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.
Groundwater is very important for different uses in the present study area which represents Jisr Diyala, located in southeastern Baghdad and covered with quaternary deposits which include the shallow aquifer in the area. Groundwater and surface water were investigated to determine their suitable uses. The main ion concentrations of the wet period seemed to be lower than those in the dry period. According to TDS values, the water is classified as brackish to salty with a high degree of hardness. Most of water samples were of NaCl type due to pollution with sewage water and rock-water interaction. The results show that the water of the study area is suitable for livestock and irrigation purposes only.
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— To identify the effect of deep learning strategy on mathematics achievement and practical intelligence among secondary school students during the 2022/2023 academic year. In the research, the experimental research method with two groups (experimental and control) with a post-test were adopted. The research community is represented by the female students of the fifth scientific grade from the first Karkh Education Directorate. (61) female students were intentionally chosen, and they were divided into two groups: an experimental group (30) students who were taught according to the proposed strategy, and a control group (31) students who were taught according to the usual method. For the purpose of collecting data for the experimen
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The lithostratigraphic and biostratigraphic studies of the Shiranish Formation in the Diana area, Erbil, Northern Iraq, were conducted to distinguish the main lithostratigraphic units, depositional environment and the formation age. The Shiranish Formation in the study area can be divided into three rock units. The lower and upper units consist of marly limestone, marl and limestone deposited in the outer shelf environment, while the middle unit is dominated by laminated calcareous shale and marl deposited in the upper bathyal environment. Calcareous nannofossils showed the presence of about 20 species/genera in the studied Shiranish Formation. Three biozones are identified; Misceomarginatus pleniporus biozone;
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Praise be to God, who started his book with the praise of himself and prayers and peace be upon those who do not have a prophet after him and his family and companions and those who followed them with charity until the Day of Judgment. Either:
The research examines the meanings of the formulas of the increased verbs that were mentioned in Surat Al-Baqara, at the imam of the imams of the Islamic nation, namely, Al-Fakhri Al-Razi (d. 606 AH), may God Almighty have mercy on him. With the imams of Quranic scholars.
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