Preferred Language
Articles
/
joe-92
Effect of Air Bubbles on Heat Transfer Coefficient in Turbulent Convection Flow
...Show More Authors

Experimental and numerical studies have been conducted for the effect of injected air bubbles on the heat transfer coefficient through the water flow in a vertical pipe under the influence of uniform heat flux. The investigated parameters were water flow rate of (10, 14 and 18) lit/min, air flow rate of (1.5, 3 and 4) lit/min for subjected heat fluxes of (27264, 36316 and 45398) W/m2. The energy, momentum and continuity equations were solved numerically to describe the motion of flow. Turbulence models k-ε was implemented. The mathematical model is using a CFD code Fluent (Ansys15). The water was used as continuous phase while the air was represented as dispersed. phase. The experimental work includes design, build and instrument a test rig for that purpose. A
circular vertical copper pipe test section of (length=0.7m, diameter= 0.05m, thickness= 1.5mm) is . designed and constructed, heated by an electrical heater fixed on its outer surface. Water . temperature at inlet is kept constant at (32°C). Water inlet and outlet temperatures, as well as radial temperature distribution within the pipe at seven sections along it between pipe surface and its center are measured. The results revealed that the secondary flow created by air bubbles have
significant effects on heat transfer enhancement and temperature profile. It is observed, that averaged Nusselt number enhancement for low heat flux of 27264 W/m2 and 4 lit/min air bubbles was 33.3 % and 23% in numerical and experimental, respectively.

 
 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Jun 01 2023
Journal Name
Journal Of Engineering
Discharge Coefficient of Contracted Rectangular Sharp-Crested Weirs, an Experimental Study
...Show More Authors

An experimental study is made here to investigate the discharge coefficient for contracted rectangular Sharp crested weirs. Three Models are used, each with different weir width to flume width ratios (0.333, 0.5, and 0.666). The experimental work is conducted in a standard flume with high-precision head and flow measuring devices. Results are used to find a dimensionless equation for the discharge coefficient variation with geometrical, flow, and fluid properties. These are the ratio of the total head to the weir height, the ratio of the contracted weir width to the flume width, the ratio of the total head to the contracted width, and Reynolds and Weber numbers. Results show that the relationship between the discharge co

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Jul 01 2019
Journal Name
Iop Conference Series: Materials Science And Engineering
Calculating heterogeneity of Majnoon Field/Hartha Reservoir using Lorenz Coefficient method
...Show More Authors
Abstract<p>One of the principle concepts to understand any hydrocarbon field is the heterogeneity scale; This becomes particularly challenging in supergiant oil fields with medium to low lateral connectivity and carbonate reservoir rocks.</p><p>The main objectives of this study is to quantify the value of the heterogeneity for any well in question, and propagate it to the full reservoir. This is a quite useful specifically prior to conducting detailed water flooding or full field development studies and work, in order to be prepared for a proper design and exploitation requirements that fit with the level of heterogeneity of this formation.</p><jats></jats> ... Show More
View Publication
Scopus (1)
Crossref (1)
Scopus Crossref
Publication Date
Sat Dec 24 2022
Journal Name
Wasit Journal Of Pure Sciences
Synthesis of the integer FIR filters with short coefficient word length
...Show More Authors

The integer simulation and development finite impulse response (FIR) filters taking into account the possibilities of their realization on digital integer platforms are considered. The problem statement and solution of multifunctional synthesis of digital FIR filters such a problem on the basis of the numerical methods of integer nonlinear mathematical programming are given. As an several examples, the problem solution of synthesis FIR-filters with short coefficient word length  has been given. The analysis of their characteristics is resulted. The paper discusses issues of modeling and synthesis of digital FIR filters with provision for the possibilities of their implementation on digital platforms with integer computation arithme

... Show More
View Publication
Crossref
Publication Date
Sun Apr 30 2023
Journal Name
Sabrao Journal Of Breeding And Genetics
PATH COEFFICIENT ANALYSES OF INTRODUCED RICE VARIETIES UNDER DIFFERENT PLANTING DISTANCES
...Show More Authors

Five rice (Oryza sativa L.) cultivars (N22, Amber, Moroberekan, Kinandang Patong, and Azucena) underwent path coefficient analysis across three plant spacings (15 cm × 15 cm, 20 cm × 20 cm, and 25 cm× 25 cm) in the summer of 2017 at the College of Agricultural Engineering Sciences, University of Baghdad, Al-Jadriya, Iraq. The experiment proceeded in a randomized complete block design (RCBD) with a split-plot arrangement and three replications. The main plots included three planting distances, and the subplot comprised five varieties. The traits studied were plant height, flag leaf area, number of tillers, panicle number, length and branches, grains per panicle, 1000-grain weight, and the percentage of unfilled grains. The results

... Show More
View Publication
Scopus (7)
Crossref (3)
Scopus Clarivate Crossref
Publication Date
Thu Apr 25 2019
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
FLOW INJECTION ANALYSIS AND SPECTROPHOTOMETRIC DETERMINATION OF NIFEDIPINEIN PHARMACEUTICAL FORMULATION: FLOW INJECTION ANALYSIS AND SPECTROPHOTOMETRIC DETERMINATION OF NIFEDIPINEIN PHARMACEUTICAL FORMULATION
...Show More Authors

A new simple and sensitive spectrophotometric method is described for quantification of Nifedipine (NIF) and their pharmaceutical formulation. The selective method was performed by the reduction of NIF nitro group to yield primary amino group using zinc powder with hydrochloric acid. The produced aromatic amine was submitted to oxidative coupling reaction with pyrocatechol and ammonium ceric nitrate to form orange color product measured spectrophotometrically with maximum absorption at 467nm. The product was determined through flow injection analysis (FIA) system and all the chemical and physical parameters were optimized. The concentration range from 5.0 to 140.0 μg.mL-1 was obeyed Beer’s law with a limit of detection and quantitatio

... Show More
View Publication Preview PDF
Publication Date
Mon Feb 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
International variables and their impact on the flow of foreign direct investment in Gulf Cooperation Council (GCC)
...Show More Authors

Abstract:

The six Arab Gulf states (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, UAE) play a vital role, especially with its geographical location and natural  resources (oil and gas) as well as other cultural and civilizational elements, in achieving  global economic balance and more specifically global energy security, naturally  because of  these countries have a comparative advantage in the field of fossil energy (oil and gas), thus this sector becomes more attractive for local and international investments alike. Being  the energy sector a leader sector in the economic development process, and the basic factor to achieve savings and financial surpluses in thes

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Mar 01 2020
Journal Name
Journal Of Engineering
Thermal Performance Analysis of Compact Heat Exchangers for Thermoelectric Generators
...Show More Authors

The efficiency of internal combustion engines (ICE) is usually about thirty percent of the total energy of the fuel. The residual energy is lost in the exhaust gas, the lubrication, and the cooling water in the radiators. Recently much of the researcher’s efforts have focused on taking advantage of wasted energy of the exhaust gas. Using a thermoelectric generator (TEG) is one of the promising ways. However, TEG depends entirely on the temperature difference, which may be offered by the exhaust muffler. An experimental test has been conducted to study the thermal performance of a different muffler internal design. The researchers resort to the use of lost energy in an ICE using TEG, which is one of the ways to take adv

... Show More
View Publication Preview PDF
Crossref (3)
Crossref
Publication Date
Fri Apr 01 2022
Journal Name
Journal Of Engineering
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 numb

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Mar 20 2019
Journal Name
Al-khwarizmi Engineering Journal
Natural-Convection Phenomenon from a Finned Heated Vertical Tube: Experimental Analysis
...Show More Authors

       In this work, an experimental analysis is made to predict the thermal performance of the natural-convection phenomenon from a heated vertical externally finned-tube to surrounding air through an open-ended enclosure. Two different configurations of longitudinal rectangular fin namely, continuous and interrupted are utilized with constant thickness, different numbers, and different heights are extended radially on the outer surface of a heated tube. The tube is heated electrically from inner surface with five varied power input magnitudes. The effect of fins configuration, fins number, fins height, and heat flux of the inner tube surface on the thermal performance of natural c

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Jul 20 2025
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
An Article Review: Charge-Transfer of Polyenes and Carotenes
...Show More Authors

     When an electron moves from one atom or molecule to another, a charge-transfer complex is formed. The other objects must be able to accept these electrons, and one entity must have free electrons or a tendency to donate them. This resembles an internal oxidation-reduction reaction more. This research aims to shed light on charge transfer complexes formed by polyenes and carotenes, which act as electron-donating molecules due to their alternating double and single bonds. This allows them to create such complexes when interacting with organic molecules that lack electrons. These complexes exhibited distinctive optical and physicochemical properties, enabling them to be adapted for a wide range of applications. In addition, th

... Show More
View Publication Preview PDF
Crossref