Reduced order modeling of helicopter substructures for dynamic analysis

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Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Havacılık ve Uzay Mühendisliği Bölümü, Türkiye

Tezin Onay Tarihi: 2018

Öğrenci: UĞUR HAYIRLI

Danışman: ALTAN KAYRAN

Özet:

Dynamic analysis of a structure is generally conducted by the finite element method in aerospace structures. The models usually contain large number of elements to be able to obtain more accurate results. Although the most computers are capable of solving the large and complex problems, the analysis problems such as dynamic optimization, aeroelastic, frequency and time response may take long time due to involving iterative and multi-step processes. In this study, various model reduction methods are described in order to achieve faster solutions by decreasing the size of the finite element model and preserving the dynamic behavior of the structure. The reduction techniques are categorized under three different approaches namely reduction of system matrices, component mode synthesis and stick model development. In this study, the techniques used to create the reduced models are reviewed in detail and the capability of the methods to reflect the dynamic behavior of the global structure is investigated. A simple cantilever plate and a typical helicopter tail finite element models are utilized to perform the reduction procedure and to verify the presented methodologies. The results of the normal modes, frequency and time response analyses are compared with the full/global finite element models to demonstrate the efficiency of the reduction techniques.