Location of Repository

Supersonic Jet Noise Reduction by Coaxial Jets with Coplanar and Staggered Exits

By D. S. Dosanjh, Thompson Matambo and Morteza Gharib


Far-field noise radiated from coaxial cold underexpanded\ud jet flows issuing from convergent two-nozzle\ud configurations with coplanar and staggered-exits\ud is investigated experimentally. The coaxial\ud jets are operated in the "inverted" mode, i.e., the\ud outer (annular) jet flow Mach number is higher than\ud that of the inner (round) jet. Keeping all other\ud geometrical and operating conditions the same, the\ud exit-stagger of the inner (round) and the outer\ud (annular) nozzles was varied. It is shown that the\ud extent of the exit-stagger affects both the flows\ud and the radiated noise from such coaxial underexpanded\ud jet flows and that comparatively, the lowest\ud noise levels are achieved when the coaxial nozzle-exits\ud are coplanar. Moreover, the effectiveness\ud of the co-flowing inner jet flow in reducing the\ud noise radiated from either the annular or the coaxial\ud underexpanded jet flows decreases noticeably\ud as the exit-stagger is increased

Publisher: American Institute of Aeronautics and Astronautics
Year: 1979
OAI identifier: oai:authors.library.caltech.edu:41304
Provided by: Caltech Authors

Suggested articles


To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.