Manyetik sıvılı damperlerin yapısal analizi

Bu çalışmada kamyon, kamyonet ve traktör gibi ticari araçlara uygulanabilen manyeto Reolojik (MR) damperler üzerinde durulmuş ve mekanik davranışları araştırılmıştır. Yarı-aktif titreşim kontrol sistemleri, fazla bir güç gereksinimleri olmadan hem aktif hem de pasif kontrol sistemlerinin (avantajlarını) özelliklerini taşımalarından ötürü son 10 yıl içerisinde önemli bir ilgi odağı haline gelmiştir. MR damperlerde, damper sıvısının uygun bir manyetik alan ile aktifleştirilmesi, bu sıvıların görünür dinamik viskozitelerinde çok hızlı ve büyük artışlara neden olmaktadır. Bu tür sıvılar, bulundukları durumdan manyetik alan etkisiyle neredeyse yarı-katı durumuna sadece birkaç milisaniyede geçebilmektedirler ve manyetik alanın kaldırılmasıyla süreç ters yönde aynı hızda gerçekleşmektedir. Yüksek bir çalışma güvenirliğine sahip bu damperler, herhangi bir nedenden ötürü aktifleşmeyi sağlayan elektrik akımının kesilmesi halinde, klasik bir damper gibi çalışmaktadırlar. Bu araştırmada, değişik çalışma koşulları altında damperde oluşan gerilmeler ve bunların damper üzerindeki etkileri sonlu elemanlar analizi ile incelenmiştir.

In the present study,it has been focused on the magnetorheological (MR) dampers that can be used in vehicles such as truck, pickup truck, and tractor, and their mechanical behaviors have been investigated. Semi-active vibration control systems have attracted much interest last decade since they can be used in both active and semi-active vibration control without consuming much power. In the MR dampers, damper fluids change their apparent viscosity within a few millisecond, which make them almost a semi-solid material, when they are subjected to a certain magnetic field. If the magnetic field is removed, the phenomena is reversed with the same speed.These dampers have a high operating safety such that when the supplied power went out, the damper can operate as the conventional passive dampers. In this paper, the stresses that developed under various operation conditions and their effects on the damper's mechanical behavior have been analyzed using finite element method (FEM).

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