Design improvement of a versatile ducted-fan UAV

The paper discusses the aerodynamic design improvement of a ducted fan unmanned aerial vehicle (uav). the uav is capable of take-off vertically,hover and transition to cruise and is equipped with wings. the aerodynamics of the uav is estimated through wind-tunnel experiments. the design improvement is carried out for the two phases of mission profile: hover and cruise. during hover flight,modifications in propulsion system and consequent effects on the controllability of the platform are investigated. the existing single propeller motor is replaced with contra-rotating propulsion system. moreover,control surface positioning is also refined. during forward flight condition,the aerodynamic forces and moment is evaluated for plain ducted-fan configuration. it is observed that the modified configuration has the desired flight characteristics in cruise mode as well. the improvement in the aerodynamic performance with wings of different aspect ratios is also mapped out. the improvement in lift characteristics is observed with the increase in aspect ratio. © 2012 faculty of mechanical engineering,universiti teknologi mara (uitm),malaysia.