Effects of riblets on the performances of a regional aircraft configuration in NLF conditions

The application of the riblets to a typical regional turbo-prop configuration is discussed in this paper. The effect of the riblets is modelled as a singular roughness problem by a proper boundary condition proposed by University of Napoli. The model is described and first its application to 2D flows is presented. Then a typical wing-body of a regional aircraft is considered. The configuration has been designed to have a natural laminar flow for a large extent of the wing in cruise conditions. Riblets are applied at flow specifi- cations representative of cruise in combination with the laminar flow technology and in climb/descent conditions. The save of fuel achievable in a typical operative day of such an aircraft has been also estimated.