Vapor Pressure and Equilibrium Radius of Dielectric Spherical Droplet Under Electrostatic Field

doi:10.12141/j.issn.1000-565X.220007

Abstract

Abstract:

The condensation or evaporation of droplet is a phase change process, which is not only an efficient heat and mass transfer process, but also has a close relation with the change of the environmental climate. Experimental results show that the electrostatic field has a big influence on the formation of droplet, and it is an effective way to enhance heat and mass transfer and it’s also related to the formation of lightning and rain. Based on the phase equilibrium theory, this paper derived the mathematical expressions of pressure difference, vapor pressure and equilibrium radius of spherical dielectric droplet under electrostatic field by using the thermodynamic equations with the effects of electric field. By means of numerical calculations, it analyzed the formation process of droplet with these mathematical expressions. The results show that the pressure difference, vapor pressure and equilibrium radius of dielectric droplet under electrostatic field are increased compared with those without electric field. The increase of vapor pressure and equilibrium radius will accelerate the evaporation process of droplet, so the electrostatic field can promote the evaporation of droplet. This conclusion is consistent with the experiments and can provide reference for related theoretical researches and engineering applications.

Key words: electrostatic field, dielectric spherical droplet, difference of internal and external pressure, vapor pressure, equilibrium radius

CLC Number:

TB131

HAN Guangze, CHEN Junyan . Vapor Pressure and Equilibrium Radius of Dielectric Spherical Droplet Under Electrostatic Field[J]. Journal of South China University of Technology(Natural Science Edition), 2023, 51(2): 131-136.

Figures/Tables 4

References 23

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