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).
ان هدف من هذا البحث هو تحليل محتوى كتاب الفيزياء للصف الرابع العلمي و المقرر تدريسه للعام الدراسي (2018-2017). ولتحقيق هذا الهدف، و بعد مراجعة الادب السابق في ضوء مفاهيم التنمية المستدامة، تم تطوير اداة تتضمن مفاهيم التنمية المستدامة وابعادها، حيث تكونت في صورتها النهائية من 51قضية فرعية موزعة بين المفاهيم الثلاثة الساسية: الاجتماعية، والاقتصادية، والبيئية .وبعد التأكد من صدق الاداة وثباتها، تم تحليل محتوى كتاب
... Show MoreThis research deals with study and analyze the industrial buyer behavior and identified its objectives by determine the nature of selection the members of the purchases committees and determine the role of the purchases committees to provide requirements of the educational and scientific process and knowledge Impact of the factors ( environmental , organizational , social , and individual ) and positions of the purchase in the behavior of the members of the purchases committees and starts the importance of research in it helps university administrations in the correct choice for the members of the purchases committees and gives a picture of professional conduct professional who is supposed to b
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- The study aimed to identify the position of the university leaders from the proposed abolition of the Ministry of Higher Education in Jordan as un approach for the development of society, the study relied descriptive method survey with the assistance consists of (33) items, and check validity and reliability of the instrument, and was applied to a sample of university leaders, (57) a leading university presidents and their assistants and deans and their assistants, and after processing the data bagful statistical( spss) overall results showed the to arithmetic average of (2.74) and the degree of medium and this means that most respondents moderately support the abolition of the ministry, the most prominent item that makes
Improving speaking skills of Iraqi EFL students was the main purpose of the current research. Thirty EFL students were selected as the research participants for achieving this aim. All students completed the pretest and then spent the next 25 weeks meeting for 90 minutes each to present their nine lectures, answer difficult questions, and get feedback on their use of language in context. Progressive-tests, posttests and delayed post-tests followed every three courses. The researcher utilized SPSS 22 to anal Analyze the data descriptively and inferentially after doing an ANOVA on repeated measurements. It has been shown that using the ideas of sociocultural theory in the classroom has an important and positive impact on students of
... Show MoreSustainable development (SD) is an improvement that meets present needs but jeopardizes the ability of new populations to do the same. It is vital to acquaint EFL students with the terminology and idiomatic expressions of this discipline. Nowadays, sustainable development and the environment have been prioritized in every aspect of life. Since culture and the teaching of Foreign language English cannot be separated, the English language becomes the mean of communication in health, economics, education, and politics. Thus, integrating sustainable development goals within language learning and teaching is very important. This descriptive quantitative study aims to investigate the perception of EFL pre-service teachers of sustainable develo
... Show MoreThe architecture Greek first civilizations, which focused on the design and planning of cities taking into account the percentages aesthetic and artistic forms beautiful and characterized Greek civilization styles three league and Ionian and Corinthian, has launched these names on this models relative to the form of
This research attempts to propose production and acquisition of scientific knowledge among the students of educational science faculties in some universities Governmental Jordanian (Yarmouk, Jordan, Muta). In addition to sources of educational gained in some of the Governmental Jordanian universities (Yarmouk, Jordan, Muta), and to propose the necessary socio-cultural dimensions of knowledge acquisition and production, using developmental screening method, which is represented in the study design tool (questionnaire), which consisted of 4 scales, scale: The reality of the acquisition of knowledge / reality of the production of knowledge / social dimensions of knowledge acquisition and production / cultural dimensions of knowl
... Show Moreأجري هذا البحث في العراق/محافظة ديالى، وهدف إلى تعرف أثر إستراتيجية شكل البيت الدائري في الاداء التعبيري لدى تلاميذ الصف الخامس الابتدائي,وبلغت عينة البحث(75) تلميذا بواقع (40) تلميذا في المجموعة التجريبية و(35)تلميذا في المجموعة الضابطة ، وأجرى الباحث بينهما تكافؤا في المتغيرات الآتية (العمر الزمني محسوبا بالشهور، والتحصيل الدراسي للأبوين ، ودرجات اللغة العربية للعام الدراسي السابق واستعمل الباحث أداة م
... Show MoreThe current research seeks to identify the impact of Barman's model on acquisition of the concepts of jurisprudence of worship among students of the departments of Qur'anic sciences. To achieve the research objectives, the researcher relied on the experimental method through a design with partial control by relying on two experimental groups receiving teaching by using the Barman model and a control group receives teaching through the normal method. After applying the experiment, the study reached the following results: Students of the Department of Qur’anic Sciences in general need educational programs linked to the curriculum and built on scientific foundations, according to their needs and problems (psychological, cognitive, and soc
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The research aims to find out the effect of PEDODE Strategy on the acquisition of historical concepts of First Intermediate Grade. To achieve this goal, the researcher has put forward this zero hypothesis: There is no statistically significant difference at the level of (05,0) between the mean of the students' marks in the experimental group who study the history subject using PEDODE strategy and that of the students' marks in the control group who study the subject according to the traditional method in the post-testing on the acquisition of historical concepts. The sample of the study consists of (62 female-students) of First Intermediate Grade in the Directorate of Baghdad Education/ Karkh2nd for the academic year 2016-2017. The sampl
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