论文信息 - The problem of noise reduction with reference to light airplanes

The problem of noise reduction with reference to light airplanes

From Summary: "Experiments by Deming at the Langley Memorial Aeronautical Laboratory confirm completely the formula of Gutin, which permits the convenient calculation of the sound level of any airplane propeller at low forward speeds. A simplification of the Gutin formula has been achieved by the use of a set of functions giving the sound level in the direction of maximum intensity. The sound level can be read from graphs of the functions for various numbers of blades and tip speeds. Two numerical examples and one experimental example are included; also, a radical fan-type propeller is tentatively treated."

Arthur A. Regier | Theodore Theodorsen

[1] Theodore Theodorsen. The theory of propellers I : determination of the circulation function and the mass coefficient for dual-rotating propellers , 1944 .