Evaporation of a spherical liquid drop with varying radius as non-Markov random process

The article investigates the evaporation of a spherical liquid drop in an infinite medium and diffusion processes of evaporated vapor particles in the medium. This takes into account the fluctuations are always available particle flow across the border drops caused by random changes in temperature, pressure, etc. Furthermore it is believed that the drop due to evaporation of the particles varies slowly in size. An integral equation is got for the drop particle flux. Using the method of describing of non-Markov processes, determined by linear integral transforms, it is found the statistical characteristics of the investigated process. It is shown that the power spectral density of fluctuations of the vapor particles concentration in the drop surface is colored noise of complex form and has a maximum that depends on the radius of the drop.