IJE TRANSACTIONS B: Applications Vol. 24, No. 2 (July 2011) 155-164   

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M. Akhondizadeh. Korrani*

Mechanical Engineering Department of Shahid Bahonar University of Kerman, Kerman-Iran



M. Fooladi. Mahani

Mechanical Engineering Department of Shahid Bahonar University of Kerman, Kerman-Iran




*Corresponding Author

( Received: July 26, 2010 – Accepted in Revised Form: April 23, 2011 )

Abstract    In this paper, the dynamic response of a three-rotor flexible coupling to the angularmisalignment has been studied. The coupling is a power transmission agent between the motor andgearbox, in the power transmission system of SAG Mill (semi autogenously mill) in the Gol-e-Gohariron ore complex in Sirjan, Iran. Degrees of freedom of the system are the model's lateral deflectionsand the rigid-body linear motions. The equations of motion are obtained by using the Lagrangeequations through successive partial differentiation of the kinetic and potential energies. In thedynamic model, the middle rotor is considered as an eccentric flexible Jeffcott rotor. The gearboxinput shaft is considered to be angularly misaligned with respect to the motor shaft. Diagrams of theamplitudes versus the frequency ratio reveal the system dynamic response to the angularmisalignment.


Keywords    Rotor dynamic, Flexible coupling, Misalignment, Vibration


چکیده    در کار حاضر، پاسخ ديناميکي يک کوپلينگ انعطافپذير شامل سه روتور با ناهمراستايي زاويهاي موردبررسي قرار گرفته است. اين کوپلينگ، واسط انتقال قدرت بين موتور و گيربکس در سيستم انتقال قدرت آسياينيمه خودشکن معدن سنگ آهن گل گهر سيرجان در ايران است. درجات آزادي سيستم، انعطاف جانبي در سيستم وحرکات خطي جسم صلب هستند. معادلات حرکت سيستم با روش ديناميک لاگرانژي و با مشتق گيري پياپي ازانرژيهاي جنبشي و پتانسيل استخراج ميشوند. در مدل ديناميکي، روتور مياني، يک روتور انعطافپذير مدلجفکات داراي خروج از مرکز، در نظر گرفته شده است. ناهمراستايي زاويهاي براي محور ورودي گيربکس نسبتبه محور خروجي موتور درنظر گرفته ميشود. نمودارهاي دامنه بر حسب فرکانس نسبي، پاسخ سيستم به ناهم-راستايي زاويهاي را آشکار ميسازد.


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