The present study explores numerically the energy storage and energy regeneration during Melting and Solidification processes in Phase Change Materials (PCM) used in Latent Heat Thermal Energy Storage (LHTES) systems. Transient two-dimensional (2-D) conduction heat transfer equations with phase change have been solved utilizing the Explicit Finite Difference Method (FDM) and Grid Generation technique. A Fortran computer program was built to solve the problem. The study included four different Paraffin's. The effects of container geometrical shape, which included cylindrical and square sections of the same volume and heat transfer area, the container volume or mass of PCM, variation of mass flow rate of heat transfer fluid (HTF), and temperatures difference between PCM and HTF were all investigated. Results showed that the PCMs in a cylindrical container melt and solidify quicker than the square container. The increase in mass flow rate and/or temperature difference decreases the time required for complete phase change. Paraffin's solidify quicker than they melt and store more energy than they release
In this research, that been focused on the most important economic benefits expected when applying the three standards of sustainability in construction projects (economic, environmental and social). Fuzzy AHP, a multi-decision decision-making technique for evaluating construction projects. Which when used we get the speed and accuracy in the results. Using this technique will reduce uncertainties decisions significantly (fuzzy environment), that found in most projects .The results of the data analysis showed that the economic standards take the greatest relative importance (60%) among the three sustainability standards. Therefore, the implementation of any standards need a cost so the economic benefit of any proje
... Show MoreThis study deals with the shallow alluvial aquifer situated beneath the urban area of kirkuk city. The ancient part of the city (Shorja) is affected by seepage from local agricultural areas causing relatively high heavy metals concentration in groundwater. The selection of polluted site depended on the highest TDS value (3856 mg/L) associated with the highest heavy metal concentrations (Pb, Ni, Co and Zn) in groundwater. This study focuses on the evaluation of natural attenuation effectivity for long-term protection of groundwater quality using realistic three-dimensional reactive-transport groundwater model. The requirements of 3-dimensional reactive transport model were obtained from field observation and laboratory works, in addition
... Show MoreThis study includes isolation, purification, and identification of algae from the canal around Baghdad university Al-jadriah. Four unialgal cultures were obtained. These algal cultures included 3 species of cyanophyta ( Nostoc carneum, Westillopesis prolifica, Chroococcus turgidus), 1 species of chlorophyta (Chlorella vulgaris) . Different plants belonging to different families were collected and extracted for their oils which were Ricinus communis and Sesamum indicum (seeds), Matricaria chamomilla (flowers) .However, antialgal activity of the extracted oils were evaluated the isolated algae with 7 concentrations (0.09, 0.3, 0.5, 1, 10, 20 , 30) % using the agar wells diffusion method. Results showed that R. communis oil was more effecti
... Show MoreA theoretical analysis of mixing in the secondary combustion chamber of ramjet is presented. Theoretical investigations were initiated to insight into the flow field of the mixing zone of the ramjet combustor and a computer program to calculate axisymmetric, reacting and inert flow was developed. The mathematical model of the mixing zone of ramjet comprises differential equations for: continuity, momentum, stagnation enthalpy, concentration, turbulence energy and its dissipation rate. The simultaneous solution of these equations by means of a finite-difference solution algorithm yields the values of the variable at all internal grid nodes.
The results showed that increasing air mass flow (0.32 to 0.64 kg/s) increases the development o
The electrochemical behavior of carbon steel in water sweetening station in Libya has been studied in the range of ( 293–333 oC) using weight loss technique. Measurements were carried out over a range of Reynolds number (5000 – 25000).An apparatus was designed for studying the corrosion process in the turbulent regime, which is of industrial significance. It was found that The corrosion rate of carbon steel in water sweetening station is under diffusion control and increases with increasing Reynolds number. On the other hand the variation of corrosion rate with temperature in the range of (293–333 oC) was found to follow Arrhenius equation and the activation energy approximately the same except at low Reynolds
... Show MoreThe present study deals with the assessment of water Quality Index to theAl-
Khadhimiya Groundwater city, by collection groundwater from 13wells during four
seasons, subjecting the samples to a comprehensive physicochemical analysis. The
13 parameters have been considered: pH, total hardness, calcium, magnesium,
turbidity, nitrate, electrical conductivity, total dissolved solid, Sulfate, Chloride,
zinc, manganic, and iron, that are used for calculating the WQI. From the result
shown, the most groundwater quality lies in Unfit for human drinking purpose. The
wells (1 and 11) and wells (3 and 10) were a bad water quality for drinking purpose
since they lie in poor and in very poor respectively according to the WQI.
The emergent bacterial resistance to antibiotics, most especially Carbapenems, has become a common phenomenon. The aim of the recent study was the observation and evaluation of the antibacterial susceptibility of Klebsiella pneumoniae in clinical specimens to different Carbapenems. One hundred isolates of K. pneumoniae isolated from different clinical sites, such as leg, caesarean section (CS), head, buttock, breast, thigh, and arm were tested. Using disc diffusion method, the isolates were tested for susceptibility to different antibiotics including Tobramycin, Ciprofloxacin, Aztreonam, Colistin sulphate, Ceftriaxone, Cefepime, Cefoxitin, Ceftazidime, Ertapenem, Meropenem, and Imipenem. The results were interpreted acc
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In this work, calculation of pressure losses in circulating system for two drilling muds is evaluated in Noor oil field. Two types of drilling muds that were used for drilling section 12 1/4" and 8 3/4" which are Salt saturated mud and Ferro Chrome Lignosulfonate-Chrome Lignite mud. These calculations are based on field data that were gathered from the drilling site of well Noor-15, which are included, rheological data, flow data and specification of drill string. Based on the obtained results, the best rheological model that fit their data is the Herschel-Bulkley model according to correlation coefficient value for their two drilling mud. Also, the difference between the calculated pressure lo
... Show MoreZinc Oxide is an indispensable substance in the field of dental treatment. It is used daily and intensively in all governmental and private dental clinics, leading to the disposal of very high concentrations of zinc with waste and eventually in landfill sites as a final destination for solid waste removal. This indicates the urgent need to investigate its behavior upon disposal due to the surrounding conditions. Approximately 4195 g of mixed dental waste samples were collected from (17) healthcare centers in Baghdad Al-Karkh. The leaching behavior of ZnO powder was investigated through batch reactors using makeup dental solid waste samples. The ZnO leaching was tested with 3 conditions; acidic, alkaline, and Ionic Streng
... Show MoreCharacterization is commonly known in stylistics to be the cognitive process in the readers' minds when comprehending a fictional character in a literary work .In one approach, it is assumed that characters are the outcome of the interaction between the words in the text on the one hand and the contents of our heads on the other. This paper is an attempt to understand how characterization is achieved by applying Culpeper’s (2001) model which seems to be to present a method of analysis that is more objective and more systematic in analyzing characters. Two characters are selected for discussion; Ralph and Jack from Golding’s (1954) Lord of the Flies. The novel talks about the corruption of human beings and the capacity of evil th
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