In real conditions of structures, foundations like retaining walls, industrial machines and platforms in offshore areas are commonly subjected to eccentrically inclined loads. This type of loading significantly affects the overall stability of shallow foundations due to exposing the foundation into two components of loads (horizontal and vertical) and consequently reduces the bearing capacity.
Based on a numerical analysis performed using finite element software (Plaxis 3D Foundation), the behavior of model strip foundation rested on dry sand under the effect of eccentric inclined loads with different embedment ratios (D/B) ranging from (0-1) has been explored. The results display that, the bearing capacity of st
... Show Morewell log analysis is used to determine the rock properties like porosity, water saturation, and shale volume. Archie parameters in Archie equation, which sometimes considered constants greatly affect the determination of water saturation, also these parameters may be used to indicate whether the rocks are fractured or not so they should be determined. This research involves well logging analysis for Zubair formation in Luhais field which involves the determination of Archie parameters instead of using them as constant.
The log interpretation proved that the formation is hydrocarbon reservoir, as it could be concluded from Rwa (high values) and water saturation values (low values), the lithology of Zubair from cro
... Show MoreA three-dimensional coupled finite element analysis algorithm is developed to predict the behaviour of single piles in clay. Three dimensional 20-noded brick elements are used in the analyses carried out on three documented field studies. Each node carries four degrees of freedom, three being for displacements in the three perpendicular space dimensions while the fourth is allocated for pore water pressure. The behaviour of the material of the pile is idealized through a linear elastic constitutive relationship while that for the soil by the Modified Cam-Clay model both extended to cover three-dimensional characteristics. The load-displacement results from the developed algorithm on the three selected problems from literature show a very
... Show MoreAnnealing and normalizing treatment are one of the most important heat treatment for the steel and its alloys. In the present work a mathematical model has been used to simulate this process, this model taken in account the variation in the physical material properties and heat transfer coefficient for the surface of metal. A numerical scheme based on control finite volume method has been used. A computer program with C++ language was constricted to found the final solution of the numerical equations.The model was used to estimate the temperatures distribution and the hardness value at each point of the workpiece. Good agreement has been obtained when compared the result of the present model with other experimental published data.<
... Show MoreRecovery of copper from actual spent etchant cupric chloride solution used in manufacturing of printed circuit board (PCB) containing 124 g/l Cu+2 ions concentration and 60 g/l hydrochloric acid was investigated in a batch mode jacketed tank. This tank was constructed with inner dimensions of 19×10×15 cm3 . Cylindrical rode-shape titanium was used as cathode, while two rectangular shaped graphite were used as anodes. The parameters studied were: current density (0.16-0.30 A/cm2 ), copper concentration in etchant solution (30-124 g/l) and the temperature (25-45o C). The highest current efficiency obtained was about 92% and the lowest power consumption achieved was about 2.7 W.h/g within the temperature range 25-35o C.
Maximum power point tracking (MPPT) is used in photovoltaic (PV) systems to enhance efficiency and maximize the output power of PV module, regardless the variation of temperature, irradiation, and the electrical characteristics of the load. A new MPPT system has been presented in this research, consisting of a synchronous DC-DC step-down Buck converter controlled by an Arduino microcontroller based unit. The MPPT process with Perturb and Observe method is performed with a DC-DC converter circuit to overcome the problem of voltage mismatch between the PV modules and the loads. The proposing system has high efficiency, lower cost and can be easily modified to handle more energy sources. The test results indicate that the u
... Show MoreThe aim of the present work is to study the effect of different outlet nozzle diameters, by using one or two nozzles on the performance of divergent vortex tube and also to determine the effects of various parameters on the vortex tube cooling performance such as: refrigeration capacity, coefficient of performance, isentropic efficiency. The experimental investigation was carried out on a divergent vortex tube rig manufactured for the present study covering all tests. The effect of different outlet nozzle diameters ( dn= 4 mm, dn = 5 mm, and dn= 6.5 mm) on the performance of the vortex tube is described by using one nozzle or two nozzles by varying the pressure of the inlet air and cold air mass ratio (μc) within the ranges (Pi abs=2 -
... Show MoreThe potential to remove Pb(II) from aqueous solutions through biosorption using four raw dead plant biomasses (karab, bardie, rice hulls and corn-cobs) was investigated in batch tests and compared with that for the PAC. From tests, it was found that the four types of dead-plant biomasses had shown high removal efficiency with the descending order (karab, bardie, rice hulls and corn cobs). Their percent removal (% R) of Pb(II) were (98.76, 96.10, 95.16 and 94.70) respectively at pH 4 with 0.2 g of sorbent/100 ml of 10 ppm lead solution , while it was (99.8 %) for PAC. Generally through batch system at a laboratory scale, karab has proved to be an efficient biosorbent for the removal of Pb(II) from aqueous solutions with low initial ion co
... Show MoreIn this research, Artificial Neural Networks (ANNs) technique was applied in an attempt to predict the water levels and some of the water quality parameters at Tigris River in Wasit Government for five different sites. These predictions are useful in the planning, management, evaluation of the water resources in the area. Spatial data along a river system or area at different locations in a catchment area usually have missing measurements, hence an accurate prediction. model to fill these missing values is essential.
The selected sites for water quality data prediction were Sewera, Numania , Kut u/s, Kut d/s, Garaf observation sites. In these five sites models were built for prediction of the water level and water quality parameters.
Climate change causes water shortage (water scarcity) in addition to the dams built by neighboring countries, which caused a lack of Iraq's water share. Therefore, evaluating the irrigation system requires considering its suitability, adequacy, and efficiency. Irrigation is considered adequate when it maintains water availability within the root zone, and if the amount to be added is determined, irrigation efficiency becomes possible by avoiding water loss. Babil Governorate is considered one of the agricultural governorates in the country that depends on its irrigation from Shatt Al-Hilla. The study area is the Elaj project. Three fields were selected for the project (B1, B2, and B3). These fields are lo
... Show MoreIn this paper, a design of the broadband thin metamaterial absorber (MMA) is presented. Compared with the previously reported metamaterial absorbers, the proposed structure provides a wide bandwidth with a compatible overall size. The designed absorber consists of a combination of octagon disk and split octagon resonator to provide a wide bandwidth over the Ku and K bands' frequency range. Cheap FR-4 material is chosen to be a substate of the proposed absorber with 1.6 thicknesses and 6.5×6.5 overall unit cell size. CST Studio Suite was used for the simulation of the proposed absorber. The proposed absorber provides a wide absorption bandwidth of 14.4 GHz over a frequency range of 12.8-27.5 GHz with more than %90 absorp
... Show MoreTheoretical and experimental study has been conducted on developing laminar mixed convection heat transfer air flow through an annulus for both aiding and opposing flow with uniformly heated inner cylinder and adiabatic outer cylinder for the theoretical part and with uniformly heated inner cylinder while the outer cylinder is subjected to the ambient for the experimental part. In the theoretical investigation the energy equation was first solved using (ADI) method, and then the momentum equations and continuity equation were combined as the pressure correction formula and solved by the SIMPLE algorithm. The present theoretical work covers Ra range from 4.55*10 to 5.649 10° and Re range from 300 to 1000 with radius ratio of 0.555 and Pr
... Show MoreThe need for quick airborne transportation is critical, especially in emergencies. Drones with suspended payloads might be used to accomplish quick airborne transportation. Due to the environment or the drone's motion, the slung load may oscillate and lead the drone to fall. The altitude and attitude controls are the backbones of the drone's stability, and they must be adequately designed. Because of their symmetrical and simple structure, quadrotor helicopters are one of the most popular drone classes. In this work, a genetic algorithm with two weighted terms fitness function is used to adjust a Proportional-Integral-Derivative (PID) controller to compensate for the altitude and attitude controllers in a quadrotor drone
... Show MoreIn this paper, an experimental study was conducted to enhance the thermal performance of a double-pass solar air heater (SAH) using phase change material (PCM) for thermal storage at climatic conditions of Baghdad city - Iraq. The double-pass solar air heater integrated with thermal storage system was manufactured and tested to ensure that the air heating reserved after the absence of the sun. The rectangular cavity filled with paraffin wax was used as a latent heat storage and incorporated into the lower channel of solar air heater. Experiments were carried out to evaluate the charging and discharging characteristics of two similar designed solar air collectors with and without using phase change material at a constant
... Show MoreEntropy generation was studied for new type of heat exchanger (shell and double concentric tubes heat exchanger). Parameters of hot oil flow rate, temperature of inlet hot oil and pressure drop were investigated with the concept of entropy generation. The results showed that the value of entropy generation increased with increasing the flow rate of hot oil and when cold water flow rate was doubled from 20 to 40 l/min, these values were larger. On the other hand, entropy generation increased with increasing the hot oil inlet temperature at a certain flow rate of hot oil. Furthermore, at a certain hot oil inlet temperature, the entropy generation increased with the pressure drop at different hot oil inlet flow rates. Final
... Show MoreIn this paper the variable structure control theory is utilized to derive a discontinuous controller to the magnetic levitation system. The magnetic levitation system model is considered uncertain, which subjected to the uncertainty in system parameters, also it is open-loop unstable and strongly nonlinear. The proposed variable structure control to magnetic levitation system is proved, and the area of attraction is determined. Additionally, the chattering, which induced due to the discontinuity in control law, is attenuated by using a non-smooth approximate. With this approximation the resulted controller is a continuous variable structure controller with a determined steady state error according to the selected control
... Show MoreA numerical study of mixed convtion cooling of heat dissipating electronic component, located in a rectangular enclosure, and cooled by an external through flow of air is carried out.A conjugate problem is solved by primitive variables method, describing the flow and thermal fields in air .The interaction between the components is of interest here, depending on their relative placement in the enclosure, and different configuration are considered. for Re=100 laminar, steady flow is predicted for up to Gr/Re2 =25 according to heat source location in the enclosure. The mixed convection regime, where the buoyancy effects are comparable to the forced flow, occurs at values of Gr/Re2 between 0.01 and 25 .The results are of values in search for
... Show MoreThe present work reports a direct experimental comparison of the catalytic hydrodesulfurization of
thiophene over Co-Mo/Al2O3 in fixed- and fluidized-bed reactors under the same conditions. An
experimental pilot plant scale was constructed in the laboratories of chemical engineering department,
Baghdad University; fixed-bed unit (2.54 cm diameter, and 60cm length) and fluidized-bed unit (diameter of 2.54 cm and 40 cm long with a separation zone of 30 cm long and 12.7 cm diameter). The affecting
variables studied in the two systems were reaction temperature of (308 – 460) oC, Liquid hourly space
velocity of (2 – 5) hr-1, and catalyst particle size of (0.075-0.5) mm. It was found in both operations that the
conversion
Construction projects are complicated in nature and require many considerations in contractor selection. One of the complicated interactions is that between performance with the project size, and contractor financial status, and size of projects contracted. At the prequalification stage, the financial requirements restrict the contractors to meet minimum limits in financial criteria such as net worth, working capital and annual turnover, etc. In construction projects, however, there are cases when contractors meet these requirements but show low performance in practice. The model used in the study predicts the performance by training of a neural network. The data used in the study are 72 of the most recent roadw
... Show MoreABSTRACT
Critical buckling temperature of angle-ply laminated plate is developed using a higher-order displacement field. This displacement field used by Mantari et al based on a constant ‘‘m’’, which is determined to give results closest to the three dimensions elasticity (3-D) theory. Equations of motion based on higher-order theory angle ply plates are derived through Hamilton, s principle, and solved using Navier-type solution to obtain critical buckling temperature for simply supported laminated plates. Changing (α2/ α1) ratios, number of layers, aspect ratios, E1/E2 ratios for thick and thin plates and their effect on thermal
... Show MoreThe paper presents an investigation to the flutter speed of composite wing for different ply orientation. Structurally the composite wing was idealized as a composite beam load carrying structure. Theodorsen’s expression was used to get the 2- dimension unsteady lifting force and pitching moment in the limit of incompressible flow and subsonic speed which were integrated over the wing span. A free vibration analysis was first carried out to get the natural frequencies and mode shapes .The velocity-damping (V-g) method was used to calculate the flutter speed and the flutter frequency. A wing of unmanned aerial vehicle was manufactured from woven glass and polyester resin where the flutter speed was calculated experimentally by the wind
... Show Moreتقدم هذه الورقة تقييماً تقنياً واقتصادياً لنظام الطاقة المتجددة الهجين (HRES) في كلية الهندسة بجامعة بغداد. وتشمل الأهداف تحسين الموثوقية وتخفيف الطلب على الشبكة. تصميم نظام HRES مخصص ومتصل بالشبكة للجامعة، يتضمن الطاقة الشمسية الكهروضوئية ومولد الديزل. يتم تحديد التكوين الهجين الأمثل من خلال تقييم كامل للعوامل الاقتصادية والتقنية والبيئية باستخدام برنامج Homer-Pro. إلى جانب أنه يعالج التحديات الحاسمة في توفير ر
... Show MoreMarine ship hulls' corrosion resistance behavior under static and flowing conditions was investigated. The metal of the hull panels of marine ships was chemically and mechanically examined and analyzed, revealing that carbon steel type DIN 1.0501 C35 is employed in constructing the hull of ships in the port of Basrah in Iraq. A corrosion resistance test for this metal was carried out in laboratory-prepared seawater under static and flowing conditions at a flow rate of 1500 liter/hour and various immersion times (12, 24, 48, 120, 168, 336) hours. The temperature was kept constant at 30°C, and a fixed salt concentration of (3.5% sodium chloride). The corrosion rate of C35 carbon steel was calculated using the weight loss
... Show MoreIn the current study, the impacts of various curing states on some properties of reactive powder concrete (compressive strength, flexural strength, and dry bulk density) are being experimentally studied. The curing conditions include four different methods: immersion in normal water temperature (considered the reference curing state), immersion in warm water at 35ºC, immersion in boiling water, and curing with steam. For every combination, the water/binder ratio stayed unchanged at 0.2. Each reactive concrete mix was cast into three different configurations: 50mm only for cubes and 50×50×250 mm for prisms. Based on the improvement of RPC mechanical characteristics, the optimum curing method, as determined by the resul
... Show MoreThe contemporary ideas were characterized by the abundance and diversity of their knowledge, human and conceptual production, the strategy is both a general and a detailed framework covering all design disciplines both inside and outside the field of architecture. From here, many of these terraces emerged from fields outside the field of architecture, but soon moved to form an important nerve within the field of architecture. Hence the need to define a more comprehensive framework for studying one of the concepts that can frame the framework, namely the concept of "Alliteration", and its adoption as an architectural design strategy aimed at giving the resulting form a feature of rhetoric. So the research highlighted the
... Show MoreThe problem of rapid population growth is one of the main problems effecting countries of the world the reason for this the growth in different environment areas of life commercial, industrial, social, food and educational. Therefore, this study was conducted on the amount of potable water consumed using two models of the two satellite and aerial images of the Kadhimiya District-block 427 and Al-Shu,laa district-block 450 in Baghdad city for available years in the Secretariat of Baghdad (2005, 2011,2013,2015). Through the characteristics of geographic information systems, which revealed the spatial patterns of urban creep by determining the role and buildings to be created, which appear in the picture for the
... Show MoreThe local asphalt concrete fracture properties represented by the fracture energy, J-integral, and stress intensity factor are calculated from the results of the three point bending beam test made for pre notches beams specimens with deformation rate of 1.27 mm/min. The results revealed that the stress intensity factor has increased by more than 40% when decreasing the testing temperature 10˚C and increasing the notch depth from 5 to 30mm. The change of asphalt type and content have a limited effect of less than 6%.
Now-a-days the Flexible AC Transmission Systems (FACTS) technology is very effective in improving the power flow along the transmission lines and makes the power system more flexible and controllable. This paper deals with the most robust type of FACTS devices; it’s a Unified Power Flow Controller (UPFC). Many cases have been taken to study how the system behaves in the presence and absence of the UPFC under normal and contingency conditions. The UPFC is a device that can be used to improve the bus voltage, increasing the loadability of the line and reduce the active and reactive power losses in the transmission lines, through controlling the flow of real and reactive power. Both the magnitude and the phase angle of th
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Shear and compressional wave velocities, coupled with other petrophysical data, are vital in determining the dynamic modules magnitude in geomechanical studies and hydrocarbon reservoir characterization. But, due to field practices and high running cost, shear wave velocity may not available in all wells. In this paper, a statistical multivariate regression method is presented to predict the shear wave velocity for Khasib formation - Amara oil fields located in South- East of Iraq using well log compressional wave velocity, neutron porosity and density. The accuracy of the proposed correlation have been compared to other correlations. The results show that, the presented model provides accurate
... Show MoreTemperature inside the vehicle cabin is very important to provide comfortable conditions to the car passengers. Temperature inside the cabin will be increased, when the car is left or parked directly under the sunlight. Experimental studies were performed in Baghdad, Iraq (33.3 oN, 44.4 oE) to investigate the effects of solar radiation on car cabin components (dashboard, steering wheel, seat, and inside air). The test vehicle was oriented to face south to ensure maximum (thermal) sun load on the front windscreen. Six different parking conditions were investigated. A suggested car cover was examined experimentally. The measurements were recorded for clear sky summer days started at 8 A.M. till 5 P.M.
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