IJE TRANSACTIONS A: Basics Vol. 32, No. 1 (January 2019) 171-176    Article in Press

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M. Akhondizadeh, G. Yousefi and M. Fooladi Mahani
( Received: August 04, 2018 – Accepted in Revised Form: January 03, 2019 )

Abstract    Deformation of the silo wall due to the single ball impact is modeled in ANSYS. The material in silo, as a Winkler bed, is replaced by spring-damper elements and the spring stiffness and damper coefficients are evaluated of the granular material and wall properties. The granular material deformation under the specified force is measured to evaluate the granular stiffness to be used for determining the appropriate spring stiffness in ANSYS model. Geometrical parameters and boundary conditions are set according to the properties of a laboratory silo containing magnetite concentrate. Effects of impact parameters including the ball size and the impact position on the hopper displacement are taken into account. Comparison of simulation results with experimental data confirms that the wall displacement is an indicator of the ability of impact to solve obstruction. Simulation will be an alternative to expensive and time consuming experimental procedures for specifying the optimal impacts for obstruction solution.


Keywords    Hopper Displacement, Winkler Bed, Simulation, Silo, ANSYS



تغییر شکل بدنه سیلو در اثر برخورد گلوله در نرم افزار انسیس مدل می¬شود. مواد دانه¬ای درون سیلو بعنوان یک بستر وینکلر در نظر گرفته شده و با فنر و دمپر جایگزین می¬شود و ضرایب آنها بر حسب خواص مواد و خواص فیزیکی بدنه سیلو تعیین می¬شود. با یک وزنه مشخص که بر روی مواد قرار داده شده و میزان جابجایی تحت آن اندازه گیری می¬شود، ضریب الاستیک مواد برای استفاده در نرم افزار تعیین می¬شود. پارامترهای هندسی و شرایط مرزی برای سیلویی که حاوی ذرات مکنتیت است مشخص می¬گردد. اثر پارامترهای ضربه شامل اندازه گلوله و محل برخورد بر جابجایی بدنه سیلو بررسی می¬گردد. مقایسه نتایج مدلسازی مربوط به تغییر شکل بدنه سیلو و نتایج آزمایشگاهی مربوط به قدرت رفع انسداد ضربات نشان می¬دهد که جابجایی بدنه یک پارامتر تاثیرگذار در رفع انسداد سیلو است. مدلسازی نرم افزاری می¬تواند بعنوان جایگزین روش پرهزینه و زمان بر آزمایشگاهیجهت تعیین برخوردهای بهینه برای رفع انسداد سیلو استفاده گردد.


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