Preferred Language
Articles
/
joe-2986
EXPERIMENTAL INVESTIGATION OF LAMINAR NATURAL CONVECTION HEAT TRANSFER IN A RECTANGULAR ENCLOSURE WITH AND WITHOUT INSIDE PARTITIONS
...Show More Authors

Experimental study has been conducted for laminar natural convection heat transfer of air flow through a rectangular enclosure fitted with vertical partition. The partition was oriented parallel to the two vertical isothermal walls with different temperatures, while all the other surfaces of the enclosure were insulated. In this study a test rig has been designed and constructed to allow studying the effect of Rayleigh number, aperture height ratio, partition thickness, the position of aperture according to the side walls and according to the height, the position of the partition according to the hot wall, and partition inclination. The experiments were carried out with air as the working fluid for Rayleigh number range (5*107 – 1.3*108) and aspect ratio of (0.5). 22 different configurations of partition were used in this study these are:
a) Undivided enclosure (no – partition).
b) (21) Cork partitions of different shapes.
Empirical correlations for average Nusselt number are obtained for the different cases tested. The results show that heat transfer is independent on the partition position according to the cold wall and according to the upper or lower walls, while it shows that heat transfer is sensitive to:
1. Rayleigh number (Ra), which increase with increasing Ra.
2. Aperture height ratio (Ap=hp/H), which is found that when Ap= 5/6 (case 2,3), the reduction in heat transfer is 10.3%, while when Ap=1/2 (case 4,5), the reduction is 17.2% compared with the non partitioned enclosure.
3. Aperture position according to the height, which is found that when the aperture at the centre of the partition (case 13), the reduction in heat transfer is 16.7%, while when the aperture displaced to the upper surface (case 14), the reduction is 19% compared with the non partitioned enclosure.
4. Partition thickness (t), which is found that when t = 10 mm (case 4,5) the reduction in heat transfer is 17.2%, while when t = 150 mm (case 16) the reduction is 20.5% compared with the non partitioned enclosure.
5. Partition inclination (), which is found that the rate of heat transfer reduced with increasingas shown:
a. For = 30 toward the cold wall (case 22), the reduction in heat transfer is 18.2%.
b. For = 45 toward the cold wall (case 18), the reduction in heat transfer was 21.9%.
c. For = 60 toward the cold wall (case 20), the reduction in heat transfer is 30.2%.
d. For = 30 toward the hot wall (case 21), the reduction in heat transfer is 31.3%.
e. For = 45 toward the hot wall (case 17), the reduction in heat transfer is 40.7%.

f. For = 60 toward the hot wall (case 19), the reduction in heat transfer is 42.1%.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Feb 01 2015
Journal Name
Journal Of Engineering
Unit Price and Cost Estimation Equations through Items Percentage of Construction Works in a Desert Area
...Show More Authors

This research will cover different aspects of estimating process of construction work in a desert area. The inherent difficulties which accompany the cost estimating of the construction works in desert environment in a developing country, will stem from the limited information available, resources scarcity, low level of skilled workers, the prevailing severe weather conditions and many others, which definitely don't provide a fair, reliable and accurate estimation. This study tries to present unit price to estimate the cost in preliminary phase of a project.  Estimations are supported by developing mathematical equations based on the historical data of maintenance, new construction of managerial and school projects.

... Show More
View Publication Preview PDF
Publication Date
Tue Sep 05 2023
Journal Name
Iraqi Post Graduate Medical Journal.
Immunohistochemical Expression of Carbonic Anhydrase IX and PAX8 in Renal Cell Carcinoma: A Clinicopathological Correlation Study.
...Show More Authors

Publication Date
Thu Jul 31 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Fracture strength of laminate veneers using different restorative materials and techniques (A comparative in vitro stuy)
...Show More Authors

Background: Esthetic correction represents one of the clinical conditions that required the use of laminate veneers in premolars region. Aim of the study: The purpose of this study was to evaluate the fracture strength of the laminate veneers in maxillary first premolars, fabricated from either composite (direct and indirect techniques) or ceramic CAD/CAM blocks. Materials and Methods: Fifty sound human maxillary premolar teeth were used in this in vitro study. Teeth were divided randomly into one control group and four experimental groups of ten teeth each; Group A: Restored with direct composite veneer (Filtek Z250 XT), Group B: Restored with indirect composite veneers (Filtek Z250 XT), Group C: Restored with lithium disilicate ceramic CA

... Show More
View Publication Preview PDF
Publication Date
Sun Dec 16 2018
Journal Name
Al-academy
Alienation in Contemporary Sculpture between the Works of Anthony Caro and Tony Cragg (A Comparative Study)
...Show More Authors
  • The subject of this research is the study of the formal alienation of contemporary English sculpture, by comparing the most important sculptors of the new contemporary generation. This research problem is to look for the important factors in the formation of the contemporary sculptural structure of the exotic, and what is the mechanism of formation and output of these forms. The research seeks to explore (Alienation in contemporary sculpture between the works of Anthony Caro and Tony Cragg) in a comparative study. The importance of the research is to identify the concept of alien forms in contemporary British sculpture, especially in the cases of Anthony Caro and Tony Cragg that this research is considered a know

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Jan 16 2023
Journal Name
Iraqi National Journal Of Nursing Specialties
Dependence Severity, Locus of Control, and Readiness to Change in Male Alcoholic Clients: A Correlational Study
...Show More Authors

Objectives: To assess the level of dependence severity, locus of control, and readiness to change in male alcohol clients and measure the correlation between dependence with a locus of control and readiness to change.

Methodology: A descriptive correlational design was conducted in the substance use rehabilitation centers at psychiatric teaching hospitals in Baghdad city from November /2021 to May 2022. The instrument of the study was designed by using sociodemographic, the clinical characteristics of the client, the Short-form Alcohol Dependence Data Questionnaire (SADD), Drinking Related Internal-External Locus of Control Scale: (DRIE), and the Stages of Change Readiness and Treatment Eagerness Scale (SOCRATES). The data was co

... Show More
View Publication Preview PDF
Publication Date
Wed Dec 01 2021
Journal Name
Open Biology
Structure and in silico simulations of a cold-active esterase reveals its prime cold-adaptation mechanism
...Show More Authors

Here we determined the structure of a cold active family IV esterase (EstN7) cloned from Bacillus cohnii strain N1. EstN7 is a dimer with a classical α/β hydrolase fold. It has an acidic surface that is thought to play a role in cold-adaption by retaining solvation under changed water solvent entropy at lower temperatures. The conformation of the functionally important cap region is significantly different to EstN7's closest relatives, forming a bridge-like structure with reduced helical content providing greater access to the active site through more than one substrate access tunnel. However, dynamics do not appear to play a major role in cold adaption. Molecular dyn

... Show More
View Publication
Scopus (13)
Scopus
Publication Date
Wed Mar 29 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Development and in vitro Evaluation of Bioadhesive Vaginal Tablet using Econazole Nitrate as a Model Drug
...Show More Authors

         In this study, a bioadhesive dosage form of eoconazole nitrate for vaginal delivery was designed using a combination of bioadhesive polymers: Carbopol 941 p and sodium carboxymethylcellulose or methylcellulose in different ratios. The bioadhesive strength was evaluated by measuring the force required to detach the tablet from sheep vaginal mucosal membrane. It was found that the bioadhesive force was directly proportional to Carbopol 941 p content in the different formulae. The formulae were tested for their swelling behavior using agar gel plate method. The results showed that formulae containing a combination of Carbopol 941 p and sodium carboxymethylcellulose had greater swelling index

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Apr 27 2020
Journal Name
Journal Of Mechanics Of Continua And Mathematical Sciences
A COMPARISON OF TOPOLOGICAL KRIGING AND AREA TO POINT KRIGING FOR IRREGULAR DISTRICT AREA IN IRAQ
...Show More Authors

View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Sat Oct 01 2022
Journal Name
The Egyptian Journal Of Hospital Medicine
Study on Some Parameters and Anti-Rubella Igg in A Sample of Systemic Lupus Erythematosus Patients
...Show More Authors

View Publication
Scopus Crossref
Publication Date
Mon Oct 28 2019
Journal Name
Periodicals Of Engineering And Natural Sciences (pen)
Kinetic profile of silver and zinc oxide nanoparticles by intraperitoneal injection in mice , a comparative study
...Show More Authors

View Publication
Scopus (3)
Scopus Crossref