Steady-State/Transient Performance Simulation of the Propulsion System for the Canard Rotor Wing UAV During Flight Mode Transition

Abstract

A steady-state/transient performance simulation model was newly proposed for the propulsion system of the CRW (Canard Rotor Wing) type UAV (Unmanned Aerial Vehicle) in various flight modes. The studying CRW type UAV has a new concept RPV (Remotely Piloted Vehicle) which can fly at two flight modes such as the take-off/landing and low speed forward flight mode using the rotary wing driven by the engine bypass exhaust gas and the high speed forward flight mode using the fixed wing and main engine thrust. The proposed propulsion system is consisted of the main engine system and the duct system. A flight vehicle may generally select the engine with a proper type and a specific model with acceptable thrust level to meet the flight mission in the propulsion system design phase. In this study, a turbojet engine with one spool was selected by decision of the vehicle system designer, and the duct system is composed of main duct, rotor duct, master valve, rotor tip nozzles, and variable main nozzle. In order to establish the safe operation of the propulsion system, performance simulation should be needed. In this study, a performance model of the Smart UAV propulsion system with ducts, tip jets and variable main nozzle, which has flight capability of the rotary wing mode for the take-off/landing and low speed forward flight as well as the fixed wing mode for high speed forward flight, has been newly developed. With the proposed model, steady-state performance analysis was performed at various flight modes and conditions, such as rotary wing mode, fixed wing mode, compound wing mode, altitude and flight speed. Through this analysis, it was confirmed that the engine performance simulation results without the duct system were well agreed with the engine manufacturer’s data, and the safe operation range of the proposed propulsion system was investigated at three flight modes. And the dynamic behavior of the system was modeled and simulated using the SIMULINK®.