiq Mohammed
Sarhan AL-Zwainy, Hatem A. Rasheed and Huda Farhan Ibraheem |
Abstract: |
Estimation of the productivity
is an important task in the management of construction
projects. The quality of construction management depends on
accurate estimation of the construction productivity. In this
paper, Multi-layer perceptron trainings using the
back-propagation algorithm neural network is formulated and
presented for estimation of the productivity of construction
projects. Data used in the study are for
residential, commercial and educational projects from
different part from Iraq. These are used in training the model
and evaluating its performance. Ten influencing
factors are utilized for productivity forecasting by ANN
model, they include age,
experience, number of the
assist labor, height of the
floor, size of the marbles
tiles, Security Conditions, health Status for the work team,
weather conditions, site condition, and availability of
construction materials. One model was built for the
prediction the productivity of marble finishing works for
floors. It was found that ANNs have the ability to predict the
productivity for finishing works with a very good degree of
accuracy of the coefficient of correlation (R) was 89.55%, and
average accuracy percentage of 90.9%. |
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Title: |
Processing of waste polyethylene into polymer-ceramic composite
through lipid assisted melt compounding |
Author (s): |
Yaw Delali Bensah, Benjamin
Agyei-Tuffour, Lucas N. W. Damoah and Johnson K. Efavi |
Abstract: |
In this work, a modified approach to melt compounding has been
successfully developed to study the dispersion of kaolin
particles in polyethylene and properties of
polyethylene-kaolin clay composites. The process involved the
use of melt compounding technique with vegetable lipid acting
as a melting medium with the capability to enhance miscibility
of the polyethylene with the kaolin which is necessary for
strength improvement of the polyethylene-kaolin composite.
Eight different compositional batches were formulated and cast
at 300 oC. In all the thermal and mechanical
properties as well the microstructure of the composites were
studied. Comparisons of the composites with pristine
polyethylene-lipid have shown an improved glass transition
temperature (Tg) and the thermal decomposition
temperatures as a result of changes in the chemical structure.
Proportional kaolin additions did not change the
crystallization temperature (Tc) of the blends as
compared to the pristine polyethylene-lipid blend.
Incorporation of 60 % kaolin by weight in the
polyethylene-lipid matrix significantly improved the
mechanical properties of the composites to its peak and an
increased compressive strength of 2.0 to 8.7 MPa has been
measured. Scanning electron microscopic (SEM) analyses shows
the formation of a web-like entanglement caused by the
dispersion of the kaolin particles in the matrix. |
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Title: |
A case of similarity solutions for unsteady
laminar boundary layer flow in curvilinear surface |
Author (s): |
M.
Yeakub Ali and M. G. Hafez |
Abstract: |
In this paper, a study is made of the unsteady
laminar natural convection boundary layer equations on a
vertical curvilinear surface to establish necessary and
sufficient conditions under which the similarity solutions are
possible. The free parameter method is used to obtain
similarity solutions. One of the cases of possible similarity
solutions are discussed analytically and numerically. |
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Title: |
An
inexpensive shielded acoustic probe for pressure measurements
near a radiating ultrasonic transducer |
Author (s): |
Peter W.
Higgins and Corinne S. Lengsfeld |
Abstract: |
Conventional field measuring
sensors such as hydrophones, thermistors, and thermocouples
are susceptible to contamination by the voltage signal
emanating from the ultrasonic field generator when there is
any contact with the measurement medium. Such EMR, entering
the zone of measurement can be orders of magnitude greater
than the voltage resulting from the measurement of the field
itself. This work describes the design and characterization of
a piezoelectric (PZT) planar disk encased within a separately
grounded Faraday cage to act as a pressure field sensor. It is
demonstrated that the separate grounding of this cage
effectively eliminates the EMR contamination. Further, the
work describes a calibration procedure incorporating a force
beam to translate strain from a static load, and then from a
dynamic load at the frequency of interest. Experimental
measurements with this probe design show a near 80 %
correlation to a theoretically calculated wave form using ray
tracing to simulate the pressure field in the test cell. |
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Title: |
Finite element analysis of thermal
characteristics of annular fins with different profiles |
Author (s): |
M. Sudheer,
G. Vignesh Shanbhag, Prashanth Kumar and
Shashiraj Somayaji |
Abstract: |
The selection of a particular fin configuration in any heat
transfer application depends on the space, weight,
manufacturing technique and cost considerations as well as the
thermal characteristics it exhibits.
Radial or annular fins are one of the most popular
choices for enhancing the heat transfer rate from the primary
surface of cylindrical shape.
Different profiles have profound influence on the thermal
characteristics of annular fins. In the present study, a
detailed work has been carried out to develop a finite element
methodology to estimate the temperature distribution for
steady-state heat transfer and thermal stresses induced by
temperature difference in a silicon carbide (SiC) ceramic
finned-tube of the heat transfer equipment.
Finite element method (FEM) was used to compute the
temperature and the stress fields. An extensive
study was carried out using ANSYS, a powerful platform for
finite element analysis. Results obtained were presented in a
series of temperature and thermal stress distribution curves
for annular fins with rectangular, trapezoidal and triangular
profiles for a wide range of radius ratios. It was found that
the radius ratio and fin profiles are the significant
parameters affecting the temperature and thermal stress
distribution in annular fins. |
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Title: |
Effect of chemical treatments on mechanical
properties of jute fiber hybrid composite laminates |
Author (s): |
B. Sutharson,
M. Rajendran, S. R. Devadasan and
B. Selvam |
Abstract: |
A study has been carried out to investigate the tensile
properties of alkali
Treated woven jute natural fiber and woven glass fiber
reinforced hybrid composites bolted joint (TCBJ)
and Untreated Hybrid
Composite bolted joint (UTCBJ).
Effect of stacking sequence
and fiber treatment on tensile strength,
hardness
and impact strength of alkali treated woven jute natural fiber
and woven glass fiber reinforced
hybrid composites and
Untreated Hybrid Composite has been investigated
experimentally.
It has been observed that the tensile properties increase with
respect to jute fiber content. The results indicated that the
properties of jute composites can be considerably improved by
incorporation of glass fibre as extreme glass plies. The layer
sequence has greater effect on
hardness
and Impact Strength. |
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Title: |
Control design and simulation of
distributed power-flow controller (DPFC) |
Author (s): |
P. Ramesh
and M. Damodara Reddy |
Abstract: |
The present paper describes the steady-state response and
control of power in Transmission line equipped with FACTS
devices. Detailed simulations are carried out on two-machine
systems to illustrate the control features of these devices
and their influence to increase power transfer capability and
improve system Reliability. The DPFC is derived from the
unified power-flow controller (UPFC) and DPFC has the same
control capability as the UPFC. The DPFC can be considered as
a UPFC with an eliminated common dc link. The active power
exchange between the shunt and series converters, which is
through the common dc link in the UPFC, is now through the
transmission lines at the third-harmonic frequency. The
interaction between the DPFC, the network and the machines are
analyzed. |
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Title: |
Geochemistry and economic potential of
marble from Ikpeshi, south-west, Nigeria |
Author (s): |
Romanus
Obasi and Fredrick Isife |
Abstract: |
Nigeria is endowed with varieties of valuable solid minerals
and rocks. These minerals/rocks are capable of boosting the
economic potentials of the country if fully exploited. Marble
is one of such rocks that occur prominently in Ikpeshi area of
Edo State, South-west, Nigeria Forty five (45) marble samples
were subjected to geochemical, petrographic and physical
analyses. Geochemical data show that the marble has variable
geochemical characteristics; low dolomite CaMg (C03)2
(1.35-7.44%) and high calcite CaCO3 (82.78-95.61%)
for those from other quarries and moderate dolomite
(41.38-41.42%) and moderate calcite (61.03-61.58%) for those
from the Golden Girl quarry. Physical tests indicate high
tensile strength (17.342-31.550MPa), compressive strength
(259.515-3892.73MPa) and shear strength (44.70-68.51MPa)
respectively. Petrographical studies reveal that the marble
contains calcite, dolomite, quartz, opaque mineral, actinolite,
lead, feldspar and chlorite. Based on these characteristics,
the marble from Ikpeshi is suitable as raw materials for
manufacture of lime, drugs, toothpaste, paper and paint. It is
also important in the production of livestock feed, electrical
insulators, flooring tiles and terrazzo chips. The marble is
unsuitable for cement production. |
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Title: |
Diagnosis of faults using IMM estimator |
Author (s): |
M.
Raghappriya, S. Kanthalakshmi and V.
Manikandan |
Abstract: |
An approach to detection and diagnosis of multiple faults is
proposed. It is based on Interacting Multiple Model (IMM)
algorithm. The proposed approach provides means of detection,
diagnosis of faults and state estimation. It is able to detect
and diagnose the fault more quickly and reliably than other
methods. In this paper the threshold values of various types
of faults is also proposed. This is illustrated using an
Aircraft example which has multiple failures-sensor, actuator
and other component failures. |
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