The National Research Council of Canada, a pioneer in computational predictions of ice accretion, is making breakthroughs in predicting ice crystal formation on aircraft and engines.

In one recent business deal, Montreal-based Newmerical Technologies International licensed an innovative NRC-patented modeling technology that can predict the shape and structural details of ice accretions that can affect aircraft safety.

Developed and patented by NRC, this “morphogenetic” modeling technology can simulate the formation of rough and discontinuous ice structures, predict ice accretion density, and ice surface roughness. In addition, it can provide measures of the inherent stochastic variability of the ice accretion shape and structure, consistent with that observed in nature and in icing wind tunnel experiments. The morphogenetic model is the only numerical algorithm that inherently covers the prediction of all types of ice formation under changing atmospheric conditions, says Stewart Baillie, director of NRC’s flight research department.

The technology has potential applications for a wide variety of aircraft, including commercial airliners, business jets and general aviation.

NRC says its licensing agreement with Newmerical Technologies is but one example of how NRC helps the Canadian aerospace industry compete in the competitive world market, while also improving passenger safety.

In another example, as part of a joint research project with NASA, the FAA and Transport Canada, the NRC continues to advance the fundamental understanding of ice crystal accretion in the engine core. Boeing is also involved.

The latest National Research Council ice crystal research confirms that ice can accrete in an engine core under certain pressure and temperature conditions when the temperature is above freezing. It is now able to induce this phenomena in ice-capable wind tunnels.

Many jet engine power-loss events have been observed since 1990 at altitudes above 7,000 meters (23,000 ft.), usually considered to be the upper limit for the altitude at which water droplets can exist as liquid. These events, which have typically occurred in the anvil region of deep convective systems at tropical latitudes, have included engine rollback, flameout, stall, as well as damage to the low-pressure compressor from shed ice.

NRC has now confirmed the importance of ice crystal size to ice crystal accretion in the engine core.

This represents a significant step forward in the understanding of how ice builds up in aircraft engines under ice crystal conditions.

Regulators in North America and Europe will start certifying commercial turbojet engines against this type of ice buildup beginning in 2012, and current research data from NRC and its collaborators will inform these regulatory bodies.