Otomobil debriyajları için elastomerik damperin modellenmesi, analizleri ve doğrulanması
Date
2019-06-12
Authors
Journal Title
Journal ISSN
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Publisher
Bursa Uludağ Üniversitesi
Abstract
Otomobillerde artan yüksek konfor gereksinimleri, optimum sistem tasarımı ve uzun kullanım ömrü gerekliliklerini ortaya koymuştur. Bu tez çalışmasında otomobil debriyaj sistemlerinde elastomer tabanlı malzemelerin sönümleyici olarak kullanılması tasarım, test ile doğrulama, tasarım ve sistem optimizasyonu temel aşamaları dikkate alınarak incelenmiştir. Yapılan çalışmalarda geleneksel metal helisel yaylar ile karşılaştırma yapılarak, elastomer yaylı ve metal yaylı sistemlere ait avantaj ve dezavantajları analiz ve test sonuçları ile gösterilmiştir. Elastomer malzemeler hiperelastik ve viskoelastik özelliklerinden dolayı kuvvete, zamana, sıcaklığa, malzeme özellikleri gibi birçok değişkene bağlı olarak metal malzemelerden farklı tepkiler gösterirler. Sürüş güvenliği, mekanik sağlamlık ve ürün ömrü otomobillerde garanti altına alınması gereken konulardır, bu sebeple yüksek dinamik ve termal yüklere maruz kalan debriyaj sisteminde elastomer yay rijitliği için güvenlik faktörü seçiminde yapılması gereken yaklaşımlar da ortaya konulmuştur. Elastomer yay malzeme testleri, son ürün testleri ve sonlu elemanlar analizi ile doğrulanmasının ardından komple otomobil güç aktarım sistemi bir boyutlu modellenerek sistem davranışları karşılaştırmalı olarak incelenmiştir. Tasarım ve doğrulama aşamalarının ardından hiperelastik ve viskoelastik davranışları karakterize edilen elastomer damper yayının tasarım ve sistem optimizasyonları gerçekleştirilmiştir. Optimizasyon algoritmalarında 'Tavlama Benzetimi' algoritması uygulanarak geometrik kısıtlar için algoritma geliştirilmiştir ve Python dilinde kodlama yapılmıştır. Güç aktarım sistemi optimizasyonunda, 'Tavlama Benzetimi' algoritması bir boyutlu modelleme ile entegre edilerek sistem üzerinde titreşim optimizasyonu uygulanmıştır ve optimum sistem titreşim çıktıları elde edilmiştir. Otomobil debriyaj sistemleri için elastomer yayların incelenmesi ve bu yayların güç aktarım sistemi için optimizasyonu bu alanda yapılan yeni bir çalışma olup, alternatif malzemelerin yeni nesil otomobillere adaptasyonu ve uygulanması konusunda temel oluşturabilecek niteliktedir.
Increased comfort requirements on vehicles have been revealed that optimum system design and long product life necessities. In this thesis study, the using of elastomer based materials as damping element have been investigated by taking into consideration of design, validation with bench tests, design and system optimization phases. In the studies, the comparison has been performed with the traditional metallic helical springs, and the advantages and disadvantages of the systems with elastomer springs and metallic springs were revealed with analysis and test results. Due to their hyperelastic and viscoelastic properties, the elastomer materials react unlike to metal materials depending on many variables such as strength, time, temperature and material properties. Driving safety, mechanical endurance, and product life are the issues that need to be guaranteed, hence also the approaches on the selection of safety factor for elastomer spring stiffness have been revealed on the clutch system that is subjected to high dynamic and thermal forces. After the material testings have been validated with final product testings and FEA study, complete powertrain system was 1-D modeled, and system behaviors had been investigated comparatively. Following to design and validation phases, the design and system optimizations of elastomer damper spring, at which the hyperelastic and viscoelastic behaviors are characterized, have been performed. Between the optimization algorithms, the Simulated Annealing (SA) algorithm have been selected and performed by developing the code depending on with geometrical constraints and the coding was provided in Python language. On the powertrain system optimization, SA algorithm was integrated with 1-D modeling and the vibration optimization has been performed on the system. Then, the optimum vibration outputs were obtained. The investigation of elastomer damper springs and the optimization of this springs to the powertrain system are the new study in this spesific area and enable to obtain of basics amongst to adaptation and applying of alternative materials to the new generation vehicles.
Increased comfort requirements on vehicles have been revealed that optimum system design and long product life necessities. In this thesis study, the using of elastomer based materials as damping element have been investigated by taking into consideration of design, validation with bench tests, design and system optimization phases. In the studies, the comparison has been performed with the traditional metallic helical springs, and the advantages and disadvantages of the systems with elastomer springs and metallic springs were revealed with analysis and test results. Due to their hyperelastic and viscoelastic properties, the elastomer materials react unlike to metal materials depending on many variables such as strength, time, temperature and material properties. Driving safety, mechanical endurance, and product life are the issues that need to be guaranteed, hence also the approaches on the selection of safety factor for elastomer spring stiffness have been revealed on the clutch system that is subjected to high dynamic and thermal forces. After the material testings have been validated with final product testings and FEA study, complete powertrain system was 1-D modeled, and system behaviors had been investigated comparatively. Following to design and validation phases, the design and system optimizations of elastomer damper spring, at which the hyperelastic and viscoelastic behaviors are characterized, have been performed. Between the optimization algorithms, the Simulated Annealing (SA) algorithm have been selected and performed by developing the code depending on with geometrical constraints and the coding was provided in Python language. On the powertrain system optimization, SA algorithm was integrated with 1-D modeling and the vibration optimization has been performed on the system. Then, the optimum vibration outputs were obtained. The investigation of elastomer damper springs and the optimization of this springs to the powertrain system are the new study in this spesific area and enable to obtain of basics amongst to adaptation and applying of alternative materials to the new generation vehicles.
Description
Keywords
Elastomer damper yayı, Şekil optimizasyonu, Debriyaj, Güç aktarım sistemi, Tavlama benzetimi algoritması, Bir boyutlu modelleme, Sistem optimizasyonu, Elastomer damper spring, Shape optimization, Clutch, Powertrain system, Simulated annealing algorithm, 1-D modeling, System optimization
Citation
Genç, M. O. (2019). Otomobil debriyajları için elastomerik damperin modellenmesi, analizleri ve doğrulanması. Yayınlanmamış doktora tezi. Bursa Uludağ Üniversitesi Fen Bilimleri Enstitüsü.