Topology Optimization and Structural Design of a Fowler Flap Bracket for Additive Manufacturing Under Analytical Aerodynamic Loads

Öz

Reducing structural weight in commercial aviation is a primary challenge for efficiency. This study introduces a design framework optimizing a Fowler flap bracket using topology optimization (TO) tailored for additive manufacturing (AM) constraints. Rather than expensive fluid simulations, the methodology utilizes analytical loads from Boeing 737 coefficients. Baseline analysis exposed an excessive safety factor of 15.8, highlighting mass reduction potential. Consequently, a SIMP optimization was executed under a 50% volume reduction target, embedding Laser Powder Bed Fusion (L-PBF) constraints. The reconstructed NURBS geometry achieved 49% mass reduction (1.65 kg to 0.85 kg) while preserving rigidity with 0.16 mm deformation. Static verification confirmed a safety factor of 10.72. Crucially, high-cycle fatigue analysis incorporating surface roughness penalties substantiated infinite life (10^8 cycles) and a minimum safety factor of 1.22. This validates the methodology's effectiveness in lightweighting critical aerospace components without compromising airworthiness.

Anahtar Kelimeler

• Structural analysis
• aerospace parts
• topology optimization
• additive manufacturing

Teşekkür

I would like to express my gratitude to Dr. Okan Bakbak for his contributions during the compilation phase of this project.

Analitik Aerodinamik Yükler Altında Eklemeli İmalata Uygun Fowler Flap Braketinin Topoloji Optimizasyonu ve Yapısal Tasarımı

Öz

Ticari havacılıkta yapısal ağırlığın azaltılması verimlilik için temel bir zorluktur. Bu çalışma, eklemeli imalat kısıtlamalarına uygun Topoloji Optimizasyonu (TO) kullanarak bir Fowler flap braketini optimize etmektedir. Metodoloji, pahalı akışkan simülasyonları yerine Boeing 737 katsayılarından türetilen analitik yükleri kullanır. Temel analiz, 15.8'lik aşırı bir güvenlik katsayısı ortaya koyarak kütle azaltım potansiyelini vurgulamıştır. Sonuç olarak, Lazer Toz Yatak Füzyonu (L-TFY) kısıtları gömülerek %50 hacim azaltma hedefiyle SIMP optimizasyonu gerçekleştirilmiştir. Elde edilen NURBS geometrisi, rijitliği korurken kütleyi %49 oranında (1.65 kg'dan 0.85 kg'a) düşürmüştür. Statik doğrulama 10.72'lik bir güvenlik katsayısı teyit etmiştir. Önemli olarak, yüzey pürüzlülüğü cezalarını içeren yüksek döngülü yorulma analizi, sonsuz ömür (10^8 çevrim) ve minimum 1.22 güvenlik katsayısı ile yapıyı doğrulamıştır. Bu sonuç, metodolojinin kritik havacılık bileşenlerini güvenlikten ödün vermeden hafifletmedeki etkinliğini kanıtlamaktadır.

Anahtar Kelimeler

• Yapısal Analiz
• Havacılık Yapıları
• Topoloji Optimizasyonu
• Eklemeli İmalat

Teşekkür

Projenin derlenmesi aşamasındaki katkılarından dolayı Dr. Okan Bakbak'a teşekkürlerimi sunarım.

Kaynakça

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