A numerical investigation has been performed to study the effect of eccentricity on unsteady state, laminar aiding mixed convection in a horizontal concentric and eccentric cylindrical annulus. The outer cylinder was kept at a constant temperature
while the inner cylinder was heated with constant heat flux. The study involved numerical solution of transient momentum (Navier-Stokes) and energy equation using finite difference method (FDM), where the body fitted coordinate system (BFC) was
used to generate the grid mesh for computational plane. The governing equations were transformed to the vorticity-stream function formula as for momentum equations and to the temperature and stream function for energy equation.
A computer program (Fortran 90) was built to calculate the bulk Nusselt number (Nub) after reaching steady state condition for fluid Prandtl number fixed at 0.7 (air) with radius ratio ( =2.6), Rayleigh number (Ra=200), Reynolds number (Re=50) for both concentric and eccentric cylindrical annulus with different eccentricity ratios (ε=0, 0.25, 0.50, 0.75) and angular positions (φo=0o
, 45o , 90o , 135o , 180o ).
The results show a reasonable representation to the relation between Nusselt number and (ε, φo). Generally, Nub decreased with the increase in (ε and φo). Also, results show that the best thermal performance for the inner cylinder was at the angular
position (φo=0o ) for eccentricity ratio (ε=0.25), while the maximum reduction in the rate of heat transfer for the inner cylinder was at the angular position (φo=180o) for eccentricity ratio (ε=0.75).
Comparison of the result with the previous work shows a good agreement.
Tax information system is one of the most important means that help the tax administration to reach the real income of the taxpayer, and the problem of research came in the General Authority for Tax ,The next question (Does the control carried out by the Central Bank on foreign remittances to reach the real income of the taxpayer). The research is gaining importance by focusing on the Central Bank's control over foreign remittances, and how to use this control to finance the tax information system. The relationship between the Central Bank's control over foreign remittances and the tax information system.The study has reached a number of recommendations, the most important of which are the following: The work of an integrated information
... Show MoreAn experiment was carried out in the vegetables field of Horticulture Department / College of Agriculture / Baghdad University , for the three seasons : spring and Autumn of 2005 , and spring of 2007 , to study the type of gene action in some traits of vegetative , flowery growth , yield and its components in summer squash crosses (4 x 3 = cross 1 , 3 x 7 = cross 2 , 3 x 4 = cross 3 , 3 x 5 = cross 4 , 5 x 1= cross 5 , 5 x 2 = cross 6). The study followed generation mean analysis method which included to each cross (P1 , P2 , F1 , F2 , Bc1P1 , Bc1P2) , and those populations obtained by hybridization during the first and second seasons. Experimental comparison was performed in the second (Two crosses only) and third seasons , (four crosses)
... Show MoreThis research seeks to unravel the components of the argumentative discourse in the Book ofʻRawdat al-MuhebbeenwaNozhatt al-Mushtaqeenʼ - The Garden of Lovers and the Promenade of Longing People – by Ibn Al-Qayyem Al-Jawziyah. This is because this book has a moderate discourse with a sound Islamic thought that is characterized by its sustainability, popularity, realism, and interaction with the successive developments of the new age. This reflects the intellectual maturity the composing process has reached in the philosophy of love and its educational bases in every place and time. To explore the componets, properties, and the working mechanisms of an argumentative discourse in Ibn Qayyem’s book, the present work has been conducted
... Show MoreThe goal of this study was to investigate the protein peroxidation role by measuring serum levels of advanced oxidation protein products (AOPP) in type 2 diabetic patients with or without retinopathy and comparing them to controls to see if circulating AOPP levels can be used as a detection biomarker for DR. And see which of the two widely used antidiabetic treatment groups had the most impact on this oxidative stress marker. The groups were divided into two subgroups: 1) 70 type 2 diabetic patients (36 male, 34 female), 35 with diabetic retinopathy (DR) and 35 with no evidence of DR, and 2) non-diabetic controls (11 male, 9 female) were chosen from Ibn AL-Haitham Hospital for Ophthalmology and a Specialized Center for Endocrinology and Dia
... Show MoreAbstract Background: Articular cartilage lesions in the knee joint are frequently seen,its treatment represents a challenge for orthopedic surgeons especially in young age patients and if left untreated,then they can progress to advanced osteoarthritis that may affect the functional status of the patients.Many treatment modalities had developed for these lesions, in the current study arthroscopic micro fracture plus intra articular whole bone marrow(WBM) injection was used as modality of treating these lesions. Objectives: to assess the effectiveness of arthroscopic micro fracture plus WBM intra articular injection as a treatment modality for knee articular cartilage lesions. Patients and Methods : a prospective experimental study was perf
... Show MoreIn this work, some of new 2-benzylidenehydrazinecarbothioamide derivatives have been prepared by condensation of thiosemicarbazide and different substituted aromatic benzaldehydes in presence of glacial acetic acid to give compounds (1-6), these compounds have characterized by its physical properties and spectroscopic methods. This work also included theoretical study to prove the ability of these compounds as corrosion inhibitors; The program package of Gaussian 09W with its graphical user interface GaussView 5.0 had used for this purpose; the methods of Density Functional Theory (DFT) with basis set of 6-311G (d,p) / hybrid function of B3LYP and semiempirical method of PM3 have been used, the study included theoretical simulation
... Show MoreBackground: The long term survival of dental implants is evaluated by the amount of crestal bone loss around the implants. Some initial loss of bone around dental implants is generally expected. There is reason to believe that reflecting a mucoperiosteal flap promotes crestal bone loss in the initial phase after an implant has been inserted. The surgical placement of a dental implant fixture is constantly changing and in recent years, there has been some interest in developing techniques that minimize the invasive nature of the procedure, with flapless implant surgery being advocated. The purpose of this study was to compare the radiographic level of the peri- implant bone after implant placement between traditional flapped surgery and f
... Show MoreThe study aimed to analyze the relationship between the internal public debt and the public budget deficit in Iraq during the period 2010–2020 using descriptive and analytical approaches to the data of the financial phenomenon. Furthermore, to track the development of public debt and the percentage of its contribution to the public budget of Iraq during the study period. The study showed that the origin of the debt with its benefits consumes a large proportion of oil revenues through what is deducted from these revenues to pay the principal debt with interest, which hinders the development process in the country. It has been shownthat although there was a surplus in some years of study, it was not
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