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.
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Abstract Definition of the specifics of color designation and color painting by M. Sholokhov. The general goal of the study determined the formulation and solution of the following tasks: -identify the color words «black» and «white» in the book of the novel, determine their semantics and frequency of use; -show the compatibility of color words in order to detect typical contexts for the implementation of aesthetic and social meanings of color vocabulary,. We determined the composition of the lexical-semantic group is based on the commonality of the logical-subject content of adjectives or their individual meanings, which is detected by the presence of connections between lexical meanings. Semantic connections between lexical meanings a
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The study evaluated the effect of adding quercetin to some characteristics of the sperm of the ram. This study was conducted in the animal field, Department of Animal Production, College of Agricultural Engineering Science, University of Baghdad for the period 5/12/2021 to 20/2/2022. In this experiment, 3 rams were used at the age of 2-2.5 years and weighed 50-55 kg. The semen was collected early in the morning and once a week and the semen was pooled to remove the individual differences. The treatments were divided: quercetin-free control group, treatment T1 (3 µL/mL quercetin), T2 treatment (6 µL/mL quercetin), T3 treatment (9 µL/mL quercetin). The result of the study showed
... Show MoreThis paper is a review of the genus Sitta in Iraq, Five species of this genus are recognized
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on nest building and nest sites of S. tephronota supporting by figures are presented.
Commercial banks represent the main pivot in financing national economic activity and its development. The capital represents safety margin to depositors and represents a defense line that protects bank work from dangers. Basel committee requirements represent protection and comprehensive supervision to bank activities for depositors, debtors and the bank. It provides trust in bank dealings and tackles activities of high dangers. The most prominent of these requirements are capital adequacy that concerns bank management and supervision and auditing bodies such as the central bank and protecting banks that suffer weakness in its vital important borrowing activity that reflects weakness in implementing borrowing policy .The purpose
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... Show MoreThis study was attempted to determine optimum conditions, for Glutathione s-Transferase enzyme, in sera of three groups diabetic patients type1 depending on duration of disease without complications compared with control group. The aim of this study was to find optimum conditions were determined such as (pH, Substrate Concentration, Temperature, Incubation time, Enzyme concentration, and effect of(0.15M)(0.25M) of mono divalent compounds). And to find the kinetics parameters in the three groups of diabetic patients when compared with control. It was found optimum pH(8.5,4.5,2.5,6.5).Temperatures(20cº,40cº,50cº,30cº). Incubation times (7min, 4min, 4min, 5min) substrate concentrations (12µl, 10µl, 5µl, 10µl) enzyme concentra
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