State Space Representation of Smart Structures Under Unsteady Aerodynamic Loading

2007-09-10
Fatih Mutlu, Karadal
Güçlü, Seber
Şahin, Melin
Volkan, Nalbantoğlu
Yaman, Yavuz
This study presents a technique for the state space representation of the aeroelastic models of smart structures. It was based on a rational approximation of the unsteady aerodynamic loads in the Laplace domain, which yielded state-space matrix equations of motion with constant coefficients. In this study, an aluminum plate-like structure with twenty-four surface bonded piezoelectric patches was considered. The unsteady aerodynamic loads acting on the structure were calculated for a range of reduced frequencies and a Mach number by using a linear two-dimensional Doublet-Lattice Method available in MSC/NASTRAN®. Those discrete air loads were approximated as rational functions of the Laplace variable by using one of the aerodynamic approximation schemes, Roger’s approximation, with least-squares method. Then the state space representation of the aeroelastic model was constructed by using the approximated air loads together with structural matrices. In order to verify the state space approach, the flutter characteristics of the plate-like structure were investigated and the results were compared to those obtained by MSC/NASTRAN® analysis.
4. Ankara International Aerospace Conference, 2007

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Citation Formats
K. Fatih Mutlu, S. Güçlü, M. Şahin, N. Volkan, and Y. Yaman, “State Space Representation of Smart Structures Under Unsteady Aerodynamic Loading,” presented at the 4. Ankara International Aerospace Conference, 2007, Ankara, Turkey, 2007, Accessed: 00, 2021. [Online]. Available: aiac.metu.edu.tr.