Thick Wings in Steady and Unsteady Flows

Applications of the unsteady vortex-lattice method in aircraft aeroelasticity and flight dynamics

“…Unsteady lifting-surface methods, such as the DLM and the UVLM, can be directly employed to model thickness by wrapping the elementary solutions around the real boundary [122]. In this case, a closed distribution of the singularities generates a singular influence coefficient matrix when using either Dirichlet or Neumann boundary conditions in 2-D, and with Neumann conditions in 3-D -which is the only possibility for the latter.…”

“…Panel methods that use combinations of sources and doublets/vortices were routinely used for the steady case, and transformed the aeroplane design process [121]. However, the effect of thicknesson overall forces such as lift and moment is second order and unless it is very large, around 30% of the chord [122], its influence is minimal in non-stationary flows. Hence it is usual to omit them in unsteady thin-aerofoil or lifting-surface theory.…”