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).
Tremendous efforts have been exerted to understand first language acquisition to facilitate second language learning. The problem lies in the difficulty of mastering English language and adapting a theory that helps in overcoming the difficulties facing students. This study aims to apply Thomasello's theory of language mastery through usage. It assumes that adults can learn faster than children and can learn the language separately, and far from academic education. Tomasello (2003) studied the stages of language acquisition for children, and developed his theory accordingly. Some studies, such as: (Ghalebi and Sadighi, 2015, Arvidsson, 2019; Munoz, 2019; Verspoor and Hong, 2013) used this theory when examining language acquisition. Thus,
... Show More
لكل دولة في هذا العالم خطابها السياسي والذي يحدد سياستها الداخلية والخارجية، وهي سياسة ثابتة تنطلق من مفاهيم وبرامج وثوابت تخدم مصالحها الحيوية، لكون الخطاب السياسي ليس مجرد كلام عابر في عالم السياسة الدولية وانما هو ثوابت مهمة يحدد توجهات هذه الدولة او تلك ويحدد دورها الدولي وطبيعة العلاقة مع البلدان الاخرى ومنها الدول المجاورة لها. شهد العراق بعد العام 2003 تحديات جديدة تمثلت بتغليب خطابات الطائفية والكراه
... Show Moreفاعلية تطبيق اسلوب المهام الدراسية في اتقان اللغة الاسبانية للطلبة العراقيين.
the boot of honesty in the dictionary the term linguistic and religious
heritage, literary and Islamic Sufi thought, and concept in the literature of Imam
Ali, peace is upon him. And studied the summary first concerns its presence in the
literature and implications and directions, either the second part, has cared for the
analytical study has found research that safe weight was the counterpart of the
personality of the Imam accompanied the character most prominent in his
character, namely, (courage), it has struggled to deliver a impact of humanity in his
time and after the word and deed, It was based on the imagination in the formation
of images sensual and intellectual, to his persuasion of the evidence and argu
تعد التغيرات المناخية قضية بيئية عالمية وشاغلاً مشتركاً للبشرية وهي نتيجة حتمية للتطور الحضاري، لاسيما بعد قيام الثورة الصناعية، فقد كان الاستهلاك غير العقلاني لموارد الطبيعة والتوسع العمراني على حساب المساحات الخضراء آثار خطيرة على المناخ الذي يعد من اهم عناصر البيئة الطبيعية لما له من اثر واضح على كافة مجالات الحياة. على صعيد الحالة العراقية يواجه العراق تحديات عدة يفرضها تغير المناخ كارتفاع درجات الحرا
... Show MoreStop and stop Alsergsti classed many of the characteristics of great poets and
literary arts and persuasions, in Mqamth cash cash Antzmtha three criteria: the
standard of Islam and the standard time, and Maaartadd purposes of poetry. This
has had its effect on lighting stand many of the goals of the poets and their
attitudes.
The first criterion: Those who study the positions of Alsergsti to poetry and
poets must be discerned his money comes from the spirit of Islam as a religion and
creed and a system, a position that is encouraging him wherever expressed, such as
the Muslim community the new values, away from the vulgarity, which contributed
to the formulation of the standard of religious poetry criticism.
Husain as a king of Iraq.
This paper deals with the British communication with faisel . then Winston Churchill's speech in British common house .then fodlowed by arriving faisal to Iraq after that the referend um faisel .
The his claims of British maneuver lastly coronation on faisal & his inauguration as a king of Iraq.
It is summarized that Abu-Baker Al-Soly is one of Arabic Muslim scientists who had special style in literary writing specifically in sciences and knowledge that had depended on the encyclopedia culture gained from various fields of science , this means that he was an individual who had participated to characterize features of Islamic –Arabic history enhanced the rules of it , this matter would encourage us to know the method and style of writing in the field of intellectual life in which the writer depended on the procedures direction of scientists that he lived in the Abbasid era .
يعد التأمين أحد المؤسسات المالية ذات التأثير على برامج التنمية ، وما زال قطاع التأمين يعاني من العديد من المشاكل منها الوعي أو التشريع أو كيفية توظيفه كمورد اقتصادي واجتماعي خدمة للمجتمع والمؤسسات والافراد. وحيث أن التأمين يقدم خدمة تستوجب التزامها بمواصفات محددة ، لذا أصبح من الضروري دراسة آليات تحسين جودة الخدمة التأمينية وكذلك دراسة واقع العملية التسويقية للخدمة التأمينية وما ينالها من تحديات داخلية أ
... Show More