Faruk Fırat ÇALIM, Murat BİNGÖL, BEYTULLAH TEMEL

Değişken kesitli kompozit çubukların serbest titreşim analizi

Değisken kesitli kompozit çubukların serbest titresimleri teorik olarak incelenmistir. Değisken kesitli doğru eksenli kompozit çubukları idare eden denklemler Timoshenko çubuk teorisi kullanarak elde edilmistir. Formülasyonda eksenel ve kayma deformasyonu etkileri göz önüne alınmıstır. Çubuk malzemesi homojen, lineer elastik ve anizotropik kabul edilmistir. Laplace uzayında elde edilen skaler formdaki adi diferansiyel denklemler, problemin dinamik rijitlik matrisini kesin olarak hesaplamak için tamamlayıcı fonksiyonlar yöntemi yardımıyla sayısal olarak çözülmektedir. Değisken kesitli doğru eksenli kompozit çubukların serbest titresim analizi yapılmıstır. Kesit değisim parametresi, sınır sartları ve E1/E2 oranının serbest titresime etkisi arastırılmıstır. Bu çalısmada elde edilen sonuçların ANSYS sonuçları ile uyum içinde olduğu görülmüstür.

Free vibration analysis of composite rods with variable cross-section

The free vibration of composite beams with variable cross-section is theoretically investigated. The governing equations for composite straight beams with variable cross-section are obtained using Timoshenko beam theory. The effect of axial and shear deformations are considered in the formulations. The material of the rod is assumed to be homogeneous, linear elastic and anisotropic. Ordinary differential equations in scalar form obtained in the Laplace domain are solved numerically using the complementary functions method to calculate the dynamic stiffness matrix of the problem accurately. The free vibration of composite straight rods with variable crosssection are analyzed. The effects of cross-section variability parameter, boundary conditions and E1/E2 ratio on free vibration is investigated. The results obtained in this study are found to be in good agreement with those obtained from ANSYS.

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