Hasan ÖZTÜRK, Çınar Emine YENİ, Aysun BALTACI, Rafet Can ÜMÜTLÜ, Özgür SAYER

Çatlaklı Kompozit Plakaların Dinamik Kararlılığı

Bu çalışmada, sonlu elemanlar yöntemi kullanılarak periyodik eksenel yüklemeye maruz kalan çatlaklı kompozit plakaların dinamik kararsızlık bölgesi sayısal olarak incelenmiştir. Klasik laminasyon teorisine dayanan kompozit plaka, sonlu elemanlar yöntemi kullanılarak modellenmiştir. Kompozit plakanın sınır şartlarının bir taraftan sabitlendiği, diğer tarafların serbest olduğu varsayılmaktadır. Kompozit plaka, her biri dört düğüme sahip kare plaka elemanlarına bölünmüştür. Her düğümün bir vektörel ve iki dönme serbestlik derecesine sahiptir, bu yüzden bu kare plaka elemanlar on iki serbestlik derecesine sahiptir. Plakanın dinamik kararsızlık bölgesi hesaplamak için kullanılan Mathieu-Hill tipi hareket denklemi, Lagrange denkleminden elde edilen enerji ifadeleri kullanılarak oluşturulmuştur. Geliştirilen MATLAB sonlu elemanlar kodu kullanılarak çatlağın kompozit plakalar için dinamik kararsızlık bölgesi üzerindeki etkisi incelenmiştir.

Dynamic Stability of Cracked Composite Plates

In this study, the dynamic instability region of cracked composite plates subjected to periodic axial loading has been investigated numerically by using the finite element method. A composite plate based on classical lamination theory is modeled by using the finite element method. It is assumed that the boundary condition of the composite plate is fixed on one side and the other sides are free. The composite plate is divided into square plate elements, each having four nodes. Each node has one translational and two rotational degrees of freedom, therefore, the square plates have twelve degrees of freedom. Mathieu-Hill type motion equation, which is used to calculate the dynamic instability region of the plate is created by using energy expressions obtained from the Lagrange equation. The developed MATLAB finite element code is used to examine the effect of crack on dynamic instability region for composite plates.

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