Advertisement

An Experimental Study of Evaporation Waves in a Superheated Liquid

  • L. G. Hill
  • B. Sturtevant
Part of the International Union of Theoretical and Applied Mechanics book series (IUTAM)

Summary

The dynamical behavior governing the propagation of evaporation waves in chlorinated fluorocarbons is studied in a constant-diameter vertical glass test cell which exhausts into a large, low-pressure reservoir. Care is taken to suppress heterogeneous nucleation within the liquid column. The test liquid is initially in equilibrium with its own vapor, sealed by a foil diaphragm. Upon diaphragm rupture, a series of expansion waves depressurizes the liquid to approximately the reservoir pressure, during which nucleation and subsequent rapid vaporization begin at the free surface. After an approximately 10 ms long start-up transient, a quasi-steady process develops during which the wavefront propagates into the stagnant liquid column at constant average velocity, generating a nonuniform high-speed two-phase flow. The leading edge of the wavefront consists of smooth and rough bubbles with maximum diameters of order 1 mm and characteristic lifetimes of order 1 ms. High speed movies show that the nucleation rate is both spatially nonuniform and temporally nonsteady, which leads to significant unsteadiness in the propagation of the wave. Fragmentation of the liquid into fine droplets occurs primarily as the result of the violent break-up of the leading-edge bubbles coincident with explosive bursts of aerosol, which occur in the region extending about 1 cm downstream of the leading edge bubble layer. These two processes appear to be mutually interactive. Three distinct modes of flow initiation are observed depending on the liquid superheat. Moreover, a self-initiation threshold is observed, below which waves do not occur. We observe that waves can propagate at slightly lower superheats if they are started artificially. However, an absolute threshold for wave propagation exists which is related to the nonsteady processes alluded to above.

Keywords

Reservoir Pressure Absolute Threshold Test Liquid Superheated Liquid Exit Pressure 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Bennett, F.D.; Kahl, G.D.; and Wedemeyer, E.H.; in Exploding Wires, Vol. 3, p. 65, edited by W.G. Chace and H.K. Moore, Plenum Press, New York (1964)Google Scholar
  2. 2.
    Friz, G.; Coolant ejection studies with analogy experiments, Proc. Conf. on Safety of Fast Reactors, ANL-7120, p. 890 (1965)Google Scholar
  3. 3.
    Thompson, P.A.; Chaves, H; Meier, G.E.A.; Kim, Y.-G.; and Speckmann, H.-D.; Wave splitting in a fluid of large heat capacity, J. Fluid Mech., Vol. 185, pp. 385–414 (1987)CrossRefADSGoogle Scholar
  4. 4.
    Grolmes M.A.; and Fauske, H.K.; Axial propagation of free surface boiling into superheated liquids in vertical tubes, Proc. Fifth Intl. Heat Transfer Conf., Vol. 4, pp. 30–34 (1974)ADSGoogle Scholar
  5. 5.
    Shepherd, J.E.; and Sturtevant, B.; Rapid evaporation at the superheat limit, J. Fluid Mechanics, Vol. 121, pp. 379–402 (1982)CrossRefADSGoogle Scholar
  6. 6.
    Frost, D.; and Sturtevant, B.; Effects of ambient pressure on the instability of a liquid boiling explosively at the superheat limit, J. Heat Trans., Vol. 108, pp. 418–424 (1986)CrossRefGoogle Scholar
  7. 7.
    Reynolds, W.C.; Thermodynamic properties in S.I., Dept. of Mech. Eng., Stanford Univ. (1979)Google Scholar
  8. 8.
    Winters, W.S.; and Merte, H.; Experiments and nonequilibrium analysis of pipe blowdown, Nuc. Sci. Eng., Vol. 69, pp. 411–429 (1979)Google Scholar
  9. 9.
    Prosperetti, A.; and Plesset, P.; Vapour-bubble growth in a superheated liquid, J. Fluid Mech., Vol. 85, Part 2, pp. 349–368 (1978)CrossRefADSGoogle Scholar
  10. 10.
    Frost, D.; Effects of ambient pressure on the instability of a liquid boiling explosively at the superheat limit, Ph.D. Thesis, Caltech, p. 95 (1985)Google Scholar
  11. 11.
    Anilkumar, A.V.; Experimental studies of high-speed dense dusty gases, Ph.D. Thesis, Caltech (1989)Google Scholar
  12. 12.
    Tepper, W.; Experimental investigation of the propagation of shock waves in bubbly liquidvapour-mixtures, Proc. 14th Int. Symp. on Shock Tubes and Waves, edited by R.D. Archer and B.E. Milton (1983)Google Scholar
  13. 13.
    Peterson, R.J.; Grewal, S.S.; and El-Wakil, M.M.; Investigations of liquid flashing and evaporation due to sudden depressurization, Int. Jour. Heat Mass Transfer, Vol. 27, No. 2, pp. 301–309 (1984)CrossRefGoogle Scholar
  14. 14.
    DuPont Corp., Freon fluorocarbons: properties and applications, Publication G-1Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1990

Authors and Affiliations

  • L. G. Hill
    • 1
  • B. Sturtevant
    • 1
  1. 1.Graduate Aeronautical LaboratoriesCalifornia Institute of TechnologyPasadenaUSA

Personalised recommendations