Semi-Empirical Simulation Of Steady And Unsteady Rotor Blade Aerodynamic Loading

A general formulation was develooed to simulate the aerodynamic coefficients of a rotor blade at arbitrary angles of attack and Mach numbers by analytical expressions in steady and unsteady flow. The real aerodynamic behaviour is simulated by the superposition of different flow types. Theory for a flat plate is the basis for the semi-empirical load simulation of arbitrary shapes. Only this physical superposition principle of steady flow enables a consistent formulation of unsteady effects. The difference between the method and measurement data is within the measurement accuracy. The comparison with other methods indicates a significant progress. The modular form of the model allows any refinement without any change of structure. In some cases analytical integration in radial direction is possible.