Evaporation of freely suspended single droplets: experimental, theoretical and computational simulations Holyst, R; Litniewski, M [Institute of Physical Chemistry of the Polish Academy of Sciences Kasprzaka 44/52, 01-224 Warsaw (Poland)]; Jakubczyk, D; Kolwas, K; Kolwas, M; Kowalski, K; Migacz, S; Palesa, S; Zientara, M [Institute of Physics of the Polish Academy of Sciences al. Lotnikow 32/46, 02-668 Warsaw (Poland)] 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; AIR; ARGON; CORRECTIONS; DENSITY; DROPLETS; EFFICIENCY; ENTHALPY; EQUATIONS; EQUILIBRIUM; EVAPORATION; EXCEPTIONS; INTERFACES; MASS; NITROGEN; SIMULATION; THERMAL CONDUCTIVITY; TRANSPIRATION; VAPOR PRESSURE; VAPORS; WATER Evaporation is ubiquitous in nature. This process influences the climate, the formation of clouds, transpiration in plants, the survival of arctic organisms, the efficiency of car engines, the structure of dried materials and many other phenomena. Recent experiments discovered two novel mechanisms accompanying evaporation: temperature discontinuity at the liquid-vapour interface during evaporation and equilibration of pressures in the whole system during evaporation. None of these effects has been predicted previously by existing theories despite the fact that after 130 years of investigation the theory of evaporation was believed to be mature. These two effects call for reanalysis of existing experimental data and such is the goal of this review. In this article we analyse the experimental and the computational simulation data on the droplet evaporation of several different systems: water into its own vapour, water into the air, diethylene glycol into nitrogen and argon into its own vapour. We show that the temperature discontinuity at the liquid-vapour interface discovered by Fang and Ward (1999 Phys. Rev. E 59 417-28) is a rule rather than an exception. We show in computer simulations for a single-component system (argon) that this discontinuity is due to the constraint of momentum/pressure equilibrium during evaporation. For high vapour pressure the temperature is continuous across the liquid-vapour interface, while for small vapour pressures the temperature is discontinuous. The temperature jump at the interface is inversely proportional to the vapour density close to the interface. We have also found that all analysed data are described by the following equation: da/dt = P{sub 1}/(a + P{sub 2}), where a is the radius of the evaporating droplet, t is time and P{sub 1} and P{sub 2} are two parameters. P{sub 1} = -{lambda}{Delta}T/(q{sub eff}{rho}{sub L}), where {lambda} is the thermal conductivity coefficient in the vapour at the interface, {Delta}T is the temperature difference between the liquid droplet and the vapour far from the interface, q{sub eff} is the enthalpy of evaporation per unit mass and {rho}{sub L} is the liquid density. The P{sub 2} parameter is the kinetic correction proportional to the evaporation coefficient. P{sub 2} = 0 only in the absence of temperature discontinuity at the interface. We discuss various models and problems in the determination of the evaporation coefficient and discuss evaporation scenarios in the case of single- and multi-component systems. (review article) Available from http://dx.doi.org/10.1088/0034-4885/76/3/034601 United Kingdom 2013-03-15 English Journal Article Journal Name: Reports on Progress in Physics; Journal Volume: 76; Journal Issue: 3; Other Information: Country of input: International Atomic Energy Agency (IAEA) Medium: X; Size: [19 page(s)] https://doi.org/10.1088/0034-4885/76/3/034601 [] 3 76 Journal ID: ISSN 0034-4885; CODEN: RPPHAG; TRN: GB13P5173114358 INIS 2013-12-02 22159926