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.
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Abstract : This research is concerned with studying the best type and method of irrigation as well as the best cultivated area to reduce the cost of producing dunums of wheat crop in Iraq , and was based on data taken from the Ministry of Planning / Central Statistical Organization About cost of wheat crop production for (12) Iraqi governorates except Kurdistan, Nineveh, Salah al-Din, Anbar) and the sample size (554) according to the cost survey carried out by the Ministry of Planning / Central Statistical Organization for 2017, The results of the research showed that there are significant statistical differences between production costs when using t
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A cumulative review with a systematic approach aimed to provide a comparison of studies’ investigating the possible impact of the active form of vitamin D3, calcitriol (CTL), on the tooth movement caused by orthodontic forces (OTM) by evaluating the quality of evidence, based on collating current data from animal model studies, in vivo cell culture studies, and human clinical trials. Methods: A strict systematic review protocol was applied following the application of the International Prospective Register of Systematic Reviews (PROSPERO). A structured search strategy, including main keywords, was defined during detailed search with the application of electronic database systems: Medline/Pubmed, EMBASE, Scopus, Web of Science, and
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Praise be to Allah. Praise be to Him. We seek refuge in Him. We seek forgiveness from him. We seek forgiveness from him.
And the disadvantages of our actions, of his hands
e
It is important, if not all, to pay tribute to God
Muhammad Abdo and Rasoulou, there is no way to deprive the nation of the weakness of God alone and not to share it
Which suffer from the Quran, and the loss of its borders, bad
The work did not work and did not improve
Do what they offer and delay the others, except by reference to this Koran and the extraction of treasures and secrets
And news.
The Great Quran Study
Lu Imito ordered each poisoned, and achieved several targets of
YEMYA: Knowing the secrets of the Grea
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<p>The current work investigated the combustion efficiency of biodiesel engines under diverse ratios of compression (15.5, 16.5, 17.5, and 18.5) and different biodiesel fuels produced from apricot oil, papaya oil, sunflower oil, and tomato seed oil. The combustion process of the biodiesel fuel inside the engine was simulated utilizing ANSYS Fluent v16 (CFD). On AV1 diesel engines (Kirloskar), numerical simulations were conducted at 1500 rpm. The outcomes of the simulation demonstrated that increasing the compression ratio (CR) led to increased peak temperature and pressures in the combustion chamber, as well as elevated levels of CO<sub>2</sub> and NO mass fractions and decreased CO emission values un
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The present work introduces, external morphological study of the leafhopper Neoalitarus
fenestratus Herrich-Schäeffer (Deltocephalinae:Oposiini), particularly the male genitalia
which were dissected and illustrated.
The research aims at clarifying the relationship between innovative marketing skills and broad recommendation as a vital and important issue for organizations in general and service organizations in particular to demonstrate how innovative marketing skills contribute to broad adoption and to determine the relationship between interdependence and the impact of innovative marketing skills on the broad recommendation. Some questions are posed by the research problem. Is there a clear awareness among individuals in the company about the concept of marketing marketing skills and how do innovative marketing skills affect the broad recommendation of the surveyed company? How innovative marketing skills relate to the broad recommendation
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In this study, a mathematical model is presented to study the chemisorption of two interacting atoms on solid surface in the presence of laser field. Our mathematical model is based on the occupation numbers formula that depends on the laser field which we derived according to Anderson model for single atom adsorbed on solid surface. Occupation numbers formula and chemisorption energy formula are derived for two interacting atoms (as a diatomic molecule) as they approach to the surface taking into account the correlation effects on each atom and between atoms. This model is characterized by obvious dependence of all relations on the system variables and the laser field characteristics which gives precise description for the molecule –
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