This paper aims to study the effect of circular Y-shaped fin arrangement to improve the low thermal response rates of a double-tube heat exchanger containing Paraffin phase change material (PCM). ANSYS software is employed to perform the computational fluid dynamic (CFD) simulations of the heat exchanger, including fluid flow, heat transfer, and the phase change process. The optimum state of the fin configuration is derived through sensitivity analysis by evaluating the geometrical parameters of the Y-shaped fin. For the same height of the fins (10 mm), the solidification time is reduced by almost 22%, and the discharging rate is enhanced by almost 26% using Y-shaped fins compared with the straight fins. The results demonstrate that the solidification time is inversely proportional to the fin's length. The heat release rate for the case with the longest fins (stem length of 10 mm) is 39 W, almost 2.8 times higher than that with the fins' stem length of 5 mm. The case with the tributary's angle of 22.5o solidified in 55 min, faster than the other studied angles. Increasing the number of fins significantly affects the solidification time and discharging rate. By increasing the number of fins from 3 to 9, the heat transfer rate improves by 194%. The advantages of circular Y-shaped fins are well known in heat transfer applications and therefore are characterized toward higher performance in this study for the first time during the solidification process.
Search procedures on the treatment research has tended include what cam followers Astaratejaat available to the business organizations to achieve competitive advantage and continued benefits of the form in which the organization can maintain its success in the race competitive and increase production efficiency.
The objectives of the study , the study came with the number of goals and the most important one the knowledge of the relationship and the influence between the variables of the study and review of the latest literature frameworks intellectual and philosophical to the variables of the study and come up with recommendations that could help the organization improve its performance .
... Show MoreObjective(s): The study aims at evaluating pregnancy-related health behaviors for pregnant women, and to identify the association between pregnancy-related health behaviors and their demographic characteristics of pregnant woman’s age, education, employment, residential area and monthly income.
Methodology: A descriptive study is carried out for the period from December 14th, 2020 to June 20th, 2021. This study was conducted through a non-probability (convenience) sample of 150 pregnant women attending, Abo Ghareeb primary health care sector in Abo Ghareeb spend. The sample has been collected by using the instrument to gather data and accomplish the study's objectives. A questionnaire is composed of (29) items and it is divided into
This study was carried out in the bee laboratory in the Faculty of Agriculture –University of Kufa in September 2021 to evaluate some protein sources and hive products against the oriental hornet Vespa orientalis Linnaeus 1771 (Hymenoptera: Vespidae). The food sources included: beef meat, gut fish, beef lung, honeybee, wax, propolis, pollen, bee worker, and water, in addition to control which was an empty petri dish. The number of visits and their duration were calculated. The results showed that the wasps preferred bee honey and wax significantly higher than the rest of the stimuli.
Objective: To identify the effectiveness of instruction oriented intervention for primipara women upon episiotomy and self
perineal care.
Methodology: A quasi-experimental study was carried out to determine the effectiveness of instruction-oriented
intervention for primipara women upon episiotomy and self-perineal care. A purposive "non-probability" sample of (60)
primipara mothers was selected from Ibn AL-Balady Pediatric and Maternity Hospital, Al-russafa, Baghdad. The sample
has been divided into two groups; (30) primipara women who were considered as a study group, and another (30) primipara
women who were considered as a control one. The study group was exposed to an instruction-oriented intervention. While,
the
This research aims to show the nature of the impact of proactive and analytical strategic orientation in the dimensions of tax organizational excellence (leadership, strategic planning, information and analysis and knowledge management, focus on taxpayers, focus on operations, focus on workforce, business results), in the General Tax Authority The questionnaire was used as a tool to collect data and information from the sample of (110) who are (Associate Director General, Head of Department, Under-Head of First Division, Under-Head of Second Section, Division Officer). Arithmetic mean, intestinal deviation the research has reached a number of conclusions, the most prominent of which are: -
- There is an effect of
Abstract
The research aims to investigate the existence of correlations and influence between agricultural insurance risk management and economic development in the National Insurance Company with farmers, as agriculture is one of the leading branches of the national economy, ensuring food security and eliminating poverty to ensure sustainable ec
... Show MoreIn this work, the impact of different geomagnetic storm events on the plasma-sphere layer (ionosphere layer) over the northern and southern hemisphere regions was investigated during solar cycle 23. To grasp the influence of geomagnetic storms on the behavior and variation of the critical frequency parameter of the F2 ionospheric layer (foF2), five geomagnetic storms (classified as great, severe, and strong), with Disturbance storm time (Dst) values <-100 nT were chosen. Four stations located in different mid-latitude regions in northern and southern hemispheres were designated, the northern stations are: Millstone Hill (42.6° N, 288.50° W) and Rome (41.90° N, 12.50° E) and the southern stations are: Port Stanley (-51.60° S,
... Show MoreIn this study, Zizphus spina-christi leaf powder was applied for the adsorption of methyl orange. The effect of different operating parameters on the Batch Process adsorption was investigated such as solution pH (2-12), effect of contact time (0-60 min.), initial dye concentration (2-20 mg/L), effect of adsorbent dosage (0-4.5 g) and effect of temperature (20-50ᵒC). The results show a maximum removal rate and adsorption capacity (%R= 23.146, qe = 2.778 mg/g) at pH = 2 and equilibrium was reached at 40 min. The pseudo- second-order kinetics were found to be best fit for the removal process (R2 = 0.997). Different isotherm models (Langmuir, Freundlich, Dubini-Radushkevich,Temkin) were applied in this stud
... Show MoreA chemometric method, partial least squares regression (PLS) was applied for the simultaneous determination of piroxicam (PIR), naproxen (NAP), diclofenac sodium (DIC), and mefenamic acid (MEF) in synthetic mixtures and commercial formulations. The proposed method is based on the use of spectrophotometric data coupled with PLS multivariate calibration. The Spectra of drugs were recorded at concentrations in the linear range of 1.0 - 10 μg mL-1 for NAP and from 1.0 - 20 μg mL-1 for PIR, DIC, and MEF. 34 sets of mixtures were used for calibration and 10 sets of mixtures were used for validation in the wavelength range of 200 to 400 nm with the wavelength interval λ = 1 nm in methanol. This method has been used successfully to quant
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