Print ISSN: 1681-6900

Online ISSN: 2412-0758

Issue 3,

Issue 3


Transient Thermal Stress Prediction Due To Flow of Coolant Through Hot Pipe

Anes F. Saad; Jalal M. Jalil

Engineering and Technology Journal, 2011, Volume 29, Issue 3, Pages 423-433

Transient thermal stresses in pipe wall due to coolant turbulent flow
through pipe are investigated in this study with transient isothermal hot boundary
in the external pipe radius. Three Different values of Reynolds are tested (3000,
5000 and 8000). Finite volume method was used to calculate the velocities and
temperatures fields in the working fluid (air). Thermal resistance method was used
to calculate the transient temperature distribution in the pipe wall and then the
transient thermal stresses were calculated. Minimum thermal stress was located
nearly in the mid plane of the pipe.

Three-Dimensional Flow Model for The Downstream of Kuffa Barrage

Majid H. Hobi; Saleh I. Khassaf; Muhannad J. M. Al-Kizwini

Engineering and Technology Journal, 2011, Volume 29, Issue 3, Pages 434-441

The three-dimensional numerical computational fluid dynamics “CFD”
computer program "SSIIM" was used to predict the flow field downstream the
Kuffa Barrage. It solved the Reynolds-Averaged Navier–Stokes equations in three
dimensions to compute the water flow and used the finite-volume method as the
discretization scheme. The model was based on a three dimensional, nonorthogonal,
structured grid with a non-staggered variable placement. The
comparison between filed measurements and numerical results were considered to
make the correct decision in this model. The results showed that the maximum
velocities were inclined from the river center. The determination coefficients for
distribution of velocities ranged from 0.94 to 0.96.

Applicable Studies of the Slow Electrons Motion in Air with Application in the Ionosphere

S. S. Dawood; F. G. Hamudy; M. I. Ismaeel; I. G. Faiadh

Engineering and Technology Journal, 2011, Volume 29, Issue 3, Pages 442-461

In this study, the motions of slow electrons in air and nitrogen with it's
mixtures are studies by details. We solved numerically Boltzmann transport
equation to calculate the parameters E, Vd
and D/m have been possible to deduce
expression empirical formula from which may be derived the drift velocity,
collisional frequencies, electronic temperature and mean energy loss per collision.
These results applied to the ionosphere allow electronic collisional frequencies to
be ready found in the ionosphere below 94 km, from the pressure of the air. The
collision cross-sections of the molecules of air and nitrogen when the electronics
temperature is less than about 2600°K.
The addition results are presented for electrons drifting through air in a steady
state of motion under the action of the electric field, such as, KT, U, Q, Q0, ω,
ω/P,h, hKT , and W/D for both Maxwell and Druyvesteyn distribution laws. This
parameters are graphically as a functions for their variables.
The results appeared excellent agreements with the experiments and
theoretical data.

Edge Detection Based on Standard Deviation Value and Back Propagation Algorithm of Artificial Neural Network

Ammar Sabr Majed; Mohammed Hussien Miry; Ali Hussien Miry

Engineering and Technology Journal, 2011, Volume 29, Issue 3, Pages 462-469

This paper presents a proposed neural network based edge detection
algorithm. we have used artificial neural network system to decide about whether
each pixel is edge or not. First standard deviation values are computed for mask
(3*3), Then after training a neural network system to recognize structural patterns
(these pattern represents edges), it decides on each pixel if its edge or not. Finally
we have test the proposed method on different images. Experimental results show
the ability and high performance of proposed algorithm.

A Study Of Some Hydrological Aspects For Spillway Design of A Small Dam In The North of Iraq

Sahar A. Mohammad

Engineering and Technology Journal, 2011, Volume 29, Issue 3, Pages 470-476

This research is to evaluation and analyzing the main aspects of spillway design
for Chaq-Chaq dam in north of Iraq in Suleimaniya governorate, with help of the
hydraulic, hydrologic and climate data collecting. Four different distribution models
are used in order to conduct the analysis required to find the different return periods
of flood, based on the expected daily rainfall depth, also the result was compared
with the study of Sogreah consulting company .Analysis of data shows that the
length of the spillway of Chaq-Chaq dam should be increased by about 206% to
accommodate the maximum flood discharge according to Extreme Value type I
distribution with return period of 1000 year.

Experimental Investigations Heat Transfer and Pressure Drop Characteristics of Flow Through Circular Tube Fitted With Drilled Cut-Conical Rings

Ameer A. Jadoaa

Engineering and Technology Journal, 2011, Volume 29, Issue 3, Pages 477-487

The heat transfer rate and pressure drop characteristics of turbulent flow of air
through uniformly heated circular tube fitted with drilled cut conical rings with
three space ratios (X=5.4, 6.4, and 8.4) have been studied experimentally. The flow
characteristics are governed by space ratio (the ratio of the distance between drilled
conical ring and the inner diameter of tube), Reynolds number, and drilled conical
ring diameter to inner diameter of tube. The goal of the present work is to
investigate the effect of drilling of the cut conical ring turbulators (with constant
ring to tube diameter ratio) and space ratio on heat transfer, friction factor, and
enhancement efficiency under ranging of Reynolds number from 5000 to 23500.In
addition, correlation for Nusselt number, friction factor and performance
evaluation criteria to assess the real benefits in using the drilled-conical ring
turbulator of the enhanced tube are determined. The results show that the process
of drilling of the conical ring inside tube gives high rates of heat transfer more than
that in the conical ring without drilling.

Poisson's Ratio as a Function of Time in Composite Material of Viscoelastic Behavior by Depending on Creep Test

Azhar Sabah Ameed

Engineering and Technology Journal, 2011, Volume 29, Issue 3, Pages 488-498

In viscoelastic behavior of composite material, such as those made of thermo-set
polyester and one layer random fiber glass, the Poisson’s ratio is described in new
function of time and stress. The relaxation stress is obtained experimentally to describe
the non-linear viscoelastic behavior in composite material. The results show that,
Poisson’s ratio increases with an approximate rate of 16% as a result of the increasing
stress from 6.877 MPa to 8.239 MPa and decreases with increasing the time at constant
temperature 30 Co.
The investigation demonstrated that such time dependence is not a necessary
consequence of the theory of viscoelasticity to describe viscoelasticity behavior.

Design and Implementation Web Site for UOT Using Mobile Devices

Zahraa Abid AL-Huseen; Aimen Kazim; Mohammad Natiq; Alaa Kadhim

Engineering and Technology Journal, 2011, Volume 29, Issue 3, Pages 499-512

A mobile phone allows its user to make and receive telephone calls to and
from the public telephone network which includes other mobiles and fixed-line phones
across the world. In addition to being a telephone modern mobile phones also support
many additional services, and accessories. such as SMS (or text) messages, e-mail,
Web access, gaming, Bluetooth and infrared short range wireless communication,
camera.
The Mobile Web refers to the use of Internet-connected applications, or browser-based
access to the Internet from a mobile device - such as a Smartphone or tablet PC -
connected to a wireless network. In this paper, we design and build an web application
on the mobile devices and access to the web services to display the university of
technology website.

Effective Web Page Crawler

a Tahseen Ali; Isra; Hilal Hadi Saleh

Engineering and Technology Journal, 2011, Volume 29, Issue 3, Pages 513-530

The World Wide Web (WWW) has grown from a few thousand pages in
1993 to more than eight billion pages at present. Due to this explosion in size,
web search engines are becoming increasingly important as the primary means
of locating relevant information.
This research aims to build a crawler that crawls the most important web
pages, a crawling system has been built which consists of three main
techniques. The first is Best-First Technique which is used to select the most
important page. The second is Distributed Crawling Technique which based on
UbiCrawler. It is used to distribute the URLs of the selected web pages to
several machines. And the third is Duplicated Pages Detecting Technique by
using a proposed document fingerprint algorithm.

Structural and Optical Properties of Lead Iodide Thin Films Prepared By Vacuum Evaporation Method

Khalid M. Thajeel; Modaffer A.Mohammad; Ali M .Mousa; Shatha Sh. Jamil

Engineering and Technology Journal, 2011, Volume 29, Issue 3, Pages 531-543

Structural and optical properties were studied as a function of films thickness for
thermally evaporation PbI2 films. X-ray diffraction analysis confirmed that PbI2
films are polycrystalline having hexagonal structure. The optical absorption data
indicate an allowed direct transmission with optical energy gap varies continuously
from ( 2.15eV to 2.33eV) . The energy gap shows thickness dependence, which
can be explained qualitatively by a thickness dependence of grain size through the
decrease of the grain boundary barrier height with grain size. The low fluctuation
in energy gap indicates that the grain size is quite small, which is finding in
agreement with AFM results.

On Left s -Centralizers Of Jordan Ideals And Generalized Jordan Left (s ,t ) -Derivations Of Prime Rings

Abdulrahman H. Majeed; Anwar Khaleel Faraj

Engineering and Technology Journal, 2011, Volume 29, Issue 3, Pages 544-553

In this paper we generalize the result of S. Ali and C. Heatinger on left s -
centralizer of semiprime ring to Jordan ideal, we proved that if R is a 2-torsion free
prime ring, U is a Jordan ideal of R and G is an additive mapping from R into
itself satisfying the conditionG(ur + ru) = G(u)s (r) + G(r)s (u) , for all
uÎU, r ÎR . Then G(ur) = G(u)s (r) , for all uÎU, r ÎR . Also, we extend the
result of S. M. A. Zaidi, M. Ashraf and S. Ali on left (s ,s )-derivation of prime ring
to Jordan ideal by introducing the concept of generalized Jordan left (s ,t )-
derivation.

Detection of Water-Table by Using Ground Penetration Radar (GPR)

Ahmed Fouad Nashait; Mundher Ali Seger

Engineering and Technology Journal, 2011, Volume 29, Issue 3, Pages 554-566

Ground penetrating radar, GPR, is a high resolution geophysical method,
which is based on the propagation of high frequency electromagnetic waves. The
GPR method images structures in the ground that are related to changes in
dielectric properties. In sediments, water content primarily causes the changes in
dielectric properties. Therefore GPR can be used to estimate underground watertable.
In this study a GPR system has been used successfully to produce a
continuous profile of the water table on the (Said Abdullah bin Al-Hassan Shrine)
as a study area, which is located in Al-Yousifyah region to the south of Baghdad.
Geotechnical field test to underground water determination by the drilling method
commonly used to comparing the results between geotechnical field test and GPR
test. Thus, GPR has proven to be an effective detection method for underground
water level, and can serve as reference for future applications.

Residual Stress effect on Fatigue Behavior of 2024- Aluminum alloy

Riyadh A. Al-Taie; Farag Mahel Mohammed; Ahmed N.Al-khazraji

Engineering and Technology Journal, 2011, Volume 29, Issue 3, Pages 567-578

In the present work the effect of residual stress on the fatigue behavior of
2024 Aluminum alloy was studied experimentally and numerically using
finite element method with aid of ANSYS-11 software. All the test
specimens treated by annealing before any process to remove the internal
stresses due to cold work. Residual stresses were imparted to the fatigue tests
specimens by heat treatment, pre-strain and welding. X-Ray diffraction was
used to measure the residual stress.
The heat treatment; done on the test specimens with different temperature of
(420, 450, 480, and 510) oC. After heat treatment; alloy mechanical properties
were improved. For the heat treated specimens as the temperature increased
the compressive residual stress increased to (27.06, 41.43, 72.8 and 85.6)
MPa. That leads to increase the endurance fatigue limit by (32.93%, 40.48%,
50.68% and 61.03%) respectively than other alloy as received. While in pre
strain groups; the test specimens loaded to (265, 290, 315 and 340) MPa by a
tension test machine. As the applied load series were increased the
compressive residual stress increased to (16.51, 25.62, 51.54 and 62.44) MPa
which improve the endurance fatigue limit by (7.68%, 16.19%, 24.98%, and
46.45%), respectively. An electrical arc and metal inert gas were used in
welding series to weld the test specimens, that present a tensile residual stress
of (76.93 and 72.66) MPa, which reduces the endurance fatigue limit by
(23.45% and 16.08%), respectively. The numerical results present fatigue
behavior, deflection and stress at any load, and show a reasonable agreement
results with an experimental one.

Smith Predictor with Simple Control Scheme for Higher Order Systems

Qussay S.Tawfeeq; Nasir.A.Al-awad; Ekhlas H. Karam

Engineering and Technology Journal, 2011, Volume 29, Issue 3, Pages 579-594

A simple control scheme with smith predictor connection is proposed in
this paper for time delay higher order systems. The control scheme is
simply integral (I) controller with Proportional Derivative(PD)-Sliding
mode controller(SMC). The initial values for the P,I, and D parameters are
taken from the reduced model of the higher order system. Additional
feedback sliding mode control (FSMC) is also used to reduce the effect of
uncertainty in the prediction time delay values. A number of examples are
tested and compared with other control methods like robust PID controller
with smith predictor and Direct synthesis method with smith predictor to
illustrate the efficient performance for the proposed control scheme.

Removal of Heavy Metals Using Chemicals Precipitation

Balasim A. AbiD; Mahmood M. BrbootI; Najah M. Al-ShuwaikI

Engineering and Technology Journal, 2011, Volume 29, Issue 3, Pages 595-612

The single component and multi-component hydroxide precipitation and
adsorption were studied for different heavy metals namely Iron (III), Chromium
(III), Copper (II), Lead (II), Nickel (II), and Cadmium (II) from aqueous solutions.
By using the jar tester Magnesia (MgO) was used as a precipitator at different
doses and compared with other chemicals like lime (CaO) and caustic soda
(NaOH). The treatment involves the addition of either magnesia or lime-water
suspensions (combined with cationic polyelectrolyte, CPE) in various doses, 1.0 –
5.0 g/l for the metal samples to study the effect of varying doses on the treatment
efficiency. The results show that the percent removal of metal ions increases to
about 99 % with increasing the MgO dose to some limits. The optimum values of
MgO doses were found to be 1.5-3.0 g/l. The pH value ranges are 9.5 to 10 with
MgO precipitant and pH of 11.5 to 12 with CaO precipitant. In the jar experiment
the rotation speed, N, 180-200 rpm, (G of 460-480 s-1) of mixing for two minutes
was the most favorable speed of rapid mixing and the slow mixing speed of 15-30
rpm, G of (14-35 s-1), for twenty minutes gave the best results.At the best operating
conditions of the pilot plant, the removal efficiency of metal ions was more than
97% at doses of MgO (1.0-4.0 g/l).

Solutions of Dynamic Fractional Order Differential Algebraic Equations System

Alauldin Noori Ahmed

Engineering and Technology Journal, 2011, Volume 29, Issue 3, Pages 613-624

In this paper, we are presented the existence and uniqueness theorem, and two
proposed methods, based on the theory of Gunwald-Letnikov fractional order
derivative. In the first method, the variational approach is implemented, while in
the second method, the fractional difference approach is implemented. Dynamic
test example is presented to each proposed method, to demonstrate their
computational algorithm.

Improving a Model for Speed / Density Relationship on Arterial Roads in Baghdad City

Abeer Khudher Jameel

Engineering and Technology Journal, 2011, Volume 29, Issue 3, Pages 625-638

This paper was undertaken to investigate the relationships between speed
and density on urban arterial roads of Baghdad City. This research work was based
on the traffic survey data (PC volume and average speed) collected in Palestine
Street in 3 sections at two directions through 12 hours within 3 weekdays. The
density is computed using fundamental formula of traffic flow. Eight theoretical
Speed-Density models (5 are single Regime Models and 3 are Multi-Regime
models) are validated by the field data by two statistical test methods (CHISQ test
and Paired T-test). The results show that no one of the theoretical models is good
in fit with the real data. Then a Multi-Regime Model is improved under two ranges
of density (<70 and >70) at south approach and (<60 and >60) at north appraoch .
This model is tested using regression analysis, CHISQ test, and Paired T-test. This
analysis shows that the model has good fit with the field data.

Some Factors Effecting on the Dielectric Strength for (PVC- Kaolin) Composites

Engineering and Technology Journal, 2011, Volume 29, Issue 3, Pages 103-116

This research includes the effect of kaolin additions to the polymer matrix (PVC)
and study some factors affecting to dielectric strength.
The kaolin powder was added as percentage by weight (1,2,3 and 4%) to PVC,
and the specimens formed by hot pressing method, with different thickness (0.8-2
mm). Some of the results was showed decrease in the electrical strength with kaolin
additives, especially for large thickness due to presence of lattice water, which has
high dielectric constant but in the same time has high dielectric loss factor, where the
electrical strength decrease when dielectric loss factor increases. Thus the influence of
leakage currents is evident in the large thickness as a result of the electro-thermal
effects.
Electrical strength was decreased when the time rate of raising voltage increases.
The effect of the cycles number of breakdown for composite specimens was studded.
Also the dielectric strength decreased with temperature increases.
Optical microscopy images for breakdown region was shown the
carbonization in the breakdown points as a result of crashing polymers chains.
Also, micro cracks occurring for specimens that has large amount of kaolin and
this cracks extend directly from the breakdown region.

Study of Spectroscopy and Thermodynamic Properties for Germanium Tetrafluoride GeF4 Molecular and Study of Potential Energy Curve for Bond (Ge-F)

Engineering and Technology Journal, 2011, Volume 29, Issue 3, Pages 117-124

In This research Complete study Spectroscopic and Thermodynamic
properties for molecule GeF4 . This included calculation of potential energy
curve . from this curve total energy of molecule at equilibrium distance
calculated , for bond (Ge - F) the degenerated of (Ge -F ) bond was (2.99 ev)
instate of that the vibration modes of GeF4 and frequency in IR spectra region
because variable of dipole moment for molecule. Also we calculated
Thermodynamic properties for GeF4 such as Heat of formation , Enthalpy , Heat
of Capacity and Entropy Were (-290.231 kcal/mol , 4198.48kcal/mol , 19.61
kcal /k/mol , 82.25 kcal /k /mol,) respectively all at room temperature and one
atmosphere ( 298 k , 1 atm.) , and we calculated this properties at various
temperature from ( 100 – 3000 ) K . The calculated results are in a good
agreement with experimental results

Thinking Skills in Architectural Work A Study of Thinking Skill Levels at Student of Architecture

Engineering and Technology Journal, 2011, Volume 29, Issue 3, Pages 125-152

A skill is the learned capacity to carry out pre-determined results often with
the minimum outlay of time, energy, or both . Skills can often be divided into
domain - general and domain - specific skills . An architect should ideally be a
person possessing large variety of skills and capabilities like : good
communication, shows strong drawing able to solve problem, capable in abstract
thinking and seeing the wider context of things and believes in collaboration. In
practice, architects usually are good at technologies, project work, but in the
previous studies they seem a lacking of framework knowledge about thinking skills
and their levels in architectural education , and that what the research problem
concentrates on .To achieve this it is necessary to : formulate conceptual
framework about thinking skills which consists of three layers : first, the nature of
thinking (kind and its direction), second productive thinking strategies , and third
the necessary skills to fulfill the design process which consists of eight skills , and
the application focuses on four ; focusing skills, organizing skills, analyzing skills
and generating skills which applied on texts written by the students themselves .
This paper shows that the significant skill was focusing skills, where the students attending to selected piece of information and ignoring others by well defining
problem .