A model describing the vaporization of hydrocarbon droplets at high-pressure and temperature in non-uniform flow fields has been developed. This model is used to investigate the effect of ambient conditions similar to those found in diesel engines on droplet secondary breakup as characterized by a Weber number criterion. The droplet vaporization rate is calculated using an extended film model and the spherically symmetric energy equation is solved to obtain the evolution of the radial temperature distribution in the droplet. The high-pressure phase equilibrium at the droplet surface is evaluated by equating the fugacity of each species in each phase, as obtained from a Peng-Robinson equation of state. Furthermore, an advanced, composition-dependent surface tension model is implemented. Various background flows are then used, via one-way coupling, to investigate the effect of parameters such as ambient pressure and droplet initial diameter on droplet history and its propensity to breakup.
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