The enhancement of the thermal and thermo-hydraulic performance of a semi-circular solar air collector (SCSAC) is numerically investigated using porous semi-circular obstacles made of metal foam with and without longitudinal porous Y-shaped fins. Two 10 and 40 PPI porous material samples are examined. Three-dimensional models are built to simulate the performance of SCSAC: model (I) with clear air passage; model (II) with only metal foam obstacles, and model (III) with metal foam obstacles as well as porous Y-fins. COMSOL Multiphysics software version 6.2 based on finite element methodology is employed. A conjugate heat transfer with a (k-ε) turbulence model is selected to simulate both heat transfer and fluid flow across the entire computational domain. However, only the local thermal non-equilibrium (LTNE) model of heat transfer is applied in the porous regions. The findings demonstrated that adding metal foam as the novel proposed configuration particularity of model (III) may enhance the thermal efficiency by about 30%, and the outlet air temperature may rise to 7% compared to other models. Also, the performance evaluation factor of this model is greater than one in all cases. Additionally, the thermal enhancement is accomplished by occupying only 5% of the air passage volume, thereby including an associated pressure drop of minimal magnitude.
The research is a special case of semantics modern Iraqi art, especially with regard to the art of sculpture, and the exact Nasba sculpture, has included research, four chapters on whale1. The first chapter: which consisted of:A. The research problem.B. The importance of research.C. Find goal.H. Find borders.Kh. Determine the terms.2. Chapter II: The theoretical framework: which consisted ofA. The first topic: sculptured configuration.B. The second topic:1. The first axis: contemporary Iraqi sculpture.2. The second axis: the sculptor Jawad Salim.3. The third axis: Mohammed sculptor debateC. Theoretical framework indicators.D. Previous studies.3. Chapter III: proceedings: which included:A. Find community.B. The research sample.C. Research
... Show MoreThis paper presents an efficient methodology to design modified evaporative air-cooler for winter air-conditioning in Baghdad city as well as using it for summer air-conditioning by adding a heating process after the humidification process. laboratory tests were performed on a direct evaporative cooler (DEC) followed by passing the air on hot water through heat exchanger placed in the coolers air duct exit. The tests were conducted on the 2nd of December /2011 when the ambient temperature was 8.1°C and the relative humidity was (68%). The air flow rate is assumed to vary between 0.069 to 0.209 kg/s with constant water flow rate of 0.03 kg/s in the heat exchanger. The performance is reported in terms of effectiveness of DEC, satura
... Show MoreThe study aims to use the European Excellence Model (EFQM) in assessing the institutional performance of the National Center for Administrative Development and Information Technology in order to determine the gap between the actual reality of the performance of the Center and the standards adopted in the model, in order to know the extent to which the Center seeks to achieve excellence in performance to improve the level of services provided and the adoption of methods Modern and contemporary management in the evaluation of its institutional performance.
The problem of the study was the absence of an institutional performance evaluation system at the centre whereby weaknesses (areas of improvement) and st
... Show MoreThis research Sought to identify the correlation relationships and the impact of each of the job description and perceived organizational support, Excellent Job performance of the heads of academic departments in the faculties of the University of Sulaymaniyah Iraqi Kurdistan Region, totaling (89) as President, and to achieve this was Default plan includes research variables as well as the formulation of a number of preparation fundamental assumptions, and researchers used a questionnaire for this purpose as a tool head of the collection of data and information, as it was distributed (80) copies, and the number of retrieved them (76) a copy of a valid statistical analysis, as well as conducting personal i
... Show MoreThis work intends to develop an effective heavy metal-free modifier having properties comparable to traditional stabilizers and flame retardants, simultaneously being environmentally friendly and may be superior in many aspects. The important requirement focused on is: how to increase thermal stability and flame retardancy of flexible poly(vinyl chloride). Due to the typical materials now used with poly(vinyl chloride), which increases health and environmental concerns, utilizing a novel heavy metal-free additive will make poly(vinyl chloride) substantially safer. We have used an artificial silicate for this aim, which proved to be an efficient flame retardant and surprisingly showed excellent heat stabilizing effect. Thermal stabi
... Show MoreNew complexes were synthesized with Schiff base tetradentate ligand (L). The ligand was synthesized by the condensation reaction of the dimedone with 2-hydroxybenzohydrazide. The formula of complexes [M(L) (H2O)2].Cl2, where M represents Mn(II), Ni(II) Cu(II), [Co(L)Cl.H2O]Cl and [Zn(L)(H2O)2]Cl2.2H2O. The ligand was identified using m.p., UV-Vis, FT-IR, Mass, 1H-NMR, and C.H.N. These complexes were characterized using techniques including infrared, UV-Vis absorption, magnetic susceptibility, molar conductivity, elemental analyses, thermogravimetric analysis (TGA), chloride content determination using Mohr’s method, and atomic absorption spectroscopy. The measurements revealed that the complexes are electrolytic. FT-IR results dem
... Show MoreIn study of effective bioactive compounds, we have synthesized the Co((ІІ), Mn(ІІ), Fe(ІІ), Cu(ІІ), Ni(ІІ), and Zn(ІІ) complexes of the Schiff base derived from trimethoprim and2'-amino-4-chlorobenzophenone and characterized by spectroscopic (NMR, IR, Mass, UV–vis,), analytical, TGA studies and magnetic data .The solution electronic spectral study suggests the stoichiometry of the synthesized complexes and Elemental analysis detected the square planer and octahedral geometry of the compounds. The prepared metal complexes presented promoted efficiency versus the screened bacterial (Escherichia Coli and Staphylococcus aureus) antibacterial efficacy against (Staphylococcus aureus, Salmonella spp., E. coli, Vibrio spp., Pseudomona
... Show MoreIn study of effective bioactive compounds, we have synthesized the Co((ІІ), Mn(ІІ), Fe(ІІ), Cu(ІІ), Ni(ІІ), and Zn(ІІ) complexes of the Schiff base derived from trimethoprim and2'-amino-4-chlorobenzophenone and characterized by spectroscopic (NMR, IR, Mass, UV–vis,), analytical, TGA studies and magnetic data .The solution electronic spectral study suggests the stoichiometry of the synthesized complexes and Elemental analysis detected the square planer and octahedral geometry of the compounds. The prepared metal complexes presented promoted efficiency versus the screened bacterial (Escherichia Coli and Staphylococcus aureus) antibacterial efficacy against (Staphylococcus aureus, Salmonella spp., E. coli, Vibrio spp., Pseud
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