Experimental study of ice accretion on S826 & S832 wind turbine blade profiles

To optimize the aerodynamic performance and reduce production losses of wind turbine operating in icing conditions, it is necessary to better understand the ice accretion physics along wind turbine blade. This paper describes a case study of ice accretion physics and its effects on aerodynamic performance of S826 and S832 airfoils for dry and wet ice conditions. Both these airfoils have different geometric characteristics and are suitable for horizontal axis wind turbine blade. Icing tunnel experiments are carried out at Cranfield University to understand and simulate the ice accretion on both profiles. Results show that difference in geometric characteristics of both airfoils affects the ice accretion and more complex ice shapes are observed in case of S832 profile compared to S826. Analysis show that ice thickness is higher in case of dry rime ice conditions as compared to wet ice, whereas more complex ice shapes are observed for wet ice conditions. Computational Fluid Dynamics (CFD) based numerical analysis are carried out to study the airflow and droplets behaviour and to estimate the aerodynamic performance of both clean and iced profiles. No numerical simulations of ice accretion are carried out. CFD analysis show a change in airflow behaviour for iced profiles which leads to a decrease in aerodynamic performance, when compared with the clean profiles. The change in aerodynamics performance is higher for S832 than S826 particularly for wet ice conditions.