Study on Behavior of Breakup and Radial Migration of Droplets in a 5-stage Compressor

摘要

As an economical and effective means, water injection technology is currently used to improve the gas turbine power and efficiency. Due to the relatively long residence time of water droplets in the multistage compressor, the droplets may have a large amount of migration along the radial direction in the strong centrifugal force while they will also encounter considerable breakup because of aerodynamic shear stress and impacting onto blade surface. Numerical simulation was carried out to study motion and breakup of water droplets via Eulerian-Lagrangian multiphase flow model through a 5-stage subsonic axial compressor. Simulation results show that only very small droplets can follow the gas flow well. Droplets above 30 microns in diameter will eventually become smaller because of continuously impacting and breakup. It shows also that for large droplets radial migrations along the flow direction increase obviously.