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%.
Abstract: This research aims to investigate and analyze the most pressing issues facing the Iraqi economy, namely economic stability and inclusive growth Consequently, the present study investigates the effect of inflation and unemployment, which are significant contributors to economic instability, on inclusive growth dimensions such as GDP, education, health, governance, poverty, income inequality, and environmental performance. From 1991 to 2021, secondary data were collected using World Bank Indicators (WDI) and Organization for Economic Cooperation and Development (OECD) databases. The researchers also employed the autoregressive distributed lag (ARDL) model to determine the relationship between variables. The study revealed that fluct
... Show MoreThe study aimed to examine the sensitivity to stress and its relation to positive mood among educational supervisors. The researcher used the descriptive approach as more an appropriate method for the current study. The sample is composed of (200) educational supervisor. To collect study data, two scales have been used: one scale to measure the sensitivity to stress and the other to measure the positive mood. The results indicated that a high level of sensitivity to stress with low level of positive mood among educational supervisors, sensitivity to stress showed significant differences among the sample regarding to major. There is no correlation between sensitivity to stress and positive mood, and finally, there are no significant diffe
... Show More134 samples of plants and animals wastes were taken from three different regions outside Baghdad and three different regions in Baghdad. 24 cellulolytic isolates fungi AO, C1, TH1, AN1, R1, TV, PG, AF, B1, L1, AP, TH, AP1, AN3, AO2, A, A1, C, F, AO1, C2, F1, CL and AP2 independent were chosen out of 48 selected fungi. The best optimal conditions for growth were 30ºC and pH 7. The isolates were identified and screened according to the colony diameter, biomass and density of spores in addition of capability to produce the hydrolytic enzymes for cellulose.
This research seeks to determine the nature of the relationship that brought together writing and memories,These memories have given the play (Bells and Trains) a new life, and brought it from one mold to another , And she re-drawn and produced it through words and imagination, and since they are important dramatic keys, they gave the writer the ability to maneuver. This play embodies part of the writer's suffering and an important part of his life It represents a journey into memories of the past through which the writer tried to narrate events that he lived and knew from his friends and relatives, It is the events of the Holocaust and its repercussions on the psyche of the Jews. This play is like a journey in memory with many feelings of
... Show MoreThe aim of this study to investigate the sexual harassment, prevention strategies, and the appropriate ways that tackle this phenomena. The current research consisted of four chapter; the first chapter gave a general introduction about the targeted topic followed by the problem of statement, the significance of study, study’s aims, and end with the limitations of study. The second section of chapter one referred to the common concepts of study. Third section addressed the previous studies that related to the current one. Chapter two concerned with the sexual violence against minors. It has four section; first section addressed number of concepts which related to sexual violence. The second section focused on the implications of sexual
... Show MoreJeder Lernende, der in der Fremdsprache Deutsch kommunizieren möchte, wird sich auch mit der deutschen Aussprache beschäftigen (müssen). Wer eine gute Aussprache hat, wird nicht nur oft und zu Recht bewundert, er hat es auch leichter, die deutsche Sprache zu verstehen, und er wird gut verstanden. Aussprachefehler beeinträchtigen die Kommunikation, sie führen zur Unverständlichkeit von Namen, Wörtern und Äußerungen oder Mißverständnissen, sie bewirken Ermüdung und Konzentrationsverluste und beeinträchtigen die Sprachverarbeitung durch Assoziationen und Emotionen, die beim Hörer entstehen können.’’[1]
Diese vorliegende Forschung befasst sich mit der Wic
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ملخص البحث:
ان الله تعالى هو الذي خلق جميع المخلوقات ، والذي بيده الموت والحياة وان كل هذه المخلوقات تحتاج الى اوامر ، وهذه الاوامر الالهية وجهها الله لعبادة بوساطة انبياءه ( عليهم السلام) فكانوا هم اول المستسلمين والمنقادين لأوامره ، فجاءت الآيات الكريمة مخاطبة للأنبياء واقوامهم بشكل عام ولنبينا محمد (r) بشكل خاص.
اما عن المضمون البحثي فقد جاءت مادته مقسمة الى ثل
... Show MoreThe spectral response of the Si solar cell does not coincidence with the sun irradiance spectrum, so the efficiency of the Si solar cell is not high. To improve the Si solar cell one try to make use of most region of the sun spectrum by using dyes which absorb un useful wavelengths and radiate at useful region of spectrum (by stock shift). Fluorescence's dye is used as luminescent concentrator to increase the efficiency of the solar cell. The results show that the performance efficiency and out power for crystalline silicon solar cells are improved.
How I was eager to research the ruling on three of the most dangerous types to Islam and Muslims (the heretic, the sorcerer, the innovator, and related terms).
Because it is the most dangerous deadly disease that destroys the hearts of Muslims, and may even expel a Muslim from the circle of Islam, and how many Muslims have done or committed such a thing without knowing it. Indeed, how many Muslims have left Islam and whose wife has abandoned him without realizing it, and among them are those who have committed it without knowing it. As well as related words associated with heresy.( )
Because people debated such matters between extremists and lenient ones, most of whom were extremists, and they did not reach a conclusion. So I decid
The current research aimed to identify psychological stability and its relationship to university integration and spiritual intelligence among university students. The research sample consisted of (158) students from the College of Education - Al-Mustansiriya University.
A scale was applied: psychological stability, university integration, and spiritual intelligence, and by using the (Pearson) correlation coefficient, and the t-test, the results showed: the sample members enjoy psychological stability, university integration, and spiritual intelligence, and there is a positive, statistically significant correlation between the research variables, and the results resulted in some recommendations and proposals.