University of Technology-IraqEngineering and Technology Journal1681-690029920110601Performance Changes For Window Type Air-Conditioner Unit Chemically Treated To Work In An Industrial Petrochemical Environment4304473178210.30684/etj.29.9.19ENJournal Article20110601Since most of our industrial applications suffer from aging of units. and hence<br /> the penalty of gaseous harmful releases with bad corrosive influences on airconditioning<br /> components. However all the available solutions to diminish these<br /> influences are related to painting parts of the air-conditioning system with different<br /> substances and methods. The present study investigates the effect of chemical<br /> painting on the performance of these air-conditioning units. This research is a<br /> practical study which explores the influence of a specified kind of chemical<br /> painting used to paint Aluminum fins and copper pipes in the refrigeration system<br /> for window type air-conditioning units of (2tons capacity-reciprocating compressor<br /> -R-22) on it’s performance through calculating each of the capacity of<br /> refrigeration, compressor work, transmitted heat and coefficient of performance<br /> before and after the chemical painting process, and making comparison between<br /> the two in various operating conditions. It was found that the coating causes a<br /> decrease of the capacity of refrigeration, compressor work, transmitted heat and<br /> coefficient of performance. However it saves all parts in refrigeration system from<br /> corrosion for along time. The practical part were conducted in the state company<br /> for electrical industries.https://etj.uotechnology.edu.iq/article_31782_71a4d6dcac38548094fe61d883918717.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-690029920110601Influence of The Air Flow In The Induction System On The Performance Of A Reciprocating Air Compressor4484623178610.30684/etj.29.9.20ENJournal Article20110601The aim of this work is to study the effect of the flow in the induction system on<br /> the reciprocating air compressor performance. The study was carried out on the<br /> reciprocating air compressor with two cylinders and three stages. The cooling<br /> between two cylinders occurs by the air and used three pipes with different length<br /> and diameter. A mathematical model is presented to calculate the pressure,<br /> temperature, volume, mass and volumetric efficiency. This model depends on the<br /> Runge-Kutla method to solve the differential equation system. The result show that<br /> when used the multi – stage air compressor increases as result of efficiency air<br /> cooling , the length and diameter of the induction pipe and velocity of compressor<br /> have a significant influence on the compression wave capacity also the final<br /> pressure generated in compression space which caused to increase the volumetric<br /> efficiency .https://etj.uotechnology.edu.iq/article_31786_b11fc55f5c1770fb49edea3411257bb4.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-690029920110601Study Some Physical and Mechanical Properties of Ceramic – Ceramic Fibers Composite163116403168610.30684/etj.29.9.1ENFadhil Attiya ChyadJournal Article20110601Zirconia fibers have been prepared by convertional method using cotton threads<br /> impregrated in zirconium oxychloride solution ( ZrOCl2. 8H2O ). X-ray<br /> diffraction shows the crystallinity of zirconia and optical microscopy shows the<br /> fibers fabrication. Differnet percentage ( 2 ,4 ,8 , 10 and 12 ) of prepared zirconia<br /> fibers mixed with ZnO powder.<br /> All the specmen sintered at 1250 °C for 2hrs. Physical properties (density and<br /> volume shrinkage) were measured and Mechanicl properties (Vicker ̉s<br /> hardness,fracture strength and fracture toughness by indentation method ) were<br /> calculated, 10% of fiber content has the maximum values for these properties for<br /> the composite.https://etj.uotechnology.edu.iq/article_31686_460441405246e30c7b7c6995ced5c162.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-690029920110601Microstructure and Hardness Effects on Behavior of Copper Alloy under Creep – Fatigue Interaction164116503169010.30684/etj.29.9.2ENMairb R. Abdul HassanJournal Article20110601The microstructure and hardness of copper alloy after fatigue-creep interaction<br /> testing have been investigated. Experiments were carried out in the temperature<br /> range from room temperature to 300oC. Attention has been paid to the role of the<br /> microstructure and hardness on the fatigue-creep strength of copper alloy. It has<br /> been shown that, there is a little effect of microstructure in the cyclic response of<br /> copper alloy, while the hardness has a significant effect on the fatigue-creep<br /> strength. The relation between strength and hardness were described by the<br /> following equation:<br /> σE.L. = 5.345 H0.6217https://etj.uotechnology.edu.iq/article_31690_9b81367921783a09cf98e2131495809f.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-690029920110601Expansion Methods for Solving Linear Integral Equations with Multiple Time Lags Using B-Spline and Orthogonal Functions165116613169310.30684/etj.29.9.3ENAtheer Jawad KadhimJournal Article20110601The main portion of the paper is devoted for constructing approximated<br /> solutions of linear integral equations with multiple time lags (IEMTL) using two<br /> different types of basis functions B-spline functions and Orthogonal functions<br /> containing (Laguerre and Hermite) with the aid of expansion methods (collocation<br /> method, Partition method and Galerkin’s method). Algorithms with the aid of<br /> Matlab language are derived for treating these equations using expansion methods.<br /> Comparison between the exact and approximated results of these methods with the<br /> aid of basis functions are given via two test examples and accurate results are<br /> achieved.https://etj.uotechnology.edu.iq/article_31693_32bc800c45abca7510f9d7398c83859c.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-690029920110601Mathematical Technique for Controlling the Gaps in the Cubic Bezier Curves for Two Dimensional166216723169910.30684/etj.29.9.4ENAli Hassan HammadieJournal Article20110601Designs are generated in the Bezier curves at most contains gaps in form that is<br /> drawn up in curve. This state is causing misshaping final form that depended on<br /> curves generating.<br /> In this research applies of suggested method is making Bezier curve generating<br /> don't contains upon gaps and can controlled to eliminate gaps by using added<br /> parameters to control it.<br /> The research applies modified equations by using different shapes in different<br /> cases and brought shapes (curves) don't contain the gaps and smoothing curves' .https://etj.uotechnology.edu.iq/article_31699_9d353dd64635928089d5063acf51f9b7.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-690029920110601Galvanic Cathodic Protection Evaluation of a Steel Pipe in Iraqi Soil167316903170310.30684/etj.29.9.5ENJafer T. Al-HaidaryMohammed H. HafizYasir Muhi Abdu Al-SahibJournal Article20110601Corrosion is the main problem for the embedded pipelines in different<br /> environment resistivities. The most effective method to overcome this problem is<br /> cathodic protection which represents as a control method of the pipe corrosion.<br /> For achieving longer life of the external corrosion control system and evaluating<br /> the performance of aluminum alloys which have been used as sacrificed anodes<br /> to protect the embedded carbon steel pipe in different artificial simulated<br /> resistivity of soils in Iraq of [5000 , 1000 , 600 , 50 and 25 (Ω.cm)]. Results show<br /> that (Al-10 wt% Zn) as sacrificial anode alloy has the best anode capacity<br /> compared with other anodes under these conditions (Al-5 wt% Zn), and (Al-15<br /> wt% Zn). The selection for these alloys based on that they have high potential in<br /> many environments when coupling with steels without effect of microbial,<br /> obstacle and stray current. The polarization curves of alloys also show no<br /> passivation behavior in artificial resistivities. The corrosion rate of different anode<br /> alloys was determinated as a function of applied cathodic protection.<br /> It was found a relationship between electric potential and time which<br /> determine the optimum potential in different soil types for the three above selected<br /> electrodes (anodes).https://etj.uotechnology.edu.iq/article_31703_7f2903017722befd51e62ccc4b6a2302.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-690029920110601The Study of Typical Conditions to Remove Co from Water by Adsorption by Using Activated Carbon169117003170510.30684/etj.29.9.6ENShaymaa H. KhazaalJournal Article20110601The effective removal of heavy metal ions from water is among the most<br /> important issues for many industrialized countries. The present work has been<br /> carried out to study the adsorption of cobalt [II] ion using activated carbon.<br /> The removal of cobalt ions was investigated in batch conditions. The influence of<br /> initial cobalt ion concentration, pH, adsorbent dose, adsorbent practical size;<br /> contact time and shaking rate were studied at room temperature. The analysis of<br /> residual Co [II] ions was determined using Atomic Absorption Spectrophotometer<br /> GBC 933 plus. The results showed that the percentage adsorption of activated<br /> carbon increases with time and that maximum adsorption was obtained within the<br /> first 60 minutes of the process, and 300 rpm shaking rate.<br /> The experiments showed that the maximum % adsorption of 100% was obtained<br /> at adsorbent dose=0.4 gm, pH=13, particle size= (0-75) μm and 10 mg/L of initial<br /> concentration of cobalt. These results indicate that activated carbon has potential<br /> for removing cobalt ions from water.https://etj.uotechnology.edu.iq/article_31705_c24cdec71b19d9014e46e6f7ab8387ba.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-690029920110601The Effect of Filler Type on the Hot Mix Asphalt Behavior170117203170710.30684/etj.29.9.7ENSady Abd TayhAqeel Raheem JabrJournal Article20110601The test have been done on many samples of Hot Mix Asphalt using many types<br /> fillers like Portland Cement, Limestone, Hydrated Lime as a filler, 1% Hydrated<br /> Lime added to conventional mixture, Portland Cement introduced in cold state,<br /> and passing sieve no.200 dust (conventional mixture).<br /> In this research, Marshall test procedure is used to investigate the potential<br /> prospects to enhance Hot Mix Asphalt properties. The objectives also include<br /> determining which one of the additives is better than the others to be used and the<br /> method of introducing this filler type to the mixture.<br /> According to the results, we found out that the better filler affects the<br /> mechanical properties of Hot Mix Asphalt is Portland cement when it introduced<br /> with the aggregate at the mix temperature.https://etj.uotechnology.edu.iq/article_31707_19dc75aac201185c5e6b6f7440bb471a.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-690029920110601Numerical Study of Entropy Generation in a Vertical Square Channel Packed with Saturated Porous Media172117363171310.30684/etj.29.9.8ENAbdulhassan A. KaramallahWahid S. MohammadWissam Hashim KhalilJournal Article20110601Entropy generation in a vertical square channel packed with saturated porous<br /> media, and subjected to differentially heated isothermal walls has been<br /> numerically investigated.<br /> The effect of Darcy, Reynolds, and Eckert numbers on Entropy generation was<br /> studied. The entropy generation was found to be inversely proportional to both<br /> Reynolds and Darcy number, while it was directly proportional with the Eckert<br /> number.<br /> It was shown that as Darcy and Reynolds numbers were increasing, the Bejan<br /> number decreases, i.e., the irreversibility due fluid friction is dominated, while as<br /> the Eckert increases, theirreversibility due to heat transfer increaseshttps://etj.uotechnology.edu.iq/article_31713_a9458e58767f7482cc298bda83c47531.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-690029920110601Sensorless Vector Control of Three Phase Induction Motor Based on Full Neural Estimator and Controller173717503171610.30684/etj.29.9.9ENFatma H. FarisJournal Article20110601Conventional vector control of A.C drives are widely used in industry and<br /> many other applications, where high dynamic performance is required, this type of<br /> controller usually needs costly speed sensor. Sensorless vector control is strongly<br /> recommended in the dangerous sites and hostile environment, also to reduce cost<br /> and increase reliability. In this way the rotor speed can be estimated from the<br /> terminal voltage and current by means of DSP microprocessor. The DSP-estimator<br /> is very complex hardware, has many operation problems, and very sensitive to the<br /> electromagnetic interference (EMI). This paper proposes using the Artificial<br /> Neural Network (ANN) to estimate the rotor speed, flux vector, torque, and unit<br /> vectors instead of DSP-estimator. Also, the neural-based controller is proposed<br /> too. The ordinary vector control with speed sensor and sensorless vector control<br /> based on DSP-estimator PI-controller are represented in this work as point of<br /> comparison. Also, the mathematical representation and simulation of the three<br /> phase induction motor is illustrated in this paper. The proposed method, neuralbased<br /> sensorless vector controller and estimator, gives superior performance in<br /> different speed with respect to DSP-estimator PI-controller.https://etj.uotechnology.edu.iq/article_31716_f328f2ea5f7b211e612ba075c9555632.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-690029920110601Application of GIS for the Evaluation of Electromagnetic Field Effects for Iraqi 132KV Electrical Transmission System175117643171910.30684/etj.29.9.10ENAfaneen A. AlkhazrajiSuad I. ShahlJournal Article20110601This research endeavors to create the 50Hz electromagnetic field atlas for<br /> populated urban areas in the city of Baghdad (Iraq). For this purpose, the 3-<br /> dimensions numerical model based on finite element method (FEM) with time<br /> harmonic system is used for simulated and modeling electric and magnetic fields<br /> surrounding the 132kV transmission system. The calculated magnetic and electric<br /> field levels are compared to exposure guidelines given by International Commission<br /> on Non-Ionizing Radiation Protection (ICNIRP). To assign the dangers regions in the<br /> city, the properties of the Geographical Information System (GIS) were used. The<br /> GIS map highlighted visually the unsafe zones and facilitate the extraction of the<br /> electric and magnetic field levels of exposure.https://etj.uotechnology.edu.iq/article_31719_eb23020b767e0b565337836e3dfcc898.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-690029920110601Ceramic Filled Polymer Matrix Composite Used For Bio-Medical Application176517733172610.30684/etj.29.9.11ENWaleed Asim HannaAbbas Khammas HusseiHayder Abbas SallalJournal Article20110601Synthetic polymers such as polyurethane are used widely in the field of<br /> biomedical applications such as implants or part of implant systems.<br /> This work focuses on the preparation of base polymer matrix composite<br /> materials by (Hand Lay-Up) method ,and studying the effect of selected weight<br /> fractions (3 , 6 , 9 , 12 ,15) % wt of Calcium oxide (CaO) , Calcium carbonate<br /> (CaCO3), Magnesium oxide (MgO) ,and Magnesium carbonate (MgCO3) particles<br /> on some properties of the prepared composite.<br /> Some mechanical tests were used to evaluate the prepared system (Tensile,<br /> Compression, Impact, and Hardness) tests, and a physical test of (Water<br /> absorption %), and all tests were accomplished at room temperature.<br /> maximum results of tensile strength, compression strength, impact energy,<br /> hardness, water absorption were ( (31 MPa),( 51 MPa),( o.265 J), (79.8 Shor (D)),<br /> (0.229 %)) at using ( (9% wt (MgCO3)) , ( 9% wt of (MgCO3)) , ( 9% wt of<br /> (CaCO3)) , ( 15% wt of (MgO)) , ( 15% wt of (MgCO3)) respectivelyhttps://etj.uotechnology.edu.iq/article_31726_3b75a5b14a5dbdbecd6b48fcaa4b9117.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-690029920110601Cutting Forces Prediction in Ball End Milling177417893176510.30684/etj.29.9.12ENHussain S. KitanBahaa I. KadhimSusan A. AbdulrazzaqJournal Article20110601In curved surface machining, parametric surface representation is normally used for computer aided design (CAD). Parametric surfaces are often machined using a flat end mill for roughing and ball end mill for finishing. The core of this work is to propose and implement a model that is able to estimate the cutting force in milling parametric surfaces with HSS ball end cutter of different diameters. For this purpose, a mechanistic model has been developed to calculate the cutting forces by dividing the cutting edge into small discrete<br /> elements and applying simple mathematical expressions for the cutting force estimation, once the force of each discrete element is calculated, these elements summed up along the cutting edge to obtain the resulting cutting force. The slope (inclination angle α) of the surface was included to the model to estimate the influence of ifferent conditions of the slope ( - 90o ⟨ a ⟨ +90o ) which most parametric surfaces included. The results showed that the predicted results deviate<br /> from experimental by (0.6-11 %) for Fx, by (2-10 %) for Fy and by (0.18-14 %) for Fzhttps://etj.uotechnology.edu.iq/article_31765_3a446d763ae5020ff9fd948589fcbba4.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-690029920110601On Fuzzy Normed Spaces179017953176810.30684/etj.29.9.13ENJehad R. KiderJournal Article20110601In this paper we introduce a new definition of a fuzzy normed space (to the best<br /> of our knowledge) then the related concepts such as fuzzy continuous,<br /> convergence of sequence of fuzzy points and Cauchy sequence of fuzzy points are<br /> discussed in details.https://etj.uotechnology.edu.iq/article_31768_1762382c5031a811d0ecb8c933127aab.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-690029920110601Number of Quantum Well(s) Effects on GaN-Based VCSELs179618033176910.30684/etj.29.9.14ENFarah Z. JasimJournal Article20110601Advanced numerical simulation program was used to analyze the performance of GaN<br /> based vertical cavity surface emitting laser (VCSEL) with single, double and triple<br /> quantum well(s) as active region. It was found that numbers of quantum well (QW)<br /> variation inside the active region is the most critical factor on the VCSEL performance.<br /> The lowest threshold current and highest in both the slope efficiency and differential<br /> quantum efficiency were observed when the well number is double (DQWs) at 415<br /> nm VCSEL. This is ascribed to that for single quantum well (SQW), some of the gain<br /> begin to escape before lasing is achieved while for triple quantum wells (TQWs) while<br /> are separated by many thick barriers, then transport carriers between wells will be<br /> inefficient. As a result, a non-uniform carrier distribution may result.https://etj.uotechnology.edu.iq/article_31769_8366924b545c3df887180b68ecc6c32b.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-690029920110601A Study Mechanical Properties of Epoxy Resin Cured at Constant Curing Time and Temperature with Different Hardeners180418193177110.30684/etj.29.9.15ENNajat J. SalehAdnan A. Abdul RazakManal A. ToomaMariam E.AzizJournal Article20110601In this study, a low molecular weight epoxy resin diglycidyl ether of bisphenol A (DGEBA) is cured isothermally with an aliphatic and aromatic amine hardeners separately. (1) Triethylenetetramine (TETA), (2) diamino diphenylmethane (DDM). The samples were prepared for different hardener/resin ratios, (under stoichiometry, stoichiometry and above stoichimetry). The mechanical Properties impact strength, tensile strength, hardness, flexural strength, compression strength and bending strength of an epoxy system has been investigated in this work. For DGEBA/TETA system the tests were done on four hardener/resin ratios (10, 13, 15 and 20) phr and for DGEBA/DDM system the hardener/resin ratios were four also; (24, 27, 30 and 34) phr. The results showed<br /> that the above stoichiometry ratio formulation (15 phr for DGEBA/TETA system and 30 phr for DGEBA/DDM system) gave the best mechanical properties, while the DGEBA/DDM system showed better mechanical properties than the DGEBA/TETA system.https://etj.uotechnology.edu.iq/article_31771_e7e4654bff51c1a4a1d2d5f33bf2d496.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-690029920110601The Primary Decomposition of the Factor Group K(G)182018293177310.30684/etj.29.9.16ENManal N.AL-HarereFuad A.AL-HeetyJournal Article20110601The main purpose of this work is to find the primary decomposition of the factor<br /> group K (The factor group of all Z-valued class<br /> functions module the group of Z-valued generalized characters for elementary Abelian<br /> group G), where G is a finite Abelian group of type , p=5.<br /> This work depends on finding the rational valued character matrix<br /> from the character table of and finding the invariant factors of this matrix, also we<br /> found the general solution of this decomposition and prove it by mathematical<br /> induction. We have used the MATLAB program to calculate some results of this<br /> work.https://etj.uotechnology.edu.iq/article_31773_2e6411ac346bf88fa08123a3af290eaa.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-690029920110601Numerical and Experimental Investigation of Mechanical and Thermal Buckling Loads of Composite Laminated Plates183018443177610.30684/etj.29.9.17ENAmmar A. HusseinHassan H. MahdiNessren H. AhmedJournal Article20110601In this study, the effect of temperature, aspect ratio, number of layer and<br /> boundary conditions on critical buckling load of composite laminated plate is<br /> investigated experimentally and numerically. Simply-Simply-Free-Free and<br /> Clamp-Clamp-Free-Free boundary conditions, three temperatures (40°C, 60°C and<br /> 80°C) and four aspect ratio (1, 1.3, 1.5 and 2) will consider for the experimental<br /> work. The thickness of the plate was changed by increasing the number of layer.<br /> It can be seen that when the temperature changes from 40°C to 80°C the<br /> maximum value of Pcr is about (225 N/mm) at (T = 40°C, a/b = 2 and NL = 4), the<br /> minimum value of Pcr is about (11.70 N/mm) at (T = 80°C, a/b = 1 and NL = 2).<br /> Also, it can be shown that in the case of symmetric cross ply laminate (0o/90o/0o)<br /> when the thermal load increased by about 100 % the buckling load decrease by<br /> about 50 % at aspect ratio equal to 1. Finally, It is shown that the critical buckling<br /> load increases with increasing the aspect ratio at constant temperature, number of<br /> layers and boundary conditions.https://etj.uotechnology.edu.iq/article_31776_4b121fcd31f0e008d8935467e3470982.pdfUniversity of Technology-IraqEngineering and Technology Journal1681-690029920110601Determination of the Adequate Thickness of Granular Subbase Beneath Foundations184518693177910.30684/etj.29.9.18ENMohammed Y. FattahFalah H. RahilMohammed A. TurkiJournal Article20110601Where the native soils have poor structural qualities or are expansive, the soil<br /> investigation report may recommend importation of soils better suited to providing a<br /> subbase for structures. This requires considering two soil layers in bearing capacity<br /> calculations.<br /> Calculation of the ultimate bearing capacity of shallow footing on a two layered system<br /> of soil depends on the pattern of the failure surface that develops below the footing. For a<br /> weak clay layer overlaid by a top dense sand layer, previous studies assumed that the<br /> failure surface is a punching shear failure through the upper sand layer and Prandtl's<br /> failure mode in the bottom weak clay layer.<br /> In this paper, the bearing capacity of subbase layer underneath by a soft clay layer is<br /> investigated. The properties of the subbase material are measured in the laboratory.<br /> Design charts were obtained which can be used to select the suitable thickness of the<br /> subbase layer for a design allowable bearing capacity.https://etj.uotechnology.edu.iq/article_31779_b37d35890419e2041de40669e9edc7d2.pdf