The increasing demand for the good performance of aircraft aerodynamics, from the fundamental understanding of flight, requires an enhanced lift. The current study aimed at appraising the high lift duct fan system for VTOL design.
High lift devices for drone of a ducted fan configuration in hovering conditions is computationally investigated using a three dimensional, steady, Reynolds-Averaged Navier-Stokes flow based on unstructured grid technology and it is based on computational fluid dynamics (CFD) using ANSYS CFX. Hence, a complete performance comparison of the Ducted fan only body and the modified Models body profile was carried out in this research.
The Models are designed in order to improve the pressure distribution over the body, hence low-pressure region is formed over the upper surface and higher pressure over the lower surface. In addition, net thrust can be generated on the duct lip due to the fan suction effect.
Suction peak (negative pressure) occurs over the duct lip will result in pressure difference reaction force (lift) of the system giving a greater performance in thrust output which satisfies the design
The lift force is the main outcome of this investigation. Parametric study of different design in various configurations has been performed to distinguish the effect of geometric parameters to the performance of the system. The results proved that the Model 3 body profile has been significantly improved. The maximum amount of lift force contribution was found to be 90% of extra lift generated by the body when compared to the ducted fan only. This is mainly because of the flow passing through upper body surface and creates a negative pressure.
Coanda Effect also takes place along the curve design of the body profile model. These have evolved to generate lift forces in a more efficient manner.
Overall the contribution of the lift takes place by pressure difference at the upper and lower surface, and duct lip. This study may provide a viable technology to improve the aerodynamic performance of ducted fan in hovering conditions.

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