Phase change material (PCM) is considered as one of the most effective thermal energy storage (TES) systems to balance energy supply and demand. A key challenge in designing efficient PCM-based TES systems lies in the enhancement of heat transmission during phase transition. This study numerically examines the privilege of employing twisted-fin arrays inside a shell-and-tube latent heat storage unit to improve the solidification performance. The presence of twisted fins contributes to the dominating role of heat conduction by their curved shapes, which restricts the role of natural convection but largely aids the overall heat-transfer process during solidification. The heat-discharge rate of twisted-fin configuration is increased by ∼14 and ∼55% compared to straight fin and no fin configurations—leading to a reduction in the solidification duration by ∼13 and ∼35%, respectively. The solidification front at various times has also been assessed through a detailed parametric study over the fin height, fin pitch number, and fin thickness. Over the range of values assumed, the fin height is the most dominant parameter – increasing the heat-retrieval rate from 10.0 to 11.4 W and decreasing the discharge time from above 3600 to 2880 s by varying the fin height from 2.5 to 7.5 mm.
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... Show MoreSeven species of semi venomous Opisthoglypha snakes (Reptilia, Ophidia) of Iraq are listed with important characteristics in morphology due to geographical and individual variation of species, as well, the confusion in the scales count of Telescopus tessellatus martini (Schmidt, 1939) of Iraq are discussed.
This paper discusses the Sums of Squares of “m” consecutive Woodall Numbers. These discussions are made from the definition of Woodall numbers. Also learn the comparability of Woodall numbers and other special numbers. An attempt to communicate the formula for the sums of squares of ‘m’ Woodall numbers and its matrix form are discussed. Further, this study expresses some more correlations between Woodall numbers and other special numbers.
Abstract A descriptive study to assess of factors that contributes of lung cancer. The study was carried out in Specialized Surgery teaching hospital, Ibin Al- Beetar hospital and Ibin Al- Nafees hospital for the period From January 2004 to October 2004 .The study aimed to assess the factors that contribute to lung cancer and to identify the relationship between the variables of the study with lung cancer. A purposive (non-probability) sample of (70) patients with lung cancer was selected for the study. An assessment form was employed for the purpose of the study. Test- retest reliability was employed through
Standards of audit have been defined issued them by professional organizations the audit risk is: Failure of the auditor inadvertently to amend his opinion on the financial statements in suitable method, although these statements are Interpolated Essentially. As result the deep impacts caused by electronic operating systems in the accounting data in the audit process which audit risk has gained attention of many professional sides, especially the audit process and quality is relating with level of discovery the auditor for the mistakes of origin (misrepresentations) all their types and give the necessary confidence for the auditor to express his technical opinion in fidelity and certified financial statements which prepared electronicall
... Show MoreThe discussion in this paper gives several theorems and lemmas on the Sums of Squares of consecutive Carol Numbers. These theorems are proved by using the definition of carol numbers and mathematical induction method. Here the matrix form and the recursive form of sum of squares of consecutive Carol numbers is also given. The properties of the Carol numbers are also derived.
Background: Intramedullary astrocytomas
account for about 1% of all CNS tumors and
6–8% of spinal cord tumors. The vast majority
of intramedullary astrocytomas are slowgrowing
lesions.
Objectives: The goal in this study was to
review a series of patients who underwent
surgical removal of intramedullary high-grade
astrocytomas, focusing on the functional
outcome and the effect of multimodality
treatment on the survival of patients with high
grade intramedullary astrocytoma.
Methods: Between June 1999 and June 2004,
22 patients underwent removal of
intramedullary high-grade astrocytomas in four
neurosurgical hospital in Baghdad/ Iraq
(Neurosurgical hospital, Al Shaheed Adnan
Hospital for
Seven species of semi venomous Opisthoglypha snakes (Reptilia, Ophidia) of Iraq are listed with important characteristics in morphology due to geographical and individual variation of species, as well, the confusion in the scales count of Telescopus tessellatus martini (Schmidt, 1939) of Iraq are discussed.
