Acoustical Evaluation of Two Durastick Ground Run-Up Noise Suppressors
Abstract
Measurements of the noise characteristics of two Durastack noise suppressor systems are reported. The only difference in the two systems is the acoustical treatment of the secondary air intake. Type A suppressor has essentially no acoustical treatment in the secondary air intake while Type B is acoustically treated. Measurements in octave bands taken on a 25-foot circle and at close-in positions are presented. Average noise reduction of both types of suppressors is fairly flat above the first octave band. The average value of the noise reduction from 75 to 10,000 cps is about 14 db for the Type A noise suppressor and about 21 db for the Type B noise suppressor. No intake suppressor was used. The relative magnitude of the major noise sources of the aircraft suppressor is also presented. Some non-acoustical aspects of the noise suppressors are included.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1961
- Accession Number
- AD0273987
Entities
People
- Norman Doelling
Organizations
- BBN Technologies