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).
Ibn Hajar is one of historian who had a role in historical writing represented by his writings in those active participation in the Arab-Islamic civilization, particularly his approach to intellectual, and pictures of us in his book that's part of the intellectual heritage, but a line that was a key part of the book, any manuscript
الحديث عن محمد بن إسحاق النديم حديث عن عالم جليل كان له فضل تصنيف سفر خالد من أسفار المعرفة و العلم و سجل ضم عناوين ما أنتجته الأمة العربية الإسلامية في وقت عزها و مجدها و سطوع كوكبها في سماء الدنيا ، فجاء هذا الكتاب جامعا نافعا في بابه .
GIS is characterized by great potentialeties to deal with huge geographical data and conclude what is necessary for it. It was very useful to get use of the potentialities of this system of GIS in the field of archaeology and to harvest very accurate results in a relatively short time, compared to the old archaeological methods.
عرض رسائل (الموقف من التعددية الحزبية في الفكر السياسي الاسلامي المعاصر)
نهضة الامة العربية والاسلامية في فكر مالك بن نبي
تعمل البنوك والمؤسسات المالية كوسيط مالي بين أصحاب المدخرات والودائع من جهة ومستخدمي هذه الأموال من جهة أخرى، وممارسة هذه الوساطة المالية بين الطرفين توضح العلاقة التي ينشأ عنها الائتمان، فالائتمان علاقة بين طرفين أولهما تزيد موارده على احتياجاته وهم (المدخرون) والثاني تزيد احتياجاته على موارده وهم (المقترضون)، وطبيعة العلاقة التي تنشأ بينهما تأخذ أحد شكلين: مباشر دون وساطة من أي طرف خارجي، أو غير مباشر عن
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The research explores the shapes preferred by children and the extent to which it can be utilized on the experimental kindergarten at the Woman’s School of Education. To achieve the goal, the researcher has displayed pictures that have been chosen from within the research boundaries which represent four categories: Geometrical shapes which included (squares, rectangles, triangles, and circles), agricultural shapes which included (apples, oranges, bananas, and grapes), motion pictures shapes (cartoon characters) which included (Jerry the mouse, Twitty the bird, Bugs Bunny the rabbit, and Winnie the pooh), and animal shapes which included (dogs, fishes, frogs, and horses) to the sample children of (60) child (boys and girls) that
... Show Moreتشكل سوق الاوراق المالية ركناً اساسياً من اركان هيكل النظام التمويلي في النظم الاقتصادية المعاصرة، لما تقوم به هذه الاسواق من دور مهم في حشد المدخرات المحلية وتوجيهها في قنوات استثمارية تعمل على دعم الاقتصاد القومي وتزيد من معدلات الرفاهية الاقتصادية لافراده، فضلاً عن كونها مرأة للوضع الاقتصادي العام في البلاد.
ونتيجة للروابط القوية بين سوق الاوراق المالية والاقتصاد، عُدّ استقرار ونمو
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After atour-For quite somtime,in the field of research and investingation on the economic aspects and the impact of her money is mportantin the evolution and emegece of the Islamic countres,especially including especially Morkhana him specimer nigh borhood the countries of the mashreq al islami,searhout,among other things summarilesas