Effect of Characteristic Phenomena and Temperature on Super-Cooled Large Droplet Icing on NACA0012 Airfoil and Axial Fan Blade

Abstract

Icing simulations involving super-cooled large droplets (SLDs) on a NACA0012 airfoil and a commercial axial fan were performed considering the characteristic behavior of SLD icing (i.e., splash-bounce, deformation, and breakup). The simulations were performed considering weak coupling between flow field and droplet motion. The flow field was computed using the Eulerian method, wherein the droplet motion was simulated via the Lagrangian method. To represent the ice shape, an extended Messinger model was used for thermodynamic computation. The ice shape and collection efficiency of the NACA0012 airfoil derived using the icing simulation exhibited a reasonable agreement with the existing experimental data. The icing simulation results for the axial fan, in terms of distribution of ice on the blade and its influence on the flow field, indicated that flow separation occurred, and the mass flow rate of the flow passage decreased. Moreover, the splash and bounce phenomena considerably influenced the icing process; however, the effect of the deformation and breakup phenomena was negligibly small. In terms of the effect of the SLDs on the icing phenomena, it was noted that, with the decrease in the SLD temperature (from −5 °C to −15 °C), the number of adhering SLDs increased, whereas the number of splashing and bouncing SLDs decreased.

Keywords

• icing simulation
• super-cooled droplet
• large droplet
• NACA0012 airfoil
• numerical simulation