Polarizability affecting water vapour condensation and ice glaciation

Abstract

The main purpose of this research is the study of the effect of modified newlinepolarizability in the nucleation rate of water vapor condensation and ice newlineglaciation in presence of external electric field. Due to this modification newlinethe nucleation rate and equilibrium concentration of critically sized nuclei newlineare increased. At the same time it will produce smaller critical nuclei which newlinerequire less free energy of formation. Thus in electric field induced newlinenucleation process, the super saturation ratio required would be very small newline(about less than 1%) whereas in Homogeneous nucleation process super newlinesaturation required is several percent. newlineThe present research work has been divided into following chapters. newline1. Introduction. newline2. The effect of external electric field on the nucleation of water vapor newlinecondensation and ice glaciation. newline3. The effect of modified polarizability in the nucleation rate of water newlinevapor condensation and ice glaciation in presence of external newlineelectric field. newline4. The nucleation rate and the equilibrium concentration in the newlineelectric field induced homogeneous nucleation. newline5. Study of electrical conductivity in the thunder storms under some newlinemeteorological conditions. newline In the following thesis we have shown the effect of electric newlinefield in the nucleation phenomenon by studying the nucleation rate, newlineequilibrium concentration, electrical conductivity and the relaxation time. newlineii newlineWe have discussed the effect of external electric field on the nucleation of newlinewater vapour condensation and ice glaciation by considering the variation newlineof density and surface free energy with temperature. Due the presence of newlineexternal electric field the nucleation process is much enhanced in water newlinecondensation and ice glaciations. We also modified the value of newlinepolarizability of water by taking into account electronic and ionic newlinecontribution to the polarizability. As water is highly polarizable medium, newlineso it plays an important role in inducing the electric dipole moment on newlinewater vapour molecule. We studied about the enhancement in