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arXiv · 2104.06884

Revisiting d2-law for the evaporation of dilute droplets

Federico Dalla Barba·Jietuo Wang·Francesco Picano
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Abstract

In a wide range of applications, the estimate of droplet evaporation time is based on the classical d2-law, which, assuming a fast mixing and fixed environmental properties, states that the droplet surface decreases linearly with time at a determined rate. However, in many cases the predicted evaporation rate is overestimated. In this Letter, we propose a revision of the d2-law capable to accurately determine droplet evaporation rate in dilute conditions by a proper estimate of the asymptotic droplet properties. Besides a discussion of the main assumptions, we tested the proposed model against data from direct numerical simulations finding an excellent agreement for predicted droplet evaporation time in dilute turbulent jet-sprays.

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Federico Dalla Barba, Jietuo Wang, Francesco Picano. 2021-04-14. Revisiting d2-law for the evaporation of dilute droplets. https://doi.org/10.1063/5.0051078

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