| タイトル | Investigation of the aerodynamic noise generating region of a jet engine by means of the simple source fluid dilatation model |
| 著者（英） | Meecham, W. C.; Hodder, B. K.; Hurdle, P. M. |
| 発行日 | 1974-12-01 |
| 言語 | eng |
| 内容記述 | An experiment was conducted on a full-scale jet engine to investigate the aerodynamic noise generating regions in the free jet. Cross-correlation measurements were made between the static pressure fluctuations and the farfield radiated sound. These measurements were made for two different static pressure probe positions and a large number of farfield positions (at various angles). In addition, each test geometry was run for four different jet exit velocities. The measured, normalized cross-correlation functions varied between 0.004 and 0.155. A new Q-function, based on the above normalized cross correlation is defined and plotted. This function represents the source strength per unit volume within the jet region. This Q-function shows dependence on the probe position, the angular position of the farfield microphone, and the jet exit Mach number. Third-octave analyses of both the probe signal and the farfield radiated sound were made. The results show that cross-correlation techniques are a valuable tool in the investigation of the aerodynamic noise generating regions of an actual jet engine. |
| NASA分類 | AIRCRAFT PROPULSION AND POWER |
| レポートNO | 75A20119 |
| 権利 | Copyright |
| URI | https://repository.exst.jaxa.jp/dspace/handle/a-is/449335 |
|
