Icing of aerodynamic surfaces: modelling the shape of large ice growths

Abstract

Abstract.  Statement  of  the  problem.  Numerical  simulation  of  aircraft  icing  processes  during  the  flight  in  adverse meteorological conditions is a pressing issue in ensuring flight safety. The data on the simulated shapes of large ice build-ups, which, in turn, depend on the flight conditions, can be used to assess the degree of negative influence of icing on the aircraft. Research methodology. For the numerical simulation of the icing processes of the aircraftaerodynamic surfaces software and methodological support  were  developed.  When  describing  the  external  air-droplet  flow  and  moisture  precipitation  on  the  streamlined  surface,  a model of interpenetrating media was used; when describing the process of ice growing, the surface control volumes method based on the  equations  of  continuity  and  energy  conservation  was  used.  Results.  The  main  shapes  of  large  ice  growths  on NACA 0012 profile,  streamlined  with  a  two-dimensional  two-phase  viscous  compressible  flow,  taking  into  account  the  surface roughness and the interaction of the air flow and supercooled drops were reproduced. Conclusions. The physical  features of the icing process, leading to the formation of horn-like shapes of ice growths, were analyzed. The characteristic forms of ice build-ups in dry, wet and mixed icing modes were obtained. There is good agreement the obtained results with known experimental data. Studies of  the  effect  of  flight  and  meteorological  parameters  on  the  shape  of  ice  buildup  were  carried  out.  The  possibility  of  using  the developed research tool to determine the most “dangerous”, in terms of the degree of influence of icing on the aircraft, the range of parameters was illustrated.