Print ISSN: 1681-6900

Online ISSN: 2412-0758

Issue 12,

Issue 12


An Investigation of Natural Convection Heat Transfer in a Square Enclosure Filled with Nanofluid

Ayad M. Salman

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 2346-2363

In this research, numerical solution of natural convection heat transfer of nanofluids in two-dimensional square enclosures is obtained for different values of Rayleigh numbers and volume fraction of nanofluids. Numerical simulation has then been undertaken for the mixture of Cu-water as nanofluid. The stream–vorticity form of the Navier–Stokes equations and energy equation are used in this study. The present model is utilized to obtain results in the range of Rayleigh number 103–105 and volume fractions of nanofluids (0.025-0.1). The enclosure which represent two-dimensional square enclosure with heated left side wall, while the right side was cold, the top and bottom walls were adiabatic. The governing equations are solved with finite-difference technique by central difference scheme. A computer program in (FORTRAN 90) was used to carry out the numerical solution. The results are a remarkable increase in the average Nusselt number with an increase in the volume fraction. An increase in the Rayleigh number results an increase in the average Nusselt number for a certain nanoparticle. In order to validate the numerical model, the results of two previous works for square enclosure filled by water based Al2O3 nano-particles as nanofluids. The first work was variation of average Nusselt number and volume fraction for Ra number Ra=103. There are excellent agreement in results and the maximum difference between these results reach 4.2%. A relation between average Nusselt number and Ra number also compared for other previous work. There are agreement in results and found the maximum difference between results reach to 6.5% approximately at Ra=105 which validate the present computational model.

Implementation Of 3D Virtual Poetry Image By Using Bezier Cubic Splines And Open GL Primitives

Monem S. Rahma; Abd Al; Luma Faik Jalil Khalil

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 2364-2374

This paper presents suggested algorithm to draw or generate a 3D virtual poetry image from Arabic poetry text. Bezier curves had been used to generate this image depending on some computed values named appearance rates which is defined and evaluated from the poetry text. Those defined values have a great effect on poetry image generating where those values represent the control points which they are used in Bezier cubic function. Bezier cubic and triangle primitive had been used to implement the poetry image. Many poetry segments written by different poets had been taken as samples to test the suggested algorithm.

Al - Kalij Sub-Station: Feeder Reconfiguration by Particle Swarm Optimization

Qais M. Alias; Rana Ali Abttan

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 2375-2385

This paper presents the solution approach for the optimal reconfiguration problem
in distribution networks implementing Particle Swarm Optimization (PSO)
technique.
Network reconfiguration in distribution system is changing the status of
sectionalizing switches to reduce the power loss in the system. The main objective of
network reconfiguration is to find the network topology which is having the
minimum losses during any conditions exists in the network. A network
configuration is a valid solution to the problem if it satisfies reliability, security and
other operation constraints.
Particle Swarm Optimization is a robust stochastic evolutionary computation
technique, which is based on the movement and intelligence of swarms.
A standard particle swarm optimization algorithm is adapted and used in this work.
The primary case study is a part of the Baghdad area distribution network. It consists
of four feeders and 102 buses. The algorithm validity is verified first via application
to standard systems. Results show that the standard particle swarm optimization is
suitable for off-line reconfiguration studies.

Non-Sinusoidal Loading Effect on Oil Immersed Power Transformers

Mohammed k.Edan

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 2386-2400

Transformers are usually designed for nominal frequency and sinusoidal load current. Nowadays, usage of non-linear loads such as power electronics loads has extremely increased. These loads produce harmonic currents, which induce additional losses in transformer windings and other transformer parts and cause temperature rise, and ultimately can cause insulation deterioration, ageing and finally fast failing. The purpose of this paper effort to quantify the increasing in transformer
losses due to harmonic load current and the corresponding temperature rise in
transformer and study the effect of harmonics on loss of insulation life, total ownership cost of transformer, capacity of transformer and oil viscosity. An eddy current harmonic loss factor for transformer windings and harmonic loss factor for other stray loss are presented and used to calculate the transformer losses under harmonic load currents. The impact of transformer winding conductor size on
winding eddy current harmonic loss factor is presented. Three loads with different amount of harmonic content of load current are proposed in this paper.

Enhancement of Iraqi National Grid Stability using Power System Stabilizers

Kosay A. Majbor; Hayfaa M. Al- Rudayni

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 2401-2413

In general, electrical power stations are constructed far from load regions because of pollution problems and using long transmission lines for high voltage. Also, the networks are connected with other networks for the purpose of transmission and to return supply the electrical energy. As a result, and because of other factors, such as sudden change in the load, oscillations occur in electrical systems, some time, these oscillations become strong and if they continue they will affect stability system.
This work is devoted to the study of the stability of the Iraqi National Grid when subjected to various operating conditions (fault: large and small load changes). Load changes produce low frequency oscillations which represent an unstable phenomenon, it is important that these oscillations are damped. Supplementary controllers (power system stabilizers, PSS type 2A) may be added to the generators controllers to improve the damping of these oscillations. Part of the work will be focused on studying the oscillation in the generators torque angles of the Iraqi Grid. Three cases of disturbances are investigated; the first is load changing, the second is Single-Line-Ground fault, and the third is three phase fault at the generator terminals.

Mean Drift Length During a Semi Wave of the CW Radio-Frequency Field

Ibrahim K. Fayyadh; Muhammad I. Ismaeel; Kasem R. Ali

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 2414-2438

In this work we study mean drift length during a semi wave of the CW radiofrequency field the behavior of the diffusion particles in the pure Helium gas whose plays important role in production of the lam
ps such as glow lamps and gas lasers through the calculation of the transport parameters which are w, μ, and D by solving numerically transport equation and feeding it to computer program which is construction to calculate the following parameters: E/P300, S, DN, Dp, n, c , l, w, a, SE, (fn1P), (fn1P)-1, w/p and p/w for energy ranges 0.121´10-18 £ E/N £ 0.303 ´10-16 V.cm2 at temperature 300°K.
These parameters represented as functions for their variables whose shows a good agreement with experimental and theoretical data.

Harmonics Study of 3-Phase Space Vector PWM Inverter

Ahamed Assad Hadi; Majid K. Al-Khatat

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 2439-2455

This paper proposes the modeling ,implementation and simulation of three phase induction motor driver, using voltage- fed space vector pulse width modulation technique (SVPWM).The sources of total harmonics (i.e. total effective harmonics,inter-harmonics,and sub-harmonics) and how it affects on drive system and their affects on the supply power network are studied. A developed formula of total harmonics distortion factor (THD) including ,inter -harmonic, and sub- harmonic has been introduced while in the previous studies are neglected. The effect of inter-harmonics and sub-harmonics on the performance parameter of total harmonics distortion factor , switching losses factor (SLF) and quality factor (QF) has been deduced. Modeling , and simulation of the system using PSIM software are also presented. All results are obtained by studying the waveforms of voltage and current at the source and load sides with different speeds of motor drive. The simulation and experimental result are consistent with theoretical studies and excellent , they indicate that the model is accurate and practicable.

Experimental and Theoretical Study of Square Deep Drawing

Karem Muhsin Younis; Adil Shbeeb Jaber

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 2456-2467

This work aim to study the effect of process parameters used in square deep
drawing operation such as ; die and punch profile radius, blank size, blank shape, on
produced cup wall thickness, strain distribution across the wall of the drawn part,
punch force, earing shape and height of the drawn cup. 3-D model of square cup
(41.4mm by 41.4mm), and 0.7 mm thickness from Low carbon steel (AISI 1008), has
been developed. Because of the symmetry in the specimen geometry, only one fourth
portion of the model was needed to be analyzed using finite element method, a
commercial available finite element program code (ANSYS 11), is used to perform
the numerical simulation of the deep drawing operation, and the numerical results of
earing shape were compared with the experimental work. In this work, three types of
blank shape (circular, square, and octagonal), with different sizes, four types of punch
profile radii of 3, 5, 6, and 7mm and three types of die profile radii of 3, 5, 7mm have
been chosen to form a square cup. The results show that, excessive earing will appear
in the square cup when square blank was used, due to excessive material in the corner
and minimum material in the flat side, and when using octagonal blank which have an
equivalent surface area to the square blank, the earing in the cup corner is reduced
because of extraction of the excessive material from the corner of the blank. The best
results were obtained from the circular blank, according to useful drawing height and
earing.

Effect of Crack and Cutout on Vibration Characteristics of A Laminated Composite Plates Using Nonlinear Finite Element Analysis

Nabil Hassan Hadi; Kayser Aziz Ameen

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 2468-2490

A nonlinear finite element model for geometrically large amplitude free vibration analysis of composite laminated plate using high order shear deformation theory used in this work. The aim of the study is to analyze the effect of the stationary crack and hole on the free vibration of composite plate those in which the singularity due to presences of crack is modeled, so that stress field at the tip of the crack is properly represented. The results are computed for different crack, hole size, material orthotropy and different boundary condition. Finally the discrepancy of the results was 29.8249% when considered the severe nonlinearity.

Proposed System for HTC Phone Data Management

Alaa Kadim; Hasanen S. Abdullah

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 2491-2500

In the last years the electronic networks were used in several practical field of life. The mobile networks is considered one of the important and powerful type of these networks, that have wide area of using in the electronic life, such as financial application, electronic learning, remotely management and basic role in information management field. In this paper a new system is proposed that can work to protect the customer information in the mobile devices and manage it through network server. The idea is based on design and builds a system for information management especially to each customer (such as bank system), and then display this information on the customer mobile device after an authorized connection with the manager of the system database and request the information. The customer information must be secure enough, therefore one of the proposed system tasks is to protect the information of each customer, this task is done by using a block cipher method(DES). The proposed system provides another task that is the basic operations which the manager of the system database can do such as add, delete, update, and so on. The system is implemented by using VS.net with a database of type .sdf which is especially used in the mobile applications and implement it in the HTC(High toxicity clastogens) smart phone mobile.

Polymeric Additives Effect on Mechanical Properties for Bitumen Based Composites

Khalid M. Eweed

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 2501-2519

Bitumen binder is a thermoplastic liquid and the elementary analysis of the bitumen manufactured from a variety of crude oils shows that most bitumen contains carbon, hydrogen, sulphur, oxygen, and nitrogen. At high temperature or low loading, it behaves as a viscous liquid. This classical dichotomy creates a need to improve the performance of an asphalt binder to minimize the stress cracking that occurs at low temperatures and the plastic deformation at high temperature. In order to increase the durability of bitumen materials are needed to modify the quality of bitumen materials. The research work covers five percentages of thermoplastic copolymer content (5%, 7%, 9%, 11%, and 13%) by weight of bitumen were used. The polymer modified mixes were designed in accordance with Marshall Test. Experimental testing has revealed the enhancement in the physical and mechanical properties of bitumen mixtures when the five percents of the thermoplastic copolymer were added. The ethylene vinyl acetate (EVA) modified bitumen had the lowest penetration and highest kinematic viscosity as compared with that of unmodified bitumen. The ethylene vinyl acetate (EVA) modified mixtures also has experienced the highest Marshall Stiffness, indirect tensile strength and unconfined compressive strength as compared with that of unmodified mixtures. The experimental results are used to develop four empirical correlations. The practical use of such equations, given the value of the mechanical properties with the polymer and bitumen content without needs any experimental data points.

Statistical and Visual Analysis of Error In Interpolating Sculptured Surfaces

Tahseen F. Abbas; Aqeel S. Baden; Muhamed A. Salih

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 2520-2538

This paper presents a general method for automatic surface interpolation from
range data and describes the implementation of high order 2D langrangian methods
for interpolating surfaces from 3rd to 8th order. It uses a modified 2D lagrangian
method to interpolating, reconstructing and modeling several surfaces, and due to this
interpolation there will be an error between interpolated surface and the original one,
this paper present an algorithm to detect, represent and analyze these interpolating
errors and statistical criteria to compare the error in representing the sculptured
surfaces that interpolated with different order basis functions. The comparison is
performed using a mathematically defined data as real data obtained from the
proposed models.
The system has been implemented for the design of several sculptured surfaces to
illustrate the system flexibility. Then the design results have been implemented for
manufacturing two of these surfaces using three axis vertical CNC milling machine
tool with ball end mill cutter. The method can be used in a variety of CAD/CAM
applications and it has proven to be effective as demonstrated by a number of
examples using real data from mathematical functions. By applying the proposed
surface interpolating models the percent error was found to be ranged between
0.00001% for some model to 3.5% for some other interpolated models with Lagrange
method.

Particle Swarm Optimization for Total Operating Cost Minimization in Electrical Power System

Mohammed H. al-khafaji; Shatha S.Abdulla al-kabragyi

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 2539-2550

This paper presents solution of economic dispatch problem via a particle swarm optimization algorithm (PSO). The objective is to minimize the total generation fuel cost and keep the power flows within the security limits. The PSO is simple in concept, easy in implementation .It does not require any derivative information, sure and fast convergence, Moreover; it is needs less computational time than other heuristic methods. These features increase the applicability of the PSO, particularly in power system applications .The effectiveness of the proposed algorithm is demonstrated on the IEEE 37-bus system and their performances are compared with the results of genetic algorithm (GA). The results show that PSO can converge to optimum solution with higher accuracy in comparison with GA.

Image Encryption using Resilient Boolean Function and DCT

Hussam A. Darweesh; Ekbal H. Ali; Azhar Malik

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 2551-2563

The information security is becoming more important in data storage and transmission, where images are widely used in it. The Stream cipher cryptosystems are extensively used for provide a reliable and efficient method of security. The new propose system image encryption investigated by encrypt the powerful frequency coefficients in DCT by used saturated best resilient Boolean function that constructed by Zhang's constructions that implement Maiorana-McFarland like constructions technique and its modifications. The simulation results of the proposal system calculate correlation test (Corr1) and PSNR1 to compare between original and encrypted image as parameter of robustness, and correlation test (Corr2) and PSNR2 as correlation parameter between original and decrypted image as parameter of quality in reconstruct image.

Studying and Modeling The Effects of Quartz Addition and Heat Treatment on Corrosion Properties of Ceramic Coating

Ali H. Ataiwi; Ibtihal A. Mahmood; Jabbar H. mohmmed

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 2564-2579

In this work, a new glass-ceramic coating has been developed and applied, as a single coat without prior chemical treatment of the surface, by using the dipping technique on metal substrate. the coating are designed for application on varies grades of low alloy steel, the selected substrate was low carbon low alloyed steel with (0.2)%C. Various heat treatments at temperatures ( 500,550, and 600˚C ) at different times (60 & 120)min and with quartz addition in the range (0-15)% were used to obtain a glass-ceramics that have the optimum coating properties. These coating have been characterized by x-ray diffraction analyses and the results showed presence of a number of microcrystalline phases which are formed during the heat treatments. The results of corrosion resistance tests indicated that the acid resistance was greatly improved by addition of quartz into enamel frit but at same times decreased the alkali corrosion resistance, while the heat treatments improved both acid and alkali resistance for all cases, this is attributed to the formation of complex network from crystalline phases. The results also indicated that the heat treatment at 600˚C for 120min with 15% quartz addition brought the optimum values for acid resistance property which are improved by 86.66%, while the optimum values for alkali resistance property was brought with free quartz added samples which were treated at 600˚C for 120min. Mathematical modeling is implemented and regression equations are obtained by using ( SPSS ) software to predict the experimental data for acid and alkali corrosion rate. Comparing the predicted and measured values gives high prediction accuracy. The accuracy of prediction has been (82.58%, and 96.7%) for acid and alkali resistance properties respectively.

Design and Implementation of Microcontroller Based Portable Drug Delivery System

Mohammed Sabah Jarjees

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 2580-2588

Portable drug delivery system or portable syringe pump system is a small infusion pump used to gradually deliver drugs, at low doses and at a constant or controllable rate of drug to a patient who needs to take a drug dose regularly in specific periods all the day. The aim of this research is to design and perform a prototype of a portable drug delivery system controlled by micro controller. The micro controller will control the dose of liquid or medication which will be given to the patient and the time of repetition of the dose. The dose rate will be adjusted by controlling the operation of stepper motor which will drive the syringe pump through fine mechanism set.

Evaluation of Corrosion Resistance of Steel used in Concrete Reinforcement in Aqueous Media

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 497-506

This paper is aimed to study the corrosion resistance of iron which used in concrete layer in aqueous media (Rain water, Sea water, Tap water). Specimens was manufactured as cylinder by (10 x 3 mm) according to ASTM. Corrosion test was implemented by loss weight process in aqueous media (Rain water, Sea water, Tap water) for (1-30) day. Specimen was weighed before and after test. Corrosion rate
was calculated in all media and it was found that all media cases corrosion and corrosion was greater in sea water. Also potential state method was used to find the corrosion rate by using electrical cell the specimen represented the positive electrode. The negative electrode was made of platinum, a potential cell was limited by passing a current in the open circuit. The potential was compared with the potential of the
metal in the electrochemical chain. Then the circuit is closed and an electric current at this potential is passed with an increasing +100 volt , –100 volt, and finding the corrosion current through the intersection contacts to the cathodic and anodic electrode in accordance with Tafel's method and calculation the corrosion rate and
also the results of sea water corrosion is found higher than the other.

The Cytotoxicity Effect of Ethanolic Crude Extract of Petroselinum Crispum on Cancer Cell Line Hela

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 507-517

This study amid to investigate the effects of ethanolic crude extract of Petroselium cripum leaves on the proliferation of the cancer cell line HeLa .
The cytotoxicity of cancer cell line of concentration of (0.95, 1.9,3.8,7.7,15.5,31.25,62.5,125,250,500,1000,2000,3000,4000,6000,8000, 10000, 12000 and 16000)μg/ml showed there was no inhibition observed at concentration (o.95,1.9,3.8,7.7,15.5,31.25and 62.5)μg/ml. While at concentration of 250,500 and 1000 mg/ml the inhibition percentage was less than 50%.But at concentration of 2000 and 4000μg/ml the inhibition percentage was(63%,66%) respectively at while after 48hrs the concentration of (6000,8000,10000,12000,14000 and16000)μg/ml the inhibition percentage was more than70% this study was found that the alcoholic extract hase toxic effect on cancer cell line ,on the inhibition percentage of HeLa cell line was 73.840% and 79.238% at concentration of 6000μg/ml and 16000 μg/ml after 24hrs the percentage79.930% at concentration 6000 μg/ml to 86.505% at concentration16000 μg/ml after 48hrs. exposure and the percentage was 82.353% at concentration 6000 μg/ml to 88.581% at concentration16000 μg/ml after 72hrs .From this result we can conclude that this plant have a promising medical plant effect on cancer,through out the toxic effects on cancer cell line .

Effect of Heat Treatments on The Mechanical Properties And Wear Resistance of Al- Alloy Matrix Composite

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 518-533

Metal matrix composite (MMCs) of the base alloy (Al-0.978%Mg-1.03%Si) reinforced
with SiC particles (10 wt %) with particle size (53-106) μm was prepared by stir casting
using vortex technique. Solution heat treatment and aging are carried out at a constant
temperature of 175C° for different aging times. Many inspections and tests such as
microstructure, Vickers hardness and XRD analysis. Wear test type ( Pin – on – Disc) with
various applied loads and different exposure times at constant parameters was carried out
under dry sliding conditions.
It was found that the addition of SiC particles to base alloy improved the hardness and
wear resistance before and after heat treatment (precipitation hardening).
In addition, using SiC particles with alloy matrix resulted in a faster aging response i.e the
time of peak hardness decreased from 8hr to 5hr for base alloy and composite respectively.
These results indicate that the addition of SiC particles to Al –alloy matrix accelerates the
aging kinetic.

Separation of Iron Oxide from Red Kaolinite

Engineering and Technology Journal, 2011, Volume 29, Issue 12, Pages 534-541

The research aims to separate the Iron oxide from kaolinite by leaching the iron from the ore by using oxalic acid at different Quantities and at different (times, PH). The optimum conditions had been achieved was at morality 1.059 of acid the time was 2 hours &PH 3.2 the grade of iron in the ore was 5.72% and after the separation the iron in the concentrate becomes 1.25% so the percentage of removing Iron from kaolinite ore by this procedure becomes 78%.