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.
This paper studies the adaptive coded modulation for coded OFDM system using punctured convolutional code, channel estimation, equalization and SNR estimation. The channel estimation based on block type pilot arrangement is performed by sending pilots at every sub carrier and using this estimation for a specific number of following symbols. Signal to noise ratio is estimated at receiver and then transmitted to the transmitter through feedback channel ,the transmitter according to the estimated SNR select appropriate modulation scheme and coding rate which maintain constant bit error rate
lower than the requested BER. Simulation results show that better performance is confirmed for target bit error rate (BER) of (10-3) as compared to c
Rotating fan shaft system was investigated experimentally and theoretically to study its dynamic performance. The type of oil used for the bearing was taken in consideration during the experimental program .Three types of oil were used, SAE 40, SAE 50 and degraded oil. During the experiments, the fan blades stagger angle was changed through angles (20˚, 30˚, 40˚, and 50˚). The shaft rotational speed also changed in the range of (0-3000 rpm). All these parameters have investigated for two cases (balanced and unbalanced fan). The performance parameters of the fan were found experimentally by measuring the fan, volume flow rate, Reynolds and Strouhal numbers, efficiency and pressure head. Analytical part was also represented to prepare
... Show MoreThe frog has a highly developed nervous system. It consists of a brain, a spinal cord and nerves. The brain is the only center for the control of all vital activities as it receives impulses from different parts of the body through sensory nerves and issues orders through motor fibers to different parts of the body for appropriate action. The Aims of studyis general morphological structural of the brain and spinal cord in the Iraqi frog Rana ridibunda ridibunda. The brains of twenty of frogs belonging to class Amphibia were studied using conventional techniques of dissecting microscopy. All samples were sacrificed and anesthetized and then they were removed completely from the neurocranium, cranial, sensory nerves and the meninges and trans
... Show MoreThis study aims to know the relationship between the birth order and lifestyles among a sample of adolescent students. The sample of the study consisted of (200) students selected from the governmental schools in the Directorate of Education of Qabatiya, in the second semester of the academic year 2020/2021. The results of the study have revealed that the most common lifestyles among the sample of the study are represented by: (the belonging) style, (the submissive) style, (the avenger) style, (the pampered) style, respectively. The study has also found that there are statistically significant differences in the lifestyles of: (the victim, the domineering, the avenger, and the harmful) which are ascribed to the gender variable. Mor
... Show MoreThe present study aimed to identify the exact location and its relation to cognitive
method (risk_caution) to university students. The sample consisted of (300) students who
were chosen randomly and equally. The study results indicated that students possess an
internal exact location and they also use risk cognitive method. The study also indicated that
there is a prophesies which is an exact location for others to reach to caution cognitive
method. Depending on these results, the study recommended to benefit from the results of the
study variables and from the measurement of the exact location and method of cognitive
(risk_caution) to identify male and female students and especially by consulting units at
college
It is well known that the art of theater is based on multiple elements come in the forefront of Representative and his work, and must be of such a representative of the kits help him to complete his work and take it out the image that aspires to it is team work, and these supplies are in the two main axes:First: Internal supplies which runs from the imagination through the focusing and memory Representative and adapts to situations and positions and others.The second is a foreign supplies, which starts from his words and gestures and his movement and his voice, which is the need to requirements help to maturation and completion of this aspect, including the lighting, costumes, decor, make-up, is the role of make-up theater and its import
... Show MoreAround 65 million individuals suffer from epilepsy worldwide, and when it is not properly treated, it is linked to higher rates of physical harm and mortality. Due to the requirement for long‐term therapy and the side effects of many medications, medication compliance is a significant issue. The purpose of this review was to summarize the findings of previous studies examining the quality of life (QOL), adherence, patient education, and medication knowledge, as well as the impact of a pharmacist‐led educational intervention. Additionally, to find out if these studies benefit epileptic patients, to find the appropriate method used to help them in all aspects of their lives, and to use these in future studies. A systematic and comprehensi
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