A numerical study of the two-dimensional steady free convection flow in an inclined annulus between two concentric square cavities filled with a porous medium is presented in this paper for the case when the side outer walls are kept with differentially heated temperature while the horizontal outer walls and the inner walls are insulated. The heated wall is assumed to have spatial sinusoidal temperature variation about a constant mean value. The Darcy model is used and the fluid is assumed to be a standard Boussinesq fluid. For the Cartesian coordinate system, the governing equations which were used in stream function form are discretized by using the finite difference method with successive under – relaxation method (SUR) and are solved by Gauss-Siedel iterative method. The upwind scheme was used for the transport terms in the energy conservation equation. The results are presented to demonstrate the streamlines, the isotherms, and the Nusselt number depending on the Rayleigh number ranging from (Ra =10 to 1000), dimension ratio from (Dr = 0.15 to 0.45), and the inclination angle from (= 0o to 45o). Also the effects of the amplitude (=0 to 1) and the wave number (f =0 to 5) of the heated side wall temperature variation on the free convection are investigated. The results show the effect of previous parameters (Ra, Dr,, , and f) on the flow fields and temperature profiles. It also show that the average Nusselt number is a strong function of the Rayleigh number, inclination angle, dimension ratio, and temperature variation. The peak value of the average Nusselt number based on the hot wall temperature is observed to occur at dimension ratio of (0.15), inclination angle of (40.1°), amplitude and wave number (1 & 0.75) for Rayleigh number of (1000).
This research is Interested in how the performance and implementation of factory production engine coolants of the General Company for Electrical Industries of its work, and to facilitate the flow of the decisions of senior management and access to all configurations, to ensure differentiation desired and reduce lost sales, resulting from poor scheduling of operations through the application of certain rules of scheduling operations in the production plant Engines Air-cooler, the objectives of research in identifying the best base and working to reduce the time and cost of Same Rules of Process which are considered the most influential of any organization and thr
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The subject of population support is one of the most important topics in the geography of the population as it shows the amount of burden on the workforce in society and reflects the balance or
Consistent with developments emerging environmental and canaccept by Iraq of the opportunities and challenges ahead in many fields,including economic areas, it requires the face of those developments andadaptation by adopting a lot of related concepts, including the concept ofcorporate governance and commitment to its principles, standards andmechanisms, especially those related to the formation of audit committeesand identify the tasks and duties entrusted to its members and terms oftheir independence as well as the rehabilitation of both scientific andpractical manner that is consistent with the interests of shareholders andother stakeholders in the companies, including banks, research sample, theresearch aims to shed light on the conc
... Show Moreنُفذت تجربة حقلية في أحد الحقول التي تقع على خط عرض 1333 59.93 شمالاً، وخط طول 37.913744" شرقاً، وعلى ارتفاع 31 م فوق مستوى سطح البحر خلال الموسم الخريفي لسنة 2018م لمعرفة تأثير نظم الحراثة المختلفة في إنتاجية الماء ونمو وحاصل الحنطة تحت التسوية الليزرية للارض ، استعملت في التجربة ثلاث معاملات المعاملة الأولى: الآت الحراثة وبمستويين هما المحراث المطرحي (T)، والمحراث الحفار (T2). إمَّا المعاملة الثانية نسبة انحدار تسوية سطح
... Show MoreThe present study is considered the first on this sector of the Tigris River after 2003. It is designed for two aims, the first is to demonstrate the seasonal variations in physicochemical parameters of Tharthar-Tigris Canal and Tigris River; the second is to explain the possible effects of canal on some environmental properties in the Tigris River. Water samples were being collected monthly. Six sampling sites were selected, two on Tharthar Canal and four along the Tigris River, one before the confluence as a control site and the others downstream the confluence with the canal. For a period from January to December 2020, nineteen physicochemical parameters were investigated including air and water temperature, turbidity, electrical cond
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يهدف البحث الى قياس مستوى ارتباط وتأثير القدرات المعرفية الدينامية في تنافسية الاعمال، وتكونت العينة من (155) فردا في اربعة مصانع للالبان في بغداد وهي (ابو غريب، والزراعة، والحلال، وعيون الرافدين) اذ تمثل مجتمع البحث من اصحاب المصانع، والمديرين والعاملين في السيطرة النوعية والبحث والتطوير والمهندسين والفنيين والعاملين ذوي الخبرة في صناعة الالبان. وجرى تحليل البيانات واختبار الفرضيات باستخدام الادوات الإحصا
... Show MoreFind aimed to reveal the teaching practices of the teaching faculties of education departments of the University of Baghdad in the light of the motives of learning from the perspective of students . Researcher selected the research community in a deliberate humanitarian sections of students and faculties of education for girls and IbnRushd . Ed reached basic research sample ( 400 ) students were numbers search tool questionnaire , and included (30) paragraph . In processors statistical data , use the weighted average and the weight percentile , results have shown that it is more paragraphs which received wide acceptance from the viewpoint of students ( do not make fun of the students' answers wrong but corrects and discussed with them )
... Show Moreاثر التواجد العسكري الامريكي على النظام السياسي في العراق