SEMIANALYTICAL TECHNIQUE FOR SENSITIVITY ANALYSIS OF UNSTEADY AERODYNAMIC COMPUTATIONS

A semianalytical approach is developed for the sensitivity analysis of linear unsteady aerodynamic loads. The semianalytical approach is easier to implement than the analytical approach. It is also computationally less expensive than the finite-difference approach when used with panel methods that require a large number of panels. The semianalytical approach is applied to an isolated airfoil in a two-dimensional flow and rotating propfan blades in three-dimensional flow. Sensitivity coefficients with respect to non-shape-dependent variables are shown for some cases. It is expected that the semianalytical approach will be useful in aeroelastic design procedures, particularly when mistuning is present, and also that it is potentially useful for shape sensitivity analysis of linear unsteady aerodynamics.