In the work, a model of explosive boiling of a single droplet was proposed, which is based on the classical nucleation theory. A criterion is proposed for estimation the droplet’s lifetime. Calculations were made for droplets of liquid oxygen in saturated vapor. Analysis is made for influence of the initial temperature and droplet size on its lifetime.
There are several installations with shock tubes in the world, in which a shock wave in air propagates at a speed close to the second cosmic one. Such velocities are achieved by supplying of high energy (~ 1 MJ) to the pushing gas in the high-pressure chamber.
In the experiment, the length of the detonation wave is usually determined by the duration of the luminescence of the OH radical, which corresponds to the zone of intense heat release. It is believed that the length of this zone is of the order of the longitudinal size of the detonation cell. In theory, the distance from the shock front of the wave to the Chapman -Jouguet point, in which the relative velocity of the gas is equal to the local speed of sound, is taken as the detonation thickness. The question arises about the possibility of introducing a coefficient of proportionality between these quantities, which would facilitate the comparison of experimental results and the theory of stationary detonation waves. This paper compares the experimental and calculated data on the length of detonation waves in mixtures of oxyhydrogen gas (2H2 + O2) with nitrogen. It is shown that the introduction of the coefficient of proportionality between the length of the detonation wave and the zone of intense heat generation is impractical (see figure below).
In this work, the simulation of the formation process of condensation aerosol in atmospheric air is carried out. The influence of the initial supersaturation ratio and dustiness content on the formation mechanism and macroscopic characteristics of the aerosol is investigated.
An approach that makes it possible to assess the need to take into account / neglect the process of homogeneous nucleation on the flow of vapor formed near the interface as a result of evaporation is presented. It is shown that estimations require information about the value of the surface tension coefficient of the critical size droplets. The influence of the homogeneous nucleation process on the evaporation of various substances: water, ethanol, and methanol is considered. The results show that for water, consideration of the process of homogeneous nucleation is necessary only for supersaturation ratio greater than 20, in contrast to the evaporation of methanol, when homogeneous nucleation must be taken into account at any supersaturation ratio Keywords: homogeneous nucleation, evaporation, supersaturation degree.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.