Experimental and calculated temperature and mass histories of vaporizing fuel drops / M.M. El Wakil [and others]
The present report compares experimental and calculated mass and temperature histories of drops vaporizing with a constant velocity relative to the air and confirms the thought that, under many conditions, the unsteady state or time required for the drop to reach the wet-bulb temperature is an appre...
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| Format: | Government Document Book |
| Language: | English |
| Published: |
Washington, D.C. :
National Advisory Committee for Aeronautics,
[1956]
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| Series: | Technical note (United States. National Advisory Committee for Aeronautics) ;
3490. |
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| Summary: | The present report compares experimental and calculated mass and temperature histories of drops vaporizing with a constant velocity relative to the air and confirms the thought that, under many conditions, the unsteady state or time required for the drop to reach the wet-bulb temperature is an appreciable portion of the total vaporization time. Work was done to verify or disprove the assumptions used in the computations. Data are presented to show that the assumption of infinite thermal conductivity is valid primarily because of circulation inside the drop. The presence of this circulation was verified by hlgh-speed motion pictures. The need for a correction factor to the heat transfer to express the effect of mass transfer on heat transfer was confirmed as well as the need for a correction factor to correct for unidirectional (as opposed to equimolal) diffusion. A few preliminary temperature histories of the vaporizing drops of binary mixtures were also taken as well as a few histories of drops of different fuels vaporizing in air at sufficiently high temperatures that burning of the drops took place. While precise temperature histories were not obtained the measured steady-state temperatures were close to the boiling temperatures when burning occurred. |
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| Item Description: | "January 1956." NACA TN Number 3490. Other authors include: R.J. Priem, H.J. Brikowski, P.S. Meyers, and O.A. Uyehara. |
| Physical Description: | 82 pages : illustrations ; 27 cm. |
| Bibliography: | Includes bibliographical references. |