FDM SİLİNDİRİK KABUKLARIN KARMA SINIR KOŞULLARINDA DİNAMİK TEPKİSİNİN İNCELENMESİ

Bu makalede, karma sınır koşulları altındaki fonksiyonel derecelendirilmiş malzemelerden (FDM) oluşan silindirik kabukların (FDMSK’ların) dinamik tepkisi klasik kabuk teorisi (KKT) kapsamında incelenmektedir. FDM’lerin özellikleri tanımlanarak, Donnell kabuk teorisi kullanılarak temel bağıntılar ve temel denklemler türetilmektedir. Karma sınır koşulları için temel denklemlere Galerkin yöntemi uygulanarak, frekans için kapalı çözüm elde edilmektedir. Elde edilen ifade dalga sayılarına göre minimize edilerek, frekansın minimum değeri bulunmakta ve literatürdeki sonuçlarla karşılaştırılarak doğruluğu kanıtlanmaktadır. FDM'lerin serbest titreşim frekansı üzerindeki etkileri sayısal olarak detaylı bir biçimde incelenmektedir

THE INVESTIGATION OF DYNAMIC RESPONSE OF FGM CYLINDRICAL SHELLS IN MIXED BOUNDARY CONDITIONS

In this paper, the dynamic response of cylindrical shells composed of functionally graded materials (FGMs) under mixed boundary conditions is examined within the context of classical shell theory (CST). The properties of FGMs are defined and then fundamental relations and governing equations are derived using Donnell shell theory. By applying the Galerkin method to the basic equations for mixed boundary conditions, a closed-form solution for the frequency is obtained. The obtained expression is minimized according to the wave numbers, the minimum value of the frequency is found and its accuracy is proved by comparing with the results in the literature. The effects of FGMs on the free frequency of the vibration frequency are investigated in detail.

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