Взаимное влияние гидродинамических условий и фазовых переходов при кипении многокомпонентных вязких жидкостей

Abstract

The paper presents results on the intensity of heat and mass transfer during boiling of viscous liquids in a heated channel on the example of distillation of vegetable oil miscella. For the first time, local characteristics of heat transfer along the channel length were obtained for miscella containing linoleic sunflower oil. The values of the heat transfer coefficients are 100–250 W/m2·K. The mechanism of mass and energy transfer in the active working zone of the heated channel is described. The choice of the channel length with a diameter of 30 mm depending on the input mass concentration of vegetable oil in the misсella is justified: up to 60–70% no more than 1500–2000 mm, above 60–70% up to 4000–6000 mm. An experimental study of the formation in miscella of an oil-rich layer near heated surface is carried out. We think the thickness may be 0.3–0.4 microns. Dependences are obtained and a simple formula for calculating the thickness of this layer is proposed. The relationship between the hydrodynamic environment and the intensity of heat exchange along the length of the channel is established. The best mode is the bubble mode of the two-phase flow.