Simulation of Icing on a Cascade of Stator Blades

Abstract

Investigations were conducted to examine ice accretion on a cascade of stator blades and its influence on the resulting aerodynamics. In particular, ice shapes and aerodynamic penalties were investigated on a stage 67A stator blade, which represents a part of a turbomachinery compressor stage. A steady Reynolds-averaged Navier-Stokes solver for the airflow was used with a Lagrangian continuous random walk for the droplet trajectory released upstream of the stator blade to predict impingement efficiencies. These results were coupled after finite icing intervals (ca. every 3 min) to update the ice shape around the stator blade using LEWICE. The overall methodology allowed the prediction of the impingement efficiency, the amount of ice accretion, and the adverse effects on the aerodynamic performance. Ice accretion is found to be significantly sensitive to droplet size, integration time, and temperature. However, relatively weak sensitivity was found with respect to the turbulence and angle of attack. Changes in the flowfield due to ice accretion can lead to boundary-layer separation, which causes a reduction in the flow turning angle and mass flow rate as well as an increase in the total pressure