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%.
One of the rules concerning the control of civil transactions is the rule of no harm and harm, which was enacted by our Holy Prophet Muhammad (peace be upon him and his family). Scholars singled it out by research and investigation, and classified by non-scientists independent messages, showing the status of al-Qaeda in terms of its perception, meaning, branches and results, and the importance of this rule in the payment of damage and compensation for it has been provided by the Iraqi legislator generous within the provisions of Iraqi law in all its branches of public and private, as applied The judiciary Iraq The provisions of this rule have been issued and numerous decisions have been made to compensate for the damage and to give to ev
... Show Moreيواجه الكثير من الافراد مشكلات في التكيف، خاصة الطلبة الذين ينتقلون من المرحلة الدراسية الثانوية الى المرحلة الجامعية، حيث يرافق هذه البيئة الثقافية الاجتماعية العديد من الضغوط والمواقف التي تحتم على الطالب الوصول الى تكيف مثالي.
ان التعليم الجامعي يوفر مجالات عديدة للتخصص تعمل على تحقيق طموحات الشباب التي تناسب قدراتهم وميولهم واهتماماتهم، وهو بذلك يمثل نوعية من التعليم تختلف عن النم
... Show MoreMohammed Hassan Salman is one of the Iraqi national figures who put a clear mark to promote the health institution and to improve the Iraqi people, even it was written about him as "The man who struggled to fight the tuberculosis", He began to struggle against this social courage that has been killing hundreds of Iraqis since his joining of Association for combating tuberculosis in 1999 and his big role in the application of (B-C-G) for the first in Iraq.
The research problem lies in determining the beauty ranges between the receiver and the industrial product, The goal of the research, it is the definition of aesthetics in industrial design and its relation to the receiver, and the researcher outcome several conclusions of the, the most important was: 1. The role of accumulated experience, and their interaction with the vision of the artwork in achieving aesthetic perception and levels of artistic and aesthetic values and by the level of growth this taste of the recipient. 2. There are interactive and close relationship be the primary means for the integration of functional and aesthetic meaning the designer meant to get it to the receiver.
بعض الملاحظات على القانون رقم 35 لسنة 2007 قانون العمل الصحفي في كوردستان
شهد العصر الذهبي للإسلام تحول أساسي في مجال الزراعة عرف باسم "الثورة الزراعية الإسلامية" أو" الثورة الخضراء" أو "الثورة الزراعية العربية" ، وقد أتاح الوضع الاقتصادي العالمي الذي أسسه التجار المسلمون في جميع أنحاء العالم القديم ، نشر العديد من النباتات والتقنيات الزراعية بين أجزاء مختلفة من العالم ا
... Show MoreThis Study is concerned with The Fast communications in the wars of arab moslims until the middle of fourth century . it pointed to many communications for that , Like using the fast horses , and carrier pigeon , Almanader (Almanawin) wich used to tell for long distances , and drums , trumpets…
The research(the internal and external factors affecting the political system in
PAKISTAN) involves a series of effects interact both internally and external to affect the
stsbility of the political system.
Intrernally there are a lot of powers affecting the political map of PAKISTAN such as
military institution, political parties, judgement, religious schools……etc.of internal
factors, which represent one of the most important pressure points on the system.
Externally one of the most important external factors which affect internal stability is
Pakistani allision to USA in antiterrorism war. The Pakistani military institution was
involved in the war against Pakistani tribes leading to unstable security in Paki
The research aims to investigate the possibility of joint auditing in improving the market value of Iraqi companies listed on the Iraq Stock Exchange. The sample was represented by 10 Iraqi companies listed in the Iraq market for the period from 2014-2017 (2 years before implementation and 2 years after implementation) and the research was based on the idea that joint auditing enhances investor confidence and raises their level of security as a result of providing quality and reliable reports, and thus This indicates good news in the market that reflects on the performance of stocks and the market value of companies that adopt joint auditing. The results of the analysis indicate an improvement in the market value, but this improv
... Show Moreاهتم في الربع الأول بالمفاهيم النظرية للمناهج التي تقع في النقاط الخمس ، النقطة الأولى تتعلق بمفهوم الخطاب والخطاب المادي ، وقلنا أن الرسالة كانت مبنية على الجسد من البداية ، حتى قبل ذلك هناك ستكون فلسفة أو معرفة المنظمة. أما النقطة الثانية فتتعلق بالمفهوم الفينومينولوجي للخطاب ، ونحن في هذه المرحلة أهم الركائز التي قام عليها (إدموند هوسرل) في بناء مفهوم وصفي ضعيف. في النقطة الثالثة نكشف عن الظواهر المتعلقة ب
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