Large-Eddy Simulation of an Iced Swept Wing: A Perspective on the Aerodynamic Effect of Triggering Resolved Turbulence

Analyzing iced wing aerodynamics is important for ensuring aircraft safety. However, simulating iced configurations accurately and efficiently can be challenging due to the complex geometries and flow topologies involved. To investigate these challenges, wall-modeled large-eddy simulation of a swept wing with leading-edge ice buildup is performed using an unstructured Voronoi mesh paradigm and compared to experimental results. The study focuses on an 8.9% scale model of the CRM65 swept wing, a 65% scale version of the Common Research Model (CRM) geometry, featuring both high-fidelity and smooth leading-edge ice shapes at a Mach number of 0.18 and a Reynolds number per mean aerodynamic chord of 1.6 × 106. For the high-fidelity ice shape, good agreement with the experiment is obtained. For the smooth ice shape, incorporating roughness effects to trigger resolved turbulence near the leading edge results in an approximate factor of 30 reduction in computational cost for similar accuracy compared to simulating the smooth ice without roughness, using a simple equivalent sand-grain roughness estimate to mimic experimental grit roughness values. Furthermore, comparable accuracy is achieved at similar mesh resolutions for the high-fidelity ice and smooth ice with roughness. Finally, simulations of the tripped wing without ice are used to quantify the predicted aerodynamic degradation due to icing across an angle of attack sweep.