Comparison of heat transfer to hydrogen, deuterium, and neon boiling with free convection at atmospheric pressure
✍ Scribed by J.M. Astruc; A. Lacaze; P. Perroud
- Publisher
- Elsevier Science
- Year
- 1969
- Tongue
- English
- Weight
- 230 KB
- Volume
- 9
- Category
- Article
- ISSN
- 0011-2275
No coin nor oath required. For personal study only.
✦ Synopsis
Experimental results on thermal exchange by free convection at atmospheric pressure are described. They have been measured in the same experimental arrangement for liquid neon, deuterium, and hydrogen. The exchange surface consists of a platinum wire of 0.015 cm diameter and 49 cm effective length, heated by a direct current. For all three fluids, the region of free convection without boiling (heat flow less than approximately 0.2 W/cm 2) is described fairly well by the classical relation Nu = a(GrPr) n. The nucleate boiling region appears between 0.2 and 0.4 W/cm 2 for all three fluids. For deuterium, and especially for neon, the Kutateladze relation, useful in this region of heat exchange, gives temperature steps between fluid and wall, which are greater than the experimentally observed values. The experimental values of critical heat flux in the three fluids as well as the corresponding temperature steps are comparable to each other, (Ne: 6 W/cm z and 2.8 K; D2: 6.2 W/cm 2 and 2.4 K; H2: 5.2 W/cm 2 and 2K).