The research on a single autorotating flat-plate has been studied in the literature analytically and experimentally.
In this experimental research, a second flat-plate wing is placed upstream of a main wing in order to see the aerodynamic effect of the second wing on the primary.
It is learned that the angle of attact of the second wing, when it is fixed, has great influence on the characteristics of autorotation and aerodynamic forces on the primary wing.
In the case, the flow incident on the primary wing is unevenly accelerated by the upstream second.
For the case, when the second wing is autorotating, the primary wing is also influenced a great deal in its own autorotation. The condition of autorotation for the both of the plates is that they should rotate in the same direction.
We expressed the measurement of autorotating characteristics in terms of Strouhal number, rotating frequency, Reynoldys number, maximum and minimum lift and drag coefficients, and the time distribution of the local lift and drag coefficients.
