Influence of surfactants on the formation of droplets of liquid from surface of film during kerosene vaporization in tank launcher

Abstract

The method of increasing the efficiency of evaporation of kerosene based on convective heat transfer in closed volumes and the introduction of a surfactant is developed. The method is relevant for many technological processes including: production of the launch vehicle (LV) with liquid rocket engines (LRE) in the shops of the manufacturer (drying fuel tanks after a technological operations associated with filling their technological fluids for washing, calibration, hydraulic testing, etc.); operation of the LV after shutting off of the LRE to ensure explosion safety of fuel tanks, extraction of unused energy resources in liquid fuel
residues in LV tanks. The results of an experimental study of the effect of surfactants on the thermophysical parameters of liquid kerosene on the determination of the coefficient of surface tension, viscosity with allowance for the introduced surfactants for various degrees of concentration are presented. It is recommended for surfactants based on polydimethylsiloxane for its possible use as an additive in kerosene. There are obtained experimental data on the effect of a surfactant based on polydimethylsiloxane on the surface tension of kerosene with various mass concentrations of surfactants. The application of surfactants to cryogenic fuels (for example, to liquid oxygen) is difficult, in view of the absence of surfactants active at such low temperatures. Theoretical estimates of the effect of surfactants on the intensity of droplet entrainment from a free surface are considered. It has been established that the introduction of a surfactant with a mass content of 0,2 % reduces the critical droplet breakdown rate by 18–22 %.