The design, construction and investigation of experimental study of two compound parabolic concentrators (CPCs) with tubular absorber have been presented. The performance of CPCs have been evaluated by using outdoor experimental measurements including the instantaneous thermal efficiency. The two CPCs are tested instantly by holding them on a common structure. Many tests are conducted in the present work by truncating one of them in three different levels. For each truncation the acceptance half angle (θc) was changed. Geometrically, the acceptance half angle for standard CPC is (26o). For the truncation levels for the other CPC 1, 2 and 3 the acceptance half angle were 20o, 26o and 59o, consequently. A significant difference between the instantaneous thermal efficiency of 3.86× CPC (θc=20o) and 2.32× CPC (θc=26o), and between that for 3.61× CPC (θc=26o) and 2.32× CPC (θc=26o). It's noticed that the difference between the instantaneous thermal efficiency of 2.32× CPC (θc=59o) and 2.32× CPC (θc=26o) is small compared with the difference of the first and second cases, the instantaneous thermal efficiency of 2.32× CPC (26o) was higher than those for other three CPCs. The experimental results show that the maximum thermal efficiency of the full 2.32×CPC (26o) is 0.708, the maximum thermal efficiency of the 3.93×CPC (15o), when it's truncated to 3.84× CPC (20o), 3.61× CPC (26o) and 2.32× CPC (59o) are 0.51, 0.52 and 0.66, respectively. As the concentration ratio decreases from (3.93× to 1×), the thermal efficiency, energy losses and optical efficiency increase from (0.47 to 63), (1.58 to 7.2 K.m2/W) and (0.494 to 0.797), respectively.
An experimental study is conducted on the utilization of the inlet ethanol injection technique in order to evaluate its impact on the performance of a two-shaft T200D mini-gas turbine engine. The maximum degradation recorded in power output was 32.8% at the climate temperature of 45oC. Nevertheless, at that temperature, adding ethanol with Eth/LPG ratio of 20% by volume brought an enhancement in power output of 19.2% compared to normal LPG run. SFC of the dual-fuel engine ranked a level of 22% higher than that with pure LPG consumption. The overall efficiency suffered a maximum reduction of 14.4% with Eth/LPG fuel ratio of 20%, but when the loading was raised beyond 70% of the engine full load; the efficiency of dual-fuel engi
... Show MoreReduce the required time for measuring the permeability of clayey soils by using new manufactured cell
Abstract
The research aims to shed light on strategic cohesion and its dimensions represented by (strategic logic, organizational excitement, organizational founding, organizational synergy) and measure its impact on achieving organizational prosperity and its dimensions represented by (intellectual capital, innovation, infrastructure, organizational agility, sustainable competitive advantage). The research problem emerged by raising the main question, which is: Does the management of the researched company realize the importance of practicing strategic cohesion and its role in achieving organizational pros
... Show MoreAdvertising design is one of the arts of communication of various levels and one of the aspects of the fields of design arts, and that the construction of the design environment in the advertising is one of the important entry points in making the recipient feel this environment and feel as if being one of its elements. It is an entrance worthy of study and research and is a problem worth raising according to the following question: - What is the effectiveness achieved in the virtual design environment for digital advertising? The two researchers dealt with the research in three frameworks, the methodological framework which identified (the problem of research, its importance, purpose, limits, and the definition of ter
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After we completed this book search we must extraction most important the findings.
Event of war a majar impact on same as all human being but signed and its impact in the
psyche of iraqi woman unparalleled result of the suffering that were produced by these wars
that contributed to the destabilization of Her life at all levels a woman has lost her father,
husband and son an brother as well as extreme poverty caused by the economic blockade
brought in to existence wars that exacerbated the suffering was the woman to work and
economic in order to provide a living for her and her family and pre – empt the dreams and
ambitions so he excelled writer Iraqi in portraying the succession of wars that ate every thing
and
الخلاصة
يجمع المختصون أن ليس من نقد إلا وكان مُرحِّلا لنظرية لسانية إلى فضائه، فكان أثر اللسانيات السوسيرية، ومن ثم اللسانيات التوليدية التحويلية معروفا، ولم يكن هذا الأثر محدودا باللسانيين أو نقاد الأدب فحسب، بل امتد إلى الشعراء والجماليين أيضا. وفي هذا البحث سنتوقف عند أثر اللسانيات الوظيفية، وهو ما لم يتوقف عنده إلا قلة من المختصين. ولن نقف عند نقد الوظيفيين للشعر، بل سنقف عند نقدهم للرواية، بقراءة
... Show MoreThe oil and gas production industry is considered the most important industries in the modern world because of its large relative significance among the group of energy recourses required for the world, where the natural resources represent the oil and natural gas fields, phosphate, gold, coal, forests and others. The most important advantage of the natural resources is its need for huge financial investments for a relatively long period of time from the beginning of the work until the start of extracting natural resources. Also, there are numerous cases where the natural source is not feasible exploited economically and is not discovered until after the passage of a long period of time from the start of work and paying relatively high a
... Show MoreAcademic achievement is a professional standard for measuring student levels in the first stages. Therefore, any indication of the level of achievement makes us in an attempt to employ students in evening schools. The researcher has developed a closed questionnaire of (36) paragraphs. A total of (164) male and (24) female students were chosen from evening schools. The result of this research revealed that the number of students was a reason for the low level of their achievement, the lack of laboratories, educational methods, and techniques of the most prominent problems confirmed by students in these schools. In addition, to support educational institutions with their necessary needs. The most important conclusion in this research is th
... Show MoreAbstract
The research aims to identify the nature of the relationship between the level of debt used and economic value added of companies listed on the Iraq Stock Exchange under the Contrast sizes of these companies , The research addressed the theoretical concepts associated with each of the debt financing , economic added value and Organization size With the use of financial techniques in the practical side to measure these variables, The research community Represent of the shareholding companies listed on the Iraq Stock Exchange with a choice of intentionally sample of 24 joint stock companies representing 
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(3)
The moral aspect is an important one in the structure of personality , and the lack of moral aspect is responsible for what we suffering today from problems . there is no exaggeration to say that many of our current problems are moral problems , and reflects the lack of moral growth.
The goal of research is to build scale in order to detect the level of moral reasoning among junior high school students in Baghdad , The researcher followed the procedures in the construction of scientific standards in order to measur
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