A COMPUTER PROGRAM TO PREDICT ROTOR ROTATIONAL NOISE OF A STATIONARY ROTOR FROM BLADE LOADING COEFFICIENTS

摘要

A digital computer program is presented. The program calculates the rotational noise of stationary helicopter rotors based on multiple sets of measured or hypothetical high-frequency blade-loading coefficient data. The programing language used is FORTRAN IV. A description of all main and subprograms is provided so that any user possessing a FORTRAN compiler and random access capability can adapt the program to his facility.nIn the proper format, empirical or hypothetical blade surface-pressure spectra are used by the program to calculate:(1) blade station loading spectra, (2) chordwise and/or spanwise integrated blade-loading spectra, and (3) far-field rotational noise spectra. Any of five standard inline functions describing the chordwise distribution of the blade loading can be chosen in order to study parametrically the acoustic predictions.