نویسندگان
دانشکده مهندسی مکانیک، دانشگاه تبریز، تبریز
چکیده
اتوبالانسر دینامیکی ساچمه‌ای علاوه‌بر مزیت‌های مختلف، دارای دو عیب اساسی یعنی محدود بودن ناحیه بالانس پایدار و افزایش دامنه روتور در ناحیه گذرا است که سبب محدودیت استفاده از این نوع اتوبالانسر می‌شود. به‌همین منظور به‌تازگی مدل جدیدی از این اتوبالانسر با نام اتوبالانسر ساچمه- فنر ارائه شده است که تا حد قابل ملاحظه‌ای عیب‌های مذکور را رفع کرده است. با توجه به مزیت اتوبالانسر جدید و برای کاربردی کردن آن لازم است رفتار دینامیکی آن به‌طور دقیق بررسی شود. در مطالعات پیشین رفتار دینامیکی روتور با یاتاقان‌های خطی و مجهز به اتوبالانسر ساچمه- فنر بررسی شده است ولی در عمل ممکن است یاتاقان‌ها دارای رفتار غیرخطی باشند. لذا در مقاله حاضر به‌منظور بررسی دقیق‌تر، برای اولین بار رفتار دینامیکی اتوبالانسر ساچمه- فنر برای بالانس روتور با یاتاقان‌های غیرخطی با روش مقیاس‌های چندگانه مطالعه شده است. نتایج نشان می‌دهد که یاتاقان‌های غیرخطی خللی در مزیت‌های اتوبالانسر ساچمه- فنر ایجاد نمی‌کند.
کلیدواژه‌ها
عنوان مقاله [English]
Investigating the Dynamics of a Ball-Spring Autobalancer in a Rotor with Non-Linear Bearings
نویسندگان [English]
- M. Rezaee
- M. M. Ettefagh
- R. Fathi
چکیده [English]
Although the traditional automatic ball balancer (ABB) has numerous advantages, it has two major deficiencies, i.e., it has a limited balance stable region and it increases the vibration amplitude of the rotor at transient state. These deficiencies limit the applicability of ABBs. In this regard, a new type of ABB called “the Ball-spring autobalancer” has been proposed to resolve the mentioned deficiencies of the traditional ABBs. In order to investigate the capability of the Ball-spring AB in balancing rotors, it is necessary to study its dynamics accurately. The dynamics of a rotor with linear bearing equipped with a Ball-spring AB has been studied previously; however, in real situations, the bearings have nonlinear characteristics. Here, the dynamics of a rotor with nonlinear bearings equipped with a Ball-spring AB is investigated by the multiple scales method for the first time. The results show that the nonlinearity at the rotor bearings does not impair the advantages of the Ball-spring AB.
کلیدواژه‌ها [English]
- Automatic ball-spring balancer
- Nonlinear bearings
- Multiple scale method
- Dynamic behavior
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