Preferred Language
Articles
/
alkej-320
Experimental and Numerical Study of Collector Geometry Effect on Solar Chimney Performance
...Show More Authors

There have been many advances in the solar chimney power plant  since 1930 and the first pilot work was built in Spain (Manzanares) that produced 50 KW. The solar chimney power plant is considered of a clean power generation that needs to be investigated  to enhance the performance by studying the effect of changing the area of passage of air to enhance the velocity towards the chimney to maximize design velocity. In this experimental and numerical study, the reduction area of solar collector was investigated. The reduction area that mean changing the height of glass cover from the absorbing plate (h1=3.8cm, h2=2.6cm and h3=1.28cm). The numerical study was performed using ANSYS Fluent software package (version 14.0) to solve governing equations. The aim of this work was to study the effect of change the height of reduction area to the design velocity (velocity move the blade of turbine at inlet in the chimney). The results showed that the third height (h3=1.28cm) gives the best result because when decreasing the height between the glass cover and absorbing plate, the area between them decreased and the design velocity increased then the efficiency of solar chimney model was increased.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sat Oct 16 2021
Journal Name
Iraqi Journal Of Physics
Numerical analysis of molecules intersystem crossing effect on a passively Q- switched laser pulse characteristics
...Show More Authors

The effect of molecules intersystem crossing (Kisc) on characteristics
(energy and duration) of a Passive Q- switched Laser Pulse has been
studied by mathematical description (rate equations model) for
temporal performance of which was used as a saturable absorber
material (passive switch) with laser. The study shows that the energy
and duration pulse are decreasing while the molecules intersystem
crossing into saturable absorber energy levels is increasing.

View Publication Preview PDF
Publication Date
Sat Oct 16 2021
Journal Name
Energies
Performance Analysis of a Solar Cooling System with Equal and Unequal Adsorption/Desorption Operating Time
...Show More Authors

In solar-thermal adsorption/desorption processes, it is not always possible to preserve equal operating times for the adsorption/desorption modes due to the fluctuating supply nature of the source which largely affects the system’s operating conditions. This paper seeks to examine the impact of adopting unequal adsorption/desorption times on the entire cooling performance of solar adsorption systems. A cooling system with silica gel–water as adsorbent-adsorbate pair has been built and tested under the climatic condition of Iraq. A mathematical model has been established to predict the system performance, and the results are successfully validated via the experimental findings. The results show that, the system can be operational

... Show More
View Publication
Scopus (11)
Crossref (11)
Scopus Clarivate Crossref
Publication Date
Sat Dec 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
تقييم إداء السياسة النقدية في العراق وأثرها في التضخم دراسة تحليلية للمدة من (1980- 2003)
...Show More Authors

تلعب السياسة النقدية دوراً فاعلاً ومتميزاً في تحقيق معدلات نمو عالية وتحقيق الاستقرار والتوازن الاقتصادي وبالاخص الحد من ظاهرة التضخم.

يمكن حصر اهداف السياسة النقدية في الدول النامية والعربية خصوصاً من خلال التعرف على الاغراض المنصوص عليها في التشريعات وتشمل (تحقيق استقرار نقدي، المحافظة على قيمة العملة، تشجيع النمو الاقتصادي، تطوير الاسواق المالية والنقدية، استقرار الاسعار، تحقيق ال

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Mon Nov 26 2018
Journal Name
Al-khwarizmi Engineering Journal
Study the Effect of Different Percentages of Natural (Orange Peels and Date Seeds) and Industrial Materials (Carbon and Silica) on the Mechanical and Thermal Properties of Polymeric Reinforced Composites
...Show More Authors

Mechanical and thermal properties of composites, consisted of unsaturated polyester resin, reinforced by different kinds of natural materials (Orange peels and Date seeds) and industrial materials (carbon and silica) with particle size 98 µm were studied. Various weight ratios, 5, 10, and 15 wt. % of natural and industrial materials have been infused into polyester. Tensile, three-point bending and thermal conductivity tests were conducted for the unfilled polyester, natural and industrial composite to identify the weight ratio effect on the properties of materials. The results indicated that when the weight ratio for polyester with date seeds increased from 10% to 15%, the maximum Young’s modulus decreased by 54%. When the weight rat

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Mar 13 2019
Journal Name
Al-khwarizmi Engineering Journal
Transient Behavior Analysis for Solar Energy Storage in PCM-CFM Material Using Equivalent Heat Capacity Method as Storage Model
...Show More Authors

A paraffin wax and copper foam matrix were used as a thermal energy storage material in the double passes air solar chimney (SC) collector to get ventilation effect through daytime and after sunset. Air SC collector was installed in the south wall of an insulated test room and tested with different working angles (30o, 45o and 60o). Different SC types were used; single pass, double passes flat plate collector and double pass thermal energy storage box collector (TESB). A computational model based on the finite volume method for transient tw dimensional domains was carried out to describe the heat transfer and storage in the thermal energy storage material of collector. Also, equivalent specific heat metho

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Wed Sep 09 2015
Journal Name
Elixir
Effect Tiers Pressure and Speeds tractor on Performance Chisel and Disc Plows
...Show More Authors

Field experiment conducted to measured Slippage, Effective field capacity, Field Efficiency, Soil Volume Disturbed and Specific Productivity Tillage in silt clay loam soil with depth 18 cm in Baghdad- Iraq. Split – split plot design under randomized complete block design with three replications using Least Significant Design 5 % was used. Three factor used in this experiment included Two types of plows included Chisel and Disk plows which represented main plot , Three Tires Inflation Pressure was second factor included 1.1 ,1.8 and 2.7 Bar, and Three forward speeds of the tillage was third factor included 2.35 , 4.25 and 6.50 km/hr. Result show chisel plow recorded best parameters performance

Publication Date
Sun Dec 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
Analytical study on the implications of the GATS Agreement and its implications on the Egyptian banking sector
...Show More Authors

International trade in services is becoming increasingly important as it is an economic activity that deals with invisible trade, which has become increasingly important in the balance of international trade. The establishment of the WTO is a starting point in international trade relations. It is responsible for all aspects of international trade, , And in view of the continued increase in international trade in services, the need for more internationally recognized rules has become more urgent, especially as it has been increasingly proven that the traditional framework of public services is inadequate to operate some of the most dynamic and innovative sectors of the economy. (GATS) to be the regulatory framework for this sector

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Dec 30 2021
Journal Name
College Of Islamic Sciences
Controls Scanning on the slippers: a study fiqhiat Comparison
...Show More Authors

 

 

Controls Scanning on the slippers a study fiqhiat Comparison

The subject of this research is an important topic, which is frequently repeated, and people need to know its wisdom, and has made it in front and the preface and three detectives, showed through discussion the meaning of the survey on the socks, its wisdom, its rules and conditions, and the duration of the survey on it, spoiled and reasoned and compared to the doctrinal doctrines, And the most correct statement of words I have concluded with a number of things, as follows:

  1. The need to ensure that the slippers are clean, visible and inwa

... Show More
View Publication Preview PDF
Publication Date
Mon May 27 2019
Journal Name
Al-khwarizmi Engineering Journal
Effect of Using Air Guide Net in Front of the Condenser on the Performance of Automobile Air Conditioning System
...Show More Authors

 

The work of this paper is an investigation to improve the condenser performance of the automobile air conditioning system by enhancing the air-side heat transfer from the condenser through the use of an air guide net installed in front of the condenser face which is basically an aluminum plate having a circular entrance shape for the air passage.  The A/C system was examined under two types of test. The first test was conducted the air guide net, while the second was done with the air guide net. The performances of the A/C system under these tests were compared. For the second type of test, the experiment was carried out with three different size of air guide net, three different circular diameters (2, 3 and 3.5 cm) a

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Jun 01 2018
Journal Name
Journal Of Engineering
Experimental Study on Tribological Characteristics of AA 6061 Alloy Reinforced with Al2O3 and B4C Particles
...Show More Authors

Two different composite materials were prepared by stir casting method of AA 6061 alloy as a matrix reinforced with two addition different ceramic materials Al2O3 and B4C of grain size   20 µm by 2.5, 5, 7.5 and10% in weight. The composite material with aluminum alloy as a matrix possesses a unique mechanical properties such as: high specific strength and hardness, low density, and high resistance to corrosion and friction wear. This composite is widely used in automotive parts space and marine applications.

Pin-on-disc technique was used to calculate the wear rate for each addition of Al2O3 and B4C particles. Rockwell hardness test and

... Show More
View Publication Preview PDF
Crossref