| Title | Investigation of Jet Noise Using Optical Holography |
|---|---|
| Record ID | 48626 |
| Personal Name Creator |
Salant, Richard F. |
| Source | 66p. in various pagings |
| Corporate Creator | John A. Volpe National Transportation Systems Center (U.S.) |
| Corporate Contributor |
United States. Department of Transportation. Federal Aviation Administration |
| Publisher | United States. Dept. of Transportation. Office of the Secretary |
| Publication Date | 19730401 |
| Language | English |
| Abstract | Holographic interferograms have been made of cold, laboratory scale, supersonic air and nitrogen jet in the mach number range of 2.1 ot 3.4, and of helium jets in the mach number range of 1.5 to 2.95. These holograms demonstrate that the acoustic field in the vicinity of such jets is dominated by mach waves, each of which can be traced back to a generating disturbance within the jet. The mach waves are generated from an axial position slightly downstream of the nozzle exit to a position near the tip of the potential core. Measurements of each angle indicate that the average convection velocity of the generating disturbances in the air/nitorgen jet is approximately 84% - 90% of the jet velocity for the mach number range of 2.1 - 2.7, and approximately 77% of the jet velocity for each mach number range of 2.8 - 3.4. |
| Rosap ID | dot:10133 |
| Rosap URL | https://rosap.ntl.bts.gov/view/dot/10133 |
| TRT Terms | Holography; Aircraft noise; Optical systems; Mach number; Jet propelled aircraft; Velocity measurement; Speed of sound; Supersonic speed |
| Classification | NTL - AVIATION - AVIATION; NTL - AVIATION - Aviation Energy and Environment; NTL - ENERGY AND ENVIRONMENT - Aviation Energy and Environment |
| Geographical Coverage |
United States |
| Report Number | DOT-TSC-OST-73-11; PB-214 112 |
| Resource type | Tech Report |
| URL | https://ntlrepository.blob.core.windows.net/lib/57000/57800/57837/investigationofj00sala.pdf |
| Format | |
| Database | NTL Digital Repository |