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.
WA Shukur, FA Abdullatif, Ibn Al-Haitham Journal For Pure and Applied Sciences, 2011 With wide spread of internet, and increase the price of information, steganography become very important to communication. Over many years used different types of digital cover to hide information as a cover channel, image from important digital cover used in steganography because widely use in internet without suspicious.
تم تقييم المعرفة والوعي تجاه داء الكريبتوسبوريديوس في هذه الدراسة خلال الفترة من أبريل 2009 حتى يونيو 2011 ، من بين 188 شخصًا من كلا الجنسين تم تقسيمهم إلى مجموعات ومجموعات فرعية مختلفة على النحو التالي المجموعة 1: تشمل 48 طبيبًا من مختلف المستشفيات والرعاية الصحية الأولية مراكز في بغداد تم تقسيم هذه المجموعة إلى 30 طبيبًا متخصصًا و 18 طبيبًا ممارسًا عامًا. المجموعة الثانية: تضم 45 عضو هيئة تدريس من قسم الأحياء ، قس
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Drug misuse is defined as using of drugs for a non-therapeutic or non-medical purpose. In Iraq drug misuse is a major problem because almost any drug can be easily obtained from pharmacies. Appetite- stimulant drugs are example of drugs that are widely used without a prescription. The study included 230 patients who use these drugs in Babylon. A questionnaire included the following questions ; age, sex, marital state, the reason for use the drug , whether the drug is prescribed by physician or not , type of drug used , the frequency of daily dose and lastly the extent of side effects of the drugs used. The results showed that the age range of 35% of subjects were (17-21) years old and 70% of participants were females. The study also show
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Provisions of combat games In Islamic Jurisprudence
The training of great importance in the play, in building optic and intellectual broadcast codes tags, and then comes after the recipient at the reception of such codes and decoded tags, and is the rhythm, the color of the most important elements of configuration, consistent with other elements, Kaltmathl, and focus, and harmony, and dissonance
This study detects the presence of cholesterol in an Iraqi plant named Suaeda baccata Forsk of the family Chenopodiacae, wildly and widely grown in Iraq. The absence of any publication concerning the sterol content of this Suaeda specie, and the industrial importance of cholesterol depending on its role as a precursor in the synthesis of some hormones, like progesterone, acquired this study its value. The investigations revealed the presence of cholesterol that was proved by TLC together with the standard compound cholesterol, and anisaldehyde spray reagent using three different solvent systems, then authenticated by HPLC, in which the reten
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This investigation is a study of the length of time where drops can exist at an oil-water interface before coalescence take place with a bulk of the same phase as the drops. Many factors affecting the time of coalescence were studied in is investigation which included: dispersed phase flow rate, continuous phase height, hole size in distributor, density difference between phases, and viscosity ratio of oil/water systems, employing three liquid/liquid systems; kerosene/water, gasoil/water, and hexane/water. Higher value of coalescence time was 8.26 s at 0.7ml/ s flow rate, 30cm height and 7mm diameter of hole for gas oil/water system, and lower value was 0.5s at 0.3ml/s flow rate, 10 cm height and 3mm diameter of hole for hexane
... Show MoreSystematic Reviews in Pharmacy is a monthly Peer-review open access Journal,different scientists involved in Pharmaceutical research and development
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