A Preliminary Study Of Potential Advantages Of Non-Uniform Extended Fan Ducts Using Computational Fluid Dynamics
The enhancement effect of a shroud or duct surrounding a propeller or multi-bladed fan is well known and has
long been a mainstay of aircraft propulsion. Computational Fluid Dynamics modelling using FLUENT and an laminar,
incompressible flow has suggested that moderate enhancements could be achieved by extending the duct in a non-uniform
manner,(more colloquially referred to as a “lip wing”). Not only does the wing generate a minor resultant force with a
component in the direction of the thrust, it also improves the fan thrust. Though this effect is heavily dependent on the
geometry of the wing and the angle the lip wing makes with the axis of the rotor, thrust can improve by almost 12%
compared to a similar actuator disc without a lip wing and shroud.
Keywords- CFD, Incompressible and Laminar Flow, Aerodynamics, Lip-Wing.