Theoretical Investigation of Static Coefficients, Stability Derivatives, and Interference for Ducted Propellers

摘要

The force and moment coefficients at angle of attack and their dynamic pitching derivatives are predicted by potential flow analysis for an isolated ducted propeller. The analysis is based upon Fourier expansion of the vorticity distribution and makes use of the previous theoretical results for ring wings at angle of attack and ducted propellers in axial flow. The present results extend those derived in detail in (AD-403 146) for a short thin cylinder surrounding a uniformly loaded actuator disk. Although the actuator disk assumption is retained, the effects of large duct chord-to-diameter ratio, and the effects of duct camber, taper, and thickness are shown on the duct coefficients and their pitching derivatives. (Author)