Computational investigation of multi-phase flow effects on the performance of the steam turbine exhaust hood

摘要

In this research work, a computational modeling of multi-phase flow through an asymmetric exhaust hood is presented. The three-dimensional Navier–Stokes equations along with the standard k - ɛ turbulent model and the Eulerian–Eulerian multi-phase equations were solved. The coupling of the last stage turbine blades and the exhaust hood has been carried out using the actuator disc model, which is less computationally demanding. The finite volume-based commercial computational fluid dynamics solver, ANSYS FLUENT, is used for the present numerical simulations. The effects of wetness on the flow structure and the pressure recovery capacity of a steam turbine exhaust hood have been investigated. One of the salient findings is that the pressure recovery capacity of a steam turbine exhaust hood enhances due to wetness effects. Wetness-induced turbulence damping is noted to be playing a crucial role in the enhancement of pressure recovery capacity of an exhaust hood.