| タイトル | Study of natural convection and interface shape in directional solidification of succinonitrile |
| 著者（英） | Stojanovic, M.; De Groh, H. C.; Ojah, M.; Kawaji, M. |
| 著者所属（英） | NASA Lewis Research Center |
| 発行日 | 1992-01-01
1992 |
| 言語 | eng |
| 内容記述 | Flow visualization experiments in a Bridgman furnace at zero growth velocity have been performed. The experiments were intended to investigate if the photochromic dye activation method could be used in a crystal growth study. The results from this work have confirmed that with a carefully designed experimental setup, the photochromic-dye method permits qualitative and quantitative evaluation of the flow field near the interface in crystal growth experiments. For the horizontal orientation of a 6 mm x 6 mm ampoule and an axial temperature gradient of 26.5 C/cm, velocity profiles have been obtained accurately at various positions near the interface. The maximum velocity of 1.29 mm/sec was measured in the central vertical plane and the flow was symmetrical about that plane. A flow inversion point was also noted, above which the flow was towards the interface and below it, away from the interface. The results obtained are useful for validating 3-dimensional numerical models and establishing a link between the macroscopic processing conditions and the formation of crystalline defects. |
| NASA分類 | MATERIALS PROCESSING |
| レポートNO | 95A82622 |
| 権利 | Copyright |
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