Abstract
The centered expansion wave of a shock tube is utilized to expand and supersaturate a condensable vapor in small concentration in an inert carrier gas. The supersaturated state, located at the rear of the expansion wave, is preserved for a controlled period and then terminated by a recompressing shock wave. During the period of supersaturation, condensation nuclei are formed homogeneously. The nucleation rate is measured as a function of supersaturation by a Mie-light scattering technique. The method is tested using water and the results are compared with classical nucleation theory.
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Abbreviations
- a :
-
speed of sound
- d :
-
distance of observer from scattering particle
- D :
-
distance between observation station and virtual origin in the expansion fan of the shock tube
- Δ * :
-
increase of the free energy of the system for the formation of one droplet of critical size
- I :
-
intensity of scattered light
- I o :
-
average intensity of incident light illuminating droplet
- J :
-
nucleation rate
- k :
-
Boltzmann constant
- K :
-
preexponential factor in J = K exp (− ΔG */kT)
- M :
-
Mach number
- n :
-
index of refraction
- N :
-
number of droplets in scattering volume
- p :
-
pressure
- r :
-
radius of droplet
- r * :
-
radius of nucleus of critical size
- R :
-
universal gas constant
- S :
-
saturation ratio, S=yp/p ∞ (T)
- t :
-
time
- T :
-
temperature or relative scattered intensity
- r :
-
scattering volume
- \(\bar V\) :
-
molar volume
- gl:
-
distance upstream from virtual origin of expansion fan
- y :
-
mole fraction of condensable vapor in carrier
- γ:
-
gas ratio of specific heats
- λ:
-
wavelength of laser
- ϕ:
-
scattering angle
- σ:
-
surface tension
- 1:
-
driven side of shock tube, initial state
- 2:
-
state behind initial shock
- 3:
-
state at tail of expansion wave
- 4:
-
driver side of shock tube, initial state
- exp:
-
experimental
- n:
-
nucleation at observation station
- nc:
-
nucleation (corrected) along path of fluid element
- s:
-
at saturation, i.e. where the adiabatic expansion attains saturation of the vapor
- t:
-
mixing tank
- w:
-
water
- ∞:
-
flat surface equilibrium
References
Anderson, R. J.; Miller, R. C.; Kassner, J. L., Hagen, D. C. 1980: A study of homogeneous condensation-freezing nucleation of small water droplets in an expansion cloud chamber. J. Atmos. Sci. 37, 2509
Becker, R.; Döring, W. 1935: Kinetische Behandlung der Keimbildung in übersättigten Dämpfen. Ann. Phys. 24, 719
Kassner, J. L., Jr., Carstens, J. C.; Vietti, M. A.; Biermann, A. H., Yue, P. C. P.; Allen, L. B.; Eastburn, M. R.; Hoffman, D. D.; Noble, H. A., Packwood, D. L. 1968: Expansion cloud chamber technique for absolute Aitken nuclei counting. J. Rech. Atmos. 3, 45
Kotake, S.; Glass, I. I. 1981: Flows with nucleation and condensation. Prog. Aerosp. Sci. 19, 129
Lee, C. F. 1978: An experimental investigation of the critical supersaturation of five vapors in a Shock tube. Ph.D. Thesis, Yale Univ., New Haven, USA
Liepmann, H. W.; Roshko, A. 1975: Elements of Gasdynamics. New York: John Wiley & Sons, Inc.
Mirabel, P.; Katz, J. L. 1977: Condensation of a supersaturated vapor IV. The homogeneous nucleation of binary mixtures. J. Chem. Phys. 67, 1697
Peters, F. 1982: Homogeneous nucleation of ethanol and npropanol in a shock tube. J. Chem. Phys. 77, 4788
Van de Hulst, H. C. 1957: Light Scattering of Small Particles. New York: John Wiley & Sons, Inc.
Volmer, M. 1939: Kinetik der Phasenbildung. Leipzig: Steinkopff
Volmer, M.; Flood, H. 1934: Tröpfchenbildung in Dämpfen. Z. Phys. Chem. 170, 273
Volmer, M.; Weber, A. 1926: Keimbildung in übersättigten Dämpfen. Z. Phys. Chem. 119, 277
Wagner, P. E.; Stey, R. 1981: Homogeneous nucleation rates of water vapor measured in a two-piston expansion chamber. J. Phys. Chem. 85. 2694
Wegener, P.; Lundquist, G. 1951: Condensation of water vapor in the shock tube below 150 K. J. Appl. Phys. 22, 233
Wegener, P. P.; Wu, B. J. C. 1977: Gasdynamics and homogeneous nucleation. Adv. Colloid Interface Sci. 7, 325
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Peters, F. A new method to measure homogeneous nucleation rates in shock tubes. Experiments in Fluids 1, 143–148 (1983). https://doi.org/10.1007/BF00272013
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DOI: https://doi.org/10.1007/BF00272013