EFFECT OF MULTIPLE-NOZZLE GEOMETRY ON JET-NOISE GENERATION
Abstract
An experimental investigation was conducted in order to determine the effect of changes in the geometry of multijet nozzles on noise generation. Jet-pressure ratios of 1.67 and 2.33 were investigated for three-, five-, and seven-nozzle configurations with nozzle widths of 0.5, 0.75, 1.0, and 1.25 inches and spacings of 0.5, 1.0, and 1.5 inches. Test results showed that minimum power ratios were obtained at spacing ratios of 2.0 and 1.5 at subsonic and supersonic pressure ratios, respectively. Full-scale test results are in good agreement with the established curves. Significant reductions in the intensity of power-spectrum levels at the low- and midfrequency portions of the spectral distribution curve accompany a change in geometrical configuration of multiple nozzles to one with a minimum power ratio. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1961
- Accession Number
- AD0262410
Entities
People
- Vern G. Rollin
Organizations
- National Aeronautics and Space Administration