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).
حل الاشكالية المنهجية في العلوم الانسانية المنهج البنيوي انموذجاً مقترحاً
The present research deals with studying the formal variations for the Quranic calligraphy at the beginning of Islam , as being regarded from the original Arabic calligraphies which were developed later till they became as they are now, where the calligraphers in pushing for simulating these original calligraphies and knowing the methods of their writing by the calligraphers at that time.That helped in enriching and developing the aesthetic and designing valuesFor these calligraphies, as being calligraphic achievements represent transmission resulted from the objective, aesthetic and indicative vision in producing the verses according to a certain form. This has a clear impact in tendency to the technical, aesthetic and expressing develo
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كَشفت التنقيبات في مدن العراق القديم كالوركاء وماري عـن بقايا أبنية المدارس الموسيقية ( ) . وفي العصر السومري الحديث ( 2000 – 1950 ق. م. ) حُفِظ ما يؤيد وجود مواد المنهج الموسيقي النظري والعملي لعملية التعليم في مدرسة المعبد أو القصر الملكي ، إضافة لبعض اللقى الآثارية كآلات فخارية خاصة بالطفل ، والتي بوساطتها كان يتم تعليم الطفل في البيت ( ) . واحتلت الموسيقى مكانة هامة في حضارات الشرق المختلفة المُتزامنة مع حضارات و
... Show MoreGraph is a tool that can be used to simplify and solve network problems. Domination is a typical network problem that graph theory is well suited for. A subset of nodes in any network is called dominating if every node is contained in this subset, or is connected to a node in it via an edge. Because of the importance of domination in different areas, variant types of domination have been introduced according to the purpose they are used for. In this paper, two domination parameters the first is the restrained and the second is secure domination have been chosn. The secure domination, and some types of restrained domination in one type of trees is called complete ary tree are determined.
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The history of nations & civilizations shaped with its intellectual and cultural heritage and accumulation of met through the stages and years
Abstract traditional acculturation is one of the significant phenomena which is used in the old and modern arabic poetry. Poets have found in this tradition and flourishing arena for acculturation and interaction to Express their thoughts and inspection
Since her early beginning in 1974 in her novel "Les armoires vides", Annie Ernaux writing about life in all its various aspects remained her main goal. This novel gave the earliest signals of what would happen later on in her literary career. Indeed, her works showed abilities of echoing reality, her sufferance and experiences via the use of simple and clear language. Add to this, her writings are to be viewed as an expression of deep felt journey, and a continuous search due to the consequent changes coming out of her identity.
We try here to give an answer to the question about writing as to whether being, to Ernaux herself, a need for the search about her social and feminist identity, or a pure literary work
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