A thin, low cambered aerofoil with a tab at the
trailing edge in inviscid, incompressible,
two-dimensional, unstalled flow with varying
freestream velocity and arbitrary, different motions
for both aerofoil and tab is considered. The general
expressions for unsteady lift and aerodynamic moment
on aerofoil and tab are derived within the
assumptions of potential theory.
To verify the approach proposed in this paper, the
classical Theodorsen case of an oscillating aerofoil
is adopted. For this case, aerofoil loads are
calculated in the time domain by applying an inverse
Laplace transformation to the approximation of the
lift deficiency function in the frequency
domain.
The comparison of the results calculated by this method
with those obtained by other methods and experiments
shows good agreement, which validates the general
formulation. The loads on an aerofoil having
different frequencies for main aerofoil pitch and
tab deflection are calculated.