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%.
The Arabic language is one of the important magazines that issued in our contemporary history not only on the Iraqi level but according Arabic one as well because it considered
تزخر ذاكرة بغداد ب سماء العديد من الشخصيا ث في الناشطة والبارزة والتردي
لهذا الاثر البارز والمثير في ميدان الابداع و
The study of the Baghdad personalities is an important issue because the owners of these personalities usually belong to the elite, which play a distinct role in the development of any society in all political, economic, social and cultural fields. These include the study of the personal personality of Father Anastas Marie Carmeli to highlight many aspects of personality And his clear fingerprints on the movement of society in the field of culture and thought
That Karamli's efforts in the field of language, literature and history made him one of the most prominent pioneers of Renaissance late in the history of modern Iraq
The government gave the muslims additional things to the sum of money ,it was al rizq which was given to the mujahidin .
Those who distributed the ata where called al urafa ,they were from the best biography people
The influx of Arab Qahtani and Nizari tribes continued to the countries of Baluchistan and the Levant in pre-Islamic times until the Levant became open to the Arab-Islamic tide during the first century AH. The Islamic Orient until the early Islamic Arab Army reached the western borders of China. What we will see in the folds of the search.
يهدف البحث الى دراسة مسالة مهمة اجتماعية ذات طابع اسري يعني بالاهتمام بالطفل من ناحية العناية والرعاية حين افتراق الابوين
The study of the Baghdad personalities is an important issue because the owners of these personalities usually belong to the elite, which play a distinct role in the development of any society in all political, economic, social and cultural fields. These include the study of the personal personality of Father Anastas Marie Carmeli to highlight many aspects of personality And his clear fingerprints on the movement of society in the field of culture and thought
That Karamli's efforts in the field of language, literature and history made him one of the most prominent pioneers of Renaissance late in the history of modern Iraq
Rights of child in the community crisis Iraqi child model The study aimed to identify the types of violation against children in the Iraqi crisis as well as to develop community coping mechanisms to these violations and promote the rights of the child health psychological , social and legal . the first chapter discusses the research problem and its importance and purpose of the research problem and its importance and purpose of the research and the most important terms in the A- Rights of the child ,B- crisis , chapter 2 rights of the child ensure the historical roots , of children’s rights in the holy quran and the sunnah, and legal rights through the twentieth century and the beginnings of century xx, the se through the twentieth cen
... Show MoreThe research includes a bout IL- IQulle , and their role in scientific of the Islamic – Arabic civilization , for Dr. Khlood M.Namma the proff in the collage of education for woman , Baghdad university , History department
ان تحقيق التطوير المطلوب في التعليم الجامعي يستلزم القيام ببحوث علمية تساعد في الوصول الى معادلات سليمة لأحداثه، وتجنب سلبيات التغيير غير المدروس وغير المخطط علميا ، والبحث الحالي هو محاولة في هذا الأتجاه، ويهتم بوضع خطوط عريضة تتضمن مجموعة الآراء والأفكار والتوجهات ذات الاهمية لتطوير دور التعليم العالي في تنمية العلم والتكنولوجيا، والتنمية البشرية ، أيضا في توجيه
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