Accession Number : ADA338190

Title :   Reference Manual on the Theory of Lifting Surface Noise at Low Mach Numbers

Descriptive Note : Final rept. 1 Jul-31 Dec 97

Corporate Author : BOSTON UNIV MA COLL OF ENGINEERING

Personal Author(s) : Howe, Michael S.

PDF Url : ADA338190

Report Date : 09 JAN 1998

Pagination or Media Count : 98

Abstract : A summary review is made of the theory of aerodynamic sound in low Mach number flows, with particular emphasis on procedures for estimating the influence of solid boundaries on sound production. Special consideration is given to the production of sound by nominally steady flow over a lifting or control surface. Four categories of interactions are discussed involving (1) a large, nominally flat surface, (2) a large surface with a trailing edge, (3) a lifting surface of compact chord and finite span, and (4) a trailing edge with a streamwise slot or part-span flap. The results can be combined with steady state numerical predictions to express the radiation in terms of calculated mean flow properties.

Descriptors :   *LOW VELOCITY, *SOUND, *NOISE, *MACH NUMBER, *MANUALS, *AERODYNAMICS, *LIFTING SURFACES, STEADY STATE, RADIATION, ELASTIC PROPERTIES, BOUNDARY LAYER, MATHEMATICAL PREDICTION, ACOUSTICS, FLOW, GREENS FUNCTIONS, CONTROL SURFACES, STEADY FLOW, TRAILING EDGES, AERODYNAMIC SLOTS.

Subject Categories : Military Aircraft Operations
      Acoustics
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE