Particulate Erosion Predictions for Helicopter Rotor Blades

An analytical erosion prediction capability will be developed for helicopter rotor blades exposed to sandy environments and rain. The overall problem is divided into five components each requiring its own input parameters and computational tools. These five components are: characterization of the aerodynamic flow fields created by helicopter rotor blades, establishment of the particle impact conditions associated with these flow fields, formulation of computational mechanics descriptions for the particle interactions with a rotor blade, introduction of criteria for damage initiation, growth, and material removal, and development of methods to predict material removal from an eroding surface. The Phase I effort will consider conventional and innovative approaches that can be pursued for each of these components. They will be evaluated in terms of their implementation, preserving the physically significant features in each component, and their compatibility with the approaches for the other components. The input required for each component will be identified and refined as the program proceeds into Phase II where the general methodology will be acted upon using the most relevant computer codes and the input required collected from the existing literature to the extent that it is available. Work on all five components can be carried out simultaneously since they require input from a number of different fields.