A two-degree-of-freedom airfoil with a freeplay non-linearity in the pitch and plunge directions has been analyzed in the transonic and low-supersonic #ow region, where aerodynamic non-linearities also exist. The primary purpose of this study is to show aeroelastic characteristics due to freeplay st
AEROELASTIC ANALYSIS OF A FLEXIBLE AIRFOIL WITH A FREEPLAY NON-LINEARITY
β Scribed by S.-H. Kim; I. Lee
- Publisher
- Elsevier Science
- Year
- 1996
- Tongue
- English
- Weight
- 761 KB
- Volume
- 193
- Category
- Article
- ISSN
- 0022-460X
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β¦ Synopsis
A two-dimensional flexible airfoil with a freeplay non-linearity in pitch has been analyzed in the subsonic flow range. Structurally, the airfoil is modelled as finite beam elements and two spring elemens in pitch and plunge. A doublet lattice method is used for the two-dimensional unsteady aerodynamics to include the camber deflection effect. The fictitious mass modal approach is adopted in order to use the consistent modal co-ordinates for the structures with non-linearity. Non-linear aeroelastic analyses for both the frequency domain and time domain are performed for rigid and flexible airfoil models to investigate the flexibility effect. Results are shown for models of different pitch-to-plunge frequency ratio. Responses involving limit cycle oscillation and chaotic motion are observed and they are highly influenced by the pitch-to-plunge frequency ratio.
π SIMILAR VOLUMES
A three degree-of-freedom aeroelastic typical section with control surface freeplay is modeled theoretically as a system of piecewise linear state-space models . The system response is determined by time marching of the governing equations using a standard Runge -Kutta algorithm in conjunction with
A two-dimensional airfoil with either a bilinear or cubic structural nonlinearity in pitch, and subject to incompressible flow has been analysed; the aerodynamic forces on the airfoil are evaluated using Wagner's function. The resulting equations are either integrated numerically using a finite diff