Accession Number:

AD0257424

Title:

PROPELLER SINGING ANALYSIS

Descriptive Note:

Corporate Author:

GENERAL APPLIED SCIENCE LABS INC HEMPSTEAD N Y

Personal Author(s):

Report Date:

1961-03-01

Pagination or Media Count:

1.0

Abstract:

A theoretical investigation is presented of the phenomenon of singing of moving hydrofoil vanes or blades. The experimentally noted dependence of Strouhal frequency on blade thickness, bound-ARY LAYER THICKNESS AND VIBRATION AMPLITUDE IS TAKEN INTO CONSIDERATION IN FORMULATING AN EXPRESSION FOR THE HYDRODYNAMIC FORCES ACTING ON THE BLADE. The unsteady hydrodynamic forces associated with an oscillating blade are generalized by relinquishing the Kutta condition of boundedness of pressure jump at the blade trailing edge. Curves of frequency and amplitude versus velocity were obtained which bear good qualitative resemblance with available experiment. The effect of trailing edge thickness is also examined and indicates frequency and amplitude effects consistent with experiment. The sound field intensity and distribution is discussed and an estimate obtained. Author

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE