Ducted propeller and fan-in-wing configurations

The ducted propeller and the fan-in-wing configurations are somewhat similar in that the flow through the rotating propulsor in each case is influenced by an external surface. The two configurations are given in Fig. 9-1. For V/STOL applications the ducted propeller may be rotated through an angle of attack of 90°. The fan-in-wing, however, operates mostly at only small angles of attack of the wing. In analyzing the ducted propeller, we must consider the interaction between the duct and the pro­peller. Similarly, the influence of the fan and wing on each other must be considered in any analysis of the fan-in-wing configuration. Let us consider first the ducted propeller.