Electro-chemical Machining is significant process to remove metal with using anodic dissolution. Electro-chemical machining use to removed metal workpiece from (7025) aluminum alloy using Potassium chloride (KCl) solution .The tool used was made from copper. In this present the optimize processes input parameter use are( current, gap and electrolyte concentration) and surface roughness (Ra) as output .The experiments on electro-chemical machining with use current (30, 50, 70)A, gap (1.00, 1.25, 1.50) mm and electrolyte concentration (100, 200, 300) (g/L). The method (ANOVA) was used to limited the large influence factors affected on surface roughness and found the current was the large influence f
... Show MoreIn this work an experimental study is performed to evaluate the thermal performance
of locally made closed loop solar hot water system using a shell and helical coiled tube
heat exchanger as a storage tank. Several measurements are taken include inlet and outlet
temperatures of both collectors and supply water and temperature distribution within the
storage tank. This is beside the water flow rate in both collectors and load cycle. The
main parameters of the system are obtained.
Composite materials are widely used in the engineered assets as aerospace structures, marine and air navigation owing to their high strength/weight ratios. Detection and identification of damage in the composite structures are considered as an important part of monitoring and repairing of structural systems during the service to avoid instantaneous failure. Effective cost and reliability are essential during the process of detecting. The Lamb wave method is an effective and sensitive technique to tiny damage and can be applied for structural health monitoring using low energy sensors; it can provide good information about the condition of the structure during its operation by analyzing the propagation of the wave in the
... Show MoreThe degradation and mineralization of 4-chlorophenol (4-CP) by advanced oxidation processes (AOPs) was investigated in this work, using both of UV/H2O2 and photo-Fenton UV/H2O2/Fe+3 systems.The reaction was influenced by the input concentration of H2O2, the amount of the iron catalyst, the type of iron salt, the pH and the concentration of 4-CP. A colored solution of benzoquinon can be observed through the first 5 minutes of irradiation time for UV/H2O2 system when low concentration (0.01mol/L) of H2O2 was used. The colored solution of benzoquinon could also be observed through the first 5 minutes for the UV/H2O2/Fe+3 system at high
concentration (100ppm) of 4-CP. The results have shown that adding Fe+3 to the UV/H2O2 system enhanced
In this study, the effect of the combination of micro steel fibers and additives (calcium hydroxide and sodium carbonate) on the size of cracks formation and healing them were investigated. This study aims to apply the use of self-healing phenomenon to repair cracks and to enhance the service life of the concrete structures. Micro steel fibers straight type were used in this research with 0.2% and 0.4% by volume of concrete. A weight of 20 and 30 kg/m3 of Ca(OH)2 and 2 and 3 kg/m3 of Na2CO3 were used as a partial cement replacement. The results confirm that the concrete cracks were significantly self-healed up to 30 days re-curing. Cracks width up to 0.2 mm were comp
... Show Morein this study a proposed design for reinforced conerete barriers in industrial units is presented. The barriers are deemed to mitigate the hazards of internal explosions to protect the surroundings. The Technical Manual (TM5-1300) for fortified struetures recommends the use of lacing reinforcement barrier walls when the plastic rotation exceeds a specified limit. Such reinforcement is essential in shear design but it needs special skill and additional cost. To avoid using lacing reinforcement, walls of grillage system is proposed in this study to reduce the plastic rotation of pancls. The panels are designed to respond plastically, while the grillage members respond clastieally. This is advantageous from reeruiting point of view since on
... Show MoreThe research deals with the structures of the contemporary travelers' buildings in particular, and which is a functional complex installations where flexibility, technical and stereotypes play an important role as well as the human values These facilities must represent physiological and psychological comfort for travelers. TThose are facilities where architectural form plays a distinguished role in reversing the specialty and identity of the building. Hence the importance of the subject has been in forced, as a result for the need to study these facilities and to determine the impact and affects by the surrounding environment, to the extent of the urban, environmental, urban, social, and psychological levels. The importance of the resea
... Show MoreFriction stir spot welding (FSSW) is a relatively new welding process that may have significant advantages compared to the fusion processes as follows joining of conventionally non-fusion weldable alloys, reduced distortion and improved mechanical properties of weldable alloys joints due to the pure solidstate joining of metals. In this paper, a three-dimensional model based on finite element analysis is used to study the thermal history in the spot-welding of aluminum alloy 2024. The model take place the thermomechanical property on the process of the welded metals. The thermal history and the evolution results with numerical model at the measured point in the friction stirred spot weld have a good matching, then the prediction of the t
... Show MoreThe aim of this research work is to study the effect of stabilizing gypseous soil, which covers
vast areas in the middle, west and south parts of Iraq, using liquid asphalt on its strength properties
to be used as a base course layer replacing the traditional materials of coarse aggregate and broken
stones which are scarce at economical prices and hauling distances.
Gypseous soil brought from Al-Ramadi City, west of Iraq, with gypsum content of 66.65%,
medium curing cutback asphalt (MC-30), and hydrated lime are used in this study.
The conducted tests on untreated and treated gypseous soil with different percentages of medium
curing cutback asphalt (MC-30), water, and lime were: unconfined compression strength, and o
Mechanical degradation hampers the practical usage of polymers for turbulent drag reduction
application. Mechanical degradation refers to the chemical process in which the activation energy of
polymer chain scission is exceeded by mechanical action on the polymer chain, and bond rupture
occurs. When a water-soluble polymer and surfactant are mixed in water solution, the specific structures
(aggregates) are formed, in which polymer film is formed around micelle. In this work, Xanthan gum (XG) –
Sodium lauryl ether sulfate (SELS) complex formation and its effect on percentage viscosity reduction
(%VR) was studied. It was found that SELS surfactant reduced the mechanical degradation of XG much
more efficiently than th
In this study, a three-dimensional finite element analysis using ANSYS 12.1 program had been employed to simulate simply supported reinforced concrete (RC) T-beams with multiple web circular openings subjected to an impact loading. Three design parameters were considered, including size, location and number of the web openings. Twelve models of simply supported RC T-beams were subjected to one point of transient (impact) loading at mid span. Beams were simulated and analysis results were obtained in terms of mid span deflection-time histories and compared with the results of the solid reference one. The maximum mid span deflection is an important index for evaluating damage levels of the RC beams subjected to impact loading. Three experi
... Show MoreA program of laboratory testing is carried out to study the performance of laterally loaded piles embedded in soil, which contains cavities. The testing apparatus is manufactured for carrying out the tests and a simple technique was used to simulate the cavities.
The program of testing consists of five groups: Group One was carried out on pile embedded in soil without cavities. The Second and Third Groups are performed on pile embedded in soil contain single cavity located in front and in touch with pile face for the Second Group and in back and in touch with pile face for the Third one. Group Four is performed on pile with the existence of two cavities located in front and in touch with pile face. Group Five is performed on pile wi
As a result of the rising amount of ceramic waste generated by demolition operations and the breaking down of ceramic products during transmission and production processes, the need to get rid of this waste increased. In addition to the importance of preserving natural resources, the trend has begun to utilize these wastes as a partial alternative to aggregates. In this research, it was studied to replace (30%) of the volume of coarse aggregate with crushed ceramic, replacing 10% by weight of cement with local metakaolin and Carbon fibers were added with (1%) by weight of the cementitious material in order to produce pervious concrete in terms of sustainability. Compressive strength, splitting, and density tests were per
... Show MoreModern manufacturing enterprises are increasingly faced with fierce international competition and fluctuating market conditions. To gain flexibility from a functional manufacturing system and efficiency from mass production, group technology has emerged as an effective compromise between the two. Identification and grouping of parts, that share similar processes into cells, is the basic problem in the design of cellular manufacturing systems. The design of cellular manufacturing systems is a complex, multi- criteria and multi -step process which can have significant implication for the entire organization. The formation of machine cell and part families have a number of constraints such as number of cells, cell size, technological requir
... Show MoreIn this paper, a national grid-connected photovoltaic (PV) system is proposed. It extracts the maximum power point (MPP) using three-incremental-steps perturb and observe (TISP&O) maximum power point tracking (MPPT) method. It improves the classic P&O by using three incremental duty ratio (ΔD) instead of a single one in the conventional P and O MPPT method. Therefore, the system's performance is improved to a higher speed and less power fluctuation around the MPP. The Boost converter controls the MPPT and then is connected to a three-phase voltage source inverter (VSI). This type of inverter needs a high and constant input voltage. A second-order low pass (LC) filter is connected to the output of VSI to reduce t
... Show MoreThe distribution of chilled water flow rate in terminal unit is an important factor used to evaluate the performance of central air conditioning unit. A prototype of A/C unit has been made, which contains three terminal units with a complete set of accessories (3-way valve, 2-way valve, and sensors) to study the effect of the main parameters, such as total water flow rate and chilled water supply temperature with variable valve opening. In this work, 40 tests were carried out. These tests were in two groups, 20 test for 3-way valve case and 20 test for 2-way valve case. These tests were performed at three levels of valve opening, total water flow rate and water supply temperature according to the design matrices establis
... Show MoreSoft clays are generally characterized by low shear strength, low permeability and high compressibility. An effective method to accelerate consolidation of such soils is to use vertical drains along with vacuum preloading to encourage radial flow of water. In this research numerical modeling of prefabricated vertical drains with vacuum pressure was done to investigate the effect of using vertical drains together with vacuum pressure on the degree of saturation of fully and saturated-unsaturated soft soils. Laboratory experiments were conducted by using a specially-designed large consolidometer cell where a central drain was installed and vacuum pressure was applied. All tests were conducted
... Show Moreتعد العدالة في توزيع الخدمات مكانها من المتطلبات الرئيسة ضمن عمل المخطط الحضري و الإقليمي ، لذا فقد شغل بال هذه الفئة من الباحثين إيجاد أو الاعتماد على سبل عديدة تساعد في تحقيق هذا التوزيع المثاني المناطق الخدمة المختلفة في المدينة. و كان النظام المعلومات الجغرافية (GIS) دورا بارزا في تذليل العديد من صعوبات العمل التي يواجهها واضعو الخطط الحصرية و الاقليمية على حد سواء، وخصوصا فيما يتعلق بعمليات التوزيع المك
... Show MoreExperimental and numerical studies have been conducted for the effect of injected air bubbles on the heat transfer coefficient through the water flow in a vertical pipe under the influence of uniform heat flux. The investigated parameters were water flow rate of (10, 14 and 18) lit/min, air flow rate of (1.5, 3 and 4) lit/min for subjected heat fluxes of (27264, 36316 and 45398) W/m2. The energy, momentum and continuity equations were solved numerically to describe the motion of flow. Turbulence models k-ε was implemented. The mathematical model is using a CFD code Fluent (Ansys15). The water was used as continuous phase while the air was represented as dispersed. phase. The experimental work includes design, build and instrument a test
... Show MoreBased on the biological human models in defending human body against viruses, a new approach in designing the anti-virus system is introduced. This approach is called SDS( Self- Defence System). The principle of the SDS is that each executable program is responsible of defending itself against viral-attacks. In this system, each executable program is injected with basic anti-virus component which is called Self-Defence Routine. This routine, together with dedicated anti-virus loading program are used to construct the SDS which protects the computer system from virus invasion
Piezoelectric transducers have become increasingly popular in vibration control applications. They are used as sensors and as actuators in structural vibration control systems. They provide excellent actuation and sensing capabilities. In this paper, the term smart beam refers to a beam with a finite number of collocated piezoelectric actuator / sensor pairs. The proposed thin smart beam governing equation was derived by the same procedure that the Bernoulli-Euler equation derived but with some additional mathematical terms to be valid for describing the smart beam. The engineering control techniques were used to obtain the solution of the proposed differential equation for the simply supported beam where with some auxiliary equations an
... Show MoreIn this work, numerical method approach has been used to simulate the solidification parameters
of an eutectic aluminum-silicon alloy in chilled metallic mould with copper. The approach is based on
the solution of heat flow equations of the casting and mould. In addition, the latent heat is treated as a
boundary condition between the liquid and solid phase. The results showed that different behaviors of
solidification parameters are obtained along the casting. Furthermore, the simulation approach of
solidification parameters in conjunction with the microstructure indicated that it is possible, to a large
degree, giving a knowledge about the microstructural features for any alloy system.
The World witnessed over the past few decades a clear change in the urban existence map, where the number of cities' residents has increased and the cities geographic area expanded, also networks of roads and electric power stations were spread. This extraordinary events caused the drawing of a different identity to the world, race with itself in the field of energy and raw materials consumption. Therefore, the research issue individualizes in the lack of available knowledge concerning the subject of environment friendly ecological urban desiging and planning.So the research aims to define the environmentally friendly eco-city' structural elements and to clarify their most important planning and design foundations. To In
... Show MoreModal testing has become commonplace in many industries today as a research and development tool. In this capacity, it is used primarily during product prototype development and for vibration problem in general. Many types of structural or parts faults will cause changes in the measured dynamic response of a structure. These changes will, in turn, cause change in the structure's modal parameter. The purpose of the present work is to propose an improved damage detection and location based on the measurement of modal parameter (natural frequency and mode shape) before and after faults, which they have varying extents, for three different sizes of Aluminum casing plates. This local damage can be translated into or characterization as a redu
... Show MoreThis work provides an analysis of the thermal flow and behavior of the (load-free) refrigerator compartment. The main goal was to compare the thermal behavior inside the refrigerator cavity to the freezer door (home refrigerator) effect and install a fan on the freezer door while neglecting the heat transmitted by thermal radiation. Moreover, the velocity distribution, temperature, and velocity path lines are theoretically studied. This was observed without affecting the shelves inside the cabinet and the egg and butter places on the refrigerator door as they were removed and the aluminum door replaced with a glass door. This study aims to expand our knowledge about the temperature and flow fields of this refrigerator mo
... Show MorePermanent deformations (rutting) of asphalt pavements which appear in many roads in Iraq.
have caused a major impact on pavement performance by reducing the useful service life of
pavement and creating services hazards for highway users. Therefore, it is important to analyze and
investigate this type of distress.
The objectives of the present paper include; the analysis of the main contributory factors
influencing rutting, and development of statistical model for the prediction of permanent
deformation in paving materials. To achieved these objectives for the requirements of data collection. five types of gradation. (40-50) asphalt cement and different types of filler are used to prepare three hundred sixty asphalt conc
Over the past two decades, there has been an increased interest in a new class of computational intelligence systems known as Artificial Neural Networks (ANNs). In this work, (ANNs) technique was applied in an attempt to predict the turbidity at intake of Al-Wathba water treatment plant (WTP) in Baghdad. This prediction is useful in the planning, evaluation, management, and operation of such plants, which may produce water of better quality. The available records from (1991-2000) were used for predicting turbidity in Tigris River, based on monthly maximum values of the water quality parameters near intakes of the water treatment plants. Multi-layer perceptron trainings using the back-propagation algorithm were used in this work. The feas
... Show MoreThe current Iraqi standard specifications for roads and bridges allowed the prepared Job-Mix Formula for asphalt mixtures to witness some tolerances with regard to the following: coarse aggregate gradation by ± 6.0 %, fine aggregate gradation by ± 4.0 %, filler gradation by ± 2.0 %, asphalt cement content by ± 0.3 % and mixing temperature by ± 15 oC. The objective of this work is to evaluate the behavior of asphalt mixtures prepared by different aggregates gradations (12.5 mm nominal maximum size) that fabricated by several asphalt contents (40-50 grade) and various mixing temperature. All the tolerances specified in the specifications are taken into account, furthermore, the zones beyond these tolerances
... Show MoreThis research represents a practical attempt applied to calibrate and verify a hydraulic model for the Blue Nile River. The calibration procedures are performed using the observed data for a previous period and comparing them with the calibration results while verification requirements are achieved with the application of the observed data for another future period and comparing them with the verification results. The study objective covered a relationship of the river terrain with the distance between the assumed points of the dam failures along the river length. The computed model values and the observed data should conform to the theoretical analysis and the overall verification performance of the model by comparing i
... Show MoreTo decrease the dependency of producing high octane number gasoline on the catalytic processes in petroleum refineries and to increase the gasoline pool, the effect of adding a suggested formula of composite blending octane number enhancer to motor gasoline composed of a mixture of oxygenated materials (ethanol and ether) and aromatic materials (toluene and xylene) was investigated by design of experiments made by Mini Tab 15 statistical software. The original gasoline before addition of the octane number blending enhancer has a value of (79) research octane number (RON). The design of experiments which study the optimum volumetric percentages of the four variables, ethanol, toluene, and ether and xylene materials leads
... Show More