Heat And Mass Transfer In Evaporating Turbulent Drop-laden Flow
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This work deals with the computational modelling of the mass transition of evaporating liquid drop-laden gas flows. In the present study the evaporation model due to Abramzon and Sirignano (1989) has been extended by introducing an additional transport equation for a newly defined quantity a, defined as the phase-interface surface fraction. This allows the change in the drop diameter to be quantified in terms of a probability density function. The source term in the equation describing the dynamics of the volumetric fraction of the dispersed phase αD is related to the evaporation time scale τΓ. Keywords: Euler/Euler approach, Euler/Lagrange approach, gas/liquid flow, evaporation model, heat and mass transfer, volume and surface fraction. 1 Introduction The dimensionless numbers characterizing the heat and mass exchange process are Nusselt numberNu and Sherwood number Sh. Several models (e.g. Renksizbulut and Yuen  and Park et al. ) are based on the correlation model of Ranz and Marshall  and have been developed to model the parameters. The evaporation rate model of Abramzon and Sirignano  considers additionally the latent heat flux of the evaporated liquid leaving the droplet. The correct capturing of the gas phase humidity requires the liquid vapor mass ratio Y , influenced by convective, conductive, turbulent and thermal diffusive effects, to be computed from an appropriate transport equation in addition to the equation governing the temperature field T . In an evaporating process the mass transfer rate on the drop surface depends on the drop size. The polydispersed spray consists of drops with different diameters.
Euler/Euler approach, Euler/Lagrange approach, gas/liquid flow, evaporation model, heat and mass transfer, volume and surface fraction