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Experimental Study on the Effect of Insertion of Copper Lessing Rings in Phase Change Material (PCM) on the Performance of Thermal Energy Storage Unit
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Abstract

One of the most suitable materials to be used in latent heat thermal energy storage system (LHTES) are Phase change materials, but a problem of slow melting and solidification processes made many researchers focusing on how to improve their thermal properties. This experimental work concerned with the enhancing of thermal conductivity of phase change material. The enhancing method was by the addition of copper Lessing rings in phase change material (paraffin wax). The effect of diameter for the used rings was studied by using two different diameters (0.5 cm and 1cm). Also, three volumetric percentages of rings addition (3%, 6% and 10%) were tested for each diameter. The discharging process was done with four velocities for each case. The obtained results indicated that the maximum volumetric percentage gave a diminished time for melting and maximized the heat transfer in both PCM and air sides as compare with the case of no rings, but the effect of these rings had lower effect on the solidification time. In case of 1 cm rings diameter minimum time for melting was obtained for both 3% and 6% volumetric percentages as compared with the same percentages in case of 0.5 cm diameter rings, while the latter with 10% volumetric percentage overcomes the 1 cm diameter rings for the same previous percentage. Also it can be seen that the minimum velocity (v=1m/s) gave the utmost outlet temperature and with the maximum one (v=3m/s), the minimum solidification time achieved.

Keyword: Thermal energy storage systems, Latent heat storage, Phase change materials, Heat transfer enhancement.

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Publication Date
Fri May 05 2023
Journal Name
International Journal Of Professional Business Review
The Effect of Emotional Intelligence on Manager Performance: a Field Study in the General Authority for Irrigation and Reclamation Projects in Baghdad
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Purpose: the purpose of this study is to investigate how managers working for the General Authority for Irrigation and Reclamation Projects react to the impact of Emotional Intelligence (EI) on their performance.   Theoretical framework: The current study includes an intellectual framework on two variables, namely EI and Manager Performance (MP), because it is essential to investigate the relationship between these two variables and the impact of EI on MP.   Design/methodology/approach: The research problem is that a manager's capacity to make wise decisions about their work or interactions with subordinates is diminished when they have inadequate EI. The questionnaire is used as a tool for gathering data for the study, and the st

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Publication Date
Sat Nov 30 2019
Journal Name
Journal Of Engineering And Applied Sciences
The use of Resource Consumption Accounting and Balanced Scorecard Methods as an Integrated Framework in Correcting the Economic Unit Performance: Applied Study
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Publication Date
Sat Jun 06 2020
Journal Name
Journal Of The College Of Education For Women
Spatial Analysis of Soil Characteristics and its Effect on Determining the Susceptibility of lands of the RasheedRegion: A Study in Soil Geography
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Twelve pends were selected and distributed on three verticals transects paths on the Tigers river in Al Rasheed county.Passing through land covers, that classified and covers the whole region. Based on the 8 Landsat of the year 2015. It was oriental classified by using Erdas 10.2 . The pedons were distributed on the area of each varicty of these classes. the series of soil according of the transect series (DW74,MMg,DMu6 , Df96) respectively were represented P1 , P2 , P3 , P4  .

The second transits series(DM97,MM5,DM96,DF115) respectively were  represented P5 , P6 , P7 , P8  .The third  transits series(DM46,MMg,MF12,MM11) re

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Publication Date
Mon Mar 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
The ethical dimension of administrative accountants And its impact on the improvement and growth of staff potential in the economic unit
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تعد المحاسبة بشكل عام علماً لكنها ليست من العلوم الصرفة وإنما من العلوم الإجتماعية مما يتطلب للتعامل مع المواضيع المحاسبية الأخذ بنظر الاعتبار الأشخاص المعنيين بالموضوع سواء كانوا المعدين للمخرجات المحاسبية أي المحاسبين، أو الاطراف ذوي المصالح المعنيين والمستفيدين من هذه المخرجات أي المستخدمين، ويعد المحاسب جزءاً من العملية الاجرائية نفسها وبهذا يكون دوره مزدوجاً يجمع بين كونه القائم بالبحث والقي

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Publication Date
Tue Dec 30 2014
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Performance Evaluation of Three Phase Spray Direct Contact Heat Exchanger
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The present investigation deals with experimental study of three-phase direct-contact heat exchanger, for water-Freon R11 system, where water is the continuous phase (liquid) and Freon R11 (liquid-gas) is the dispersed phase. The test section consisted of a cylindrical Perspex column with inner diameter 8cm and 1.2m long, in which, water was to be confined. Liquid Freon R11 drops were injected into the hot water filled column, through a special design of distributors at the bottom of the column. The liquid Freon R11 drops rose on their way up and evaporated into two-phase bubbles at atmospheric pressure. The study was devoted to express the effect of process variables such as c

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Publication Date
Sat Jun 15 2019
Journal Name
Journal Of The College Of Basic Education
The Effect Of Phoenix Dactylifera L. Pinnae Reinforcement On The Mechanical And Thermal Properties Of Polymer Composite
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Phoenix dactylifera l. pinnae (the green leaves of dates palm) were used as natural reinforcing (strengthening) fibers to improve the mechanical properties of polyester as a matrix material, the fibers of the green leaves of dates palm were used in two lengths, 10 and 20mm with five rates of 0, 2.5, 5, 10, and 20% , where the reinforcing with the leaves fibers increases the hardness strength from 76.5 to be about 86.55 , the Impact value raised from about 0.313 to 0.461 , in addition to that the flexural strength from 2.66 to be about 55 , and the thermal conductivity increases from 2.54 𝑤∕𝑚.℃ to 5.41 𝑤∕𝑚.℃. The results of the present search explains that the composite samples reinforced at rate 20% and 10mm fiber length

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Publication Date
Mon Jun 19 2023
Journal Name
Journal Of Engineering
Study of Some Mechanical Properties for a Polymer Material Reinforcement with Chip or Powder Copper
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In this paper, chip and powder copper are used as reinforcing phase in polyester matrix to form composites. Mechanical properties such as flexural strength and impact test of polymer reinforcement copper (powder and chip) were done, the maximum flexural strength for the polymer reinforcement with copper (powder and chip) are (85.13 Mpa) and (50.08 Mpa) respectively was obtained, while the maximum observation energy of the impact test for the polymer reinforcement with copper (powder and chip) are (0.85 J) and (0.4 J) respectively  

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Crossref
Publication Date
Sun Dec 01 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Job satisfaction and its relation to the effectiveness of performance: Applied research on a sample of employees in the Federal board of supreme Audit
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The research aimed to study the job satisfaction of the staff of the Federal board of supreme Audit and its relation to the effectiveness of their performance, The questionnaire was adopted as a main tool in the collection of data and information from a random sample of (54) employees of the Federal board of supreme Audit. In light of this, the data were collected and analyzed and the hypotheses were tested using the statistical program (SPSS).

The researchers reached a number of conclusions, the most important of which were: (1) the respondents' response to the variables of job satisfaction and the effectiveness of the performance were medium; (2) there was a significant relationship between job satisfaction and performance effe

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Publication Date
Tue Sep 01 2009
Journal Name
Journal Of Economics And Administrative Sciences
Impact of budget on the basis of activities in the implementation of competitive strategiesApplied Study in the General Company for Electrical Industries - Tammuz Laboratory
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The Contemporary Business Environment is Surrounded by many quick and continues variable and changes which has an effect on the economic units. These variables and changes like the high competition which need many tools to help them to continue and achieve The critical success. So to achieve this they have many competitive strategies like cost leadership strategy, differentiation strategy and focus strategy.

Budget is regarded one of main tools to execute objectives polices and programs of the economic units, beside show how the economic units had execute the available economic resources.

Activity based on budgeting is regarded one of the modern technique in the m

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Crossref
Publication Date
Fri Jun 30 2017
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Study the Performance of Nanozeolite NaA on CO2 Gas Uptake
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The adsorption isotherms and kinetic uptakes of CO2 were measured. Adsorption isotherms were measured at two temperatures 309 K and 333 K and over a pressure range of 1 to 7 bar. Experimental data of CO2 adsorption isotherms were modeled using Langmuir, Freundlich and Temkin. Based on coefficient of correlation it was found that Langmuir isotherm model was well suited with the experimental data of CO2 adsorption isotherms.  In addition, Adsorption kinetic of CO2 mixture with N2 containing 10 % by volume CO2 and 90 % by volume N2 were determined in a temperature 36 °C and under the atmospheric pressure .When the flow rate was increased from

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