Ağır Ticari Araçlarda Kullanılan Hava Süspansiyonlu Z Tipi Yaprak Yayların Tasarımı ve Yorulma Ömrü Analizi

Öz

Otomotiv sektöründe özellikle ağır ticari araçlarda araçların ön ve arka akslarında süspansiyon elemanı olarak yaprak yaylar kullanılmaktadır. Her türlü yol koşulunda ve yük altında çalışan yaprak yaylar, tekerlekten ve yerden şasiye iletilen yüklerin sönümlenmesini sağlar. Bu sayede araçta güvenlik ve çalışma konforu sağlar. Yeni nesil araçlarda mekanik süspansiyon sistemleri yerini havalı süspansiyon sistemlerine bırakmıştır. Havalı süspansiyon sistemlerinde; Özellikle ağır ticari araçlarda kullanılan Z tipi parabolik yaprak yaylar, hava körükleri ile geri esneme sağlayan yaprak yay türüdür. Bu çalışmada, Z tipi parabolik yaprak yay tasarımı ve bu yayın sonlu elemanlar analiz yöntemi ile hazırlanan model üzerinden form ve gerilme analizleri yapılmıştır. Sonlu elemanlar analizi kullanılarak bu yaprak yayın yüksek gerilim bölgeleri belirlenmiş ve uygun tasarım seçilmiştir. Son olarak N-Code programında ve fiziksel testler ile bu yaprak yaya ait yorulma ömrü elde edilmiştir.

Anahtar Kelimeler

• Z tipi yaprak yay
• Parabolik yaprak yay
• süspansiyon sistemleri
• sonlu elemanlar

Design and Fatigue Life Analysis of Air Suspension Z Type Leaf Springs Used in Heavy Commercial Vehicle

Öz

Leaf springs are used as suspension elements in the front and rear axles of vehicles in the automotive industry, especially in heavy commercial vehicles. Leaf springs working all road conditions and under load, it provides damping of the loads transmitted from the wheel and from the ground to the chassis. In this way, it ensures the safety and working comfort in the vehicle. Mechanical suspension systems have been replaced by air suspension systems in new generation vehicles. In air suspension systems; Z type parabolic leaf springs, especially used in heavy commercial vehicles, is a type of leaf spring that provides spring back with air bellows. In this study; Z type parabolic leaf spring design and finite element model of this leaf spring were prepared and form and stress analyzes were performed on the model. By using finite element analysis, high-tension regions of this leaf spring were determined and the appropriate design was selected. Finally, the fatigue life of this spring was obtained in the N-Code program and physical test.

Anahtar Kelimeler

• Z type leaf springs
• Parabolic leaf springs
• Suspension systems
• Finite elements

Kaynakça

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