DOI: 10.1615/ICHMT.2012.ProcSevIntSympTurbHeatTransfPal
ISBN Print: 978-1-56700-302-4
ISSN: 2377-2816
Modeling of flow patterns and heat transfer in gas-droplets turbulent flow downstream of a pipe sudden expansion
Краткое описание
The two-fluid Eulerian model is used to describe the macroscopic characteristics of two phases downstream of a pipe sudden expansion. Gas phase turbulence is modeled with the use of the elliptic blending Reynolds stress model of Fadai-Ghotbi et al. (2008). Kinetic stresses, temperature fluctuations, and turbulent heat flux of the dispersed phase are predicted by Zaichik’s model (1999). The Lagrangian approach is used for comparative analysis. The presence of fine dispersed droplets in the flow attenuates gas phase turbulence (up to 25 % in the axis zone). In the wall area concentration of liquid droplets is much lower than in the axial region of the pipe due to droplets evaporation. Heat transfer in the gas-droplets separated flow increased (more than twice in comparison with the single-phase air flow). Intensification of heat transfer is observed both in the recirculation zone and flow development region in case of fine particles.