Many researchers used different methods in their investigations to enhance the heat transfer coefficient, one of these methods is using porous medium. Heat transfer process inside closed and open cavities filled with a fluid-saturated porous media has a considerable importance in different engineering applications, such as compact heat exchangers, nuclear reactors and solar collectors. So, the present paper comprises a review on natural, forced, and combined convection heat transfer inside a porous cavity with and without driven lid. Most of the researchers on this specific subject studied the effect of many parameters on the heat transfer and fluid field inside a porous cavity, like the angle of inclination, the presence of vibration, magnetic fields, and heat generation. They used different thermal and hydrodynamic boundary conditions, different geometries of cavity, and different saturated-fluids. Results manifested that the fluid and thermal characteristics enhance greatly as porosity increases at a high value of Darcy number. Also, vibrational effects are a dominant factor in the heat transfer process only at high Darcy and Reynolds numbers.
Abstract
What the research come to:
1- The presentation of the image of the proud person in this
mortal life appeared in several styles such as (conversation)
arousing the insert once and convincing in other time,
(confirmation) in all its types، (argument) scolding with the
gradual progress of time of the discourse .Interview and
parallelism are two of these styles with the presences of the
repetition style especially in the topics that has a reference to
the theme of (pride) being implied not directly stated. The
Koran discourse varied in its reference to the theme of pride
according to the context which is mentioned directly
(eighteen times) which formed one third of the number of
Both of the species Typha domengensis and Phragmites communis among the most important plant endemic in flora of Iraq from monocotyledon. Due to the similarity of the two species with each other in many morphological characteristics such as the environment where they live and the form of leaves and type of leaf venation and type of stomata….ets, also both of species belong to monocots plant therefore this research work was conducted find anatomical differences that have the same as taxonomic value to help distinguishing between both species under study. Through this research, we found great importance to the anatomical characteristics which we reached by studying the roots, stems and leaves sections f
... Show MoreThis research for university students dialectic unemployment and work, focusing on
serious discussion, accurate and provide opinions between specialists and those interested in
the university youth issues and identify them in the light of the dialectical relationship
between unemployment and work for the purpose interpreted accurate and access to reality
without coverage and linked to the movement of the changing society now and the situation
that is happening in Iraq, where the loss of the safety and the weakness of the determinants of
economic well-being and the decline of public and social health and the unemployment rate
security in the heart of - programs - and blocs parties that Tgtill public opinion in any
Through the study of social work and social policy ( problems of marginalization and empowerment opportunities ) and taken a theoretically descriptive and analytical and highliyhed the role of social work in social policy its achieved only through community intraction and paamong all parties and according to social policies include of material resources and haman and integrated in to the planning and development framework with the aim of providing social services for allsegments of society and become the study in social work that include the introducation / and five chapters each chapter in cludes several detectives and each complements the other .
1 – The absence of social development projects on social policy .
2 – social pol
This study deals with the thems of "in-betweeness" in the modern Afro-American Drama, drawing upon the accumulated literature of the colonial and postcolonial studies. In-betweeness appears in these studies under the canopy of the terms mimicry, hybridity and liminality which refer to a transformative, in-between state of being. It also refers to themutual relations holdingbetween man and his cultural space.
This concept is fitting the Afro-American playwright Amiri Baraka's plays and his violent, revolutionary theatre. In his play Dutchman (1964), Clay, the protagonist, is a good example of the two-ness or in-betweeness. He finds difficulty choosing between the ethnocentric white culture and the black culture.He allows
... Show MoreSome esters were prepared from reaction of different molecular weight of PVA with some acid chloride (prepared by reaction of acid with thionyl chloride or phosphorous pentachloride)in the presence of pyridine. The thermal and reological properties were studied. The increasing Of bulky groups decreasing stability of the thermal and reological properties.
This work illustrates an enhanced visible light photocatalytic degradation of methyl orange dye (M.O.) by employing BiOI / BiOCl composites prepared under room temperature and without any organic precursors. Various experimental parameters have been studied, namely; composition of the composite, irradiation time and cell material. Composition D which implied 75% BiOI and 25% BiOCl has shown the highest bleaching of M.O. dye. This confirms the optimum photo-sensitization phenomenon for this composition in comparison to others. In the optimum photo-sensitized composite the electron of the conduction band reveals better reducing power and the hole of the valence band exhibits more oxidative power than those of pure BiOI electron and hole. Acco
... Show MoreBackground: Tumor-like overgrowth lesions of the oral mucosa are pathological growths that project above the normal contour of the oral surface. A practical classification can be made according to the site of origin, the etiology and the histological appearance. The aim of this article is to evaluate and analyze patients with gingival and alveolar ridge tumor-like overgrowth lesions in terms of surgical treatment, diagnosis and outcome. Materials and Methods: Patients complaining of these lesions were treated by surgical excision under local or general anesthesia; the excised lesions were submitted for histopathological examination, during the follow up period the patients were examined for complications and recurrence. Results: Pyogenic gr
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