Abo Bibliothek: Guest

ISSN Online: 2377-424X

International Heat Transfer Conference 5
September, 3-7, 1974, Tokyo, Japan

AXIAL PROPAGATION OF FREE SURFACE BOILING INTO SUPERHEATED LIQUIDS IN VERTICAL TUBES

Get access (open in a dialog) DOI: 10.1615/IHTC5.140
pages 30-34

Abstrakt

A unique free surface boiling phenomenon has been observed as a result of rapid depressurization of an initially saturated or slightly subcooled stagnant liquid column in the absence of wall and bulk nucleation sites. Closeup high-speed photographs of water, refrigerant-11, and methyl alcohol in tubes from 0.2 to 15 in. diameter reveal that the initiation of violent free surface flashing (vapor plus entrained liquid) follows from the development of Marangoni-type surface waves. The rate of propagation of the flashing surface shows evidence of choked flow limitations and proceeds at a rate which is several orders of magnitude greater than surface evaporation (vapor only) alone. The onset of free surface flashing was found to be dependent upon both the degree of initial liquid superheat and the tube diameter.