The air flow pattern in a co-current pilot plant spray dryer fitted with a rotary disk atomizer was determined experimentally and modelled numerically using Computational Fluid Dynamics (CFD) (ANSYS Fluent ) software. The CFD simulation used a three dimensions system, Reynolds-Average Navier-Stokes equations (RANS), closed via the RNG k −ε turbulence model. Measurements were carried out at a rotation of the atomizer (3000 rpm) and when there is no rotation using a drying air at 25 oC and air velocity at the inlet of 5 m/s without swirl. The air flow pattern was predicted experimentally using cotton tufts and digital anemometer. The CFD simulation predicted a downward central flowing air core surrounded by a slow recirculation zones near the walls for both conditions. Analysis of CFD simulation revealed that rotation of atomizer resulted in a swirling motion of the central air core. Simulations results were in good agreement with experimental data.
يهدف البحث إلى تشخيص أوجه القصور ونقاط الضعف في تطبيق أبعاد جودة الحياة الوظيفية ومدى تأثيرها على اتجاهات وسلوكيات الموظفين، وبالتالي علاقتها بتعزيز مقدراتهم الجوهرية. وتنبع القيمة العلمية للبحث من إبراز أهمية أبعاد جودة حياة العمل في تحسين الكفاءة الإنتاجية للعاملين في القطاع العام ورفع مستوى الأداء التنظيمي. ولأن جودة الحياة العملية تلعب دوراً مهماً في تعزيز المقدرات الأساسية للموظفين في القطاع الع
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Composite materials are widely used in the engineered assets as aerospace structures, marine and air navigation owing to their high strength/weight ratios. Detection and identification of damage in the composite structures are considered as an important part of monitoring and repairing of structural systems during the service to avoid instantaneous failure. Effective cost and reliability are essential during the process of detecting. The Lamb wave method is an effective and sensitive technique to tiny damage and can be applied for structural health monitoring using low energy sensors; it can provide good information about the condition of the structure during its operation by analyzing the propagation of the wave in the
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The aim of this study was to evaluate the effects of local application of bisphosphonate gel and recombinant human bone morphogenic protein 2 gel, on titanium dental implant stability and marginal bone level. Twenty-seven patients with upper and lower missing posterior tooth/teeth were included in the study with a total of 71 implants that were used for rehabilitation. The implants were randomly divided into 4 groups: 3 study groups and 1 control. Group1; local application of bisphosphonate gel, group 2; local application of recombinant human bone morphogenic protein 2 gel, group 3; local application of a mixed formula of both gels. The gel application was immediately preimplant insertion, group 4; implant insertion without application of a
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The effect of time (or corrosion products formation) on corrosion rates of carbon steel pipe in aerated 0.1N NaCl
solution under turbulent flow conditions is investigated. Tests are conducted using electrochemical polarization
technique by determining the limiting current density of oxygen reduction in Reynolds number range of 15000 to 110000
and temperature range of 30 to 60oC. The effect of corrosion products formation on the friction factor is studied and
discussed. Corrosion process is analyzed as a mass transfer operation and the mass transfer theory is employed to
express the corrosion rate. The results are compared with many proposed models particularly those based on the
concept of analogy among momentum, heat,
Games engagement has become one of the main concerns in game industry. Early study revealed that Malaysian digital traditional games are suffering with the same issue due to several factors. One of it is the lack of the game itself. Although many Malaysian traditional games have been digitized, none of them has incorporated rewards despite its importance in games engagement. Realizing the importance of rewards in games engagement, one of Malaysian traditional Congkak has been chosen to be enhanced by incorporating rewards. Experiments have been conducted among 50 gamers among the Millennials. Prior interview, game demo and human test are conducted. Experiments focused on the influence of rewards on games flow, games challenge, and its ef
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The political struggle being waged by Muslims today is one of the most important issues that have preoccupied the Arab and international media, and the failures that have afflicted Muslims in our contemporary world have negatively affected the younger generations and led them, and with the influence of anti-Islam media, to rely on accusing Islam as a religion with all the negative in Islamic and Arab society . So secularism took its role in spreading these concepts by deviating from its course from the concept of science to the concept of (the religion).
From here the calls for reform rose to return the Muslims to the incubator of Islam, so people turned around them, but they turned into competing Islamic polit