Düz ve Bükümlü Plakaların Büküm Açısına Bağlı Modal Analizi

Öz

İzotropik ince plakaların dinamik özelliklerinden biri olan doğal frekans üzerinde bükümlü açı ve sınır koşulu farklılıklarının etkisi araştırılmıştır. Düz ve bükümlü yapıların modal analizleri tek ve çift tarafı sabit sınır koşulları altında ANSYS ile yapılmıştır. Yapıların serbest titreşim sonuçlarının validasyonu Solidworks ile yapılmıştır. Her yapının ilk beş doğal frekansı elde edilmiş ve boyutsuz doğal frekans parametreleri cinsinden değerler tablo ve grafiklerle yorumlanmıştır. Tek tarafı sabit sınır koşulu için ilk beş doğal frekansta büküm açısındaki artışa bağlı olarak hem bir artış hem de bir azalma gözlemlenebilirken, çift taraflı sabit durumda büküm açısındaki artışın doğal frekanslar üzerindeki etkisi yüksek katlanmış açı değerlerinde çok daha azdır. Büküm açısı - boyutsuz doğal frekans grafiklerindeki ani değişimlerin sebebinin mode şekli değişimi olduğu görülmektedir.

Anahtar Kelimeler

• Büküm açısı
• Serbest titreşim analizi
• Sonlu elemanlar yöntemi
• İnce plaka
• Modal analiz

FOLDED ANGLE DEPENDENT MODAL ANALYSIS OF THE FLAT AND FOLDED PLATES

Öz

The effect of folded angle and boundary condition differences on the natural frequency, which is one of the dynamic characteristics of isotropic thin plates, is investigated. Modal analyzes of flat and folded structures are performed with ANSYS under cantilever and two-side-fixed boundary conditions. The validation of the free vibration results of the structures is performed with Solidworks. The first five natural frequencies of each structure are obtained, and the values in terms of non-dimensional natural frequency parameters are interpreted with the tables and graphics. While both an increase and a decrease can be observed depending on the increase in the folded angle in the first five natural frequencies for the cantilever boundary condition, the effect of the increase in the folded angle on the natural frequencies in the two-sided-fixed structures is much less in the higher folded angle values. It is seen that the reason for the sudden changes in the folded angle - non-dimensional natural frequency graphs is the mode shape change.

Anahtar Kelimeler

• Folded angle
• Free vibration analysis
• Finite element method
• Thin plate
• Modal analysis

Kaynakça

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