Preferred Language
Articles
/
GBedRo4BVTCNdQwCiEB8
Experimental study of natural convection heat transfer on an enclosure partially filled porous medium heated from below by constant heat flux
...Show More Authors

This study reports on natural convection heat transfer in a square enclosure of length (L=20 cm) with a saturated porous medium (solid glass beads) having same fluid (air) at lower horizontal layer and free air fill in the rest of the cavity's space. The experimental work has been performed under the effects of heating from bottom by constant heat flux q=150,300,450,600 W/m2 for four porous layers thickness Hp (2.5,5,7.5,1) cm and three heaters length δ(20,14,7) cm. The top enclosure wall was good insulated and the two side walls were symmetrically cooled at constant temperature. Four layers of porous media with small porosity, Rayleigh number range (60.354 - 241.41) and (Da) 3.025x10-8 has been investigated. The obtained data of temperature from testing rig are used to extract the temperature distribution, local Nusselt number and average Nusselt number. Moreover, a comparison between the numerical result of the same problem published recently and present experimental results has been executed and discussed. It is evinced that; the heat transfer and fluid flow are affected by thickness of porous layer and be maximum at porous layer thickness (0.25L) with larger heater length(20cm) and heat flux (q= 600 Watt/m2) which is approximately (180%) for the average Nu when compared with (Hp=0.75L). Also, the effect of the increasing in heater length (δ) on the averaged heat transfer enhancement is more pronounced for large heater size and 25% of average enhancement is achieved for (δ=20cm) compared to (δ=7cm). However, the greater temperature distribution is found at Hp=2.5cm and 5cm at bottom and first quarter of the cavity (heater surface height Y=0 cm and Y=5 cm) respectively and minimum temperature at top (insulation wall Y=20 cm). Nearly, same shape for heat transfer for different case with clearly difference at small heater (δ=7cm).

Scopus Crossref
View Publication
Publication Date
Tue Jan 08 2019
Journal Name
Iraqi Journal Of Physics
Effect of TiO2 on the sintering behavior and microstructure of stoichiometric spinel (MgAl2O4)
...Show More Authors

In this work, magnesium aluminate spinel (MA) (MgO 28 wt%, Al2O3 72 wt%) stoichiometric compound , were synthesized via solid state reaction (SSR) Single firing stage, and the impact of sintering on the physical properties and thermal properties as well as the fine structure and morphology of the ceramic product were examined. The Spinel samples were pressed at of (14 MPa) and sintering soaking time (2h). The effect of adding oxide titania (TiO2) was studied. The obtained powders were calcined at a temperature range of 1200 and 1400 °C. The calcined samples spinel were characterized by XRD, it showed the presence of developed spinel phase end also showed that the best catalyst is titania. The SEM image showed the high sintering temperat

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jun 12 2011
Journal Name
Baghdad Science Journal
The Effect of Chlorine Concentration on the Optical Constants of SnS Thin Films
...Show More Authors

Chlorine doped SnS have been prepared utilizing chemical spray pyrolysis. The effects of chlorine concentration on the optical constants were studied. It was seen that the transmittance decreased with doping, while reflectance, refractive index, extinction coefficient, real and imaginary parts of dielectric constant were increased as the doping percentage increased. The results show also that the skin depth decrease as the chlorine percentage increased which could be assure that it is transmittance related.

View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Fri Apr 05 2024
Journal Name
Techhub Journal
The effect of suggested exercises on improving the kinesthetic response of soccer goalkeepers
...Show More Authors

View Publication Preview PDF
Publication Date
Wed May 24 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Effects of the Zinc on Activity of Immune System in Male Albino Mice
...Show More Authors

   Effect of zinc chloride on the immune  functions was studied in male albino mice aged 6-7 weeks. It was administrated orally (1ml) in three concentrations (0.5ppm, 1ppm, 2ppm) for 9 days.         The results showed that the first concentration was not effective comparing with control while the second concentration increased the enhancement of immune system and the cell third one killed the mice 6 hours post administration, so we can conclude that the high dose of ZnCl2 could be harmful for all metabolism.

View Publication Preview PDF
Publication Date
Wed Jun 27 2018
Journal Name
Iraqi Journal Of Science
The Impact of the Extreme Air Temperatures on the Characteristics of Iraq Weather
...Show More Authors

     Air Temperature is mainly affect the condition of temporal and spatial weather. This influence may be very high on some weather variables such as pressure, humidity and winds, also the Extreme of these variables can be considered as an indicator of the impact and intensity of the pressure systems. The data of the European Centre for Medium-Range Weather Forecasts (ECMWF) during the summer months (June, July and August) of the period (2006 - 2017) were used to extract the Extreme ​​of Daily Maximum Temperatures (EDMT) for four stations in Iraq (Baghdad, Basra, Khanaqin and AL-Rutba). The results that the number of extreme cases characteristics is nine, one of which is the beginning of the season, and the other

... Show More
View Publication Preview PDF
Publication Date
Thu Sep 01 2016
Journal Name
Journal Of Engineering
Effect of Lime Addition Methods on Performance Related Properties of Asphalt Concrete Mixture
...Show More Authors

In the recent years, some of the newly constructed asphalt concrete pavements in Baghdad as well as other cities across Iraq showed premature failures with consequential negative impact on both roadway safety and economy. Frequently, load associated mode of failure (rutting and fatigue) as well as, occasionally, moisture damage in some poorly drained sections are the main failure types found in those newly constructed road.

In this research, hydrated lime was introduced into asphalt concrete mixtures of wearing course in two methods. The first one was the addition of dry lime on dry aggregate and the second one was the addition of dry lime on saturated surface dry aggregate moisturized by 2.0 to 3.0 percent of wa

... Show More
View Publication Preview PDF
Publication Date
Fri Apr 01 2022
Journal Name
Journal Of Engineering
Effect of Distributing Steel Fibers on Some Properties of Slurry Infiltrated Fiber Concrete
...Show More Authors

The slurry infiltrated fiber concrete (SIFCON) is nowadays considered a special type of high fiber content concrete; it is high strength and high performance material. This paper investigates the effect of spread steel fiber into the slurry mortar on some properties of SIFCON. According to fiber distribution, two sets were used in this investigation. The first set consisted of randomly distributing fibers inside the slurry. The second set was by placing the fibers in an orderly manner inside the slurry. Crimped steel fibers with an aspect ratio of (60) were used. Two different volume fractions percentage of (7% and 9%) by volume of mold were used in both sets for this study. Also, a w/c ratio of (0.35) and superplasticiz

... Show More
View Publication Preview PDF
Crossref (4)
Crossref
Publication Date
Mon Dec 03 2018
Journal Name
Journal Of Engineering
Studying the Effects of Different Polymers on Rheological Properties of Water Base Muds
...Show More Authors

This research is focusing on finding more effective polymers that leads to enhance the rheological properties of Water Base Muds. The experiments are done for different types of mud for all substances which are Polyacrylamide, Xanthan gum, CMC (Carboxyl Methyl Cellulose). This study shows the effect of add polymer to red bentonite mud, effect of add polymer to Iraqi bentonite mud, the effect of add bentonite to polymer mud. The mud properties of Iraqi bentonite blank are enhanced after adding the polymers to the blank mix, CMC gives the highest value of plastic viscosity and Gel strength than others; X-anthan gives the highest value of yield point and gel strength than others. For the red bentonite mud, Polyacrylamide ha

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Sep 07 2008
Journal Name
Baghdad Science Journal
Effect of Low Level Acute of Aflatoxin on Performance in Faw- Bro Broiler
...Show More Authors

This study was conducted in the Poultry farm of the animal during the Production department, Iraqi during the (Ministry of Science and Technology) period from 3-9-2001 to 8-4-2002. The objectives of this study were to evaluate the effect of low – level chronic aflatoxicosis on performance (body weight, feed conversion efficiency and mortality), Serum biochemistry and activity of some enzymes (GOT,GPT, ALKP, LDH). A total of 300 male chicks of broiler breeder (Faw–Bro) were used. Chicks at day 1 of age were fed diets contaminated with aflatoxine at levels of 0, 0.3, 0.6, 0.9, 1.2, and 1.5 the feeding period were extended to 8 weeks. The data were subjected to analysis of variance by the completely randomized design. The results showed

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Feb 27 2022
Journal Name
Iraqi Journal Of Science
On the Dynamics of One Parameter Family of Functions f_k (x)=kcsc(x)
...Show More Authors

     In this research, we study the dynamics of one parameter family of meromorphic functions . Furthermore, we describe the nature of fixed points of the functions in ,and we explain the numbers of real fixed points depending on the critical point . So, we develop some necessary conditions for the convergence of the sequence when .

View Publication Preview PDF
Scopus (1)
Scopus Crossref