Aerodynamic Force Optimization for Aircraft

Is known that aeroservoelasticity is a multidisciplinary study for the interactions of three disciplines used in the Fly By Wire aircraft design studies. These disciplines are: the unsteady aerodynamics, the aeroelasticity and the servo-controls applied on an aircraft. An aspect of the aeroservoelasticity is the conversion of unsteady aerodynamic forces from the frequency domain (aeroelasticity) into Laplace domain (aeroservoelasticity). Flexible aircraft structure is modeled by finite elements methods by use of classical finite elements NASTRAN software. The aircraft aerodynamics is modeled by use of the Doublet Lattice Method DLM in the subsonic regime. Aerodynamic forces are optimized for a range of reduced frequencies and will be converted from the frequency into Laplace domain for aeroservoelastic interactions studies by use of a new optimization method here presented. The application of modern control design techniques, simulation and optimization procedures to aeroservoelastic systems require the aeroservoelastic equations of motion to be transformed into a first-order, time-domain (state-space) form. In order to achieve this goal the unsteady aerodynamic forces must be linearized using an approximation in the frequency domain by rational functions of the Laplace variable