Preferred Language
Articles
/
joe-2995
DEVELOPING LAMINAR MIXED CONVECTION HEAT TRANSFER THROUGH VERTICAL CONCENTRIC ANNULI WITH ADIABATIC INNER CYLINDER
...Show More Authors

Theoretical and experimental investigations have been carried out on developing laminar
combined free and forced convection heat transfer in a vertical concentric annulus with uniformly
heated outer cylinder (constant heat flux) and adiabatic inner cylinder for both aiding and opposing
flows. The theoretical investigation involved a mathematical modeling and numerical solution for
two dimensional, symmetric, simultaneously developing laminar air flows was achieved. The
governing equations of motion (continuity, momentum and energy) are solved by using implicit
finite difference method and the Gauss elimination technique. The theoretical work covers heat flux
range from (200 to 1500) W/m2, Re range from 400 to 2000 and (1.36×105 ≤ Ra ≤ 1.1×107) with
radius ratio of 0.555 which is the same radius ratio used in the experimental part of this study and
Pr=0.7. The experimental work includes construct a rig consists essentially of an annulus with
uniformly heated outer cylinder and adiabatic inner cylinder to give clear insight into heat transfer
process and compare its results with that obtained in theoretical part, the range of the study are
(Re= 383, 724, 1000, 1500) and heat flux equal to (q =370, 422, 588, 980) W/m2. Numerical results
were represented by the temperature profile, axial velocity profile, outer surface temperature and
the distribution of local Nusselt number along the dimensionless axial distance. The velocity and
temperature profile results have revealed that the secondary flow created by natural convection have
significant effects on the heat transfer process. Results reveal also that the experimental local
Nusselt number along the annulus follows the same trend as present theoretical results with mean
difference 10.23 %.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sat Oct 23 2021
Journal Name
Indian Journal Of Ecology
Survey and Diagnosis Insects Associated with Fish Ponds
...Show More Authors

Publication Date
Fri Aug 05 2016
Journal Name
International Journal Of Advances In Scientific Research And Engineering
Image Encryption Using Modified AES with Bio-Chaotic
...Show More Authors

Due to the vast using of digital images and the fast evolution in computer science and especially the using of images in the social network.This lead to focus on securing these images and protect it against attackers, many techniques are proposed to achieve this goal. In this paper we proposed a new chaotic method to enhance AES (Advanced Encryption Standards) by eliminating Mix-Columns transformation to reduce time consuming and using palmprint biometric and Lorenz chaotic system to enhance authentication and security of the image, by using chaotic system that adds more sensitivity to the encryption system and authentication for the system.

View Publication Preview PDF
Publication Date
Thu Dec 30 2004
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Simulation of naturally Fractured Reservoirs with SimBest ll
...Show More Authors

View Publication Preview PDF
Publication Date
Mon Jan 01 2024
Journal Name
Journal Of Engineering
Strengthening of GFRP Reinforced Concrete Slabs with Openings
...Show More Authors

Using fiber-reinforced polymer (FRP) could effectively improve the strength and endurance of reinforced concrete (RC) constructions. This study evaluated the flexural behavior of one-way concrete slabs with openings reinforced with glass fiber-reinforced polymers (GFRP) bars. It strengthened using carbon fiber-reinforced polymer (CFRP) sheets around the openings. The experimental program of this study is adopted by casting and testing four one-way concrete slabs with dimensions of (150*750*2650) mm. These slabs are divided into two groups based on whether they were strengthened or un-strengthened. For each group, two different openings (either one rectangular or two square) measured 250*500 mm and 250*250 mm, respective

... Show More
View Publication Preview PDF
Crossref (6)
Crossref
Publication Date
Sat Aug 01 2020
Journal Name
Key Engineering Materials
Performance of Reinforced Concrete Beams with Multiple Openings
...Show More Authors

The present investigation focuses on the response of simply supported reinforced concrete rectangular-section beams with multiple openings of different sizes, numbers, and geometrical configurations. The advantages of the reinforcement concrete beams with multiple opening are mainly, practical benefit including decreasing the floor heights due to passage of the utilities through the beam rather than the passage beneath it, and constructional benefit that includes the reduction of the self-weight of structure resulting due to the reduction of the dead load that achieves economic design. To optimize beam self-weight with its ultimate resistance capacity, ten reinforced concrete beams having a length, width, and depth of 2700, 100, and

... Show More
View Publication Preview PDF
Scopus (5)
Crossref (5)
Scopus Crossref
Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
Variational Formulation with Deviating Arguments of Movable boundaries
...Show More Authors

In this paper, we study, in details the derivation of the variational formulation corresponding to functional with deviating arguments corresponding to movable boundaries. Natural or transversility conditions are also derived, as well as, the Eulers equation. Example has been taken to explain how to apply natural boundary conditions to find extremal of this functional.

View Publication Preview PDF
Publication Date
Sat Oct 01 2011
Journal Name
Iraqi Journal Of Physics
Preparation of nano-microfibers with a different polymers
...Show More Authors

Abstract: In this research, nanofibers have been prepared by using an electrospinning method. Three types of polymer (PVA, VC, PMMA) have been used with different concentration. The applied voltage and the gap length were changed. It was observed that VC is the best polymer than the other types of polymers.

Preview PDF
Publication Date
Tue Jan 27 2026
Journal Name
Iraqi Journal Of Mechanical And Material Engineering
WAKE ROLL-UP BEHIND WINGS WITH GROUND EFFECT
...Show More Authors

A numerical method for the calculation of the three-dimensional wake rollup behind symmetric wings with ground effect and its aerodynamic characteristics for steady low subsonic flow have been developed. A non-planar quadrilateral vortex-ring method with vortex wake relaxation iterative scheme for lifting surfaces is obtained. A computer program was build to treat wings with breaks, span wise trailing edge flaps, local dihedral angle, camber, twist and ground effect. Forces and moments are obtained from vector product of local velocity and vortex strength multiplied by density. The program has been validated for a number of configurations for which experimental data is available. Good agreement has been obtained for these configurations. Al

... Show More
View Publication
Publication Date
Sat Oct 01 2011
Journal Name
Iraqi Journal Of Physics
Preparation of nano-microfibers with a different polymers
...Show More Authors

In this research, nanofibers have been prepared by using an electrospinning method. Three types of polymer (PVA, VC, PMMA) have been used with different concentration. The applied voltage and the gap length were changed. It was observed that VC is the best polymer than the other types of polymers.

View Publication Preview PDF
Publication Date
Thu Jan 01 2015
Journal Name
Ibn Al-haitham Jour. For Pure & Appl. Sci
Swelling Behavior of Cross-link PVA with Glutaraldehyde
...Show More Authors

The polymeric hydrogels composed of poly vinyl alcohol (m.wt 72000) and glutaraldehyde(5%,8% and 10%) , have been thermally prepared for the purpose of studying their swelling and drug release behavior . The swelling ratio was measured for all the hydrogel samples at 37°C, in three different media pH (1.2, 4.7 and 6.8) as a function of time. The results show that the maximum swelling ratios were arranged as follows :pH =6.8 > pH =4.7 > pH =1.2 hydrogels cross linked PVA showed a typical pH responsive behavior such as high pH has maximum swelling while low pH shows minimum swelling.