Investigation of Feasible Nozzle Configurations for NOise Reduction in Turbofan and Turbojet Aircraft. Volume III. Shrouded Slot Nozzle Configurations.
Abstract
This report presents the results of a study of the acoustic and fluid dynamic characteristics of a shrouded slot nozzle. Experiments were carried out on a slot nozzle of aspect ratio 27 with an ejector shroud having a cross sectional area of four times the primary nozzle area. Parameters varied during the tests were, shroud length, shroud divergence ratio, and acoustical impedance of the shroud wall. Tests were conducted for primary flow Mach numbers from 0.5 to choking and stagnation temperatures from ambient to 1200 R. The results of the study show that both the thrust and the noise attenuation characteristics of the ejector shroud improve with increasing length. Thrust increases of near 40% were obtained for the longest shroud tested. A noise reduction of 13 dB was obtained for the lined shroud with a near choked, high temperature primary jet. The corresponding thrust augmentation was approximately 20%. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1977
- Accession Number
- ADA041782
Entities
People
- B. H. Goethert
- J. R. Maus
- M. C. Joshi
- V. Veerasamy
- William A. Dunnill
Organizations
- University of Tennessee Space Institute