Dynamics of a vapor bubble on a heated substrate

A study of high-pressure bubble growth within liquid droplets heated to their limits of superheat is reported. Droplets of an organic liquid (n-octane) were heated in an immiscible nonvolatile field liquid (glycerine) until they began to boil. High-speed cine photography was used for recording the qualitative aspects of boiling intensity and for obtaining some basic bubble growth data which have not been previously reported. The intensity of droplet boiling was found to be strongly dependent on ambient pressure. At atmospheric pressure the droplets boiled in a comparatively violent manner. At higher pressures photographic evidence revealed a two-phase droplet configuration consisting of an expanding vapor bubble beneath which was suspended a pool of the vaporizing liquid. A qualitative theory for growth of the two-phase droplet was based on assuming that heat for vaporizing the volatile liquid was transferred across a thin thermal boundary layer surrounding the vapor bubble. Measured droplet radii were found to be in relatively good agreement with predicted radii.

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“Pressure Blocking” Effect in the Growing Vapor Bubble in a Highly Superheated Liquid

Journal of Engineering Physics and Thermophysics ◽

10.1007/s10891-016-1477-6 ◽

2016 ◽

Vol 89 (5) ◽

pp. 1141-1151 ◽

Cited By ~ 1

Author(s):

Yu. B. Zudin ◽

V. V. Zenin

Keyword(s):

Vapor Bubble ◽

Blocking Effect ◽

Superheated Liquid

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Vapor bubble growth in heterogeneous boiling—I. Formulation

International Journal of Heat and Mass Transfer ◽

10.1016/0017-9310(94)00195-2 ◽

1995 ◽

Vol 38 (5) ◽

pp. 909-919 ◽

Cited By ~ 47

Author(s):

Renwei Mei ◽

Wenchin Chen ◽

James F. Klausner

Keyword(s):

Vapor Bubble ◽

Bubble Growth

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Evaporation of Single Drops of n-Pentane/n-Hexane Mixtures in Water

Journal of Heat Transfer ◽

10.1115/1.2911908 ◽

1992 ◽

Vol 114 (4) ◽

pp. 965-971 ◽

Cited By ~ 3

Author(s):

H. Shimaoka ◽

Y. H. Mori

Keyword(s):

Heat Transfer ◽

Temperature Difference ◽

Vapor Bubble ◽

Experimental Results ◽

Rise Velocity ◽

Heat Transfer Characteristics ◽

Two Phase ◽

Transfer Characteristics ◽

Preceding Work ◽

Liquid Vapor

The evaporation of isolated drops (2.1−3.0 mm diameter) of nonazeotropic n-pentane/n-hexane mixtures in the medium of water was observed under pressures of 0.11−0.46 MPa and temperature differences up to 27 K. The mole fractions of n-pentane, x, in the mixtures were set at 0.9, 0.5, 0.1, and 0, to be completed by the condition x = 1 set in a preceding work (Shimaoka and Mori, 1990). Experimental results are presented in terms of the instantaneous rise velocity of, and an expression of instantaneous heat transfer to, each drop evaporating and thereby transforming into a liquid/vapor two-phase bubble and finally into a vapor bubble. The dependencies of the heat transfer characteristics on the pressure, the temperature difference, and x are discussed.

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