The leaky-dielectric model is incorporated in the Finite Volume Method (FVM) code, OpenFOAM, to investigate the electrospray emission behavior of low to moderate conductivity liquids. This work extends FVM modeling to moderate conductivities by employing a new interface interpolation scheme that is devised in the Volume of Fluid (VOF) method to ensure charge conservation for accurate reproduction of charge accumulation and resulting meniscus shape in the cone-to-jet region and jet break-up. The FVM approach with the new interpolation scheme has been validated against experiments and scaling laws for heptane and tributyl phosphate (TBP) of low and moderate conductivity. Results agree well with experiments and scaling laws for droplet diameter and total current. The droplet diameter is shown to increase as the dimensionless flow rate increases or the electric Reynolds number decreases. Results are also consistent with parametric investigation of the meniscus shape and the maximum charge density for key operating conditions (flow rate and potential difference) and liquid properties (conductivity, surface tension, viscosity, and relative permittivity). These results show that the new interface interpolation scheme provides accurate results for a wide range of conductivities, fluid properties, and operating conditions. The results also provide valuable physical insights for varying liquid conductivity in the electrospray emission process. In particular, low dimensionless flow rate or high electric Reynolds number leads to the emergence of convex-outward menisci associated with a high charge density in the cone-to-jet region, resulting in high jetting velocity and high specific charge of emitted droplets.

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