In this paper, the problem of developing turbulent flow in rectangular duct is investigated by obtaining numerical results of the velocity profiles in duct by using large eddy simulation model in two dimensions with different Reynolds numbers, filter equations and mesh sizes. Reynolds numbers range from (11,000) to (110,000) for velocities (1 m/sec) to (50 m/sec) with (56×56), (76×76) and (96×96) mesh sizes with different filter equations. The numerical results of the large eddy simulation model are compared with k-ε model and analytic velocity distribution and validated with experimental data of other researcher. The large eddy simulation model has a good agreement with experimental data for high Reynolds number with the first, second and third mesh sizes and the agreement increase near the wall of the duct. The percentage error for the large eddy simulation model with experimental data of the (56×56) mesh size is less than 18 % and for the (76×76) mesh size is also less than 17% and for the (96×96) mesh size is less than 16 %. The large eddy simulation model show high stability and do not need extra differential equation like the k-ε model and a great saving in time and computer memory was achieved.
Abstract
Due to the lack of previous statistical study of the behavior of payments, specifically health insurance, which represents the largest proportion of payments in the general insurance companies in Iraq, this study was selected and applied in the Iraqi insurance company.
In order to find the convenient model representing the health insurance payments, we initially detected two probability models by using (Easy Fit) software:
First, a single Lognormal for the whole sample and the other is a Compound Weibull for the two Sub samples (small payments and large payments), and we focused on the compoun
... Show MoreThis research aims to investigate the impacts of Quranic readings on the meanings of antonyms in the Quran, with considering the practical aspects that clarify them. The importance of this topic lies in clarifying the importance of the science of Qiraʼat, its great value and its high status. Moreover, this research sheds light on the relationship between Quranic readings and the antonyms words, following the descriptive approach in the study. The research has found several findings, the most prominent of which was: antonyms are linguistic phenomena that are proven to occur in Quranic readings, so each reading deliver a meaning that is opposite to the meaning learned from the other reading.In addition, Quranic readings are considered as
... Show MoreThe present paper studies the use of adjectives in Shakespeare's Sonnets (4, 5, 6, & 9), which are chosen randomly, on the three levels: grammar, lexis and conversation. It tackles adjectives as a literary term with presenting their forms and functions. The presentation is done according to the themes, their forms and functions in conversation, the adjectives are shown in this paper as for their forms, frequency and meanings in the sonnets and their effects on studying. The analysis is done according to Quirk et al. (1985) and Quirk and Greenbaum (1973). Then, all adjectives have been calculated in the sonnets. The results of the analysis have shown that compound adjectives which occurred (31) are used more than the Suffixation
... Show MoreThe concept of equality in Islamic thought emanates from the unity of human entity that does not breach the concept of equality in itself and it should take differentiation among people as means for development and growth not as excuse for injustice and discrimination. Islamic thought has left all the prevailing norms of differentiation such as (weakness and strength, economic and social position, gender, color, and social class). Islamic thought has underscored the quality of people of different race, race, color, and language which was not familiar in those civilizations before the emergence of Islam such as (Egyptian, Persian, roman civilization). It was common to divide people into different social classes. The aim of Islam is to kee
... Show MoreAn essential element in English as a foreign language (EFL) learning is vocabulary. There is a big emphasis on learning the new words' meaning from the books or inside classrooms. Also, it is a major part of language teaching as well as being fundamental to the learner but there is a big challenge in vocabulary instruction due to the weak confidence by teachers in selecting the suitable practice in teaching vocabulary or they sometimes unable to specify a suitable time for it during the teaching process. The major aim of this study is to investigate the value of posters in vocabulary learning on the 2nd grade students at Halemat Alsaadia High School in Baghdad – Iraq. It hypothesized that there are no statistically significant differences
... Show MoreA new type of the connected domination parameters called tadpole domination number of a graph is introduced. Tadpole domination number for some standard graphs is determined, and some bounds for this number are obtained. Additionally, a new graph, finite, simple, undirected and connected, is introduced named weaver graph. Tadpole domination is calculated for this graph with other families of graphs.
The primary goal of the study is to practise some systematic strategies for foreign language instruction despite the fact that no single approach to language classroom instruction is inherently superior to others; instead the choice of an approach should be determined by the teacher, students, the subject matter, and the situation. The paper adopts certain strategies which may assist EFL teachers to excel in their work and continue their professional development. Hence, it is intended for language teachers who understand the value of good teaching and like to produce academically successful students. The study could also help college student teachers to acquire new strategies in order not only to succeed but also to excel in their learni
... Show MoreThis research deals with a disease of the diseases our Muslim society, which works in the
body operate deadly epidemics in the bodies and of bodies, but it is extravagant; has spread
and rampant in our uncle everything which threatens significant damage in this life and the
afterlife, as well as that it shows that Alasirafla limited to extravagant in wasting money and
with this blessing should not have, and not be used as created him .
Excessive linked to all aspects of life, physical and moral it has many pictures and various
forms, came at the forefront of research and five sections:
The first topic: the meaning of truth and extravagant.
The second topic: Photos extravagant reprehensible contained in the Koran.<