Transient deformation and evaporation of droplets at intermediate Reynolds numbers

Abstract The early life histories of isolated n -heptane droplets injected into 1000 K air at 1 and 10 atm with initial Reynolds and Weber numbers of 100 and 2, respectively, are reported. A numerical model is used to predict the transient droplet shape, and the velocity, pressure, temperature and concentration fields in both phases. Initially spherical droplets show strongly damped oscillations at frequencies within 25% of the theoretical natural frequency of Lamb (1932). Circulation within the droplets is responsible for the observed strong damping and promotes the formation of prolate shapes for surfactant-free droplets. The computed heat and mass transfer rates are well predicted by existing quasi-steady correlations.

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