Cross Flow Effects on Glaze Ice Roughness Formation

Abstract The present study examines the impact of large–scale cross flow on the creation of ice roughness ele-ments on the leading edge of a swept wing underglaze icing conditions. A three–dimensional triple–deck structure is developed to describe the local in-teraction of a 3D air boundary layer with ice sheetsand liquid films. A linear stability analysis is pre-sented here. It is found that, as the sweep angle in-creases, the local icing instabilities enhance and themost linearly unstable modes are strictly three di-mensional. Nomenclature T m bulk freezing temperature, 273 o K for water sl solid–liquid surface tension lv liquid–vapor surface tension airfoil leading–edge nose radius H sl latent heat of freezing per unit mass of ice H lv latent heat of evaporation per unit mass of water densityc p specific heat k thermal conductivity thermal diffusivity dynamic viscosity m density ratio, = 1 – ( l / s )LWC liquid water content of impinging droplets (s) local collection efficiency sum of the principal curvatures of the interfaceU ambient airspeedT