The aim of this research is to study the factors affecting drag coefficient (C d ) in
non-Newtonian fluids which are the rheological properties ,concentrations of non-
Newtonian fluids, particle shape, size and the density difference between particle and
fluid .Also this study shows drag coefficient (C d ) and particle Reynolds' number (Re
P ) relationship and the effect of rheological properties on this relationship.
An experimental apparatus was designed and built, which consists of Perspex pipe
of length of 160 cm. and inside diameter of 7.8 cm. to calculate the settling velocity,
also electronic circuit was designed to calculate the falling time of particles through
fluid.
Two types of solid particles were used; glass spheres and crushed rocks as
irregularly shaped particles with different diameters and compared with each other.
The concept of equivalent spherical diameter (D S ) was used to calculate the
diameters of irregularly shaped particles.
The flow behavior for Non-Newtonian fluids was represented by Power-Law model.
Two types of polymers were used, Carboxy Methyl Cellulose CMC with
concentrations of (3.71, 5, 15 and 17.5) g/l and polyacrylamide with concentrations of
(2, 4 and 6) g/l.
The results showed that the drag coefficient decreased with increasing settling
velocity and particle diameters and sizes; and increased as fluid become far from
Newtonian behavior and concentrations and the density difference between particle
and fluid.
The results also showed that the rheological properties of Non-Newtonian fluids
have a great effect on the drag coefficient and particle Reynolds number relationship,
especially in laminar-slip regime and decreases or vanishes at transition and turbulentslip
regimes.
New correlations were obtained which relates drag coefficient with concentrations
of polymers and with flow behavior indices for spherical and irregular shaped
particles in Carboxy Methyl Cellulose CMC and polyacrylamide solutions.
This study aims to explain the role of green target costing technique in improving the relationship with suppliers in a sample of industrial companies listed on the Iraq Stock Exchange. The descriptive analytical approach was used, where a questionnaire was designed that included a set of questions that were directed to a sample of 84 individuals including production managers, finance managers, quality managers, and purchasing managers in these companies. The study uses some statistical analyzes such as correlation analysis and regression analysis to analyze the questionnaires. The study finds a positive impact of the green target costing technique on improving the relationship with suppliers. The results indicate that the relation
... Show MoreThe story of Peter Pan is considered one of the immortal tales that has been read and watched over many generations, and many of the events of the story have been changed over time to suit the time in which it will be read, and this is what will be discussed in this paper in addition to identifying the writer‟s life and the extent influence on Peter Pan. Time in the story of Peter Pan is particularly important because the story changes its events during that time in proportion to the era in which it is in, as there have been many changes in all events and characters to suit the reader. Through this paper, the researcher will come up with the life of the author and how his life affected Peter Pan‟s story, then a small summary of the stor
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The photoconductivity and its dependence on light intensity have been investigated in a-Ge20Se80 thin films as a function of temperature between (293–323)K. The result showed that the photoconductivity and photosensitivity increase with increase of annealing temperature. This behavior is interpreted in terms of the dispersive diffusion –controlled recombination of localized electrons and holes.
We deal with this essay about religious mystic poetry of Atika Al-
Khazraji. We think she imitates Rabia Al-Adawiyya. We do not deny that our
poetess lived in a conservative society although she lives in reality a liberal
life, so she tries to satisfy her society. In fact these mystic poems are pure
love. Poems in men.
This double standard behavior is quite clear in women’s poems in the
Arab world of this era.
This study was conducted to examine the anatomical aspects of
(2)
We have chosen the subject of the research (the letters at Ibn Jinnie in the lexicon of the tongue of the Arabs) in order to know the opinion of Ibn Jinnie in this range of words and compare them with the opinions of scientists who preceded him to know the personality of this linguistic world.
(4)
(3)
Understanding of in-situ stress profiles and orientations plays a vital role in designing a successful hydraulic fracturing treatment. This paper is an attempet to examine the effect of lithology and in situ stress on geometery of hydraulic fractures. A hydraulic fracturing design simulator software called FracproPT with various capabilities for designing most of hydraulic fracture was used for simulate and optimize the hydraulic fracturing. For studying purpose, three different cases of stress gradient contrast between different formations are considered in this study (0.4, 0.5 and 0.75 psi/ft). The results obtained from the simulator showed that lithologies surrounding the pay zone have an effect on the fracture
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