Acceleration potential techniques from three-dimensional thin wing theory have been generalized for propeller and prop-fan analysis. Helicoidal reference surfaces take the place of the planar surface in wing theories; otherwise the theories are equivalent. The acoustic branch of the theory, including nonlinear source terms, extends and unifies frequency domain noise theories dating back to Gutin. For aerodynamic applications, it is shown that prop,-fans satisfy well-known criteria for use of linearized theory at transonic speeds by virtue of small aspect ratio and small thickness ratio. The results are in the form of integral equations for downwash as functions of thickness and steady or unsteady loading distributions. For the case of no rotation, the kernel functions reduce to well-known kernels of wing theory. The analysis, within the restrictions of linearization, treats rigorously any planform and any flight condition including the combination of subsonic roots and supersonic tips typical of prop-fans. The effects of thickness, camber, angle of attack, sweep, offset, blade interference, and tip relief are all treated without approximation.
Compressible helicoidal surface theory for propeller aerodynamics and noise
Kompressible-Schraubenflaechentheorie zur Untersuchung der Aerodynamik und der Geraeusche von Luftschrauben
AIAA Journal ; 21 , 6 ; 881-889
1983
9 Seiten, 4 Bilder, 30 Quellen
Article (Journal)
English
NTIS | 1956
|Springer Verlag | 2012
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