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.
These researches have shown the magnitude of the influence that culture exerts on all human extensions and spaces. Rather, the conviction of many thinkers, researchers and specialists in the comprehensiveness of this influence is such that it is used as a starting point and perspective to explain the various aspects, manifestations, problems and practices. According to these perceptions, a man carries a cultural mind that is slowly formed throughout the young years of a man’s life and is completed upon reaching the age of maturity. Therefore, it has become evident in the behavioral, social and human sciences to acknowledge the multiplicity of human thought patterns as a natural result of the different cultures of peoples and societies.
... Show MoreThe aimes of this study is to investigate Optimism and Pessimism among university undergraduates including the first and fourth stage students ,the sample of this stoudy contained (326) students ,(166) male and (160) female, The researcher adopted a scale of Dember et al (1889) translated and adjusted to arabic version by Al-Dosoke (2001). The results have shown that students have optimism including the first and fourth stage and no significant difference between the students as far as ncluding the first and fourth study stage and gender, Implications of the results and recommendations for further research are discussed.
The concept of tolerance is gaining its importance in the midst of an international society suffering from violence, wars and internal and international crises. It is practiced by extremist and extremist forces and movements acting in the name of religion to exclude the different Muslim and non-Muslim people according to the unethical practices and methodologies of Islamic law and reality. , Cultural, civilization .. that distinguish our world today. The society today is suffering from the ideas of the intellectual and aesthetic views of the different ideologically, ethnically, culturally and religiously in the world of the South. This is what the end-of-history thesis of Fukuyama and the clash of civilizations represented to Huntington.
... Show MoreHS Saeed, SS Abdul-Jabbar, SG Mohammed, EA Abed, HS Ibrahem, Solid State Technology, 2020
Degradation of soil quality is an inevitable consequence of modifications to the characteristics of the soil that contribute to a decrease in ecosystem services. Numerous stressors, including chemical, biological, and physical ones, as well as those originating from both natural and artificial sources. The most prevalent kind of soil contamination that contaminates soil biota is agrochemicals. Soil is the most common place for xenobiotic dumping, which makes it the most probable source of other natural resources' pollution, such as surface and ground waters, based on the results of several studies. The danger to the environment posed by polluted soils is influenced by a variety of biological and physicochemical mechanisms that regul
... Show MoreBackground: Acute myocardial infarction
(AMI) is one of the most common diagnoses
in hospitalized patients. The stimulus that
initiates the acute inflammatory process in AMI
has not been identified. Conventional risk
factors account only for approximately half of
the patients with clinically apparent
atherosclerosis which can leads to AMI.
Recently a potential link between infectious
agents and atherosclerosis has been suggested
Objective: To find a possible association
between Helicobacter pylori (H. Pylori)
infection and AMI.
Method: We studied the prevalence of antiH. pylori antibodies in 94 patients who were
admitted with the diagnosis of AMI and a
similar number of healthy individuals w
Profound maternal hemodynamic changes occur in order to satisfy the demands of a growing foetus. Early in pregnancy, peripheral vascular resistance (PVR) lowers, generating a considerable rise in cardiac output. Many parameters are employed for measuring the LV systolic function with different echocardiographic modalities including: M-Mode echocardiography, two-dimensional echocardiography, three-dimensional echocardiography, tissue doppler imaging.
That writing about the Iraqi Museum, within this context that comes second only to the Egyptian Museum , in terms of the establishment , not least his affair in terms of the historical value of the effects that represent the civilization of Iraq and his history of the old , which stretches for thousands of years until it became a landmark and cultural landmarks the city of Baghdad salient .
The motive for the study of the subject of the Iraqi Museum upbringing and development until 1963 , we did not find a study documented by the independent research except for studies that are specialized to study the ancient history of Iraq and its effects was the outcome of efforts exploration missions archaeological that stretched across decades o