Aerodynamic design and evaluation of an open-nose supersonic drone

Abstract

The objective of this paper is to investigate the efficiency of a proposed supersonic drone configuration, in terms of drag, ram recovery, and fundamental flight performance factors. Sustainable supersonic cruise at Mach 1.6 is the major segment of the mission profile which affects the overall geometry resulting from the conceptual design phase, a tailless delta drone with an open-nose forebody, lofted around the inlet which consists of an analytical compression surface and a S-duct diffuser. Because the aerodynamics of this unconventional configuration is unknown, a series of CFD simulations using the ANSYS Fluent solver is coupled to the design process to predict both internal and external aerodynamics as a proof of the concept. The simulations indicate that the drone’s overall drag is significantly lower than the other configurations with side or underside integrated inlets while the inlet pressure recovery is adjusted to maximize the engine thrust. The parasite drag at design speed is about 0.022 which is considerably lower than conventional configurations and the pressure recovery more than 0.96 is possible by applying the boundary layer bypass. A comparative study, with a developed thrust model, shows that the configuration satisfies mission requirements and exceeds them at transonic and supersonic flight phases.