Design and Performance of a Quad-Shrouded Rotor Micro Air Vehicle

Rapid Design Process of Shrouded Rotors for Efficient UAV Propulsion

“…An anemometer was used to evaluate the exit velocities of the rotor. While the thrust stand can = √ 4 ⋅ * (9) measure the rotor thrust directly, for the shrouded designs we need to consider the total thrust which constitutes of the thrust generated by the rotor and shroud as defined in Eq. (4).…”

“…All studies consistently conclude that shrouding improves the aerodynamic efficiency of the rotor compared to the open rotor configuration. However, with propeller shrouding increasingly applied to a range of multirotor configurations from very small scale [8], [9] to larger eVTOL rotors, such as the example by Airbus shown in Fig. 1, it is critical to understand how the efficiency of the shrouded rotor is driven by the rotor geometry and shroud shape.…”

Effect of Ducted Multi-Propeller Configuration on Aerodynamic Performance in Quadrotor Drone

“…The duct is composed of a rounded leading edge and a straight or tapered trailing edge formed as the inlet and diffuser section, respectively. The rotor operation generates a suction pressure gradient on the duct inlet surface, thus resulting in additional lift, which contributes to the total lift force and hence enhances the FM efficiency [10][11][12]. ), = 0, induced velocity ( ), and far wake velocity ( = 2 ), additional lift force generated by duct ( ).…”

“…The aerodynamic optimization of the ducted-propeller configuration thus consists of minimizing the propeller-duct interactions, the reduction of the duct's weight [22], the duct geometry, the tip clearance between propeller tip and the duct inwall, and so on. With respect to the ducted-propeller application in UAVs and MAVs, duct (shroud) designs with various blades, shroud dimensions, and height difference have been proposed and developed, for instance, to evaluate the hovering performance and edgewise flow experimentally [10][11][12] and computationally [23,24]. Chua, et al [25] computationally and experimentally investigated the effect of shrouded rotors on energy cost/efficiency and thrust power by altering the leading-edge lip radius (LLR), the diffuser length (DL), and the diffuser angle (DA).…”

“…For the sake of completing various missions outstandingly, it is vital for this aircraft to possess some characteristics such as high efficiency, stability, maneuverability, aerial duration, and so on. Many research studies on multirotor copters have been conducted, associated with lift force and efficiency improvement in the manner of blade optimization design [6], overlapping propellers' design at different heights [7], and multirotor design regarding rotors with a large tip distance [8], tilt [9] or shroud [10][11][12].…”