The Calculation of Turbulent Multiphase Swirl Flows of a Viscous Heat-Conducting Gas with Volume Heat Release

Abstract

A boundary-value problem is calculated, which describes an axisymmetric swirl turbulent motion of a viscous heat-conducting gas and dispersed phase, including the processes of condensation of water vapor on liquid particles. A model is constructed for the dispersed phase, which takes into account the variation of water vapor concentration and particle size because of condensation or evaporation. The results of numerical investigations demonstrate that the centrifugal force causes the particles, which are initially located in the vicinity of the vortex axis, to rapidly collect in a narrow ring expanding downstream, where the intensive condensation of steam and corresponding heat release occur. It is found that, even in the case of low values of water vapor concentration c v ≤ 0.02 in the vortex core and very low values of the volume density of particles φ ≈ 2.5 ×10−8, the interphase heat transfer leads to significant changes of enthalpy and longitudinal component of gas velocity in the vortex core, while the circumferential component of velocity varies little. With low initial and spatially constant concentrations of liquid particles φ 0 ≤ 10−7, the effect of interphase heat transfer decreases somewhat simultaneously with the increase in the initial size of particles of the dispersed phase. However, in the case of moderate initial concentrations of particles 2 × 10−7 ≤ φ0 ≤ ≤2.5×10−6, the effect of heat transfer increases with the size of liquid particles.