A paraffin wax and copper foam matrix were used as a thermal energy storage material in the double passes air solar chimney (SC) collector to get ventilation effect through daytime and after sunset. Air SC collector was installed in the south wall of an insulated test room and tested with different working angles (30o, 45o and 60o). Different SC types were used; single pass, double passes flat plate collector and double pass thermal energy storage box collector (TESB). A computational model based on the finite volume method for transient tw dimensional domains was carried out to describe the heat transfer and storage in the thermal energy storage material of collector. Also, equivalent specific heat method was employed to describe the heat storage and release in the mushy zone. Experimental results referred to an increase in thermal conductivity of paraffin wax that supported by copper foam matrix more than ten times. While the ventilation effect was still active for hours after the sun set, depending on the heat storage amount. Maximum ventilation mass flow rate with TESB collector was recorded with value equals to 36.651 kg/hr., when the overall discharge coefficient that was calculated for the system equals to 0.371. Experimental results showed that the best working angle range was 45~60o, and the highest air to the collector approaching temperature appeared to the double passes flat plate collector. Results gave greater heat storage efficiency of (47)% when the maximum solar radiation was 780 W/m2 at 12.00pm, while the energy summation through duration charge time was 18460 kJ. Computational results, depending on the equivalent heat capacity method for heat storage or release from phase change material that supported by copper foam matrix, showed the behavior of paraffin wax melting and solidification situation through periodic for charge and released heat from the solar collector. Also, these results gave agreement approaching the experimental results for the heat storage in the combined heat storage material, with standard error of 16.8%.
يرمي البحث الحالي الى تقويم أداء طالبات الصف الاول متوسط في مهارات القراءة الجهرية ، وذلك من خلال الاجابة عن هدفي البحث : 1- ما مستوى أداء طالبات الصف الأول المتوسط في كل مهارة من مهارات القراءة الجهرية ؟ 2- ما مستوى الأداء العام لطالبات الصف الأول المتوسط في القراءة الجهرية ؟ يقتصر البحث الحالي على: 1- مهارات القراءة الجهرية 2- عينة من مدارس البنات الن
انصبت هذه الدراسة على قياس جودة الخدمة، وبوجه خاص ماهية أبعاد جودة الخدمة التي يجري قياسها للوصول إلى مستوى جودة الخدمة. وتم التطبيق على خدمة التعليم العالي الخاص، حيث جرى اختيار عينة من طلبة جامعة خاصة لتعبئة الاستبانة الخاصة بالدراسة. وكان هناك 360استبانة تم تحليل البيانات فيها من خلال مؤشرات الإحصاء الوصفي، وتحليل الارتباط، وتحليل الانحدار المتعدد. وقد توصلت الدراسة إلى وجود علاقة ارتباط بين مستويات
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Ali Şir Nevai’nin vücuda getirdiği edebi Çağatayca, edebi ve canlı bazı Türk şivelerinin işlenmesinden ve kaynaşmasından hasıl olmuştur. Bu gün bu dilin
fonetik bünyesi hakkında, en çok bilgi veren, yine Nevai’nin kendisidir. Onun―Muhakeemet-ül-luğateyn‖ adlı eseri, bu bakımından büyük bir değer taşımaktadır.Bu eserinde Nevai, bir taraftan Türk dilinin Farsçaya üstünlüğünü ispata kalkışken, bir taraftan da kendi Türkçesinin fonetik ve morfolojik özelliklerini belirtmiştir. O, Arab imlası kaidesi üzerine ayni şekilde yazılarak, semantik yönden başka başka manalarda kullanılan kelimeleri sıralarken, açık bir surette, edebi Çağataya şivesinin fonetik bünyesini d
This search aims to meditate Divan of Hazem Al-Qirtagni his incomplete contiguous and non-contiguous naturalizations are investigated through two interrelated sections, the first is contiguous deficient naturalization and the analysis of phonemic symmetry in the light of syntactic syntax
This study deals with it the era of Taher Bin Al Hussein for his son Abdullah when preside Diyarbakir and Rabia in succession of ALMa`amoon Abbasi in the political and historical dimensions
The current study deals with the Islamic Arab of Mongolian invasion in the Island of Euphrates. We have exposed conditions of Levant before the Mongolian invasion and that includes situations of princess of Levant and their caliphates , they have been unaware the danger surrounding them and their country. It has also included the Islamic Arabic threat through the integration of Islamic Arabic cities residents in Levant to confront
It was the sayings of Andalusia scholars in agriculture based on experiments and theories that helped a lot in the success and development of agriculture in the Andalusia ,and also The divisions of the soil and out types and forms it helped a lot of to know arable of non-arable land earth and all off the determination of the color of repentance is important often discovered by agricultural scientists and that helped in the cultivation of certain crops in certain land without another land.and though each particular agricultural crops specific soil in which to live and not live in other soil ,
تعد الجامعات من أهم المؤسسات المجتمعية التي تؤثر وتتأثر بالجو الاجتماعي المحيط بها، فهي من صنع المجتمع من ناحية، ومن ناحية أخرى هي أداته في صنع قياداته السياسية، الفكرية، الفنية، والمهنية، ومن هنا كان لكل جامعة رسالتها التي تتولى تحقيقها، فالجامعة في القرن العشرين تختلف رسالتها وغايتها عن الجامعة في القرن الحادي والعشرين. ولكي تقوم الجامعة بدور أفضل في خدمة المجتمع وتحمل المسؤولية المجتمعية فلابد لها من وض
... Show MoreThe phenomenon of multi-class construction and landlords has increased in Iraq, and this is not justified except because of the change in the economic and social conditions in it, because like any social system interacts with what happens in society, whether it is positive or negative, and since the vertical housing system contains common parts and these parts need to Maintenance and preservation, and in order to continue to perform the construction and other parts in an effective and regular manner for a long period of time and with appropriate efficiency, it must be maintained, and maintenance is one of the most important and difficult problems facing the partners. It is recognized that it is not possible to understand these practical dif
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