Preferred Language
Articles
/
alkej-88
Efficiency Enhancement of a Dual-axis Solar PV Panel Tracker Using Water-Flow Double Glazing Technique
...Show More Authors

The fall angle of sun rays on the surface of a photovoltaic PV panel and its temperature is negatively affecting the panel electrical energy produced and efficiency. The fall angle problem was commonly solved by using a dual-axis solar tracker that continually maintains the panel orthogonally positioning to the sun rays all day long. This leads to maximum absorption for solar radiation necessary to produce maximum amount of energy and maintain high level of electrical efficiency. To solve the PV panel temperature problem, a Water-Flow Double Glazing WFDG technique has been introduced as a new cooling tool to reduce the panel temperature. In this paper, an integration design of the water glazing system with a dual-axis tracker has been accomplished and experimentally tested in order to enhance the PV panel efficiency, especially at hot climates. The proposed glazing system can simultaneously perform two functions, firstly, working as a cooling tool for reducing the stored heat in the PV panel during its work and secondly as an optical filter for sun light spectrum. Optimum design factors with their levels for the glazing system were calculated according to Taguchi method. Test experiments were carried out in Baghdad city on the 20th and 21st July 2016 on the tracker with and without using the WFDG system. The obtained results show that, the PV panel temperature with using the WFDG system was significantly dropped by 44% and its efficiency increased maximally by 36.6% at solar irradiance of 1213W/m2 as compared with conventional one.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed Dec 01 2021
Journal Name
Journal Of Engineering
Review of the Kriging Technique Applications to Groundwater Quality
...Show More Authors

Kriging, a geostatistical technique, has been used for many years to evaluate groundwater quality. The best estimation data for unsampled points were determined by using this method depending on measured variables for an area. The groundwater contaminants assessment worldwide was found through many kriging methods. The present paper shows a review of the most known methods of kriging that were used in estimating and mapping the groundwater quality. Indicator kriging, simple kriging, cokriging, ordinary kriging, disjunctive kriging and lognormal kriging are the most used techniques. In addition, the concept of the disjunctive kriging method was explained in this work to be easily understood.

View Publication Preview PDF
Crossref (4)
Crossref
Publication Date
Mon Jan 01 2024
Journal Name
Baghdad Science Journal
Semi-Analytical Assessment of Magneto-Hydrodynamic Nano-Fluid Flow Jeffrey- Hamel Problem
...Show More Authors

In this paper, analyzing the non-dimensional Magnesium-hydrodynamics problem Using nanoparticles in Jeffrey-Hamel flow (JHF) has been studied. The fundamental equations for this issue are reduced to a three-order ordinary differential equation. The current project investigated the effect of the angles between the plates, Reynolds number, nanoparticles volume fraction parameter, and magnetic number on the velocity distribution by using analytical technique known as a perturbation iteration scheme (PIS). The effect of these parameters is similar in the converging and diverging channels except magnetic number that it is different in the divergent channel. Furthermore, the resulting solutions with good convergence and high accuracy for the d

... Show More
View Publication Preview PDF
Scopus (2)
Scopus Crossref
Publication Date
Wed Jan 01 2014
Journal Name
Advances In Mechanical Engineering
Experimental and Numerical Investigations of Heat Transfer Characteristics for Impinging Swirl Flow
...Show More Authors

This paper reports experimental and computational fluid dynamics (CFD) modelling studies to investigate the effect of the swirl intensity on the heat transfer characteristics of conventional and swirl impingement air jets at a constant nozzle-to-plate distance ( L = 2 D). The experiments were performed using classical twisted tape inserts in a nozzle jet with three twist ratios ( y = 2.93, 3.91, and 4.89) and Reynolds numbers that varied from 4000 to 16000. The results indicate that the radial uniformity of Nusselt number (Nu) of swirl impingement air jets (SIJ) depended on the values of the swirl intensity and the air Reynolds number. The results also revealed that the SIJ that was fitted with an insert of y = 4.89, which correspo

... Show More
View Publication
Scopus (16)
Crossref (10)
Scopus Clarivate Crossref
Publication Date
Sun Jan 01 2017
Journal Name
Journal Of Engineering
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

... Show More
View Publication Preview PDF
Publication Date
Thu Oct 31 2013
Journal Name
Al-khwarizmi Engineering Journal
Theoretical and Practical Investigation of Blood Flow through Stenosed Coronary Lad Artery
...Show More Authors

Atherosclerosis is the most common causes of vascular diseases and it is associated with a restriction in the lumen of blood vessels. So; the study of blood flow in arteries is very important to understand the relation between hemodynamic characteristics of blood flow and the occurrence of atherosclerosis.

looking for the physical factors and correlations that explain the phenomena of existence the atherosclerosis disease in the proximal site of LAD artery in some people rather than others is achieved in this study by analysis data from coronary angiography as well as estimating the blood velocity from coronary angiography scans without having a required data on velocity by using some mathematical equations and physical laws. Fif

... Show More
View Publication Preview PDF
Publication Date
Thu Feb 06 2020
Journal Name
Scientific Reports
Waste foundry sand/MgFe-layered double hydroxides composite material for efficient removal of Congo red dye from aqueous solution
...Show More Authors
Abstract<p>We aimed to obtain magnesium/iron (Mg/Fe)-layered double hydroxides (LDHs) nanoparticles-immobilized on waste foundry sand-a byproduct of the metal casting industry. XRD and FT-IR tests were applied to characterize the prepared sorbent. The results revealed that a new peak reflected LDHs nanoparticles. In addition, SEM-EDS mapping confirmed that the coating process was appropriate. Sorption tests for the interaction of this sorbent with an aqueous solution contaminated with Congo red dye revealed the efficacy of this material where the maximum adsorption capacity reached approximately 9127.08 mg/g. The pseudo-first-order and pseudo-second-order kinetic models helped to describe the sorption measure</p> ... Show More
Scopus (193)
Crossref (129)
Scopus Clarivate Crossref
Publication Date
Thu Feb 02 2012
Journal Name
Education College Journal/al-mustansiriyah University
On Significance Testimator in Pareto Distribution Via Shrinkage Technique
...Show More Authors

In this paper, preliminary test Shrinkage estimator have been considered for estimating the shape parameter α of pareto distribution when the scale parameter equal to the smallest loss and when a prior estimate α0 of α is available as initial value from the past experiences or from quaintance cases. The proposed estimator is shown to have a smaller mean squared error in a region around α0 when comparison with usual and existing estimators.

Preview PDF
Publication Date
Mon Jan 01 2007
Journal Name
Journal Of Educational And Psychological Researches
Evaluating the Professional Efficiency of Primary School Teachers in Teaching Rafidain English Course for Iraq, Book I
...Show More Authors

      Teaching techniques are the vehicles, which are used by teachers to help pupils learn and gain experiences and create positive classroom activities, as much as these techniques are varied, they lead to successful and fruitful learning in the foreign language. They help teachers achieve their objectives (Asowrth, 1985: 124).

    The English language teacher's work is an active and purposeful one when he can plan carefully and frequently make the necessary changes in the contents and methods of teaching programme to fit the interest and needs of pupils. It seems that the majority of primary English teachers' interests does not go far in planning their work, and do not understand which o

... Show More
View Publication Preview PDF
Publication Date
Wed Aug 03 2022
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The pioneering trend in managing health institutions and its impact on improving the quality of services : A case study in some institutions of the Iraqi Ministry of Health
...Show More Authors

This study seeks to identify the role that the leadership trend plays in the management of health institutions in Iraq and its impact on improving the quality of the health service provided by analyzing some opinions of affiliates working in the Iraqi health sector where a survey list was used as a main tool for collecting primary data, as it was subjected to this analysis ( 60) of the medical staff, of whom (40) are doctors and (20) are affiliated with the rank of assistant physician, and (60) members of the administrative cadre have undergone their various job ranks and administrative specializations (department manager, auditor, observer, accountant, statistician, secretary). Reliance on statistical software (spss) in data ana

... Show More
View Publication Preview PDF
Publication Date
Fri Mar 30 2007
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Testing of Drinking Water Reservoirs Coating
...Show More Authors

The present study refers to a ready-made three components epoxy based paint made by the Modern Paints Industries Company (Al-Za'farania, Baghdad) subjected to several tests in order to improve its specifications by optimizing the application conditions. The paint components are under the trade names: Resin (D-5547), Hardener (H-1457) and Thinner (P-851). The paint is used for painting drinking water reservoirs from inside.

View Publication Preview PDF