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 research aims to know the role of strategic flexibility in achieving organizational effectiveness by studying the dimensions of strategic flexibility (capacity flexibility, resource flexibility, information flexibility, and coordination flexibility) on the dimensions of organization effectiveness (environmental adaptation, productivity and achieving goals) through an analytical study conducted in six directorates in the office of the Iraqi Ministry of Education.
The research problem was represented in the form of questions, the most prominent of which was "What is the role of strategic flexibility in achieving organization effectiveness?" The descriptive analytical approach was relied on in applying
... Show MoreIt highlights the importance of research through its focus on the assessment of tax for settling accounts Mmakhr medicines and annual statement controls and its role in determining the taxable income of the real tax Mmakhr drugs and achieve tax equity through tax settling accounts. The tax authority relies annual controls laid down by the tax settling accounts for Mmakhr medicines despite their inclusion bookkeeping business No. 2 system for the year 1985 average .ually this basis formulated hypothesis (that the adoption of the tax authority on annual controls in the tax settling accounts for Mmakhr medicine does not contribute in determining income taxable real tax for this Almmakr). the resulting search for a number of conclusions and
... Show Morethe digital public relations aim at make the workers getting the necessary information about the governmental institutions where they work and the enveronment surrounding them. it also tries to let the workers get the special knowlege of tthe publich relations and their jobs like the works of planning , arranging the active communication and executive skills needed in their writing , editing , special art skills for designing , production and technological skills to deal with the computer.
the problem of the research includes some questions as :
1- what are the uses achieved by degetal public relations workers at Iraqi universities (Baghdad, Mustansiriya, and Iraqi)
2- what are the tools used to apply digital public relations
The capital banking foundation stone upon which the bank in the practice of business activities, the more capital a good financial adequacy of the increased bank's ability to grant credit and expand the various activities and provide a safety element for depositors and other sources of funding to achieve profits and increase the trading volume of the shares, causing the rise the rate of return for the shares of banks and have the Central Bank as head of the banking system by issuing instructions capital increase banking, according to the requirements of economic development and increase gross domestic product by supporting investment projects that are financed through banks, the research aims to show the extent of the banks commitment to
... Show MoreRepresents a supervisory and oversight role of the Central Bank towards finding a sober banking sector, as the procedures , regulations and laws that the Central Bank insists on its implementation with the utmost precision, and that was to protect depositors and shareholders' class basis rights, but it is in the interest of the bank in the end, as it seeks to improve the performance of commercial banks and vaccinated against falling into the blunders, they also contribute to building a sober and stable banking sector and security contributes to the welfare and employment optimization of economic resources, and treatment of research (and the presence of banks decline in financial performance, according to financial performance indic
... Show MoreThe research aims at measuring the impact of visual media on the development of the tourism services sector, which is a field study for the public. It aims at determining the impact of visual media on tourism sector development, clarifying the concept of visual media and its functions and studying the role of media in the development of tourism culture among the public. For a sample of the employees of the University of Baghdad, consisting of (120) male and female. A questionnaire was prepared for this purpose consisting of (21) questions distributed to the sample. The data were analyzed and the hypotheses were tested using the statistical program spss to unload the results and calculate the frequencies, percentages and correlati
... Show MoreThe financial markets are one of the sectors whose data is characterized by continuous movement in most of the times and it is constantly changing, so it is difficult to predict its trends , and this leads to the need of methods , means and techniques for making decisions, and that pushes investors and analysts in the financial markets to use various and different methods in order to reach at predicting the movement of the direction of the financial markets. In order to reach the goal of making decisions in different investments, where the algorithm of the support vector machine and the CART regression tree algorithm are used to classify the stock data in order to determine
... Show Moreالخلاصة
تتناول هذه الورقة مخططات وسياسات الاستيطان في الضفة الغربية والقدس الشرقية منذ العام 1967، عبر سياسات قادها حزب العمل وأكملها حزب الليكود وكاديما وبقية الأحزاب الإسرائيلية، تلك السياسات التي استهدفت فرض السيطرة السياسية الكاملة على الأرض، وما نتج عن ذلك من سيطرة حصرية على الأرضوتقييد استخداماتها، ومحاصرة الوجود الفلسطيني والتضييق عليه، وتحويل مراكز ال
... Show MoreThis work evaluates the economic feasibility of various production scenarios for the Zubair reservoir in the Kifl oil field using cash flow and net present value (NPV) calculations. The Kifl field is an exploratory field that has not yet been developed or assessed economically. The first well was drilled in 1960, and three other wells were later drilled to assess the oil accumulation, so in this research, Different production scenarios were evaluated economically. These scenarios were proposed based on the reservoir model of the Zubair formation in the field. The research methodology used QUE$TOR software to estimate capital expenditures (CapEx) and operating expenditures (OpEx) based on field-level data, production prof
... Show MoreThe worsening of environmental problems has led to them being addressed by many entities, the most important of which are the top regulators. Federal Board of supreme audit Office is one of the most important regulators in Iraq. The problem of the research was the fundamental question of the extent to which the Federal Financial Supervisory Office was committed to implementing and exercising environmental control over the audited ones. The refore, the research was based on the main objective of questioning the role of the Federal Financial Supervisory Office in the exercise of environmental control and the compliance of those under its control, by identifying the antosai standards for environmental control, particularly the stand
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