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.
The current research focuses on the extent to which the strategic orientation(entrepreneurial orientation, customer orientation, technology orientation, learning orientation, and investment orientation) affects the learning organization (building common vision, systemic thinking, personal dominance, mental models, team learning)The first hypothesis to test the connection relation between research variables and The second hypothesis was to test the relationship between these variables. In order to ascertain the validity of the hypotheses, the research was based on a questionnaire questionnaire prepared according to a number of In addition to building a fifth sub-variable for the strategic orientation (investment orientation) based
... Show MoreEstimation of the unknown parameters in 2-D sinusoidal signal model can be considered as important and difficult problem. Due to the difficulty to find estimate of all the parameters of this type of models at the same time, we propose sequential non-liner least squares method and sequential robust M method after their development through the use of sequential approach in the estimate suggested by Prasad et al to estimate unknown frequencies and amplitudes for the 2-D sinusoidal compounds but depending on Downhill Simplex Algorithm in solving non-linear equations for the purpose of obtaining non-linear parameters estimation which represents frequencies and then use of least squares formula to estimate
... Show MoreThe aim of present study to investigate the effect of Coraindrum sativum leaves extract on reproductive activity of male albino mice .Thirty male mice with age of 80-100 day and weight between 25-30 g were divided into three groups: group 1 (untreated), group 2 and 3 were administrated orally for 30 days with aqueous extract of Coraindrum sativum leaves at dose 125 and 250mg/kg.b.w. respectively. The following parameters were evaluated: serum testosterone levels, testes weights, sperm characteristics [motility, viability, spermatozoa, morphology and concentration] and histology changes of the testis. The results showed that the treatment caused highly significant degrease (P<0.01) in testosterone levels and the weight of testes assoc
... Show MoreThe banking sector has a significant impact on the economic growth of the country, and the importance of this sector must assess its financial performance from time to time, to measure the situation related to money for each bank and how to put the supervision of the efficiency of the full. The research aims at evaluating the financial performance according to the elements of the CAMELS model, which including capital adequacy, asset quality, management efficiency, profitability, liquidity, and market risk sensitivity. The research included the study of Al-Mansour Investment Bank during the period from 2014 to 2018. The base capital ratio was used to total assets to measure capital adequacy The proportion of investments to total a
... Show MoreAn increasing trend to use probiotic and study their effects on the pathogens has been conductor where they are defined as live micro-organisms that give a health benefit to the host when ingested in sufficient quantities, including the yeast Saccharomyces boulardii In addition research show that a magnetic field (MF) has a biological effect. This study aims to investigate the effects of magnetic field on the inhibitory action of Saccharomyces boulardii against bacteria isolated from urinary tract infection, Study the sensitivity of bacterial isolates to antibiotics after diagnosis by microscopic, Cultural and biochemical examinations as well as Api20 E examinations were used gram negative bacteria , Most isolates were resistant to an
... Show MoreAbstractIn the field of construction materials the glass reinforced mortar and Styrene Butadiene mortar are modern composite materials. This study experimentally investigated the effect of addition of randomly dispersed glass fibers and layered glass fibers on density and compressive strength of mortar with and without the presence of Styrene Butadiene Rubber (SBR). Mixtures of 1:2 cement/sand ratio and 0.5 water/cement ratio were prepared for making mortar. The glass fibers were added by two manners, layers and random with weight percentages of (0.54, 0.76, 1.1 and 1.42). The specimens were divided into two series: glass-fiber reinforced mortar without SBR and glass-fiber reinforced mortar with 7% SBR of mixture water. All s
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Background: Heat-cured poly (methyl methacrylate) the principal material for the fabrication of denture base have a relatively poor mechanical properties. The aim of this study was to investigate the effect of glass flakes used as reinforcement on the surface hardness and surface roughness of the heat-processed acrylic resin material. Material and method: Glass flakes (product code: GF002) pretreated with silane coupling agent were added to Triplex® denture base powder using different concentrations. A total of 100 specimens of similar dimensions (65 x 10 x 2.5) mm were prepared, subdivided into 2 main groups of 50 specimens for each of the study tests. Ten specimens for the control group and 40 specimens for each of the experimental gro
... Show MoreThe present study was conducted to examine toxicological effects of copper sulfate (Cu) in common carp fish (Cyprinus carpio L.). The LC50 (median lethal concentrations) of copper on Cyprinus carpio were 3.64, 3.36, 3.04, 2.65 mg/L respectively. In general, behavioral responses of the fishes exposed to copper included uncontrolled swimming, erratic movements, loss of balance, swam near the water surface with sudden jerky movements. Haematological parameters such, red blood cells (RBC), white blood cells (WBC), haemoglobin (Hb), Packed cell volume (PCV), mean cell volume (MCV) mean cell haemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) were studied. The obtained results indicated that the (RBC) and (WBC) have increas
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