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.
Linear programming currently occupies a prominent position in various fields and has wide applications, as its importance lies in being a means of studying the behavior of a large number of systems as well. It is also the simplest and easiest type of models that can be created to address industrial, commercial, military and other dilemmas. Through which to obtain the optimal quantitative value. In this research, we dealt with the post optimality solution, or what is known as sensitivity analysis, using the principle of shadow prices. The scientific solution to any problem is not a complete solution once the optimal solution is reached. Any change in the values of the model constants or what is known as the inputs of the model that will chan
... Show MoreIn this study, the effects of different loading doses of cerium in the prepared NaY zeolite from Iraqi kaolin were investigated. Al-Duara refinery atmospheric residue fluid catalytic cracking was selected as palpation reaction for testing the catalytic activity of cerium loading NaY zeolite. The insertion of cerium in NaY zeolites has been synthesized by simple ion exchange methods. Three samples of modified zeolite Y have been obtained by replacing the sodium ions in the original sample with cerium and the weight percent added are 0.35, 0.64, and 1.06 respectively. The effects of cerium loading to zeolite Y in different weight percent on the cracking catalysts were studied by employing a laboratory fluidized
... Show MoreThis study has been conducted to know the level of microbial ( bacteria and fungi) contamination in 5 types of biscuits from local markets of Baghdad city. Fifty samples (ten sample for each kind of biscuit) were studed,Two are local,others are Iranian,Turkish,and Holandies. The following results have been achieved :1. The highest number of bacteria was 21.6×103 cell/g in Iranian biscuit while the lowest number was 14.3× 103 cell/g in local biscuit No.1 . The highest number of fungi was 16×103 colony/g and the lowest number was 5.3×103 colony/g in the Iranian and the local biscuit No.1,respectively.2. Staphylococcus aureus was the major bacteria appeared at highest level of 100% in Turkish biscuit. The lowest percentage was found in H
... Show MoreIntroduction/Aim. Roughly six percent of all malignancies diagnosed in children are malignant bone tumors. They have a dramatic effect on psychological status of children and their families. The aim of the study was to analyze the clinico-pathological features of bone tumors in Iraqi children and to assess response to treatment, outcome, and survival. Patients and methods. Over an eleven-year period, a retrospective study was done for children with bone tumors conducted on patients data that included a battery of pre-treatment investigations including a complete blood count, serum electrolyte, hepatic, and renal profile, bone marrow aspirate and biopsy, fine-needle aspiration, and imaging studies. Results. Data of 41 children with b
... Show MoreDesign system often generated relationship within the frame work of their concept of interior design a system or more can be created between design relationships within this concept in the structure of its internal space product. Through the division of all to it parts to reveal the hidden places and stages of composition and their relationship and interdependence between them. And then re- composition of all its parts, doth in the deign process at the initial stages or in the processes of treatments that are necessary after the completion of design and circulation. To be able to use other events close to the first events designed for them. In terms of idea logical in fluency and its social, economic, cultural and political dimension. As
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There is poverty because of the difference in capacity and material resources, Previously poverty known on the basis of disparity between income and inadequate income. It realize later that fare wore effects of poverty is the erosion of human capital. The human poverty is the loss of food, education, health care and shelter.
In order to provide a database that target the poor , it have been propped a document on the features of poverty and the whereabouts of the poor and the rate of disparity between provinces.
Here the goal of the research is the identify the factors affecti
... Show MoreThis study analyzes the features of historical and modern mosques in Jordan compared to that of Amman. The architecture of the Jordanian mosques reflects the images of great ancient empires and kingdoms of Europe and the Middle East. This has happened due to the geographical position of the country. From the studies of historians and archaeologists, comparative analysis of planning solutions, the use of plastics and decor of the facades of mosques, and the literature on the construction methods of the mosques allow us to conclude that age-old traditions have been preserved through the establishment of mosques in both the countries. Besides, the emergence of new features in constructing mosques has been observed. We find the influence of
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