Document Type : Research Article

Authors

1 M.Sc. Aerospace Department, Aerospace Engineering Faculty, Shahid Sattari Aeronautical University of Sciences & Technology, Tehran, Iran.

2 Associate Professor. Aerospace Department, Aerospace Engineering Faculty, Shahid Sattari Aeronautical University of Sciences & Technology, Tehran, Iran.

Abstract

In this paper, the modeling method of aircraft aerodynamic responses to the 1-cos gust profile is presented. Test cases considered are, a two-dimensional NACA0012 airfoil was used to verify the method and two-dimensional NACA23012, NACA23015, and NACA23016.5 airfoils of the wing of a light aircraft and three-dimensional wing of the same aircraft in Mach numbers 0.1, 0.2 & 0.3. The test cases are assumed to be rigid and only gust profiles are considered longitudinal. The simulation results show that the aerodynamic responses of 1-cos gust agree well with Küssner approximate function. In the two-dimensional mode for a particular airfoil, as the Mach number increases, the amplitude of the incremental lift coefficient due to the gust increases, and the wavelength decreases. As the thickness of the airfoil in a Mach number increases, the amplitude remains constant, but the wavelength increases. In the three-dimensional mode, for a wing by increasing the Mach number, the amplitude increases and the wavelength remain constant.

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