  This Note determines the unsteady non-circulatory forces on an arbitrarily
deforming panel with a Holder-continuous porosity distribution. An analytical
expression for the non-circulatory pressure distribution is presented and
evaluated for the special cases of uniform and variable-porosity panels
undergoing harmonic deformations, where special attention is paid to the
influence of the panel end conditions. These results constitute the first major
step towards a complete linearized, unsteady aerodynamic theory for lifting
porous bodies, which may have potential application to the performance
estimation of biologically-inspired swimmers and fliers and to the future
assessment of aeroelastic stability and flow noise production of porous
airfoils.
