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).
In the latest years there has been a profound evolution in computer science and technology, which incorporated several fields. Under this evolution, Content Base Image Retrieval (CBIR) is among the image processing field. There are several image retrieval methods that can easily extract feature as a result of the image retrieval methods’ progresses. To the researchers, finding resourceful image retrieval devices has therefore become an extensive area of concern. Image retrieval technique refers to a system used to search and retrieve images from digital images’ huge database. In this paper, the author focuses on recommendation of a fresh method for retrieving image. For multi presentation of image in Convolutional Neural Network (CNN),
... Show MoreThe poverty in the developing countries is output to under development as we consider welfare, where as when the poverty disappear that produced be the general development . Historically, in our countries, the underdevelopment is the result of colonialism period and what is associated with it of transferring the surplus abroad and the disorder of production structure. And at the present time, the poverty is reproduced and aggravated in the last years as a result of many internal and external reasons.Today, poverty is associated in many forms with the poverty previously.
المقدمة
أرادة الذات بين الأستلاب والأسترداد في قصيدة البياتي
The followers of philosophical lesson in Iraq discover steps and important stages through which the country had passed in , since the control of this thought in Arab Islamic civilization until recent time as well as touch the important changes that had happened on it
لم تكن المخدرات وليدة هذا العصر فقد عرفها الانسان منذ القدم وحاربتها المجتمعات القديمة ثقافياً واجتماعياً ودينياً ، حيث تعتبر المخدرات اخطر كارثة عرفتها البشرية في تاريخها وبدأت تتطور لتصبح تجارة عالمية غير مشروعة ترعاها عصابات منظمةهدفها تدمير طاقات وقدرات وقيم الشباب آمال هذه الامة وكنزها الحقيقي وهذا يعني تفريغ المجتمع من العقول المبدعة فيه حتى يبقى مجتمعنا متخلفاً من السهل السيطرة عليه.
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Interested in current research examining the concept of synthesis in contemporary ceramics, he studied the synthesis as a concept to achieve technical and aesthetic innovation.
The study comes in four axes. The first axis to ensure the general framework for research, containing the problem, which is to ask the following: Is the concept of synthesis role in enriching the contemporary ceramic done? The importance of research and study are needed in addition provide knowledge in the field of contemporary art
Iraqies has a spot in administration of the libraries and organized it since the reign of civilizations , the ancient libraries in the world were in the mesopatemia, then Baghdad had crown to be Islamic civilization when it hold the greatest ones as Bait Al-Hikma according to its organization as well as the persons who were responsilble for libraries must be of higher education and thoutful ones .
إن أهميـة بحثنـا تتضـح مـن خـلال التطـرق إلى دراسـة المـذهب العسـكري في حقبـة الاتحـاد السـوفيتي السـابق وإبـراز الجوانـب الرئيسـة المتعلقـة بفلسـفة المـذهب العسـكري السـوفيتي ومضـامينه الاستراتيجية مــن جانــب، وفلســفة المــذهب العســكري الروســي لمرحلــة مــا بعــد الحــرب البــاردة والتغـيرات المهمـة الـتي طـرأت عليـه، ممـا أفـرز لنـا بطبيعـة الحـال مضـامين مـذهب عسـكري روسـي جديــد قــد يتقــا
... Show Moreاشكالية الطائفية السياسية في العراق بين الاستمرارية والانكفائية