Modeling the dielectric strength variation of supercritical fluids driven by cluster formation near critical point

2020 
Density fluctuation driven by cluster formation causes drastic changes in the dielectric breakdown characteristics of supercritical fluids that cannot be described solely based on the conventional Townsend’s gas discharge theory and Paschen’s law. In this study, we model the dielectric breakdown characteristics of supercritical CO2 as a function of pressure based on the electron scattering cross section data of CO2 clusters that vary in size as a function of temperature and pressure around the critical point. The electron scattering cross section data of CO2 clusters are derived from those of gaseous CO2. We solve the Boltzmann equation based on the electron scattering cross section data to obtain critical electrical fields of various cluster sizes as a function of pressure. To validate our model, we compare the modeled breakdown voltage with the experimental breakdown measurements of supercritical CO2, which show close agreement.
    • Correction
    • Source
    • Cite
    • Save
    • Machine Reading By IdeaReader
    20
    References
    3
    Citations
    NaN
    KQI
    []