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Вихревые трубы по эффективности уступают детандерам, но обладают рядом неоспоримых преимуществ, таких как компактность, надежность, многофункциональность. Несмотря на эти достоинства, существует совсем немного примеров эффективного применения вихревых аппаратов в криогенике. В работе рассмотрены проблемы, сопутствующие созданию вихревых охладителей, предназначенных для установок получения неона и гелия. Переход к низким температурам всегда сопровождается миниатюризацией газодинамических аппаратов. В то же время большинство рекомендаций по проектированию вихревой техники относится к высокорасходным устройствам, которые питаются сжатым воздухом при температуре окружающей среды. По этой причине известные геометрические соотношения не всегда применимы при создании криогенных вихревых установок с малыми диаметрами камеры энергоразделения. Экспериментальным путем изучено влияние масштабного фактора в интервале диаметров меньше 10 мм. Показаны преимущества ступенчатого включения низкотемпературных вихревых труб в схемах сепараторов редких газов. Обосновано использование технологического перепада давлений для питания вихревых криогенераторов.

A vortex tube is a Thermo-fluidic device, which generates cold and hot streams from a single injection of pressurized gas. Without any moving parts or chemical reaction within the tube, the interesting phenomenon of energy separation results only from fluid dynamic effects.The main part of a typical counter-flow vortex tube is a straight tube with a tangential injection, through which compressed gas is injected into the tube. There are two exits, located at different ends of a counter-flow vortex tube, or at the same end for a uni-flow vortex tube. A control plug is positioned inside the tube away from the injection point, which has a smaller dimension than the inner diameter of the tube, and this allows the gas to escape from the small gap between the control plug and the tube. The cold exit is located in the central part of the tube at the same end of the injection, while the hot exit is the gap between the plug and the tube.When the compressed gas is injected into the tube tangentially at a high velocity, two streams with different temperatures will be generated and exhausted from the two exits of the tube. This phenomenon of temperature separation in a vortex tube is known as the Ranque effect.Several explanations for the energy separation in a vortex tube have been proposed since its invention. However, due to the complex internal flow, the nature of the energy separation in the vortex tube, is still unclear. The proposed hypotheses can only be used to explain part of the phenomenon and they do not cover all the aspects of the temperature separation in the vortex tube. Therefore, to date, there has not been a well-accepted explanation for the thermal separation, and the flow behaviour inside the vortex tube remains unclear.This thesis presents fundamental investigations on the Ranque-Hilsch Vortex Exergy density analysis in the air-operated vortex tube was performed in this study and offered solid support for the proposed hypothesis. The analysis from this study, as well as the data from other studies, show a slightly decreased peripheral iii exergy density in the rear part of the tube, which defines the dominant contribution to the temperature rise from the stagnation and mixture due to multi-circulation.The dramatically reduced exergy density in the front part of the tube, together with an estimation of the temperature drop based on the forced vortex assumption, indicate that the pressure gradient in the front part of the tube is the primary factor contributing to the temperature drop.Based on the proposed hypothesis, discussion of various geometrical effects, such as cold mass flow ratio, tube length, tube diameter and inlet nozzle, on the tube performance has been undertaken. A good agreement between the theoretical and experimental results demonstrates the validity of the proposed hypothesis for the temperature separation occurring within a vortex tube.As a result of the study presented, a novel explanation for the temperature separation phenomenon inside a vortex tube can be forwarded, and can...