The effects of T-shaped fins on the improvement of phase change materials (PCM) melting are numerically investigated in vertical triple-tube storage containment. The PCM is held in the middle pipe of a triple-pipe heat exchanger while the heat transfer fluid flows through the internal and external pipes. The dimension effects of the T-shaped fins on the melting process of the PCM are investigated to determine the optimum case. Results indicate that while using T-shaped fins improves the melting performance of the PCM, the improvement potential is mainly governed by the fin’s body rather than the head. Hence, the proposed T-shaped fin did not noticeably improve melting at the bottom of the PCM domain; additionally, a flat fin is added to the optimal case (Added-Fin case) and compared to the No-Fin, Uniform-Fin, and Optimum T-shaped Fin cases (no added fin). The analysis shows that the total heat storage rate of the Added-Fin case increased by 141.7%, 58.8%, and 47.6% compared with the No-Fin, Uniform-Fin, and the Optimum T-shaped Fin cases, respectively. Furthermore, the total melting time for the Added-Fin case was 1882 s and decreased by 59.6%, 38.4%, and 33.6% compared with those of the No-Fin, Uniform-Fin, and the Optimum T-shaped Fin (Optimum) cases, respectively.
At the beginning of the nineties increased responsibility of the auditor to the community as the demand for auditing the environmental performance for the economic units in addition to audit the financial performance. With the aim of preserving the environment and reducing the damagse as aresult of the negative effects of the activities of these units.
The researh deal with two sides the first one identifies the theoretical framework of the concept of environmental audits, requirements, methods, types of procedures, and duties of the auditor in conducting environmental audits. It also deals with the concept of the enviro
... Show MoreThe aims of research is to identify the role of strategic human resource management Practices in organizational performance improvement in the Baghdad soft drinks company, as well as the implications of the results for both managers and practitioners.
In order to achieve the objectives of the research, the researcher designed questionnaire included (40) items to collect the initial data from the research sample consisting of (53) Single. In light of that has been collecting and analyzing data and test hypotheses using the statistical package for Social Sciences (SPSS21), and use a number of statistical methods to achieve the goal of the research, including the means, standard deviations and simple correla
... Show MoreObjectives: The demand for orthodontic treatment is nowadays increasing significantly for aesthetic improvement and to correct various kinds of malocclusion, yet the prolonged treatment time remains the main obstacle. This review aimed to demonstrate various orthodontic techniques and highlight the evidence-based successful approaches used for acceleration of orthodontic tooth movement. Materials and Methods: Data and sources of information pertaining to accelerated orthodontic tooth movement premised on English-written articles were searched using electronic databases including Google Scholar, Scopus, PubMed and MEDLINE. Results: This review demonstrated the availability of different surgical and non-surgical methods to enhance tooth movem
... Show MoreA novel design and implementation of a cognitive methodology for the on-line auto-tuning robust PID controller in a real heating system is presented in this paper. The aim of the proposed work is to construct a cognitive control methodology that gives optimal control signal to the heating system, which achieve the following objectives: fast and precise search efficiency in finding the on- line optimal PID controller parameters in order to find the optimal output temperature response for the heating system. The cognitive methodology (CM) consists of three engines: breeding engine based Routh-Hurwitz criterion stability, search engine based particle
swarm optimization (PSO) and aggregation knowledge engine based cultural algorithm (CA)
Dairy wastewater generally contains fats, lactose, whey proteins, and nutrients. Casein precipitation causes the effluent to decompose into a dark, strong-smelling sludge. Fluid waste contains soluble organic matter, suspended solids, and gaseous organic matter, which cause undesirable taste and smell, grant tone and turbidity, and advance eutrophication, which plays an essential role in increasing biological oxygen demand (BOD) in water. It also contains detergents and disinfecting agents from the rinses and washing processes, which increase the need for chemical oxygen (COD). One of the characteristics of dairy effluents is their relatively high temperature, high organic contents, and wide pH range, so the discharge of wastewater into
... Show MoreOilwell cementing operations are crucial for drilling and completion, preserving the well's productive life. However, weak and permeable formations pose a high risk of cement slurry loss, leading to failure. Lightweight cement, like foamed cement, is used to avoid these difficulties. This study is focused on creating a range of foamed slurry densities and examining the effect of gas concentration on their rheological properties. The foaming agent and foam stabilizer are tested, and the optimal concentration is determined to be 2% and 0.12%, respectively, by the weight of the cement.
Furthermore, the construction of samples of foam cement with different densities (0.8, 1.0, 1.2, 1.4, and 1.6) g/cc is performed to f
... Show Moreإنّ التّأمّل في الدّراسات الأدبيّة النّقديّة الحديثة الّتي تنظر إلى النّصّ أنّه لوحة تتشكّل من مجموعة تداخلات نصّيّة سابقة للنصّ المُنتج أو مُعاصرة له، تدفع القارئ إلى الغوص في أعماق النّصوص وتحليلها والكشف عن الآليّات والإجراءات الّتي اعتمدت في إنتاجه، وإظهار الجماليّات الفنّيّة التي شكلت في مُجملها كائنا حيّا يُعبّر عن حالات إنسانيّة مُستمرة الحدوث رغم تقادم الأزمان.
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... Show MoreMoney laundering is consider a crime in legal perspective and aphenomenon of negative effects in economic and Social perspective for thevarious countries of the world by the diversity of their economies to make thebadly damaged in the banking service and its reputation in some cases may leadto bankruptcy of banks, and the fact that banks is one of the most importantcircles that revolve the illicit funds, Due to its branched the banking operations,speed and overlap and increase it's complicated with the progress of bankingoperations and the use of electronic services modern here's challenges atvarious levels between the application of the legislation to combat moneylaundering and between actual fact it must find ways and means of legislat
... Show MoreA new Schiff base ligand Bis-1,4-di[N-3-(2-hydroxy-1-amino)- acetophenonylidene] benzylidene [L] and its complexes with (Mn(II) ,Co(II) ,Ni(II and Cu(II)) were synthesized . The ligand was prepared in two steps. In the first step a solution of (terphthalaldehyde) in methanol reacts under reflux with (p-aminoacetophenone) to give an intermediate compound [1-[3-({4-[(3-Acetyl-phenylimino)-methyl]-benzylidene}-amino)-phenyl]- ethanone which reacts in the second step with (2-Amino-phenol) giving the mentioned ligand. The complexes were synthesized by addition the corresponding metal salt solution to the solution of the ligand in methanol under reflux in (1:1) metal to ligand ratio. On the basis of, molar conductance, I.R., UV-Vis, HPLC, chlorid
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