抄録
A numerical model is developed to characterize erosion
caused by water droplets impinging against rotor blades at the first
stage of an axial flow compressor. Analyses assume a gas turbine
operating with an inlet fogging system. The change in the water
droplet size attributable to break-up and evaporation during flight
is considered. Numerical calculations are executed using a
commercial code in a two-dimensional computational domain
including an inlet guide vane, rotor, and stator.
The calculated erosion depth shows good agreement with
that obtained from empirical correlation in the case without a
break-up model. Results show that the break-up occurs over a
certain rotor speed, leading to marked reduction of the erosion
depth. The choice of the droplet critical Weber number determines
the rotor velocity which maximizes the erosion depth. Secondary
droplets discharged from the trailing edge of IGV (Inlet Guide
Vane) affect erosion more than primary droplets, although their
mass flow is smaller.
