The BEK family of flows have many important practical applications such as centrifugal pumps, steam turbines, turbo-machinery and rotor-stator devices. The Bödewadt, Ekman and von Kármán flows are particular cases within this family. The convective instability of the BEK family of rotating boundary-layer flows has been considered for generalised Newtonian fluids, power-law and Carreau fluids. A linear stability analysis is conducted using a Chebyshev collocation method in order to investigate the effect of shear-thinning and shear-thickening fluids for generalised Newtonian fluids on the convective Type I (inviscid crossflow) and Type II (viscous streamline curvature) modes of instability. The results reveal that shear-thinning power-law fluids have a universal stabilising effect across the entire BEK family of flows. However, the convective instability characteristics for the shear-thinning and shear-thickening Carreau fluids are affected by the value of the relaxation parameter k. The results reveal that Shear-thinning Carreau fluids have a small destabilising effect, while shear -thickening fluids have a slight stabilising effect on the Type I and Type II mode for the BEK family of flows when k =100. On the other hand, shear-thinning and shear-thickening Carreau fluids are found to have stabilising and destabilising effect, respectively for optimal relaxation value ko. The results are presented in terms of neutral curves and growth rates. Furthermore, an energy analysis is presented to gain insight into the underlying physical mechanisms behind the stabilising effects of generalized Newtonian fluids. In conclusion, the use of shear-thinning power-law and Carreau fluids with optimal value ko can be recommended to reduce skin-friction drag in enclosed rotor-stator devices for the entire BEK family of flows.
Objectives: To determine the impact of the household hazardous waste’s aspects upon the environment
pollution .and to identify the relationship between the households’ demographic characteristics and the aspects
of household hazardous waste.
Methodology: A descriptive study is conducted between December 14th 2004 to October 20th 2005that uses of
an assessment tool. A probability (simple random sampling) of (336) principal’s households which is selected
from the zones around the (14) primary health care centers as focal points, (8) in the urban and (6) in the rural
areas of Baghdad Governorate. After reliability and validity were determined Data are collected through the use
of an assessment tool that is consist
In the name of of Allah the Merciful
Praise be to God, and blessings and peace be upon the Messenger of God, Muhammad, and upon his family and his family and peace, and after:
The honor of every knowledge of honor is related to it, and since the science of interpretation is related to the Book of God Almighty; it is considered one of the most noble and longest of sciences, and this science began long ago as the early ages of Islam have expanded the Islamic state, and people entered the religion of God in cohorts, and the mixture mixed In tongues, and people did not know much about the meanings of the Qur’an, so the need for authorship in this great knowledge was severe, and pe
This study attempts to provide an approach analysis for the news, depending on the bases and principles which conceptuality semiotic researchers of this field first of them «A. J. Gremas» for the theory of «narrative discourse analysis», to more clarify we tried to apply it on a published press- news, to concludes the most important steps and methods that are necessary to follows gain more understanding of the press- news.
Theatrical techniques took upon themselves the responsibility of building and organizing the theatrical form for the various forms of performances, and it was the important tool that the show makers could rely on in carrying out the various works at the audio-visual level, and lighting is one of the most important elements of the visual formation of the image in the show, as it is related to the visual process and what it can achieve in operations The contrast that constitutes the aesthetic and intellectual values of the theatrical show, especially since the process of adjusting the element of time and the timings for receiving or delivering, moving, and the movement of the actor is what can determine the rhythm of the scene, which in it
... Show MoreThe influx of Arab Qahtani and Nizari tribes continued to the countries of Baluchistan and the Levant in pre-Islamic times until the Levant became open to the Arab-Islamic tide during the first century AH. The Islamic Orient until the early Islamic Arab Army reached the western borders of China. What we will see in the folds of the search.
The folkloric games widely considered as expressional forms of nations culture and their environment which can be an important element in Iraqi child theatre shows. For its moral and habits relation to the needs of children which present an effective mean to preserve the true identity of the society character and moral. The research concluded many topics considering the importance of folkloric games in the Iraqi child theatre, the first chapter studied the problem , the necessity , the aim of the research to clarify the importance of folkloric games in Iraqi child theatre, the second chapter is the theoretical part of the research that studied the concept of folkloric games and its implementation in Iraqi child theatre . the third chapte
... Show Moreالأحكام القانونية للجرف القاري في القانون الدولي
God sent the Prophet Muhammad as a teacher and promising harbinger {that is sent to the illiterate messenger reciting to them His signs and purifies them and teaches them the Book and Wisdom} [Friday: 2]; the wisdom of Baos Prophet him peace be and am back to teach people, - Education and therefore his life was very rich educational tactics And has passed the Prophet in different circumstances and conditions that can be experienced by a teacher or educator in any time, anywhere; there is no case of going through the educator or teacher only finds the same or similar or likened to, or close to it in the life of the Prophet peace be upon him Prophet has lived God's peace be upon his strengths and weaknesses, victory and defeat, he lived or
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