Preferred Language
Articles
/
alkej-358
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 wax were changed due to the addition of nanofillers. The wax color was changed from light brown to white. The thermal conductivity of the paraffin wax was expanded by increasing the additional nanoparticles extent with 37.1, 42.3 and 60.32% for 1, 2 and 3% added nano-Al2O3 compared to pure wax conditions. The subsequent change in the thermal conductivity of the paraffin wax makes it reasonable for the use in thermal storage applications.

 

Keywords: Latent heat, Nano-alumina, Paraffin wax, Thermal storage,

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri Jun 01 2018
Journal Name
Materials Science-poland
Thermal and electrical properties of polyimide/PANI nanofiber composites prepared via in situ polymerization
...Show More Authors
Abstract<p> Polyimide/polyaniline nanofiber composites were prepared by in situ polymerization with various weight percentages of polyaniline (PANI) nanofibers. X-ray diffraction (XRD) and Fourier transform infrared spectra (FT-IR), proved the successful preparation of PANI nanofiber composite films. In addition, thermal stability of PI/PANI nanofiber composites was superior relative to PI, having 10 % gravimetric loss in the range of 623 °C to 671 °C and glass transition temperature of 289 °C to 297 °C. Furthermore, the values of the loss tangent tanδ and AC conductivity σAC of the nanocomposite films were notably higher than those of pure polyimide. The addition of 5 wt.% to 15 wt.% PANI</p> ... Show More
View Publication
Scopus (40)
Crossref (36)
Scopus Clarivate Crossref
Publication Date
Sat Aug 31 2019
Journal Name
Iraqi Journal Of Physics
Investigation the effect of post deposition thermal treatment on properties P3HT and P3HT:PCBM blend.
...Show More Authors

  This work reports the study of heat treatment effect on the structural, morphological, optical and electrical properties of poly [3-hexylthiophene] and its blend with [6,6]-phenyl C61 butyric acid methyl ester ( P3HT:PC61BM). X-ray diffraction (XRD) measurements show that the crystallinity of the films increased with annealing. The evaluation of surface roughness and morphology was investigated using atomic force microscope (AFM), and field emission scanning microscope(FESEM). The optical properties were emphasized a strong optical absorption of P3HT compared with the blend. Hall effect measurement was used to study the electrical properties which revealed there is an increase in the electrical conductivity and Hall mobility of th

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Fri Mar 05 2021
Journal Name
Materials
Optimum Placement of Heating Tubes in a Multi-Tube Latent Heat Thermal Energy Storage
...Show More Authors

Utilizing phase change materials in thermal energy storage systems is commonly considered as an alternative solution for the effective use of energy. This study presents numerical simulations of the charging process for a multitube latent heat thermal energy storage system. A thermal energy storage model, consisting of five tubes of heat transfer fluids, was investigated using Rubitherm phase change material (RT35) as the. The locations of the tubes were optimized by applying the Taguchi method. The thermal behavior of the unit was evaluated by considering the liquid fraction graphs, streamlines, and isotherm contours. The numerical model was first verified compared with existed experimental data from the literature. The outcomes re

... Show More
View Publication Preview PDF
Scopus (17)
Crossref (18)
Scopus Clarivate Crossref
Publication Date
Tue Jan 01 2019
Journal Name
Fme Transactions
Thermal-hydraulic hot-spot analysis of IRT-5000 nuclear research reactor: Comparative safety evaluation
...Show More Authors

A detailed methodology is presented in this paper for the calculation of nucleate boiling safety margin (NBSM) in nuclear research reactors using a temperature function with three different thermal-hydraulic hot-spot analyses: nominal, cumulative and statistical for normal operating condition and coolant flow variation. A computer simulation program is developed for applying the methodology to the IRT-5000 reactor based on experimental core data. According to cumulative analysis as the overconservative approach, the NBSM at normal operating condition of thermal power 5 MW and coolant velocity 1.672 m/s was 2.3% with reactor power limit 5.13 MW. However, during power or coolant flow trip condition, transient nucleate boiling would occur for

... Show More
View Publication
Scopus Crossref
Publication Date
Tue Dec 01 2020
Journal Name
Thermal Science And Engineering Progress
Investigation of steam jet flash evaporation with solar thermal collectors in water desalination systems
...Show More Authors

View Publication
Scopus (15)
Crossref (8)
Scopus Crossref
Publication Date
Thu Dec 01 2011
Journal Name
International Review Of Physics (e-journal) (irephy)
Red shift band enhancement of the nanostructure ZnO100-xAlx thin films as a function of Al concentration for optoelectronic applications
...Show More Authors

Preview PDF
Publication Date
Tue May 01 2018
Journal Name
Journal Of Engineering
Performance enhancement of Echo Cancellation Using a Combination of Partial Update ( PU) Methods and New Variable Length LMS (NVLLMS) Algorithm
...Show More Authors

In this paper, several combination algorithms between Partial Update LMS (PU LMS) methods and previously proposed algorithm (New Variable Length LMS (NVLLMS)) have been developed. Then, the new sets of proposed algorithms were applied to an Acoustic Echo Cancellation system (AEC) in order to decrease the filter coefficients, decrease the convergence time, and enhance its performance in terms of Mean Square Error (MSE) and Echo Return Loss Enhancement (ERLE). These proposed algorithms will use the Echo Return Loss Enhancement (ERLE) to control the operation of filter's coefficient length variation. In addition, the time-varying step size is used.The total number of coefficients required was reduced by about 18% , 10% , 6%

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Wed Jun 30 2021
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Effect of Temperature on Gas and Liquid Products Distribution in Thermal Cracking of Nigerian Bitumen
...Show More Authors

The increasing population growth resulting in the tremendous increase in consumption of fuels, energy, and petrochemical products and coupled with the depletion in conventional crude oil reserves and production make it imperative for Nigeria to explore her bitumen reserves so as to meet her energy and petrochemicals needs. Samples of Agbabu bitumen were subjected to thermal cracking in a tubular steel reactor operated at 10 bar pressure to investigate the effect of temperature on the cracking reaction. The gas produced was analyzed in a Gas Chromatograph while the liquid products were subjected to Gas Chromatography-Mass Spectrometry (GC-MS) analysis. Heptane was the dominant gas produced in bitumen cracking at all temperatures and the r

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Sep 01 2016
Journal Name
Journal Of Saudi Chemical Society
Synthesis and investigation of thermal properties of vanadyl complexes with azo-containing Schiff-base dyes
...Show More Authors

Azo-Schiff base compounds (L1 and L2) have been synthesized from the reaction of m-hydroxy benzoic acid with 1,5-dimethyl-3-[2-(5-methyl-1H-indol-3-yl)-ethylimino]-2-phenyl-2,3- dihydro-1H-pyrazol-4-ylamine and with 3-[2-(1H-indol-3-yl)-ethylimino]-1,5-dimethyl-2-phenyl- 2,3-dihydro-1H-pyrazol-4-ylamine. The free ligands and their complexes were characterized based on elemental analysis, determination of metal, molar conductivity, (1H, 13C) NMR, UV–vis, FT-IR, mass spectra and thermal analysis (TGA). The molar conductance data revealed that all the complexes are non-electrolytes. The study of complex formation via molar ratio in DMF solution has been investigated and results were consistent to those found in the solid complexes with a rat

... Show More
View Publication Preview PDF
Scopus (41)
Crossref (31)
Scopus Clarivate Crossref
Publication Date
Sun May 01 2022
Journal Name
Civil Engineering Journal
Phases of Urban Development Impact on the Assessment of Thermal Comfort: A Comparative Environmental Study
...Show More Authors

Millions of pilgrims and visitors from numerous parts of the world flock to Karbala (one of the most prominent ideological and religious places in central Iraq) each year to visit the holy shrines in Karbala due to their sanctity. Many improvements have been made to the Two Holy Shrines (THS), the Shrines of Imam Husayn and Imam Abbas, and the area between them (ATHS), due to the high temperatures in this region and to improve pedestrian thermal comfort. Studies on improving outdoor thermal comfort in Karbala are scarce. Hence, this research aims to look into historical and current architectural changes and how they affect thermal comfort. On the hottest summer day, the ENVI-met software program was used to simulate the building des

... Show More
View Publication
Scopus (16)
Crossref (14)
Scopus Clarivate Crossref