Vibration Analysis of a Cantilever Composite Beam by Equivalent Mass-Spring-Damper Systems

Öz

Composite materials are widely used in industrial structures such as manipulators because they are lightweight and durable. In this work, the vibration analysis of a cantilever composite beam with [0/90] lay-up was studied. An end point mass was added to the structure. An initial displacement was applied to the end point and the free vibration was analyzed experimentally first. Exponential decay was found. Natural frequencies were determined by taking the Fast Fourier Transform of the vibration signal. The system was analyzed in ANSYS and simulation results were obtained. The damping coefficient was determined by trial using the experimental exponential decay. An equivalent mass-spring-damper model (MSD) was established using static deflection, natural frequency and exponential decay obtained experimentally or by simulation. MSD-analytical results were obtained by the Laplace transform method. The experimental, simulation, and analytical results were compared for different end point initial displacement values. It was observed that the results are in good agreement.

Anahtar Kelimeler

• Composite beam,Vibration analysis,Equivalent system,ANSYS

Eşdeğer Kütle-Yay-Sönüm Elemanı Kullanılan Ankastre Kompozit Bir Kirişin Titreşim Analizi

Öz

Kompozit malzemeler hafif ve dayanıklı oldukları için manipülatör olarak endüstriyel yapılarda yaygın olarak kullanılmaktadır. Bu çalışmada, [0/90] oryantasyona sahip ankastre kompozit bir kirişin titreşim analizi çalışılmıştır. Yapının ucuna kütle eklenmiştir. Başlangıç koşulu olarak deplasman uç noktaya uygulanmış ve deneysel sistemin serbest titreşimi elde edilmiştir. Eksponansiyel sönüm bulunmuştur. Titreşim sinyalinin Hızlı Fourier dönüşümü kullanılarak doğal frekanslar hesaplanmıştır. Sistem ANSYS programında analiz edilmiş ve simülasyon sonuçları elde edilmiştir. Sönüm katsayısı, deneyden elde edilen eksponansiyel sönümden yararlanılarak hesaplanmıştır. Deneysel ya da simülasyondan elde edilen statik çökme, doğal frekans ve eksponansiyel sönüm kullanılarak sistemin eşdeğer kütle-yay-sönüm elemanı oluşturulmuştur. Eşdeğer kütle-yay-sönüm elemanı sonuçları Laplace dönüşüm metodu ile elde edilmiştir. Deneysel, simülasyon ve analitik sonuçlar uç noktanın farklı başlangıç yer değiştirme değerleri için karşılaştırılmıştır. Sonuçların uyumluluğu gözlemlenmiştir.

Anahtar Kelimeler

• Kompozit kiriş,Titreşim analizi,Eşdeğer sistem,ANSYS

Kaynakça

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