Review and Analysis of the DNW/Model (Duits-Nederlandse Windtunnel) 360 Rotor Acoustic Data Base

Abstract : A comprehensive model rotor aeroacoustic data base was collected in a large anechoic wind tunnel in 1986. Twenty-six microphones were positioned around the azimuth to collect acoustic data for approximately 150 different test conditions. A dynamically scaled, blade-pressure-instrumented model of the forward rotor of the BH 360 helicopter simultaneously provided blade pressures for correlation with the acoustic data. High-speed impulsive noise, blade-vortex interaction noise, low-frequency noise, and broadband noise were all captured in this extensive data base. This paper presents trends in each noise source, with important parametric variations. The purpose of this paper is to introduce this data base and illustrate its potential for predictive code validation. (jes)