The steady state laminar mixed convection and radiation through inclined rectangular duct with an interior circular tube is investigated numerically for a thermally and hydrodynamicaly fully developed flow. The two heat transfer mechanisms of convection and radiation are treated independently and simultaneously. The governing equations which used are continuity, momentum and energy equations. These equations are normalized and solved using the Vorticity-Stream function and the Body Fitted Coordinates (B.F.C) methods. The finite difference approach with the Line Successive Over-Relaxation (LSOR) method is used to obtain all the computational results. The (B.F.C) method is used to generate the grid of the problem. A computer program (Fortran 90) is built to calculate the steady state Nusselt number (Nu) for Aspect Ratio AR (0.55-1) and Geometry Ratio GR (0.1-0.9). The fluid Prandtl number is 0.7, Rayleigh number Ra = 400, Reynolds number Re = 100, Optical Thickness (0 ≤ t ≤ 10), Conduction- Radiation parameter (0 ≤ N ≤ 100) and Inclination angle λ = 45. For the range of parameters considered, results show that radiation enhance heat transfer. It is also indicated in the results that heat transfer from the surface of the circle exceeds that of the rectangular duct. Generally, Nu is increased with increasing GR, t and N but it decreased with AR increase. When the radiation effect added to the heat transfer mechanism, the heat transfer rate increased. This effect increased with increasing in GR and decreasing with AR. The increasing in radiation properties lead to increase the radiation effect. Tecplot 7 program was used to plot the curves which cleared these relations and isotherms and streamlines which illustrate the behavior of air through the channel and its variation with other parameters. A correlation equation is concluded to describe the radiation effect. Comparison of the results with the previous work shows a good agreement.
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تعد أبي- سمتي واحدة من أهم النساء التي لعبت دوراً هاماً في الحياة الاقتصادية في عصر أور الثالثة (2112-2004 ق.م)، فقد برزت خلال حكم زوجها الملك أمار-سين (2046-2038 ق.م) وحكم الملك شو-سين (2037-2029 ق.م) وكان لها دور أداري هام في النصوص الاقتصادية فقد ظهرت في عمليات الأستلام وتسليم الماشية والنفقات والمدخولات، فهي على مايبدو كانت مسؤولة عن حظيرة أو مؤسسة ما خلال حكم زوجها وأخيه ومن أشهر تلك الحظائر كانت (حظيرة دريهم) التي كانت تحت
... Show Moreشغلت نظرية العدل الإلهي بال الأديب العراقي القديم، مما جعلته يثير عبر نصوصه الأدبية كثير من التساؤلات حول عدالة الإلهة، التي يعبدها ويقدم لها الهدايا وتساؤلاته هذه دفعت بالباحث إلى اختيارها عنوانا لموضوعه، إلا أن الدراسة ستختصر على نصوص معينة، والسبب في ذلك أنها كانت الرائدة في هذا الجانب، وفي اللحظة التي ينتقي فيها العدل الإلهي وتتحول الإلهة إلى كلاب تلهث وراء غرائزها، ذهبنا وراء الأسباب التي قادت إلى فقد
... Show MoreThe study aims to diagnose the levels of total costs borne by the Diyala State Company, then estimate and analyze the quantitative relationship between the different items of these costs, in addition to the impact of the productive activity on them. This was done by choosing the different variables affecting the costs and their different items for the company under study, and relying on the data issued by the company during the period (2002-2021), based on a methodology that combines the descriptive and econometric methods in order to estimate and analyze the cost function in the concerned company. According to the estimated function of the costs of the company under study, the study concluded that the value of production affects the total
... Show MoreThe process of doing many kinds of industries , crafts , professions around Islamic Arabian State , they enable us to say that Arab Muslims over their homelands had been occupied various types of crafts and manufacturing before emergence Islam . Moreover Islam encouraged to work within manufacture field . And These matters were clarified through verses of the Holy Qur’an and honored prophetic guidance ( Sunna ) . Whereas Arab Muslims applied principle “ Free of Business “ . They admitted to different social groups such as pact – fellows people to profession or craft which they desire to work . We have to not forget that Arab Muslims had broken all restraints and shackles which had restricted the worker bef
... Show Moreإن المعتقدات الخاصة بالسحر والعرافة قديمة جدا كون الإنسان عرف الكثير منها ومارس أنواع من الأساليب السحرية منذ أقدم العصور ومن أكثر العلوم التي حرم تعليمها ونشرها هو علم السحر والسيمياء أو الكيمياء والشعبذة والحيل . ومع ذلك عرف السحر من قبل سكان بلاد وادي الرافدين ولاسيما في بابل والسحر يمثل أقدم مرحلة في تطور العقل البشري .
The research aims to show the effect of some short-term debt instruments (central treasury transfers, cash credit granted to the government by commercial banks) on the production of the wheat crop in Iraq, through its effect on money supply during the period (1990-2018), As the study includes two models according to the statistical program (Eviews9), the first model included measuring the effect of short-term debt instruments on money supply, and the second measuring the extent of the money supply's impact on Wheat crop production, as the results of the standard analysis showed that the short-term debt instruments used in the model were Significant effect on wheat crop production indirectly through its effect on money supply, As
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Background: Poly (methylmethacrylate) is the most widely used material in denture fabrication. The characteristics of acrylic resin which support microorganism development can threaten the oral health of denture users. This study was assigned to prepareand incorporate Ag-Zn zeolite powder into heat cured denture base material as antimicrobial material and to investigate its effect on some properties of heat cured acrylic denture base materials. Materials and methods: Sliver –zinc zeolite was prepared by ion exchange method and characterized then incorporated into poly (methylmethacrylate) powder in0.5% by weight. Specimens were constructed and divided into 6 groups according to the using tests; each group was subdivided into 2 groups
... Show MoreBackground: The geriatric patients wearing removable partial dentures are increasing in proportion. At the same time, the root caries prevalence accompanied by gingival recession is increasing. A variety of vehicles can deliver fluoride into the oral cavity, including fluoride mouth-rinse, fluoride dentifrice, topical fluoride, and fluoride-releasing restorative materials, all of which effectively prevent root caries and suppress recurrent caries. This study aimed to evaluate the effect of sodium fluoride addition on some mechanical properties of heat cure acrylic denture base material. Material and method: A total of 90 samples were prepared in this study, then divided into three main groups according to the type of test used (hardness, te
... Show MoreThe Foreign Account Tax Compliance Act (FATCA) basically targets US citizens’ accounts hold at foreign banks and financial institutions blush, seems and non-financial sector by the Act:( retirement plan companies, investment funds, hedge funds and family investment companies.)
The non Compliance of Foreign of financial institutions act will lead to financial looses and harm regarding reputation, especially for the countries that rely on foreign relations in their financial and banking activities, in addition to deducting 30 % of their total incomes and sales coming from the USA. These institutions can avoid it by entering into agreement with the Internal Revenue Service's to be foreign financial institutions complied with the a
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