Preferred Language
Articles
/
joe-1531
Numerical study of natural convection in an annulus between two concentric cylinders provided with metal foam fins
...Show More Authors

Natural convection in an annular space provided with metal foam fins attached to the inner cylinder is studied numerically. The metal foam fins made of copper were inserted in different axial sections with three fins in each section. The temperature of the inner cylinder is kept constant while the annular outer surface is adiabatic. The thickness effect of the inner pipe wall was considered. Naiver Stokes equation with Boussinesq approximation is used for the fluid regime while Brinkman-Forchheimer Darcy model is used for metal foam. In addition, the local thermal non-equilibrium condition in the energy equation of the porous media is presumed. The effect of Rayleigh number and number of foam fins in the axial direction, on fluid flow and heat transfer characteristics, were examined. The current model was valid with the available published results and good agreement is noticed. Results showed that as the Rayleigh number increases the dominated of convection mode increases and average Nusselt increases. It was found that at Rayleigh of 106 Nusselt reached its higher value which is 4.6 for the case of adding seven axial metal foams. A comparison between adding foam fins and copper fins was established for a range of Rayleigh numbers between 104 and 106. It showed a good enhancement in Nusselt number and the greatest enhancement percentage was 45.9% at Rayleigh equal 106 for the case of using seven sections of foam fins.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Dec 01 2015
Journal Name
Journal Of Economics And Administrative Sciences
Organizational Red Tapes and their Reflections on Entrepreneurial Orientation: an Exploratory Study of a Sample of Employees in Some Organizations in the Province of Ninewah
...Show More Authors

Organizations adopt a number of procedures and instructions in their field of activities in order to aid their resources development   and energies to serve their entrepreneurial orientations. This calls for preparing a range of mechanisms to mitigate the strictness and complexity of procedures. The ambiguity and severe  complexity  of procedures means acknowledging the loss in energy and this in turn  impedes the hopes while in the same time weakens the  enthusiasm in these organizations and an impedes the possibility to achieve continues innovation, thereby losing opportunities to the level of surrender to the risks and  assuming them to be unconquered obstacles.

There

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Thu Dec 15 2022
Journal Name
Engineering, Technology & Applied Science Research
Numerical Modeling of a Pile Group Subjected to Seismic Loading Using the Hypoplasticity Model
...Show More Authors

Various simple and complicated models have been utilized to simulate the stress-strain behavior of the soil. These models are used in Finite Element Modeling (FEM) for geotechnical engineering applications and analysis of dynamic soil-structure interaction problems. These models either can't adequately describe some features, such as the strain-softening of dense sand, or they require several parameters that are difficult to gather by conventional laboratory testing. Furthermore, soils are not completely linearly elastic and perfectly plastic for the whole range of loads. Soil behavior is quite difficult to comprehend and exhibits a variety of behaviors under various circumstances. As a result, a more realistic constitutive model is

... Show More
View Publication
Crossref (6)
Crossref
Publication Date
Thu Dec 15 2022
Journal Name
Engineering, Technology & Applied Science Research (etasr)
Numerical Modeling of a Pile Group Subjected to Seismic Loading Using the Hypoplasticity Model
...Show More Authors

Various simple and complicated models have been utilized to simulate the stress-strain behavior of the soil. These models are used in Finite Element Modeling (FEM) for geotechnical engineering applications and analysis of dynamic soil-structure interaction problems. These models either can't adequately describe some features, such as the strain-softening of dense sand, or they require several parameters that are difficult to gather by conventional laboratory testing. Furthermore, soils are not completely linearly elastic and perfectly plastic for the whole range of loads. Soil behavior is quite difficult to comprehend and exhibits a variety of behaviors under various circumstances. As a result, a more realistic constitutive model is

... Show More
View Publication Preview PDF
Scopus (6)
Crossref (6)
Scopus Clarivate Crossref
Publication Date
Sun May 21 2023
Journal Name
Fire
Experimental and Numerical Behavior of Encased Pultruded GFRP Beams under Elevated and Ambient Temperatures
...Show More Authors

In this research, experimental and numerical studies were carried out to investigate the performance of encased glass-fiber-reinforced polymer (GFRP) beams under fire. The test specimens were divided into two peer groups to be tested under the effect of ambient and elevated temperatures. The first group was statically tested to investigate the monotonic behavior of the specimens. The second group was exposed to fire loading first and then statically tested to explore the residual behavior of the burned specimens. Adding shear connectors and web stiffeners to the GFRP beam was the main parameter in this investigation. Moreover, service loads were applied to the tested beams during the fire. Utilizing shear connectors, web stiffeners,

... Show More
Scopus (27)
Crossref (28)
Scopus Clarivate Crossref
Publication Date
Sun May 21 2023
Journal Name
Fire
Experimental and Numerical Behavior of Encased Pultruded GFRP Beams under Elevated and Ambient Temperatures
...Show More Authors

In this research, experimental and numerical studies were carried out to investigate the performance of encased glass-fiber-reinforced polymer (GFRP) beams under fire. The test specimens were divided into two peer groups to be tested under the effect of ambient and elevated temperatures. The first group was statically tested to investigate the monotonic behavior of the specimens. The second group was exposed to fire loading first and then statically tested to explore the residual behavior of the burned specimens. Adding shear connectors and web stiffeners to the GFRP beam was the main parameter in this investigation. Moreover, service loads were applied to the tested beams during the fire. Utilizing shear connectors, web stiffeners,

... Show More
View Publication
Scopus (27)
Crossref (28)
Scopus Clarivate Crossref
Publication Date
Tue Feb 01 2022
Journal Name
Journal Of Structural Engineering
Experimental and Numerical Evaluation of a Welded Demountable Shear Connector through Horizontal Pushout Tests
...Show More Authors

A novel welded demountable shear connector for sustainable steel-concrete composite structures is proposed. The proposed connector consists of a grout-filled steel tube bolted to a compatible partially threaded stud, which is welded on a steel section. This connector allows for an easy deconstruction at the end of the service life of a building, promoting the reuse of both the concrete slabs and the steel sections. This paper presents the experimental evaluation of the structural behavior of the proposed connector using a horizontal pushout test arrangement. The effects of various parameters, including the tube thickness, the presence of grout infill, and the concrete slab compressive strength, were assessed. A nonlinear finite element mode

... Show More
View Publication
Scopus (24)
Crossref (16)
Scopus Clarivate Crossref
Publication Date
Wed Sep 01 2021
Journal Name
Baghdad Science Journal
New Method for Estimation Mebeverine Hydrochloride Drugs Preparation by a New Analyser: Ayah 6S.X1(WSLEDs)-T.- Two Solar Cells Complied with C.F.I.A
...Show More Authors

A sensitivity-turbidimetric method at (0-180o) was used for detn. of mebeverine in drugs by two solar cell and six source  with C.F.I.A.. The method was based on the formation  of  ion pair for the pinkish banana color  precipitate by the reaction of Mebeverine hydrochloride with Phosphotungstic acid. Turbidity was measured via the reflection of incident light that collides on the surface particles of   precipitated at 0-180o. All variables were optimized. The linearity ranged of Mebeverine hydrochloride was 0.05-12.5mmol.L-1, the L.D. (S/N= 3)(3SB) was 521.92 ng/sample depending on dilution for the minimum concentration , with correlation coefficient r = 0.9966while was R.S.D%

... Show More
View Publication Preview PDF
Scopus (8)
Crossref (6)
Scopus Clarivate Crossref
Publication Date
Sat Feb 21 2026
Journal Name
Journal Of Baghdad College Of Dentistry
The effect of plasma treatment on shear bond strength of soft denture liner with two different types of denture base material (heat cure and light cure)
...Show More Authors

Background: In this study we evaluate the effect of plasma treatment (oxygen and argon) gas in two different exposure times on the surface of heat cure and light cure acrylic resin. Materials and method: 100 specimens of heat cure and light cure acrylic resin were fabricated. The measurements of the samples were (75mm, 25mm and 4.5mm) length, width and depth respectively with stopper of 3mm depth. Two types of gas used oxygen and argon in (5,10) min by using (DC-glow discharge plasma device) then we apply cold cure soft lining material, with the help of Instron machine we test the shear stress value. Results: A highly significant effect after argon and oxygen gases treatment in both 5 and 10 min exposure times on shear bond strength to soft

... Show More
View Publication Preview PDF
Publication Date
Wed Mar 29 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Evaluation of the Relation between Asthma, Obesity and Leptin Level in Iraqi Asthmatic Patients and the Main Risk Factors that are Associated with Leptin Level
...Show More Authors

This study tries to clear the correlation and association between asthma, obesity and leptin levels. Also it will work to indicate the main risk factors which play role in the elevation of leptin level within asthmatic patients.  This is a case control study conducted on (38) asthmatic patients and (20) healthy control who were closely similar by age, gender and BMI. The main statistical tests used were student t test, linear regression test and correlation test. Significance was set at P < 0.05. Sampling method used for this study was convenience sampling method.  The main results of this study show a significant association and positive correlation between age (old age  â‰¥ 40 ye

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sat Feb 21 2026
Journal Name
Journal Of Baghdad College Of Dentistry
The Effect of Plasma Treatment on Shear Bond Strength of High Impact Acrylic Resin Denture Base Lined with Two Types of Soft Lining Materials after Immersion in Distilled Water and Denture Cleanser
...Show More Authors

Background: In dentistry, dentist takes the advantages of soft lining materials due to the viscoelastic properties. The major problem is the adhesion of the soft liner with the denture base material. Materials and Methods: Heat cured of high impact acrylic resin specimens prepared with dimensions 75x13x13mm for shear bond strength test, soft lining material (Refit and Mollosil) with a 3-mm thickness and used to join each two acrylic blocks. Also four specimens with the same previous dimensions utilized for chemical and physical surface analysis. The specimens grouped as control (without plasma) and experiment (with oxygen plasma) treated high impact acrylic specimens. Results: Plasma treatment increased the shear bond strength for both Refi

... Show More
View Publication Preview PDF