| Autor: |
van Dongen, M. E. H., Smolders, H. J., Braun, C. J. M., Snoeijs, C. A. M., Willems, J. F. H. |
| Zdroj: |
Applied Optics; April 1994, Vol. 33 Issue: 10 p1980-1988, 9p |
| Abstrakt: |
Two supplementary methods for time-dependent droplet sizing, both based on the spectral dependence of light extinction, are applied to an adiabatically expanding vapor in which droplets are formed as a result of heterogeneous condensation. First, by measuring the extinction coefficients at three different wavelengths, we obtain time-dependent values of the modal radius, the size variance, and the droplet number density, with a typical time resolution of 1 μs. The shape of the size-distribution function is investigated by a second method. Using a white-light source in combination with a spectrometer and a CCD array, we obtain the full visible light attenuation spectrum with a time resolution of 1.5 ms. By applying an inversion technique based on trial size distributions, we find that the zeroth-order log-normal distribution describes the fog adequately. Both methods yield the same droplet growth curves and droplet number densities. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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