| タイトル | Measurement of Screen-Size Effects on Intensity, Scale, and Spectrum of Turbulence in a Free Subsonic Jet |
| 本文（外部サイト） | http://hdl.handle.net/2060/19980228013 |
| 著者（英） | Laurence, James C.; Howard, Charles D. |
| 著者所属（英） | NASA Lewis Research Center |
| 発行日 | 1960-08-01 |
| 言語 | eng |
| 内容記述 | The results are reported of hot-wire anemometer measurements of the fluctuating longitudinal component of the turbulent velocities in the mean flow downstream of screens in an air jet. These measurements have been analyzed by well-established techniques to give the influence of tile screen mesh size on the turbulent intensity, scale, and the power-spectral-density. The results show a linear dependence of the intensity upon the screen mesh size for locations within the central core of the air jet. The spectral-density curves show that the screens redistribute the turbulent energy from the low frequencies (<1000 cps) to the high frequencies (>1000 cps). The effects of the screens are overwhelmed in the mixing region of the jet flow by the turbulence levels existing there. The large pressure drops occurring across the screens reduce the velocity of the jet as compared to the jet without screens by approximately one-third for the velocity and range of mesh sizes investigated and reported in this report. The turbulence scale is a linear function of distance from the nozzle exit and is somewhat greater than comparable jets without screens. |
| NASA分類 | Fluid Mechanics and Heat Transfer |
| レポートNO | NASA-TN-D-297
E-798 |
| 権利 | No Copyright |
