Study of Functioning of a Vortex Tube with a Two-phase Flow

Abstract

As a result of consideration of the phenomena occurring in the vortex tubes, it has been established that there are two forms of swirling dust-gas flow. The circumferential velocity profile in the zone of swirler and return flow is close to the quasi-solid type of rotation. In the peripheral zone, it is close to the quasi-potential type. It has been established by simulation that in the zone of quasi-solid rotation and subsequent transition to a quasi-solid flow, aggregation of particles takes place due to an intense collision of the dust particles drifting to the walls of the vortex tube. There is a 5 to 10 times increase in the determining particle size depending on the value of their specific surface area. In the zone of quasi-potential flow, the bulk of the solid dust particles is concentrated near the tube walls in a zone close to the boundary layer and the dust-free gas concentrates in a zone close to the axial flow. Taking into account the effect of uneven distribution of the braking temperature and consequently creation of a positive gradient of gas temperatures from the tube axis to the walls, thermodynamic and kinetic conditions arise for destruction of CO, NOx, SOx gas impurities (in the case of hot gas with a temperature above 673 K). Thus, when preparing a dusty gas stream from a process source before feeding it to the dust collector, the vortex tube creates conditions for complex purification of the gas stream from dust and gas impurities. Also, efficiency of dust removal in the main unit increases to 99.9 %. This will make it possible to lower the industrial negative impact on atmosphere and reduce threat of global consequences for future generations