Investigation of the Effects of Polyurethane Foam Reinforcement Thickness on Modal Properties of Sandwich Beams

Abstract

In this study, the effects of polyurethane foam (PUF) reinforcement thickness on modal properties (natural frequency, mode shape and damping ratio) of sandwich beams were investigated. For this purpose, two types of PUF reinforced beams were used. The one of these was reinforced onto one surface of aluminum metal face sheet and the other was reinforced between two aluminum metal face sheets were produced. Each type was prepared in different PUF thicknesses from 10 mm to 50 mm. The modal properties were obtained by using experimental modal analysis (EMA) method for both types.

Keywords

• Modal analysis,Polyurethane Foam,Sandwich Beam

Poliüretan Köpük Takviye Kalınlığının Sandviç Kirişlerin Modal Özellikleri Üzerine Etkilerinin İncelenmesi

Abstract

Bu çalışmada, poliüretan köpük (PUF) takviye kalınlığının sandviç kirişlerin modal özelliklerine (doğal frekans, mod şekli ve sönüm) etkileri araştırılmıştır. Bu amaçla, iki tip PUF takviyeli kiriş, biri alüminyum meta tabakasının bir yüzeyi üzerine ve diğeri iki alüminyum metal tabaka arasına takviye edilmiştir. Her tip 10 mm'den 50 mm'ye kadar farklı PUF kalınlıklarında hazırlanmıştır. Modal özellikler, her iki tip için deneysel modal analiz (EMA) yöntemi kullanılarak elde edilmiştir

Keywords

• Doğal Frekans,Poliüretan Köpük,Sandviç Kiriş

References

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