Natural convection in a trapezoidal enclosure with partial heating from below and symmetrical cooling from the sides has been investigated numerically. The heating is simulated by a centrally located heat source on the bottom wall, and four different values of the dimensionless heat source length, 1/5, 2/5, 3/5, 4/5 are considered. The laminar flow field is analyzed numerically by solving the steady, two-dimensional incompressible Navier-Stokes and energy equations. The Cartesian velocity components and pressure on a collocated (non-staggered) grid are used as dependent variables in the momentum equations discretized by finite volume method; body fitted coordinates are used to represent the trapezoidal enclosure, and grid generation technique based on elliptic partial differential equations is employed. SIMPLE algorithm is used to adjust the velocity field to satisfy the conservation of mass. The range of Rayleigh number is (103≤ Ra ≤105) and Prandtl number is 0.7. The results show that the average Nusselt number increases with the increases of the source length.
English ابحث عن مقالات و مجلات ... تحليل علاقة ثقافة المنظمة بلازمة من منظور الفردبة - الجماعية أ.د زكـريا مطلك الدوري، أ.د سـعـد علي العـنزي، أ. يعرب عدنان السعيدي مجلة كلية بغداد للعلوم الاقتصادية الجامعة 2009, المجلد 2, العدد 20, الصفحات 107-122 الخلاصة تتعدد وجهات النظر بشأن الاسباب والمعالجات الممكنة للازمات، وان هذا الاختلاف يرجع بالاصل إلى تنوع المداخل التي يعتمد عليها الباحثين في تناول الظاهرة أو الموضوع. وضمن هذا
... Show MoreIn this paper, the Azzallini’s method used to find a weighted distribution derived from the standard Pareto distribution of type I (SPDTI) by inserting the shape parameter (θ) resulting from the above method to cover the period (0, 1] which was neglected by the standard distribution. Thus, the proposed distribution is a modification to the Pareto distribution of the first type, where the probability of the random variable lies within the period The properties of the modified weighted Pareto distribution of the type I (MWPDTI) as the probability density function ,cumulative distribution function, Reliability function , Moment and the hazard function are found. The behaviour of probability density function for MWPDTI distrib
... Show MoreThe purpose of this preliminary study is to verify the possibility of using Iraqi Zahdi date palm biomass as a resource for biogas production, methane in particular using thermophilic anaerobic digestion with waste water treatment activated sludge. Moreover, is to investigate the influence of extra nutrients addition to the digestion mixture. Biogas was captured in sealed jars with remote sensing modules connected to computer with integrated program to record the gas pressure continuously. A total gas pressure with 67% Methane was produced from date pulp waste fermentation with a yield of 0.57 Lit for each gram volatile solid of substrate. Addition of 1% yeast extract solution as nutrient increased Methane yield in liters by 5.9%. This i
... Show Moreهدف الدراسة معرفة التأثير السمي التراكمي للأعلاف الملوثة بالحنطة المتفحمة على أفراخ فروج اللحم .اجري هذا البحث في مختبرات الصحة الحيوانية التابعة لوزارة العلوم والتكنولوجيا استعمل 78 فرخاً لهذه التجربة قسمت إلى ستة مجاميع ربيت في أقفاص خاصة أعدت لهذا الغرض. تم تغذيتها يوميا على أعلاف ملوثة حسب برامج التغذية المتبعة , تمثلت المجموعة الأولى بمجموعة السيطرة والتي غذيت على عليقه تحوي الحنطة
In this research work, a new type of concrete based on sulfur-melamine modification was introduced, and its various properties were studied. This new type of concrete was prepared based on the sulfur-melamine modification and various ingredients. The new sulfur-melamine modifier was fabricated, and its fabrication was confirmed by IR spectroscopy and TG analysis. The surface morphology resulted from this modifier was studied by SEM and EDS analysis. The components ratios in concrete, chemical and physical characteristics resulted from sulfur-melamine modifier, chemical and corrosion resistance of concrete, stability of concrete against water adsorption, stability of concrete against freezing, physical and mechanical properties and durabi
... Show MoreIslamic civilization derived its religious law from Quran and sunnah which took care of human as a benefit person in life and how it treat with it , and because the civilization takes care of human , it would take also in his health , manners ,body and this is the aim of Islamic civilization ,all religious emphasize on Islamic laws and on helping poor people or weakness one.
The research aims to outline a governmental and societal communicative vision grounded in the principles of sustainable development within Iraqi governmental institutions. This is achieved by public relations practitioners incorporating these concepts and enhancing public awareness of them. Iraqi governmental institutions cannot deviate from the international pattern and societal mood that encompass the goals of sustainable development. The growing international and local interest in environmental issues has influenced governmental stances and actions towards the public.
The research's main problem revolves around addressing a pivotal question: What are the levels of empowerment of public relations practition
Being the meeting points of the world different languages and out of a scholarly perspective, comparative literature represents a cultural leap as well as an artistic and intellectual development or a global literary movement of both prose and poetry. Such homogenous literary structure requires a systematic and coherent study of the literary output of the people different cultures and civilizations. It also represents the theoretical approach of the present study that debates a systematic comparison between Ghassan Kanafani’s All That's Left to You and William Faulkner’s. The Sound and the Fury. Within the perspective of the descriptive analysis approach, the present paper discusses th
... Show MoreThe bank risks has greaten and changed in its nature under the developments of financial liberalization, banking innovation and increasing use for new financial instruments which created by the huge technological advancement happened in the banking industry. So that, banks in large choose to base the profitability measures adjusted for risks; that is we introduced this research. The most important reason led us to do this is the restriction to use the modern statistical methods by trade bank in Arab countries equally with world banks which were the antecedent to base those models. Therefore, the research problem is embedded in the banks need to use measures that link between profitability and risks and this is what achieved by RARC
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