Mekanik Bir Sistemin Bir Ters Rezonans Frekansının Kütle Eklenerek Değiştirilmesi

Yıl 2018, Cilt: 30 Sayı: 2, 127 - 134, 19.09.2018

Orhan Çakar

Öz

Ters rezonans frekansı mekanik sistemlerin dinamik
özelliklerinden biridir ve frekans tepki fonksiyonu grafiklerinde ters tepeler
olarak gözükürler. Bir yapı belirli bir noktadan ters rezonans frekansındaki
harmonik bir kuvvet ile tahrik edildiğinde yapının belirli noktaları titreşim
hareketi yapmayabilir. Bu bakımdan bazı titreşim problemlerinin çözümünde bu
özellikten faydalanılmaktadır. Bu çalışmada mevcut bir sistemin noktasal veya
çapraz frekans tepki fonksiyonlarında belirli bir ters rezonansı kütle eklemek
suretiyle başka bir frekansa kaydırma üzerine bir yöntem sunulmuştur. Yöntem
matematikten bilinen Sherman-Morrison formülüne dayalı olup orijinal sistemin
frekans tepki fonksiyonlarını kullanmaktadır. Bu yöntem sistemin fiziksel
özelliklerinin veya modal özelliklerinin bilinmesine gerek duymadığından
oldukça avantajlıdır. Yöntemin geçerliliği ve etkinliği altı serbestlik
dereceli bir sistem üzerinde gerçekleştirilen çeşitli sayısal uygulamalarla
gösterilmiştir. 

Anahtar Kelimeler

Titreşim, Ters rezonans, Doğal frekans, Yapısal değişiklik, Frekans Tepki Fonksiyonu, Sherman-Morrison formülü

Kaynakça

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