Applying a well-performing heat exchanger is an efficient way to fortify the relatively low thermal response of phase-change materials (PCMs), which have broad application prospects in the fields of thermal management and energy storage. In this study, an improved PCM melting and solidification in corrugated (zigzag) plate heat exchanger are numerically examined compared with smooth (flat) plate heat exchanger in both horizontal and vertical positions. The effects of the channel width (0.5 W, W, and 2 W) and the airflow temperature (318 K, 323 K, and 328 K) are exclusively studied and reported. The results reveal the much better performance of the horizontal corrugated configuration compared with the smooth channel during both melting and solidification modes. It is found that the melting rate is about 8% faster, and the average temperature is 4 K higher in the corrugated region compared with the smooth region because of the large heat-exchange surface area, which facilitates higher rates of heat transfer into the PCM channel. In addition to the higher performance, a more compact unit can be achieved using the corrugated system. Moreover, applying the half-width PCM channel accelerates the melting rate by eight times compared to the double-width channel. Meanwhile, applying thicker channels provides faster solidification rates. The melting rate is proportional to the airflow temperature. The PCM melts within 274 s when the airflow temperature is 328 K. However, the melting time increases to 460 s for the airflow temperature of 308 K. Moreover, the PCM solidifies in 250 s and 405 s in the cases of 318 K and 328 K airflow temperatures, respectively.
The problem of multi assembly line balancing appears as one of the most prominent and complex type of problem. The research problem of this dissertation is concerned with choosing the suitable method that includes the nature of the processes of the multi assembly type of the sewing line at factory no. (7). The State Company for Leather Manufacturing. The sewing line currently suffers from idle times at work stations which resulted in low production levels that do not meet the production plans. The authors have devised a flexible simulation model which uses the uniform distribution to generate task time for each shoe type produced by the factory. The simulation of the multi assembly line was based on assigni
... Show MoreThe present research is descriptive and analytical by nature; it practically presents the method of implementing the standard pattern in an unconventional way using the bias-cut line. The study aims at investigating the variables of bias-cut and their suitability for fitting large-shaped Iraqi ladies. It also aims at exploring the artistic and innovative features of the bias-cut. Therefore, one needs to understand the rules and basics of clothing and the nature of the body to reach the maximum degree of control.Consequently, the study is to answer the following questions: What is the effectiveness of tailoring on the bias-cut in fitting a standard template of a large-shaped Iraqi ladies? Is it possible to obtain from the offered possibil
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Praise be to Allah, the Lord of the Worlds, the best prayer and the best prayer, on our master Muhammad, and on his pure God, and his companions and the faithful, and who followed them by charity to the day of religion. This relationship between emphasis, is a sincere, and this harmony, such as the relationship between water, and the green, but it is good, but, with greenery, it is better, and as well as alone, is a beautiful view, but the most beautiful, with the most beautiful. From here he was starting on myself in writing the fundamentalist research of jurisprudence, to show the depth of this interconnection. The doctrine as a new term, then the taj al-Din al-Suobki came after three centuries, and a
... Show MoreThe theme of love has been and still is the interest of authors and writers for it is closely related to people’s lives. That great passion has helped them express genuine thoughts pertinent to that theme that has given rise to many debates, some are vague and others controversial. In his (strait is the gate), (La Porte étroite), André Gide has sought to shed light on his characters perspective of love and its relationship with sacredness and divine happiness. Indeed these characters have found often themselves restrained, chained and exhausted, by tough religious commands that have imposed on them spiritual commitments and duties too hard to break.
André Gide has revealed a protestant deviation from the perfection theme tha
... Show MoreAmong several separation processes, the air flotation distinguish as remarkably high potential separation process related to its high separation efficiency and throughput, energy-efficient, simple process, cost-effective, applicable to a wide range of oily wastewater and no by-products. The current study aimed to investigate the effect of the type and concentration of surfactant on the stability of oil-water emulsion and efficiency of the separation process. For this purpose, three types of surfactant where used (anionic SDS, mixed nonionic Span 85/Tween 80, and cationic CTAB). The results demonstrated that the Span 85/Tween 80 surfactant has the best stability, and it increases with the surfactant concentration augmentation. The removal ef
... Show MoreBackground: With the increasing demands for adult orthodontics, a growing need arises to bond attachments to porcelain surfaces. Optimal adhesion to porcelain surface should allow orthodontic treatment without bond failure but not jeopardize porcelain integrity after debonding.The present study was carried out to compare the shear bond strength of metal bracket bonded to porcelain surface prepared by two mechanical treatments and by using different etching systems (Hydrofluoric acid 9% and acidulated phosphate fluoride 1.23%). Materials and Methods: The samples were comprised of 60 models (28mm *15mm*28mm) of metal fused to porcelain (feldspathic porcelain). They were divided as the following: group I (control): the porcelain surface left u
... Show MoreNo country in the world has an ancient heritage of its own. It represents the product of the civilizations left behind by previous eras. It represents the development of urban life and its capital of the interest of its people in the field of construction and reconstruction. The urban heritage and its associated arts may seem to be a material heritage at first glance, but it is not free from the spiritual side. Therefore, the nations in different parts of the earth cherish it and care for it with all due diligence, because it mixes with its history, memories and emotions.
This research discusses the use of local environment materials in the production of urban fabric constituents. I
RESUMEN
Una joven cuenta cómo, en plena noche, aprovechando la tranquilidad de esa hora, sale a escondidas de su casa y va a reunirse con su enamorado. Envuelta en la oscuridad, se deja dirigir por la luz de su propio amor hasta el lugar de la cita, donde la pasión de los amantes culmina. A continuación, relajados por la brisa nocturna, los amantes se adormecen, primero, el amado velado por la amada, por último, ella misma.
Amor entre dos enamorados. Unión mística de alma y Dios , aunque , de hecho , podría servirnos de clara exposición temática el subtitulo con que el poema suele publicarse en la tradición , tanto manuscrita como impresa : Canciones del alma que se goza d
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