This study examines experimentally the performance of a horizontal triple concentric tube heat exchanger TCTHE made of copper metal using water as cooling fluid and oil-40 as hot fluid. Hot fluid enters the inner annular tube of the TCTHE in a direction at a temperature of 50, 60 and 70 oC and a flow rate of 20 l/hr. On the other hand, the cooling fluid enters the inner tube and the outer annular tube in the reverse direction (counter current flow) at a temperature of 25 oC and flow rates of 10, 15, 20, 25, 30 and 35 l/hr. The TCTHE is composed of three copper tubes with outer diameters of 34.925 mm, 22.25 mm, and 9.525 mm, and thicknesses of 1.27 mm, 1.143 mm, and 0.762 mm, respectively. TCTHE tube's length was 670 mm. Nusselt number, overall heat transfer coefficient, convective heat transfer coefficient (CHTC), friction factor and pressure drop were measured from the obtained experimental results and plotted in graphs against Reynold number and volumetric flow rate of water. These parameters appeared good results in the cooling process. Nusselt numbers increased linearly with DIW flow rate for both C1 and C2 reaching maximum values of 38.25 and 14.64 respectively. CHTC increased linearly with the DIW flow rate for both C1 and C2 reaching maximum values of 2934.3 and 871.7 respectively. Overall heat transfer coefficient of DIW reached maximum values of 296.36 and 251.4 at 35 l/hr for C1 and C2, respectively. Friction factor DIW in C1 and C2 decreased with the volumetric flow rate increases, reaching minimum values of 0.04 and 0.25 respectively. Pressure drop of DIW increased linearly with flow rate reaching maximum values of 81.4 and 4.31 for C1 and C2 respectively. This in turn leads to reduced TCTHE length and size leading to a decrease in the construction cost of the heat exchanger.
Abstract
This study aims to find the relationships between social capital (social network, social trust, shared goals) and knowledge sharing (knowledge Donating, knowledge collecting) as independent variables and their impact on improving the quality of educational services (academic staffs quality, Quality of teaching methods and study curriculums). This research is an important, because it attempts to identify the relationship between social capital and the knowledge sharing and their effect on improving the quality of educational service for universities. The study problem was determined in several questions related to the nature of the correlation relationship - the impact between the different independent variables (
... Show MoreThis research asks what are negative social behaviours in the Kurdistan Region of Iraq (KRI) raised by the talk shows on the (NRT) channel? Furthermore, it aims to identify the most significant themes addressed by talk shows on the (NRT) channel regarding negative social behaviours in the KRI by using the content analysis approach through non-random purposive sampling to understand the dialogue contents that dealt with this subject. This study has reached a set of results: through its talk shows, the (NRT) channel attempts to create a media vision about the spread of negative social behaviours in the KRI and stand up to the dangers associated with these behaviours. At the same time, those programs tried to marginalize the behaviours that
... Show MoreThis study aimed at examining the role played by the media outlets during the coverage
of the presidential election campaigns 2020 of the United States of America.
The analytical study used through a partial inventory of the research community
for almost three months from the announcement of the candidates’ names by
the major parties on August 13 to November 6، which is the official election day in
the U.S. National Public Radio Station (NPR) to achieve the objectives of the study.
The study reached a number of conclusions related to the contents، methods and
sources of media coverage of the election campaigns of the 2020 U.S. at the mentioned
station، where the researcher proposed a number of recommendations
The research (Comic Scene Construction between Dramatic Situation and Acting Performance in Feature Film) has been divided into the following: the methodological framework which consists of the problem of the research: how to construct the comic scene between the dramatic situation and acting performance in the feature film. The research importance and aims are: identifying how to construct the comic scene between the dramatic situation and acting performance in the feature film. The limits of the research are also stated.
The research is divided into three sections: the first is the comic situation and the Aristotelian discourse in which the comic situation is clarified starting from the Aristotelian discourse. The second section: me
Researchers classified deconstruction as a strategy concerned with reading the philosophical, literary, artistic and critical texts according to (construction and deconstruction) binarism, which is an applied procedural space that calls for researching the layers of meaning and its non-closure. It establishes reversals in the text level. The center changes into a margin and vice versa. Thus the two researchers sought to study the deconstruction strategy and its work in the theatre field, that deconstruction is considered one of the most important modern currents that actively inters in reading the theatre show. The research studies the procedure of the construction and deconstruction of the Iraqi theatre actor reg
... Show MoreThis experiment was conducted to study the effect of injecting hatching eggs into a flock of broiler aged mothers with different concentrations of the alcoholic extract of Moringa oleifera powder on productive performance of broilers during the period of rearing of 35 days. The study included two experiments for a period at 2/10/2021 to 28/11/2021, where eggs were injected into the Mustafa Poultry Hatchery/ Wasit Governorate- Aziziyah District. A 400 hatching eggs of 308 Ross mothers of modern broilers used at age of 48 week, eggs of average weight 66 ± 1 g/egg were collected in same day then stored for two days. A quarter of treatments were randomly distributed with 100 eggs for each treatment.
... Show MoreAbstract Physical requirements are an important priority for the development of football gymnastics coaches because the nature of performance is interconnected and interconnected in terms of the player's duties in the match. In the gameplay situations, the player must perform the skill with strength and speed coupled with accuracy and the reactions of the colleague and competitor alike, which represents the normal reality of the football gymnasium Skilled exercises are one of the most suitable technical side exercises as they are built according to the components of the skill requirements of the game and the nature of its performance, which appear on the gro
... Show MoreSteps were taken to obtain the Kojic acid crystals from local fungal isolation A. flavus WJF81 by separating the fermentation products from the fungus mycelium from the production plant at the centrifuge at a speed of 5000 cycles for 10 minutes. The extraction was followed by ethyl acetate then supernatant concentrate by using rotary evaporator, and dried with heat oven 37ºC. Long, yellowish, pristine acid crystals were obtained that examined the optical microscope with a magnification force of 10x and 40x. The melting point of kojic acid was determined between 152.9-153.5 °C Results of the diagnosis of Kojic acid by applying High pressure liquid chromatography HPLC technique showed that the acid was at one peak, which was close to the
... Show MoreThe increasing use of polymeric materials in the daily life, leads to challenges in the processing industry to deliver high performance materials with affordable terms. However, new processing techniques lead to high costs. In order to reduce processing costs it is necessary to understand the non-Newtonian behavior of the polymers in their molten state to be able to simulate the processes before the construction of the plants starts. Here the shear thinning behavior of the viscosity of polymeric melts is essential. Thus, this paper deals with the experimental investigation of the thermo-rheological behavior of the viscosity of one of the most used polymers (Polypropylene) over a wide range of temperatures and shear rates. Furthermo
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