ASME-Landmark:Icing Research Tunnel, NASA Lewis Research Center

Wind tunnels have been a part of aviation research since the days of Wilbur and Orville Wright. The Icing Research Tunnel (IRT) at the NASA Lewis Research Center was designed and built in 1944 by a group of engineers with wind tunnel design experience at NACA's Langley and Ames Laboratories. Although at least two icing tunnels existed prior to the IRT (at Massachusetts Institute of Technology and B.F. Goodrich), they were much smaller, as the technology to create a larger icing wind tunnel that could operate year round simply did not exist in the early 1940s. The IRT designers and contractors had to create new systems.

The IRT is a closed-loop, refrigerated wind tunnel with a 6x9 foot test section. It can generate airspeeds from 25 to over 400 miles per hour. It is similar to other subsonic wind tunnels in that a wing or other aircraft component placed in the test section can be subjected to various airspeeds. From its inception, however, the IRT had several unique features. For example, to simulate the aircraft icing environment, several additions were made to the basic subsonic wind tunnel design: a heat exchanger and a refrigeration plant to achieve the desired air temperatures and a spray system to generate a cloud of microscopic droplets of unfrozen water. The IRT is thus capable of duplicating the icing conditions (liquid water content, droplet size, and air temperature) that aircraft could encounter.

The IRT has played a substantial role in developing, testing, and certifying methods to prevent ice buildup on gas-turbine-powered aircraft and today remains the world's largest refrigerated icing tunnel. See ASME website for more information