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Natural convection in an annular space provided with metal foam fins attached to the inner cylinder is studied numerically. The metal foam fins made of copper were inserted in different axial sections with three fins in each section. The temperature of the inner cylinder is kept constant while the annular outer surface is adiabatic. The thickness effect of the inner pipe wall was considered. Naiver Stokes equation with Boussinesq approximation is used for the fluid regime while Brinkman-Forchheimer Darcy model is used for metal foam. In addition, the local thermal non-equilibrium condition in the energy equation of the porous media is presumed. The effect of Rayleigh number and number of foam fins in the axial direction, on fluid flow and heat transfer characteristics, were examined. The current model was valid with the available published results and good agreement is noticed. Results showed that as the Rayleigh number increases the dominated of convection mode increases and average Nusselt increases. It was found that at Rayleigh of 106 Nusselt reached its higher value which is 4.6 for the case of adding seven axial metal foams. A comparison between adding foam fins and copper fins was established for a range of Rayleigh numbers between 104 and 106. It showed a good enhancement in Nusselt number and the greatest enhancement percentage was 45.9% at Rayleigh equal 106 for the case of using seven sections of foam fins. |
The use of different materials in the art of ceramics is considered a new form of contemporary philosophical trends. That was introduced to art as a result of societal changes and transformations and rapid technological development. And it plays a very essential part in the beauty of the artistic structure. The contrast of using different materials in ceramics is considered a part of the old historical achievements since the art of ceramics used to follow strict standards. Which does not apply to contemporary ceramic, Because recently, it has become free from any religious and social control and created a whole new intellectual context, heading to new horizons in which it works with the newly added materials as a strategy to ensure the a
... Show MoreThe advertisement is important in maximizing the resources of journalistic institutions. It helps them to perform their duties and also establishes their independence. However, this type of communication has often overlapped with other types of communication, including media and publicity.
Those in charge of the press bear responsibility in this regard, as some of them harness the advertisement for personal purposes; or detrimental to media content. Many communication authorities have drawn attention to the danger of confusing the concepts and levels of the three activities and have moved towards establishing rules to reduce overlap between them.
The aim of this research is to try to disengage the concept of advertising,
... Show MoreThe issue of peaceful coexistence between societies is the topic of the hour, as it is one of the important issues in this era, especially in days when conflicts and conflicts abound, and even wars in the name of religion, gender, race, language, and the like. The world, so that single-mindedness and adherence to one opinion and intolerance to it became the method of dialogue in our world today, as writing in the field of peaceful coexistence, peace-building, tolerance, pluralism, and acceptance of the other is one of the new fields of knowledge in Iraq in general and in Nineveh Governorate in particular, as peaceful coexistence is one of the basic needs And necessary for the presence of individuals in societies, and it requires the achi
... Show MoreEnglish is spoken by its native speakers in two different forms. Reduced form which marks the colloquial and rapid speech so that it is easily produced and a citation or unreduced form which is a characteristic of careful, emphasized and slow speech.
This paper investigates Iraqi EFL university students’ production of the two forms mentioned above. The sample chosen includes twenty fourth year students, of which ten are males and the other ten are females from the Department of English of the College of Languages of the University of Duhok in Kurdistan Region of Iraq in the academic year 2020-2021. The material tested is six connective words which represent the commonest ones in every-day co
... Show MoreConstructing a fine 3D geomodel for complex giant reservoir is a crucial task for hydrocarbon volume assessment and guiding for optimal development. The case under study is Mishrif reservoir of Halfaya oil field, which is an Iraqi giant carbonate reservoir. Mishrif mainly consists of limestone rocks which belong to Late Cenomanian age. The average gross thickness of formation is about 400m. In this paper, a high-resolution 3D geological model has been built using Petrel software that can be utilized as input for dynamic simulation. The model is constructed based on geological, geophysical, pertophysical and engineering data from about 60 available wells to characterize the structural, stratigraphic, and properties distribution along
... Show MoreConstructing a fine 3D geomodel for complex giant reservoir is a crucial task for hydrocarbon volume assessment and guiding for optimal development. The case under study is Mishrif reservoir of Halfaya oil field, which is an Iraqi giant carbonate reservoir. Mishrif mainly consists of limestone rocks which belong to Late Cenomanian age. The average gross thickness of formation is about 400m. In this paper, a high-resolution 3D geological model has been built using Petrel software that can be utilized as input for dynamic simulation. The model is constructed based on geological, geophysical, pertophysical and engineering data from about 60 available wells to characterize the structural, stratigraphic, and properties distri
... Show Moreمع ان افلاطون في الفصلين السابع والعاشر من جمهوريته يعري المسرح بوصفه عالما زائفا يعج بالأخيلة التي يتوجب على المرء ان ينبذها ويتمسك بعالم الحقيقة، الا إن هذا لا يعدم الأثر البالغ الذي تركتهُ أرائهُ على المسرح، قديمهُ وحديثهُ،تجربهً وتنظيرا .إن حكايته الإستعارية للكهف ،والتي تعد مسرحةً للأفكارِ، إن هي إلا وسيلة ينفذ من خلالها الى جوهر المسرح. لذا فان مسرحية ونظرية الكهف قد اصبحت حجر الزاوية في ما قد اص
... Show MoreNovel derivatives of 1-(´1, ´3, ´4, ´6-tetra benzoyl-β-D-fructofuranosyl)-1H- benzotriazole and 1-(´1, ´3, ´4, ´6-tetra benzoyl-β-D-fructofuranosyl)-1H- benzotriazole carrying Schiff bases moiety were synthesised and fully characterised. The protection of D- fructose using benzoyl chloride was synthesized, followed by nucleophilic addition/elimination between benzotria- zole and chloroacetyl chloride to give 1-(1- chloroacetyl)- 1H-benzotriazole. The next step was condensation reaction of protected fructose and 1-(1-chloroacetyl)-1H- benzotriazole producing a new nucleoside analogue. The novel nucleoside analogues underwent a second conden- sation reaction with different aromatic and aliphatic amines to provide new Schiff b
... Show MoreThe current study is designed to achieve the goal of early detection of heart disease because it is the main risk of death. Some biomarkers were measured as well as the percentage of the effect of certain risk factors in people with myocardial infarction and heart failure. The study included 40 serum samples from people with heart disease. The effectiveness of the creatine kinase (CK-MB), as well as its temporal and albumin effects, as well as sodium ions in people with myocardial infarction and heart failure, were compared with the control group. as shown below:
-The first group consisted of 25 blood samples from people with myocardial infarction and 15 serum samples from people with heart failure. Blood
... Show MoreABSTRACT
Metal (II) complexes of Co, Ni, Cu and Zn with cefdinir C14H13N5O5S2 derivative (L) were synthesized and identification by elemental analysis CHNS Uv-Vis, FTIR, TGA, metal analysis AA, magnetic susceptibility and conduct metric measurement. by analysis the ligand behaves as a bidentate. For the cobalt complex, Tetrahedral geometry shape was suggested, while other complexes that have nickel, copper and zinc ions were proposed as octahedral geometry shape. The experimental method was studied for prevention of corrosion carbon steel in 3.5% NaCl by using a novel Cefdinir derivations drugs. The results showed that metal complex was a strong corro
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