Due to the potential cost saving and minimal temperature stratification, the energy storage based on phase-change materials (PCMs) can be a reliable approach for decoupling energy demand from immediate supply availability. However, due to their high heat resistance, these materials necessitate the introduction of enhancing additives, such as expanded surfaces and fins, to enable their deployment in more widespread thermal and energy storage applications. This study reports on how circular fins with staggered distribution and variable orientations can be employed for addressing the low thermal response rates in a PCM (Paraffin RT-35) triple-tube heat exchanger consisting of two heat-transfer fluids flow in opposites directions through the inner and the outer tubes. Various configurations, dimensions, and orientations of the circular fins at different flow conditions of the heat-transfer fluid were numerically examined and optimized using an experimentally validated computational fluid-dynamic model. The results show that the melting rate, compared with the base case of finless, can be improved by 88% and the heat charging rate by 34%, when the fin orientation is downward–upward along the left side and the right side of the PCM shell. The results also show that there is a benefit if longer fins with smaller thicknesses are adopted in the vertical direction of the storage unit. This benefit helps natural convection to play a greater role, resulting in higher melting rates. Changing the fins’ dimensions from (thickness × length) 2 × 7.071 mm2 to 0.55 × 25.76 mm2 decreases the melting time by 22% and increases the heat charging rate by 9.6%. This study has also confirmed the importance of selecting the suitable values of Reynolds numbers and the inlet temperatures of the heat-transfer fluid for optimizing the melting enhancement potential of circular fins with downward–upward fin orientations.
The environment contemporary works for the insurance companies have seen a number of technological developments and changes rapidly in light of the intense competition in the insurance market, and this affects human behavior in the workplace, and to director in his work needs to be a set of managerial skills. so we find compensation activity in companies insurance needs a high managerial skills, so that compensation, director of the settlement procedure successfully. So research aims to test two hypotheses two major belongings variables search using some statistical methods to extract the results and interpretation and analysis (such as arithmetic mean, standard deviation, percentages, Alpha Cronbach's coefficient, Pearson correlation co
... Show MoreThe current research aims to identify the effect of Baska style on students’ achievement and the creative thinking in material rhetoric and the application of students for fifth grade literary. To achieve the study objectives, the researcher has designed an achievement test to measure group of students in the fifth grade literary in material application. The researcher chose a sample of 40 female students from Khansa School for Girls in Baghdad for the academic year (2014 - 2015), he applied the test on an exploratory sample consisted of 30 female students from the research community. The study resulted in being no statistically significant difference at the level of significance (0.05) between the mean scores of the experimental group
... Show MoreIn diabetes, impaired wound healing and other tissue abnormalities are considered major concerns. Many factorsaffect the time and quality of wound healing. One of the purposes of medical sciences is wound healing in a short time withreduced side effects. The herbal products are more precious in both prophylaxis as well as curative in delayed diabetic woundhealing activity when compared to synthetic drugs.A wide range of evidence has shown that capers plant possesses differentbiological effects, including antioxidant, anticancer and antibacterial effects. Phytochemical analysis shows thatC. spinosahashigh quantities of bioactive constituents, including polyphenolic compounds, which are responsible for its health-promotingeffects. The healing
... Show MoreThis research is concerned with qualitatively studying the history of an ancient family, one of the most prominent noble, Alawite families, that assumed the position of the Student Union for the Alawite Supervision in the city of Nishapur in Khorasan during the centries (4-6 H./ 10-12 A.H.). Thus, the research aims to investgate the historical news, and the outstanding Zubarah figures who experience the supereme the religious, historical and scientific position in Khorasan generally and Nishapur particularily. It further aims at arriving at the true meaning of the name Zubarah, and to whom it was called, and the extent of this family’s affiliation to the noble Alawi House, and how they moved to live and settle in the cities of the East
... Show MoreSocial Aspects in the Kingdom of Mali Through Ibn Battuta's book Tuhfat Alnuddar in Garaeb Al Amsar Wa Ajaeb Al Asfar
Abstract:
The tax is one of the elements of the general revenues of the state and contributes to covering its expenses. Taxes are imposed in most countries of the world. The tax proceeds depend on a set of factors that contribute either positively or negatively to the tax share by increasing or decreasing it. Therefore, the research aims to demonstrate the role of the tax examiner's procedures in achieving the validity of the taxable base and its reflection on the tax proceeds, as well as reviewing the tax examiner's procedures related to the tax return process. Examination and tax audit of the financial statements, as well as presenting the financial statements to an independent and i
... Show MoreAfter Hamdallah and his success on the realization of this manuscript (a letter in detail what was said in the parents of the Prophet Ibn Kamal Pasha (d. 940 e) study and investigation I will review some of the results reached in the realization of this manuscript:
1. The hadiths mentioned in this manuscript are mostly placed or weak.
2 - We are not entitled to speak about the silence of the law for saying Almighty ﭽ ﮮ ﮯ ﮰ ﮱ ﯓ ﯔ ﯕ ﯖ ﯗ ﯘ ﯙ ﭼ Table: 101.
3 in which harm to our Holy Prophet وله تع ﮂ ﮃ ﮄ ﮅ ﮆ ﮈ ﮉ ﮊ ﮋ ﮌ ﮍ ﮎ ﭼ parties: 57.
4 Because the parents of the Prophet of the people of the period ordered them to God for the Almighty ﭽ ﯨ ﯩ ﯪ ﯫ ﯬ
Interleukins (IL-2 and IL-4) are increased in asthmatics and were reported to induce resistance to steroid therapy in some patients who fail to get benefit from glucocorticoids when used in full dose and for long period of time. In this context, the present study was conducted on Iraqi patients to provide additional laboratory mean, beside the clinical diagnosis, for the decision whether the asthma is steroid sensitive or resistant by monitoring the level of immunoglobulins, complement proteins and interleukins among asthmatic patients (steroid sensitive or resistant) and the possible contribution of other factors like age, sex and environments in the development of steroid resistance. A total number of 55 asthmatics and 28 normal subjec
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