Development of Sound Insulation Material Using Flexible Epoxy with Elastic Properties and Recycled Polyurethane Foams

Öz

Improving acoustic ergonomics in electric vehicles increases sensitivity to environmental noise, leading to research beyond traditional sound insulation materials towards new alternatives. In this study, recycled polyurethane (PU) foam material was used to attenuate sound waves and reduce their wavelength. To prevent the transmission of sound waves through the foam material into other environments, flexible epoxy with elastic properties, ST37 steel, and Ethylene Propylene Diene Monomer (EPDM) sound barriers were developed. Sound absorption coefficients (SAC) and sound transmission losses (STL) were determined based on the thickness of the foam material used and the barrier materials. The tests were conducted using an impedance tube. The findings showed that the developed flexible epoxy sound barrier provided a more effective sound transmission loss. It was observed that increasing the thickness of the PU foam material alone did not provide sufficient sound insulation, but when used with flexible materials like EPDM or flexible epoxy barrier, superior sound insulation was achieved. Considering that the developed insulation materials also possess dielectric properties, it is recommended that these materials be evaluated as alternatives for both sound and electrical insulation.

Anahtar Kelimeler

• Sound Absorption Coefficient
• Sound Transmission Loss
• Sound Insulation
• Flexible Epoxy
• Polyurethane Foam

ELEKTRİKLİ ARAÇLAR İÇİN ESNEK EPOKSİ VE GERİ DÖNÜŞTÜRÜLMÜŞ POLİÜRETAN KÖPÜK TABANLI SES YALITIMI

Öz

Elektrikli araçlarda ses ergonomisinin iyileştirilmesi, çevresel gürültülere karşı duyarlılığı artırdığı için, geleneksel ses izolasyon malzemelerinin ötesine geçilerek yeni malzemeler üzerine araştırmalar yapılmaktadır. Bu çalışmada, ses dalgalarını zayıflatarak dalga boyunu küçültmek amacıyla geri dönüştürülmüş poliüretan (PU) köpük malzeme kullanılmıştır. Ses dalgalarının köpük malzemeden diğer ortama geçişini engellemek için elastik özelliklere sahip esnek epoksi, ST37 çelik ve Etilen Propilen Dien Metilen (EPDM) ses bariyerleri geliştirilmiştir. Kullanılan köpük malzemenin kalınlığı ve bariyer malzemelerine bağlı olarak ses yutum katsayıları (SAC) ve ses iletim kayıpları (STL) belirlenmiştir. Testler, empedans tüpü kullanılarak gerçekleştirilmiştir. Elde edilen bulgular, geliştirilen esnek epoksi ses bariyerinin ses iletim kaybını daha etkin bir şekilde sağladığını göstermiştir. PU köpük malzemenin kalınlığı artırılsa bile tek başına yeterli ses yalıtımı sağlamadığı, ancak esnek özelliklere sahip EPDM veya esnek epoksi bariyer malzeme ile kullanıldığında üstün ses yalıtımı sağladığı tespit edilmiştir. Geliştirilen izolasyon malzemelerinin dielektrik özelliklere de sahip olması nedeniyle, bu malzemelerin hem ses hem de elektrik yalıtımı için alternatif malzemeler arasında değerlendirilmesi önerilmektedir.

Anahtar Kelimeler

• Ses Yutum Katsayısı
• Ses İletim Kaybı
• Ses İzolasyonu
• Esnek Epoksi
• Poliüretan Köpük

Kaynakça

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