IJE TRANSACTIONS A: Basics Vol. 32, No. 1 (January 2019) 177-183    Article in Press

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M. A. K. Benalouach, A. Sahli and S. Sahli
( Received: May 31, 2017 – Accepted in Revised Form: April 28, 2018 )

Abstract    The interaction of work fluid mechanics with that of the rotary system itself, basically composed of axes, bearings and rotors, is performed by inserting equivalent dynamic coefficients in the mathematical model of the rotor, the latter being obtained by the finite element method. In this paper, the dynamic coefficients of inertia, stiffness and damping of the flat seals analyzed here are evaluated, from the point of view of the dependence of the geometric characteristics of the seals and the operating conditions of the machine. Then, once incorporated into the entire rotating system model, the flow seals are also analyzed from the point of view of their influence on the overall dynamic response of the rotating machine. The mechanical seals of the cylindrical, conical and stepped type were analyzed, determining, for this purpose, the dynamic coefficients of damping, stiffness and inertia. In addition, the influence of physical and operational parameters of the system in relation to these elements were verified. Therefore, the modeling and analysis of flow seals are inserted in an interesting and promising way in the context of the global research theme in rotary machines.


Keywords    Fluid Seals, Finite Volume Method, Rotating Machinery, Dynamic Coefficients



تعامل مکانیک سیالات با سیستم خود چرخشی که عمدتا از محورها، یاطاقانها و روتورها تشکیل شده است، با قرار دادن ضرایب پویا معادل در مدل ریاضی روتور انجام می شود، که توسط روش المان محدود حاصل می شود. در این مقاله، ضریب پویایی اینرسی، سختی و محاسبه مهر و موم تخت در اینجا مورد ارزیابی قرار گرفته است، از دیدگاه وابستگی خصوصیات هندسی مهر و موم و شرایط عملیاتی دستگاه. سپس، هنگامی که در مدل کل سیستم چرخشی قرار می گیرد، مهر و موم جریان نیز از نظر تأثیر آنها بر پاسخ دینامیکی کلی دستگاه چرخشی تحلیل می شود. مهر و موم های مکانیکی نوع استوانه ای، مخروطی و پله ای مورد تجزیه و تحلیل قرار گرفتند و برای این منظور ضرایب پویایی مهار، سفتی و inertia تعیین شدند. علاوه بر این، تاثیر پارامترهای جسمی و عملیاتی سیستم در ارتباط با این عناصر تأیید شد. بنابراین، مدل سازی و تجزیه و تحلیل جریان مهر و موم را در یک موضوع جالب و امیدوار کننده در زمینه موضوع تحقیق جهانی در ماشین آلات دوار وارد شده است.


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