Preferred Language
Articles
/
joe-325
Experimental Evaluation of Thermal Performance of Solar Assisted Vapor Compression Heat Pump
...Show More Authors

The thermal performance of indirect expansion solar assisted heat pump, IX-SAHP, was investigated experimentally under Iraqi climate. An Indirect-Solar Assisted Heat Pump system was designed, built, instrumented and tested. Experimental tests were conducted by varying the controlling parameters to investigate their effects on the thermal performance of the IX-SAHP such as cooling water flow rate, heating water flow rate, ambient temperature and solar radiation intensity. The investigation covered values of cooling water flow rate of (2, 3, 4, 5 l/min) and heating water flow rate of (2, 3, 4, 5 l/min) under meteorological condition of Baghdad from November 2014 to January 2015.

The results indicated that the performance of the IX-SAHP is not dependent on the heating water flow rate. On the contrary of heating water flow rate, cooling water flow rate has significant effect on the thermal performance of the system. The COP of the heat pump system is decreased with increasing cooling water flow rate. The collector heat gain increase with increasing the solar radiation and ambient temperature, this leads to increase in COP from 2.2 to 2.39 as the ambient temperature and solar radiation increase from 9.9℃ and 268 W/m2 to 14.9 ℃ and 689 W/m2 respectively.

 

 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Dec 31 2013
Journal Name
Al-khwarizmi Engineering Journal
Numerical Analysis of Double Diffusive Laminar Natural Convection in a Right Angle Triangular Solar Collector
...Show More Authors

A numerical study of the double-diffusive laminar natural convection in a right triangular solar collector has been investigated in present work. The base (absorber) and glass cover of the collector are isothermal and isoconcentration surfaces, while the vertical wall is considered adiabatic and impermeable. Both aiding and opposing buoyancy forces have been studied. Governing equations in vorticity-stream function form are discretized via finite-difference method and are solved numerically by iterative successive under relaxation (SUR) technique. Computer code for MATLAB software has been developed and written to solve mathematical model. Results in the form of streamlines, isotherms, isoconcentration, average Nusselt, and average Sherw

... Show More
View Publication Preview PDF
Publication Date
Thu Jun 01 2023
Journal Name
Iaes International Journal Of Artificial Intelligence (ij-ai)
Evaluation of massive multiple-input multiple-output communication performance under a proposed improved minimum mean squared error precoding
...Show More Authors

<span lang="EN-US">The fundamental of a downlink massive multiple-input multiple-output (MIMO) energy- issue efficiency strategy is known as minimum mean squared error (MMSE) implementation degrades the performance of a downlink massive MIMO energy-efficiency scheme, so some improvements are adding for this precoding scheme to improve its workthat is called our proposal solution as a proposed improved MMSE precoder (PIMP). The energy efficiency (EE) study has also taken into mind drastically lowering radiated power while maintaining high throughput and minimizing interference issues. We further find the tradeoff between spectral efficiency (SE) and EE although they coincide at the beginning but later their interests become con

... Show More
View Publication
Scopus Crossref
Publication Date
Fri Feb 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
Adopting IPSASs and its impact on the quality of financial reporting and performance evaluation in Iraqi government units
...Show More Authors

Abstract

     Performance evaluation is of great importance in all countries of the world, because it has a prominent and effective role in determining the efficiency and effectiveness of the optimal use of available resources, which are rare and important in achieving the desired objectives. With the continued growth of public spending and the limited resources, the State seeks to achieve its objectives through its units with minimal expenditure or deficit, rationality and wastefulness in the spending. In many countries, particularly developing countries, reforms are made in the public sector to achieve that goal through the adoption of IPSAS, which is reflected in the developmen

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Feb 05 2023
Journal Name
Engineering, Technology & Applied Science Research
Performance Evaluation of Emulsion Liquid Membrane on Chlorpyrifos Pesticide Removal: Stability, Mass Transfer Coefficient, and Extraction Efficiency Studies
...Show More Authors

Emulsion Liquid Membrane (ELM) is an emerging technology that removes contaminants from water and industrial wastewater. This study investigated the stability and extraction efficiency of ELM for the removal of Chlorpyrifos Pesticide (CP) from wastewater. The stability was studied in terms of emulsion breakage. The proposed ELM included n-hexane as a diluent, span-80 as a surfactant, and hydrochloric acid (HCl) as a stripping agent. Parameters such as mixing speed, aqueous feed solution pH, internal-to-organic membrane volume ratio, and external-to-emulsion volume ratio were investigated. A minimum emulsion breakage of 0.66% coupled with a maximum chlorpyrifos extraction and stripping efficiency were achieved at 96.1% and 95.7% at b

... Show More
Crossref (2)
Crossref
Publication Date
Tue Sep 01 2020
Journal Name
Journal Of Engineering
Performance Evaluation of Scalar Multiplication in Elliptic Curve Cryptography Implementation using Different Multipliers Over Binary Field GF (2233)
...Show More Authors

This paper presents a point multiplication processor over the binary field GF (2233) with internal registers integrated within the point-addition architecture to enhance the Performance Index (PI) of scalar multiplication. The proposed design uses one of two types of finite field multipliers, either the Montgomery multiplier or the interleaved multiplier supported by the additional layer of internal registers. Lopez Dahab coordinates are used for the computation of point multiplication on Koblitz Curve (K-233bit). In contrast, the metric used for comparison of the implementations of the design on different types of FPGA platforms is the Performance Index.

The first approach attains a performance index

... Show More
View Publication Preview PDF
Crossref (4)
Crossref
Publication Date
Thu Jun 01 2023
Journal Name
International Journal Of Artificial Intelligence (ij-ai)
Evaluation of massive multiple-input multiple-output communication performance under a proposed improved minimum mean squared error precoding
...Show More Authors

<span lang="EN-US">The fundamental of a downlink massive multiple-input multiple-output (MIMO) energy- issue efficiency strategy is known as minimum mean squared error (MMSE) implementation degrades the performance of a downlink massive MIMO energy-efficiency scheme, so some improvements are adding for this precoding scheme to improve its workthat is called our proposal solution as a proposed improved MMSE precoder (PIMP). The energy efficiency (EE) study has also taken into mind drastically lowering radiated power while maintaining high throughput and minimizing interference issues. We further find the tradeoff between spectral efficiency (SE) and EE although they coincide at the beginning but later their interests become con

... Show More
Scopus Crossref
Publication Date
Mon Aug 01 2011
Journal Name
Journal Of Engineering
INVESTIGATION OF TWISTED TAPE TURBULATOR FOR FIRE TUBE BOILER Part I. Heat Transfer
...Show More Authors

The present work presents a new experimental study of the enhancement of turbulent
convection heat transfer inside tubes for combined thermal and hydrodynamic entry length of one
popular “turbulator” (twisted tape with width slightly less than internal tube diameter) inserted for
fire tube boilers. Cylindrical combustion chamber was used to burn (1.6 to 7kg/h) fuel oil #2 to
deliver hot gases with ranges of Reynolds number (10500 to 21700), and (11400 to 24150) for both
empty and inserted tube respectively.A uniform wall temperature technique was used by keeping
approximately constant water temperature difference (25ºC) between inlet and exit cooling water in
parallel flow shell and tube heat exchanger. The test

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sat Sep 30 2017
Journal Name
Al-khwarizmi Engineering Journal
Thermal Conductivity Enhancement of Iraqi Origin Paraffin Wax by Nano-Alumina
...Show More Authors

Abstract

 

Paraffin wax is utilized for the heat storage applications taking advantage from the high stored latent heat during the phase change (from solid to fluid) period. What isn't right with this procedure is that the wax has a little heat transfer rate because of its low thermal conductivity. The thermal conductivity improvement of the paraffin wax has been examined utilizing nano-material with high thermal conductivity. In the recent study, (Al2O3) nanoparticles with weights of 1, 2, and 3% of the paraffin wax were added to the paraffin wax. The Iraqi paraffin wax accessible at the local markets was utilized as a phase change material (PCM).

Many properties of the

... Show More
View Publication Preview PDF
Crossref (8)
Crossref
Publication Date
Mon May 11 2020
Journal Name
Baghdad Science Journal
Acoustic and Thermal Insulation of Nanocomposites for Building Material: Improvement Of Sound And Thermal Insulation Properties Of Nanocomposite
...Show More Authors

This work aims to enhance acoustic and thermal insulation properties for polymeric composite by adding nanoclay and rock wool as reinforcement materials with different rations. A polymer blend of (epoxy+ polyester) as matrix materials was used. The Hand lay-up technique was used to manufacture the castings. Epoxy and polyester were mixed at different weight ratios involving (50:50, 60:40, 70:30, 80:20, and 90:10) wt. % of (epoxy: polyester) wt. % respectively. Impact tests for optimum sample (OMR), caustic and thermal insulation tests were performed. Nano clay (Kaolinite) with ratios ( 5 and 7.5% ) wt.% , also hybrid reinforcement materials involving (Kaolite 5 & 7.5 % wt.% + 10% volume fraction of rockwool ) were added as reinforcem

... Show More
View Publication Preview PDF
Scopus (5)
Crossref (4)
Scopus Clarivate Crossref
Publication Date
Thu Oct 19 2023
Journal Name
Journal Of Optics
Production and characterization of porous silicon via laser-assisted etching as photodetector: effect of different HF concentrations
...Show More Authors

View Publication
Scopus (3)
Crossref (3)
Scopus Clarivate Crossref