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Energy and Exergy Analysis on Modified Closed Wet Cooling Tower in Iraq
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The present study involves experimental analysis of the modified Closed Wet Cooling Tower (CWCT) based on first and second law of thermodynamics, to gain a deeper knowledge in this important field of engineering in Iraq. For this purpose, a prototype of CWCT optimized by added packing under a heat exchanger was designed, manufactured and tested for cooling capacity of 9 kW. Experiments are conducted to explore the effects of various operational and conformational parameters on the towers thermal performance. In the test section, spray water temperature and both dry bulb temperature and relative humidity of air measured at intermediate points of the heat exchanger and packing. Exergy of water and air were calculated by applying the exergy destruction method on the cooling tower. Experimental results showed a significant performance improvement when using packing on the CWCT. It can be observed that the thermal efficiency for the CWCT with packing under a heat exchanger and CWCT with packing above the heat exchanger are approximately 40% and 25% higher than that of the CWCT without packing respectively. As another part of the experiment results, it is indicated that the exergy destruction is directly proportional to air flow rate, cooling water flow rate, inlet cooling water flow rate and inlet Air Wet Bulb Temperature (AWBT) whereas, it is inversely proportional with spray water flow rate. In comparison with the cooling capacity of the tower, it was found that the exergy destruction approximately less than 20%. Exergy efficiency behavior is inversely proportional with the behavior of the exergy destruction. Empirical correlations are obtained to predict water film heat transfer coefficient and air-water mass transfer coefficient considering the influences of operational parameters.

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Publication Date
Wed Dec 13 2017
Journal Name
Al-khwarizmi Engineering Journal
Performance Enhancement of the South Baghdad Thermal Station
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Aim of the research is the study of improving the performance of the thermal station south Baghdad and the main reasons for reduced its efficiency. South Baghdad power planet comprises (6) steam turbine units and (18) gas turbine units .The gas turbine units are composed of two groups: the first group is made up of gas units (1,2), each of capacity (123) MW. The design efficiency of gas turbine units is 32%. The actual efficiency data of steam units is 18.3% instead of 45% which is the design efficiency. The main reason for efficiency reduction of gas units is the rejected thermal energy with the exhaust gases to atmosphere, that are (450-510) ℃.The bad type of fuel used (heavy) fuel. Another reason for the low efficiency and has a neg

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Publication Date
Wed Apr 12 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Optical Properties of Aluminum Doped CdO Thin Films Prepared by Vacuum Thermal Evaporation Technique
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   In this work, thin films of undoped and Al-doped CdO with (0.5, 1 and 2) wt.%  were prepared by using thermal vacuum evaporation on glass substrate at room  temperature. The optical absorption coefficient (α) of the films was determined from transmittance spectra in the range of wavelength (400-1100) nm. The spectral transmission and the optical energy band gap decrease from 75% and 2.24 eV to 20%  and 2.1 eV respectively depending upon the Al content in the films, also our studies include the calculation of  the optical constants (refractive index, extinction coefficient, real and imaginary part of dielectric constant) as a function of photon energy.  It is evaluated that the optical band gap of

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Publication Date
Thu Mar 01 2018
Journal Name
Journal Of Engineering
Numerical Simulation of Thermal-Hydrodynamic Behavior within Solar Air Collector
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Solar collectors, in general, are utilized to convert the solar energy into heat energy, where it is employed to generate electricity. The non-concentrating solar collector with a circular shape was adopted in the present study. Ambient air is heated under a translucent roof where buoyant air is drawn from outside periphery towards the collector center (tower base). The present study is aimed to predict and visualize the thermal-hydrodynamic behavior for airflow under inclined roof of the solar air collector, SAC. Three-dimensional of the SAC model using the re-normalization group, RNG, k−ε turbulence viscus model is simulated. The simulation was carried out by using ANSYS-FLUENT 14.5. The simulation

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Publication Date
Wed Jul 01 2020
Journal Name
Journal Of Engineering
Examining sensitivity of financial performance at construction projects prequalification stage
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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

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Publication Date
Sat Aug 01 2015
Journal Name
Journal Of Engineering
Mechanical Properties of High Performance Concrete Containing Waste Plastic as Aggregate
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         The world's population growth and the increasing demand for new infrastructure facilities and buildings , present us with the vision of a higher resources consumption, specially in the form of more durable concrete such as High Performance Concrete (HPC) . Moreover , the growth of the world pollution by plastic waste has been tremendous. The aim of this research is to investigate the change in mechanical properties of HPC with added waste plastics in concrete. For this purpose 2.5%, 5% and 7.5% in volume of natural fine aggregate in the HPC mixes were replaced by an equal volume of Polyethylene Terephthalate (PET) waste , got by shredded PET bottles. The mechanical propert

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Publication Date
Tue May 23 2023
Journal Name
Journal Of Engineering
Serviceability Performance of Externally Prestressed Steel-Concrete Composite Girders
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The behavior of externally prestressed composite beams under short term loading has been studied. A computer program developed originally by Oukaili to evaluate curvature is modified to evaluate the deflection of prestressed composite beam under flexural load. The analysis model based on the deformation compatibility of entire structure that allows to determine the full history of strain and stress distribution along cross section depth, deflection and stress increment in the external tendons .
The evaluation of curvatures for the composite beam involves iterations for computing the strains vectors at each node at any loading stage. The stress increment determined using equations depended on the member deflection at points of connecti

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Publication Date
Fri Jun 01 2018
Journal Name
International Journal Of Civil Engineering And Technology (ijciet)
Performance assessment of biological treatment of sequencing batch reactor using artificial neural network technique.
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Artificial Neural Network (ANN) model's application is widely increased for wastewater treatment plant (WWTP) variables prediction and forecasting which can enable the operators to take appropriate action and maintaining the norms. It is much easier modeling tool for dealing with complex nature WWTP modeling comparing with other traditional mathematical models. ANN technique significance has been considered at present study for the prediction of sequencing batch reactor (SBR) performance based on effluent's (BOD5/COD) ratio after collecting the required historical daily SBR data for two years operation (2015-2016) from Baghdad Mayoralty and Al-Rustamiya WWTP office, Iraq. The prediction was gotten by the application of a feed-forwa

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Publication Date
Wed Mar 01 2023
Journal Name
Baghdad Science Journal
New Structures of Continuous Functions
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         Continuous functions are novel concepts in topology. Many topologists contributed to the theory of continuous functions in topology. The present authors continued the study on continuous functions by utilizing the concept of gpα-closed sets in topology and introduced the concepts of weakly, subweakly and almost continuous functions. Further, the properties of these functions are established.

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Publication Date
Thu Jan 06 2022
Journal Name
Al-adab Journal
اتجاهات العمود السياسي في جريدة الزمان الدولية ازاء الشأن العراقي دراسة تحليلية لعمود (توقيع) انموذجا للمدة من 1/12/2004 ولغاية1/2/2005
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ءأرﻘﻟا ةﺎﯾﺣﺑ ًﺎﻘﯾﺛو ًﻻﺎﺻﺗا لﺻﺗﺗ. نﻣ ﮫﺑﺗﺎﮐﻟﻟ ﻲﺻﺧﺷﻟا ﻊﺑﺎطﻟا ﻲﻔﺣﺻﻟا دوﻣﻌﻟا لﻣﺣﯾ ا فﻟﺗﺧﻣﻟ ﮫﻟوﺎﻧﺗ لﻼﺧ وا ﮫﺋارا وا هرظﻧ ﺔﮭﺟو لﻣﺣﺗ ﻲﺗﻟا ﺔﯾﻣوﯾﻟا ثادﺣﻻاو ﺎﯾﺎﺿﻘﻟ ﺢﺿﻔﺑ موﻘﯾو ثادﺣﻻاو ﺔﯾﺑﻟﺳﻟا رھاوظﻟﻟ ىدﺻﺗﯾ وا، ءيرﺎﻘﻟا ﯽﻟا ﮫﺑرﺎﺟﺗ وا هرﺎﮐﻓا ءﺎطﺧﻻا دﺻرﯾ بﯾﻗرﺑ ﮫﺑﺷا وھو، ءيرﺟﻟا دﻘﻧﻟا نﻋ مﻧﯾ بوﻟﺳﺎﺑ ﺔﺋطﺎﺧﻟا تﺎﺳرﺎﻣﻣﻟا ﺎﮭﺣدﻣﯾو تﺎﯾﺑﺎﺟﯾﻻا ﯽﻟﻋ

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Publication Date
Mon Dec 26 2022
Journal Name
Arab Science Heritage Journal
الخلفية التاريخية النسبية والمذهبية لبني يفرن واماكن وجودهم في المغرب والاندلس من الفتح الاسلامي الى القرن الخامس الهجري/الحادي عشر الميلادي دراسة تاريخية
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    The Berber tribes in the Islamic Maghreb and Andalusia had a distinct role in the future of states and entities .The Islamic Maghreb in terms of its stability,downfall,political relations and conflicts among them.Among these tribes was the Banu Yafran tribe, which is the subject of the study.

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