In this study, the effect of the thermal conductivity of phase change material (PCM) on the performance of thermal energy storage has been analyzed numerically. A horizontal concentric shell-and-tube latent heat thermal energy storage system (LHTESS) has been performed during the solidification process. Two types of paraffin wax with different melting temperatures and thermal conductivity were used as a PCM on the shell side, case1=0.265W/m.K and case2=0.311 W/m.K. Water has been used as heat transfer fluid (HTF) flow through in tube side. Ansys fluent has been used to analyze the model by taking into account phase change by the enthalpy method used to deal with phase transition. The numerical simulation assumptions were three-dimensional, transient, and laminar flow was used. The result for the PCMs of performance, temperature distribution, and liquid fraction during the discharge process were compared to each other. Furthermore, the Nusselt number was analyzed. The result showed that the increase in thermal conductivity of PCM reduces the time of the solidification process by 20%. The performance of LHTESS for case 2 is 63.2%, whereas for case1 is 54.6%.
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The international organizations showed their interest in the marketable public relations, with their activities, means and strategies, they play a crucial role in marketing products, services and ideas of the institution. They are considered to be the link between the company and its public, They are responsible for presenting the institution to the public, with honest transmission of the information. This gives a good impression to the institution, in a way the institution and its products become consistent with the needs and interests of the public. Based on this, the research aims to identify the strategies used by the marketable public relations internationally. The r |
Purpose: As a result of the sudden and ill-considered trade openness of Iraq after 2003 to the countries of the world in general and the neighboring countries in particular, and in the absence of the necessary support for the national productive forces and the lack of effective standardization and quality control devices, this led to the exposure of most local products, especially agricultural ones, to decline and inability On the competition and thus dumping the Iraqi market, especially the agricultural products, with imported products, this study came to find out the effect that dumping has on the local production of chicken meat and the impact of that impact on the size of the food gap, and whether the results of the practica
... Show MoreThe aim of the research is to evaluate the response of the researched leaders towards practicing the concept of the lens, which is its dimensions with (stakeholders, resource mobilization, knowledge development, culture management) and the nature of its relationship to tax pioneer performance represented in its dimensions (strategic direction, leadership indicators, growth, renewal and modernization, efficiency, Effectiveness) The questionnaire was approved as a main tool in collecting data and information from the sample members in the General Authority of Taxes, which number (91) Who are on (M. General Manager, Division Director, Deputy Director, Senior Division Director, Deputy Director, Second Division, Division Officer, M. D
... Show MoreThe research aims to demonstrate the impact of tax techniques on the quality of services provided to income taxpayers by studying the correlational and influencing relationships between the exploited variable (tax techniques) and the dependent variable (the quality of services provided to income taxpayers), and in line with the research objectives, the main hypothesis of the research was formulated (there is a relationship Significance between tax techniques and the quality of services provided to income taxpayers) a number of sub-hypotheses emerged from this hypothesis that were stated in the research methodology, and a number of conclusions were reached, the most important of which were (through the use of the correlation coeff
... Show MoreThe problem of research is that there are differences between learners in processing in formation in general and there is variation at the learners level perform scrolling skill of the passes up and down by the volley ball .Therefore the researchers decided to conduct astudy through which identify the relationship between information processing and the skill of scrolling from the top and bottom by the volleyball. The researchers used the descriptive approach by themethod of interconnectivity .Asampleconsist of21 students from first staye in collage of physical education and sports science for Girls(university of Baghdad) and attest has been applied(process information and scroll up and down) on the research sample after the required
... Show MoreThe study involved the removal of acidity from free fatty acid via the esterification reaction of oleic acid with ethanol. The reaction was done in a batch reactor using commercial 13X zeolite as a catalyst. The effects of temperatures (40 to 70 °C) and reaction time (up to 120 minutes) were studied using 6:1 mole ratio of pure ethanol to oleic acid and 5 wt. % of the catalyst. The results showed that acid removed increased with increasing temperature and reaction time. Also, the acidity removal rises sharply during the first reaction period and then changes slightly afterward. The highest acidity removal value was 67 % recorded at 110 minutes and 70 °C. An apparent homogeneous reversible reaction kinetic model has been proposed a
... Show MoreBackground: The roles of AI in the academic community continue to grow, especially in the enhancement of learning outcomes and the improvement of writing quality and efficiency. Objectives: To explore in depth the experience of senior pharmacy students in using artificial intelligence for academic purposes. Methods: This qualitative study included face-to-face individual interviews with senior pharmacy students from March to May 2023 using a pre-planned interview guide of open-ended questions. All interviews were audio-recorded. Thematic analysis was used to analyze the data. Results: The results were obtained from 15 in-depth face-to-face interviews with senior pharmacy students (5th and 4th years). Eight participants were male, an
... Show MoreBackground: The roles of AI in the academic community continue to grow, especially in the enhancement of learning outcomes and the improvement of writing quality and efficiency. Objectives: To explore in depth the experience of senior pharmacy students in using artificial intelligence for academic purposes. Methods: This qualitative study included face-to-face individual interviews with senior pharmacy students from March to May 2023 using a pre-planned interview guide of open-ended questions. All interviews were audio-recorded. Thematic analysis was used to analyze the data. Results: The results were obtained from 15 in-depth face-to-face interviews with senior pharmacy students (5th and 4th years). Eight participants were male, and seven
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