Print ISSN: 1813-0526

Online ISSN: 2220-1270

Volume 21, Issue 1

Volume 21, Issue 1, Winter and Spring 2013, Page 1-156


Comparison of some Methods to Estimation Reference Evapotranspiration for Mosul Area(Arbic)

Alaa A.Y

AL-Rafdain Engineering Journal (AREJ), Volume 21, Issue 1, Pages 1-8
DOI: 10.33899/rengj.2013.67339

Abstract:
This study has been established for Mosul area by using climatic data and information for estimation of evapotranspiration by using methods (Blany–Criddle), kharrufa, pan evaporation,Fao penman montieth) and comparison between them to reach to the best method this study showed that pan evaporation equation has a very good determination factor with Fao-penman montieth because this method depend on simple and easily obtained information in comparison with other methods so that this method is a more suitable use for Mosul area also this study showed that there is a correlation performance relationship between these method the value of determination factor for Blany – Criddle is (0.9922) and for pan evaporation is (0.9788) and Kharrofa equation (0.9536) in comparison with Fao-penman Montieth .

Numerical Study of Refrigerant Flow in Capillary Tube Using Refrigerant (R134a)(English))

Dr. Amir S. DawoodAss; Salim Ibrahim Hasan

AL-Rafdain Engineering Journal (AREJ), Volume 21, Issue 1, Pages 1-19
DOI: 10.33899/rengj.2013.67350

Abstract
The present research aims at buildingof a mathematical model using (Engineering Equation Solver) (EES) software to analyze the flow of the refrigerant R134a into two configurations of adiabatic capillary tubes (straight and helical coiled tubes) which are used widely in a household refrigerator, freezer and water cooler. The governing equations which depend on the conservation of mass, momentum, and energy have been coded in order to calculate the length of the single-phase flow region. Moreover, the two-phase regionhasbeen divided numerically depending on homogenous flow assumption after determining the boundary conditions and calculating the physical variables at each point of the numerical divisions by using successive substitution method using iteration loops. Finite difference scheme, the length of thetwo-phase region and the total length for the capillary tube have also been determined. The results show that the behavior of the flow is similar for both forms with regard to the distribution of variables (pressure and temperature drop, dryness fraction, velocity and entropy) over the whole length , while the helical coiled tube length for all cases is shorter than the straight tube at the same conditions. The main parameters that affect the size of capillary tube and the behavior of refrigerant through it have been shown. The tube length increased with the increase of (condenser temperature, degree of sub-cooling and tube diameter) and decreased with the increase of mass flow rate and roughness. The helical tube length increased by increasing coil diameter and coil pitch . The results of the present study agree with the experimental data of previous works with error not exceeding ±10% .

Keywords : Adiabatic capillary tube, Household refrigerators, R134a, EES, Helical, Two-phase flow.

Two Dimensional Mathematical Model to Simulation Tigris River Upstream Third Bridge in Mosul City(Arbic)

Anas M. M. Rasheed; Dr. Nadira A. Mohammed

AL-Rafdain Engineering Journal (AREJ), Volume 21, Issue 1, Pages 7-19
DOI: 10.33899/rengj.2013.67341

Abstract:
The aim of this research is hydrodynamic analysis for Tigris river reach upstream the Third Bridge in Mosul city, and this reach have three islands changing the flow characteristics of Tigris river in the study area. Two dimensional mathematical model in SMS10.1 with geographical information system and satellite data are using to build the conceptual model for study area. The results showed that the efficiency of the mathematical model in analysis of Tigris river in the study area especially the results were presented by digital maps explain (water surface elevation, flow depth, shear stress, flow velocity, scour and deposition locations), in addition predications the shape of the Tigris river reach in the study area in the future.
Keywords: Tigris river, Simulation, Sediment transport, Flow analysis, SMS.

The Climatic Considerations for Planning & Architecture of the Traditional Arab City "Old City of Mosul,as aModel"(Arbic)

D.Turki Hassan; D.BahjatRashadShaheen

AL-Rafdain Engineering Journal (AREJ), Volume 21, Issue 1, Pages 19-32
DOI: 10.33899/rengj.2013.67342

Abstract
The cultural identity of any nation or country can't be confirmed unless the continuity with it's past. The architectural heritage is the most important links with the nation's history, which is formed through several centuries, through interaction with the local environment in all its dimensions, the local climatic condition is the most influential factor.
The research hypothesize that the role played by the climate is distinctive in the urban and architecture scales, In the light of that, the objective of the research is to study the relationship between urban-architectural forms and climate, and exploring the strategies adopted by the traditional city for the climatic adaptations and controlling its influence. The research selects the old city of Mosul as a case study because it has similar urban fabric found in the others traditional Arab cities, which have semi-dry or dry climates.

Mixed convection Flow Along a Horizontal Permeable Lpate in Porous Medium With Variable Permeability-Surface Temperature And Concentration (English)

Amir S. Dawood; Saddam A. Mohammad

AL-Rafdain Engineering Journal (AREJ), Volume 21, Issue 1, Pages 20-39
DOI: 10.33899/rengj.2013.67351

Abstract
The non-Darcy mixed convection from a horizontal permeable surface embedded in a saturated porous medium with the simultaneous heat and mass transfer has been studied. Uniform and variable permeability effects are also investigated. Variable surface temperature and concentration was considered as a surface condition. Nonsimilar governing equations are obtained by using a suitable transformation and solved numerically by a finite difference method. It is observed that for uniform permeability surface fluid suction and increasing the power law index, thermal dispersion parameter, and buoyancy ratio increases the heat and mass transfer rates. Surface fluid injection and increasing the inertia effect parameter have opposite effect. Increasing Lewis number decreases the heat transfer rate and increases the mass transfer rate. For any particular parameter, variable permeability enhances the heat and mass transfer rates.

Keywords: Porous medium, Mixed convection, Horizontal plate, Nonsimilarity solutions, Heat and mass transfer.

Theoretical Dimensions Of Digital Houses Architecture(Arbic)

Bayda H. Saffo; Niam B. Manona; Shatha Y. El - Sheikh

AL-Rafdain Engineering Journal (AREJ), Volume 21, Issue 1, Pages 33-56
DOI: 10.33899/rengj.2013.67344

Digital houses have formed an important subject , examined by several architectural studies , which have declared the special effects of the information technology revolution on houses design, especially,its form,function and construction , as well as , special effects on the human activities being practiced in.
This paper has discussed the importance of this subject and its theoretical knowledge , in order to determine the research problem , represented by the ambiguous knowledge in the different aspects of digital houses design , in order to explore design considerations in its design , thus its objective has determined by revealing this and its approach has presented by building up a theoretical framework includes two main aspects, the first includes variables concerning the digital house design , whereas the second , includes variables concerning human activities.
Conclusions have shown different design considerations which have been employed in digital houses designs of the international experiences, as well as determining the priorities of future design treatments .

Keywords: digital houses, information technology revolution, digital Architecture

Modeling of Heat Transfer from a Horizontal Tube Immersed in a Shallow Gas Fluidized Bed (English)

a Taha Hussin; Asma; Dr.burhan Mahmood Al-Ali

AL-Rafdain Engineering Journal (AREJ), Volume 21, Issue 1, Pages 40-55
DOI: 10.33899/rengj.2013.67352

Abstract
In this study, modeling of heat transfer from a horizontal tube immersed in a shallow gas fluidized bed was investigated. The Surface Particle Emulsion heat transfer model SPE and the single particle model were used in the present work as theoretical models to calculate the average heat transfer coefficient at the tube surface. On the basis of sectorizing the surface of the tube into the three sections (top, side and bottom), The SPE model was used for the top section of the tube and the single particle model was used for the side and bottom of the tube. The experimental work involved measuring particle residence time at the heat transfer surface by using a 30frame/sec digital camera, and the bubble frequency was used as a measuring tool for predicting the particle residence time at the transfer surface. The results obtained show that the average heat transfer coefficient increases with the decrease in particle diameter and the increase in the height of the tube above the distributor plate, while tube size has a small influence on average heat transfer coefficient. The calculated results obtained from the models agreed reasonably well with experimental data.

Efficiency of Dissimilar Friction Welded (Super Duplex Stainless Steel SAF 2507- Mild Steel) Joints (English)

Ramadhan H Gardi; Salm Aziz Kako

AL-Rafdain Engineering Journal (AREJ), Volume 21, Issue 1, Pages 56-65
DOI: 10.33899/rengj.2013.67353

Abstract
The aim of this research paper is to investigate the efficiency of dissimilar friction welded super duplex stainless steel SAF 2507 and mild steel joints. The joints were obtained using rotary friction welding process. Friction pressure and forging pressure are varied in three different cases but rotational speed and friction time are kept constant .The joints were subjected to tensile strength and metallographic study. The tensile strength of welded joints compared to that of SDSS SAF 2507 and mild steel in as received condition. The joint efficiency were calculated .The tensile strength and joints efficiency decreased with increasing friction pressure and forging pressure .The results attributed to change in mechanical, physical properties ,and micro structural changes of welded joints like change in ferrite to austenite percent, precipitation of carbides and nitrides ,sigma phase,….etc.
Key words: Friction welding, super duplex stainless steel, tensile strength

Effect of high temperature on Bond Strength in entrained air Reinforced Concrete(Arbic)

Dr. Abdul Hakeem Hamed Ahmed; Yaman Huthaifa Shaker

AL-Rafdain Engineering Journal (AREJ), Volume 21, Issue 1, Pages 57-67
DOI: 10.33899/rengj.2013.67345

Abstract
This research aims to study the effect of temperature on bond strength in air entrained concrete and to find the effect of adding entrained air on the properties of the fresh and hardened Concrete under the influence of high temperatures of different levels (20, 200, 400, 600 ºC). These properties are compared with those for normal concrete . In case of concrete structures exposed to an unexpected fire, changes are found in the properties of the concrete constituents, These changes are evaluated to assess the performance of these concrete structures and determine whether structures are safe or not .The research work includes an experimental study of the mechanical properties of the hardened concrete , and the effect of high temperature and entrained air admixture on concrete behavior including, compressive strength, splitting tensile strength, stress – strain relationship (modulus of elasticity) and bond strength between reinforcement and concrete. The work includes four different percentage of air entrained admixture (Sika_Aer) (0, 0.5, 1.0, 1.5 %) by weight of cement. The effect of these variables on the bond stress between concrete and reinforcement as a result of tensile forces using pullout test are investigated. The Results show that the failure for reinforced concrete bond strength depends on diameter of the steel bar used (Ø10 , Ø 12 and Ø 16 mm) , heating temperature for specimens after (28) days of water curing and also depends on the amount of admixture in concrete (Sika-Aer).

Keyword: Concrete, Bond Strength, Entrained air, High temperature

Comparison between MCML and CMOS Digital Circuits For Using ADS Simulation(English)

Dr.LuqmanSufer Ali; Zahra RafidMahmod

AL-Rafdain Engineering Journal (AREJ), Volume 21, Issue 1, Pages 66-76
DOI: 10.33899/rengj.2013.67354

Abstract:
In this paper, a comparison is done between MOS Current Mode Logic (MCML) and Complementary metal Oxide Semiconductor(CMOS) circuits operating in low power application. It is found that MCML logic circuits exhibit a decrease in delay and so decrease in overall power delayproductcompared with CMOS circuits. The tested inverter,D-latch NAND/AND, XOR/XNOR are optimized for low power and high-speed operation, according to the simulation of the circuits for lower voltage operating at data rate 2.5 GHz. This simulation is done using Advanced Design System(ADS2009).From the results shown it is seen that the MCML logic circuits reveal high efficiency and good performance at low power and high speeds which makes them to be more capable for application in the integrated circuits with high density.

Water Treatment of the Khosar in Mosul City By Using Alum and Activated Carbon(Arbic)

Soad Abid Abawee; Halla Nabeel Elea

AL-Rafdain Engineering Journal (AREJ), Volume 21, Issue 1, Pages 67-78
DOI: 10.33899/rengj.2013.67346

ABSTRACT
This study aimed at treating the water of Al-Khosar in Mosul City , by using the alum as a coagulant and then treat the supernatant by adsorption on the activated carbon . The optimum doses of alum were (10 , 15 , 20 ) mg/l . At ( 20 ) mg/l , the alum achieved highest removal of (COD , Nitrate , Turbidity , Cd , Cu ) , which were ( 33% , 32.6% , 99% , 71.2% , 85% ) respectively . Then the supernatant treated by adsorption on the activated carbon were achieved removal efficiency of pollutants mension above (46.6% , 71.4% , 87% , 44.4% , 25%) respectively.At (15) mg/l of alum , the alum achieved highest removal of ( pb , Hardness, Magnesium, Calcium, and Sodium) which were ( 68%, 33.7%, 19.6%, 16.6%, 36.8%) respectively. The activated carbon achieved removal efficiencies for the supernatant at (15)mg/l (33% , 16% , 15% , 18.1%, 31.8% ) respectively . Whereas (10) mg/l of alum achieved best removal for the (Zn ,Phosphate , Chloride) which were (66%, 41% , 22.5%) respectively . The supernatant adsorped on activated carbon achieved removal efficiency ( 54%, 60% , 35.4%) respectively . The treated water was low in Sodium and suitable for most plants , and the pH value is in the range , and the heavy metals concentrations were in the range of normal water .
Key Words : the Khosar , Coagulation , Alum , Adsorption , Activated Carbon , Heavy Metals .

Hardware Realization ofArtificialNeural Networks Using Analogue Devices(English)

Sh. H. Husain; A.I. Khuder

AL-Rafdain Engineering Journal (AREJ), Volume 21, Issue 1, Pages 77-87
DOI: 10.33899/rengj.2013.67355

Abstract
In this work the analogue neural network has been realized by electronic devices likeOperational Amplifiers and Field Effect Transistor (FET). The FET transistor has been utilized to self adjust weight function for neural network. By use of drain and source resistanceR_ds as function of applied voltage on the gate in linear characteristic region , this resistance has been connected to the input of Operational Amplifiers which becomes as weight function of neural network. Implementing these mentioned characteristics for both FET transistor and operational amplifier , the analogue neural network structure like neuron , weights function and activation function have been realized individually by using the National Instrumentmultisim 10 (NI) Software,then the analogue neural network has been trained successfully by using supervised learning rule like single layer perceptron learning rule and delta learning rule. The results, show good fulfillment of a neural network with analogue hardware devices and verifying the learning rules to train network.

Keywords:Analogue neural network, BP learning rule,Perceptron learning rule, NI circuit design suits software(NI multisim 10 software)

Static Unbalance Fault Diagnosis in Rotor Shaft Using Vibration Monitoring Technique(Arbic)

Ammar A. M. Al; Rawi; Professor Dr. Sabah M. J. Ali

AL-Rafdain Engineering Journal (AREJ), Volume 21, Issue 1, Pages 79-90
DOI: 10.33899/rengj.2013.67348

Abstract
Mechanical vibration is one of the most important phenomena studied by mechanical engineering, as well as other branches of engineering. Since most of the mechanical machines contain rotor shafts, then hard conditions during operation cause many faults to occur, one of which is the unbalance fault. Therefore, this research studies the diagnosis of static unbalance fault that causes the vibration of the rotor shafts, through conducting a real model for the unbalance fault of the rotor shaft in order to obtain the real vibration signal resulting from this fault. Moreover, monitoring the vibration signal in the frequency domain, and detecting the machine condition during operation at different speeds, and with position sensor device three axes for the bearing (horizontal, vertical, and axial). It has been proved that unbalance increases by increasing speed, and it becomes more obvious in the horizontal axis. Detecting faults unbalancing in the rotor shafts can also be done by taking the value of root mean square (RMS), which represents the maximum value that can be taken from the horizontal axis of the bearing. This value can be compared with the international standards (ISO 12372) to ensure being within the allowed limits.

Key: Vibration unbalancing, Static Unbalancing, Types Unbalancing,

Less Congested Open Shortest Path First Algorithm for Computer Networks(Arbic)

Dr. ManarYounisKashmola; ZenaNatiq Abdul-Kader

AL-Rafdain Engineering Journal (AREJ), Volume 21, Issue 1, Pages 91-101
DOI: 10.33899/rengj.2013.67349

Abstract
Open Shortest Path First (OSPF) is one of the most widely used intra-domain routing protocol. It is well known that OSPF protocol does not provide flexibility in terms of packet forwarding to achieve any network optimization objective. The common objective of network traffic engineering is to minimize the maximal link utilization in a network in order to accommodate more traffic and reduce the chance of congestion In this paper an algorithm, to solve congestion problem in an OSPF based best effort network, is proposed. This algorithm is called Less-congested Open Shortest Path First (LOSPF). A simple feed-forward neural network is used to predict the congestion problem in the computer network links which are over utilized. The neural network is trained to predict congested links based on a given traffic pattern. These predictions are used to modify Dijkstr's algorithm to select the shortest paths, that excluding those links.Better resource utilization is obtained by applying the resulting paths. This is achieved throughout avoiding congested links and using other links that are underutilized. Comparison between performance of the suggested algorithm and the performance of OSPF that uses Dijkstra's algorithm to find the shortest path. Simulation results show that LOSPFperformance is better in term of distributing links utilizations, and the queuing delay in the congested links.In spite of the superiority of the proposed LOSPFalgorithm, its execution time is almost same as that of the OSPF

Design and Implementation of a Network on Chip Using FPGA(English)

Dr. A. I. A. Jabbar; Noor .Th. AL Malah

AL-Rafdain Engineering Journal (AREJ), Volume 21, Issue 1, Pages 91-100
DOI: 10.33899/rengj.2013.67356

Abstract
The fundamental unit of building a Network on Chip is the router , it directs the packets according to a routing algorithm to the desired host. In this paper ,a router is designed using VHDL language and implemented on Spartan 3E FPGA with the help of Integrated software environment ( ISE10.1) . The utilization of the Spartan 3E resources is excellent ( for example the number of slices required doesn’t exceed 3%) .After that a (4×4) mesh topology network is designed and implemented using FPGA ( the number of slices is 43% of the available slices ) . An example is applied on the designed Network on Chip (NoC) which validates the design successfully .
Keywords: Router , SoC, NoC, VHDL, FPGA,VGA,MESH

Experimental Comparative Study on Composite RC T-Beams Behavior with Diverse Distributions of Headed Studs in Sagging –Moment Tensioned Concrete Media(English)

L. Kh. Al- Hadithy; M. R. M. Al-Alusi

AL-Rafdain Engineering Journal (AREJ), Volume 21, Issue 1, Pages 101-114
DOI: 10.33899/rengj.2013.67357

لغرض تقييم تأثير أعداد ونمط ترتيب روابط القص الوتدية ذوات الرؤوس في العتبات الخرسانية المسلحة بسيطة الارتكاز ذوات الوترات المصبوبة جزئيا والمرتبطة داخليا بحديد ساقية عند أسطحها السفلى ، تم تنفيذ منهاج تجريبي باستخدام ثلاث حالات من أعداد الأوتاد وتوزيعها إضافة إلى حالة السيطرة الخالية من الأوتاد .
لقد تبين إن حالة العتبة الحاوية على عدد معتدل من الأوتاد وغير متجانسة التوزيع بمسافات داخلية بين الأوتاد لا تقل عن عرض وترة العتبة تجمع المزايا الساندة للعتبتين الآخريتين اللتين تضمان أوتاد متجانسة التوزيع إحداهما غزيرة والأخرى متباعدة مع تحاشي عيوبها المحتملة . على وجه التحديد ، فان مجالات أفضلية العتبة المثلى هي : الجساءة والمطاوعة والمقاومة القصوى الإنثنائية ، إضافة إلى تقييد الانزلاق النسبي وخصائص الوحدة التمامية . رغم احتجاز الخرسانة في نطاق حديد الساقية ، فان انخفاضات حادة في مستويات مقاومة الانحناء القصوى والوحدة التمامية قد حصلت عند إزالة روابط القص .

Effect of Anisotropy on Unsaturated Hydraulic Conductivity and SWCC of Clayey Soil (English)

Dr. S. I. A. Khatta; M. N. J. Al-Zaidy

AL-Rafdain Engineering Journal (AREJ), Volume 21, Issue 1, Pages 115-133
DOI: 10.33899/rengj.2013.67358

Abstract
Infiltration of water in unsaturated soils has long been an interest of study in geotechnical engineering. A wide range in permeability coefficient has been proven to be a major obstacle in analyzing seepage problems. Soil-water characteristic curve (SWCC) is a fundamental constitutive relation for the explanation of the engineering behaviour of unsaturated soil. The effect of anisotropy on SWCC and unsaturated coefficients of permeability and diffusion has been studied in this paper, by taking sets of duplicate disturbed and undisturbed specimens prepared in the vertical, 45º inclined and horizontal directions. The results showed that there is a noticeably anisotropic in the basic characteristics of SWCC and the unsaturated coefficients of permeability and diffusion specially at the low values of suction. The variations of the hydraulic conductivity and vapor diffusivity versus suction gradient were opposite. Furthermore there is a noticeable difference between the disturbed and undisturbed specimens in the SWCC and coefficients of diffusion and permeability.
Key words: Anisotropy; directional variation; hydraulic conductivity; soil-water characteristic curve; unsaturated soil.

Finite Element Analysis of Strengthened Reinforced Concrete Beams (English)

Sura A. Majeed

AL-Rafdain Engineering Journal (AREJ), Volume 21, Issue 1, Pages 134-145
DOI: 10.33899/rengj.2013.67364

Abstract
This paper presentedthe application of nonlinear finite element models in the analysis of rectangular reinforced concrete beams strengthened with ferrocement in the form of U-jacket by using ANSYSsoftware. The numerical results are compared with thecorresponding experimental results of unstrengthened beams. The comparisons are carried out in terms of load- deflection curves at mid-span, and failure loads. The predicted results of reference beam are found to be in good agreement with the experimental results. Effect of number of layers of wire mesh on the strength of analyzed beams strengthened with ferrocement jackets has been studied. The same beam is also analyzed after strengtheing it with U-jacketsheets of Carbone Fiber reinforced Polymer (CFRB) and the predicted results are compared with that of the corresponding beams strengthened with ferrocement jackets. The strengthened beams have shown a remarkable improvement in their performances in terms of load deflection and ultimate load.The Carbone Fiber Polymer U-jacket greatly improved the beam ultimate failure load by about 37.44%.
Keywords:Beams, CFRP, Finite Element,Ferrocement,Strengthening.

The Implications of Modifying Traffic Circulation Down Town Amman CITY(English)

Wael H; Awad

AL-Rafdain Engineering Journal (AREJ), Volume 21, Issue 1, Pages 146-156
DOI: 10.33899/rengj.2013.67368

Abstract

Urban regeneration requires collaboration of traffic engineers with urban planners and architects to provide decision makers with quantitative assessment of the impact of attempted changes in the urban setting. Simulating traffic is a very powerful assessment tool for both traffic engineers and urban planners to help decision makers in selecting the best alternative solution based on predefined criteria while saving resources with high level of precision and accuracy. In this research paper, six action plans were suggested: provide better pedestrian facilities; provide better parking facilities; organize loading and unloading operations; relocate terminals and public transport routes; propose new circulation plan; and relocate the Police Station on Faisal Street. In accordance with all actions, an optimal traffic circulation scenario (new circulation plan) was compared to the do-nothing circulation scenario (current circulation plan). Macro and micro measures of effectiveness are used to quantitatively compare between the two scenarios. Results showed notable improvements in favor of the proposed new circulation plan; however traffic conditions are expected to significantly improve if the demand implications of adopting the other actions were considered.