Computation and applications of time dependent condensational aerosol growth /
A time dependent model of combative, nonlinear, nonisothermal, condensational growth kinetics of submicron particles is develop based on the Mt order couple phenomenological equations of mass and heat transfer. The mutual interaction between the vapor and temperature gelds in the vicinity of the low...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1999.
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| Subjects: | |
| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=733668121&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | A time dependent model of combative, nonlinear, nonisothermal, condensational growth kinetics of submicron particles is develop based on the Mt order couple phenomenological equations of mass and heat transfer. The mutual interaction between the vapor and temperature gelds in the vicinity of the lowing droplets is descry by Mt order erections to the standard mass and heat fluxes to the droplet. The time varying droplet surface temperature due to change of phase and the corresponding coupled change in the interface valor pressure are calculated iteratively throughout the droplet growth. A time dependent bulk parameter model is applied in order to calculate the simultaneous growth of a randomly distributed, initially polydisperse aerosol. The feedback effects of vapor depletion and latent heat release on the growth rate of the ensemble of particles is modeled through time dependent bulk parameters for the ambient vapor concentration and temperature. The effects of the chemical composition and curvature is included in determining the vapor pressure of the droplet aerosol. The droplet growth rate solutions are modified by transitional correction factors to apply in the free molecular and transition regimes. The nonlinear and fatback effects of combative condensation kinetics demonstrate increase variance of particle sizes due to growth contrary to traditional avowing of droplet spectrum. The model is applied to predict the activation and growth spectrum of cloud condensation nuclei in the initial stages of cloud condensation considering the random stochastic variability in the supersaturation at the cloud base. A Gaussian distribution whose mea is the measured time and space averaged cloud supersaturation is used to represent the viability of parcel supersaturation at the cloud bee. Broader widths are predicted by the model compare to calculations by the closed adiabatic parcel theory at a constant updraft. The activation spectrum at the cloud base is broader with lager droplets for low initial particle concentrations and narrower with smaller drops for higher particle concentration consistent with current observations of cloud microstructure. |
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| Item Description: | Vita. "Major Subject: Nuclear Engineering". |
| Physical Description: | x, 124 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilm Inc. |
| Bibliography: | Includes bibliographical references (leaves 95-102). |