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 progra

Several problems have emerged as a result of urban expansion or the connection of urban areas with rural areas. This process has led to the urbanization of rural areas, and to have overlapping edges and margins of areas, which were outside the basic design of the city. Accordingly, the present research assumes that the accelerating growth of Baghdad population has contributed significantly to the process of unplanned urbanization. Thus, the study aims to examine the factors that have led to an increase of urban sprawl at the expense of the agricultural land. The study has thus adopted the descriptive, analytical, and historical approaches relying on the simple linear regression method to predict the phenomenon of urban expansion and its

Expected to The organizational commitment by employees increases their loyalty towards their organization and thus contribute to enhancing their performance , therefore this study aimed to discover the relationship and the impact between the organizational commitment (emotional commitment, standard commitment, continuous commitment) and the performance of employees in the company researched, additional to know the available organizational commitment levels of employees in the company researched and its impact on the performance of employees, Research was conducted at the General Company for products in the dairy to achieve the goals of research has been developed questionnaire conation (22 ) items to collect data from the study s

The objective of this investigation was to study the effects of a mixture of three arbuscular mycorrhizae (Glomus etunicatum, G. leptotichum and Rhizophagus intraradices) on the development of fusarium wilt disease in tomato plants in the presence and absence of organic matter (peatmoss). Results indicated an increase in mycorrhizal root dry weight especially in the presence of the organic matter, on the other hand this parameter was significantly decreased when Fusarium oxysporum f. sp. Lycopersiciwas added simultaneously with the mycorrhiza, Moreover, mycorrhiza and organic matter significantly reduced the damping off seedling disease, disease severity and rate of infection of tomato leaves and roots caused by the pathogenic fungus, These

The heat transfer and flow resistance characteristics for air flow cross over circular finned tube heat exchanger has been studied numerically and experimentally. The purpose of the study was to improve the heat transfer characteristics of an annular finned-tube heat exchanger for better performance. The study has concentrated on the effect of the number of perforations and perforations shapes on the heat transfer and pressure drop across a staggered finned tube heat exchanger. The Numerical part of present study has been performed using ANSYS Fluent 14.5 using SST Turbulent model, while the experimental study consist from a test rig with different models of heat exchangers and all required measurement devices were build

Natural convection heat transfer is experimentally investigated for laminar air flow in a vertical circular tube by using the boundary condition of constant wall heat flux in the ranges of (Ra_L) from (1.1*10⁹) to (4.7*10⁹). The experimental set-up was designed for determining the effect of different types of restrictions placed at entry of heated tube in bottom position, on the surface temperature distribution and on the local and average heat transfer coefficients. The apparatus was made with an electrically heated cylinder of a length (900mm) and diameter (30mm). The entry restrictions were included a circular tube of same diameter as the heated cylinder but with lengths of (60cm, 120cm), sharp-edge and

Steady natural convection in a square enclosure with wall length (L= 20 cm) partially filled by saturated porous medium with same fluid (lower layer) and air (upper layer) is investigated. The conceptual study of the achievements of the heat transfer is performed under effects of bottom heating by constant heat flux (q=150,300,450,600W/m2 ) for three heaters size (0.2,0.14,0.07)m with symmetrically cooling with constant temperature on two vertical walls and adiabatic top wall. The relevant filled studied parameters are four different porous medium heights (Hp=0.25L,0.5L, 0.75L, L), Darcey number (Da1) 3.025×10-8 and (Da2) 8.852×10-4 ) and Rayleigh number range (60.354 - 241.41), (1.304×106 – 5.2166×106 ) for Da1 and Da2 cases respecti

   Form of investment in infrastructure important factor to drive economic growth in any country, with the dwindling ability of governments to provide the necessary funds for such investments, emerged as a rising trend for private sector involvement in public projects and infrastructure, and one of these trends is the build-operate-transfer system (BOT), which commonly used in various developed and developing countries as one of the tools used in the implementation of these investments, as the private sector under this system design, finance, build and operate the project, and are re-administration of the state after a certain period under a contractual agreement between the parties of the contract. As this system provides majo