At a recent FLUENT Users' Group Meeting, Dr. David Kohlman presented a short course on aircraft icing. The course covered the environmental conditions responsible for icing and a number of deicing and anti-icing systems in use.

Traditionally, aircraft icing was studied by performing experiments in an icing wind tunnel or by flying an aircraft in the wake of a tanker aircraft spraying water droplets. These methods are expensive and time consuming which lead researchers to computational modeling.

Using FLUENT's discrete phase model, researchers are able to track droplet trajectories and determine collection efficiency (the number of droplets which impact the surface) on the wing surface. The collection efficiency may be used in conjunction with NASA programs developed to predict the ice shape which forms on the wing over time. The ice shape is important because the shape of the wing can be significantly affected which leads to dramatic changes in its lift and drag properties.

One anti-icing method is to distribute hot bleed air from the engines through the wing to keep the wing surface above freezing temperatures. FLUENT has been used to model this type of anti-icing system.

Through computational modeling, it is hoped that aircraft icing can be controlled and that the number of accidents due to this hazard decrease.