Numerical Study on Smoke Plume for Natural Draft Cooling Tower with Flue Gas Injection

Abstract

The new exhaust mode of natural draft cooling towers (NDCT) with flue gas injection is investigated. The three-dimensional model for NDCT with flue gas injection and the boundary conditions are established via the Gambit 2.3. The cross-section of drift eliminator is set the velocity entrance for thermo-hygro air (velocity-inlet). The flue entrance is set admission velocity (velocity-inlet), the exit of NDCT with flue gas injection is set free gas export (outflow), and the emission of net flue gas to the cooling tower is a source of buoyant jets. The N-S equations are solved with the standard k- turbulence model by the Fluent 6.3. The improved NDCT with flue gas injection avoids air disturbance low-pressure zone compared with the conventional NDCT with flue gas injection. The corrosion of NDCT with flue gas injection in throat is reduced because net flue gas is wrapped in thermo-hygro air. Temperature gradient of net flue gas was distinct, the high-temperature zone is concentrated, and the uplifting performance is improved.