SUPERSONIC WIND TUNNEL

Press, Volume LXXXV, Issue 25997, 28 December 1949, Page 4

SUPERSONIC WIND TUNNEL

STUDENT ENGINEER’S WORK "The Press” Special Service AUCKLAND, December 27.

The first supersonic' wind tunnel in New Zealand has been made by a Chinese honours student, Mr George Lowe, at the Ardmore School of Engineering. Although the working section of the tunnel between perspex panels is only 7 inches high, 1J inches wide and about a foot long, in this space air speeds of up to 1000 miles an hour will eventually be produced. Already speeds so great as to produce deafening screams, as the air rushes past even streamlined bodies, can be built up and many of the effects recorded.

There are many uses to which the tunnel can be put, and it will become an important part of the school’s equipment. It may be useful in future research into high-speed wing sections, ram jets, guided missiles, turbine parts and other machinery required to travel at extreme speeds. However, the project is primarily part' of the education of the student. Professor T. D. J. Leech, professor of engineering. at the college, is an enthusiast for this type of work, and is, always ready to help. Six times faster than any wind tunnel previously constructed in the Dominion, the Ardmore model is operated by compressed air which ’draws behind it through the working section a stream of air from outside. Accurate means of measuring the pressures simultaneously from as many as 36 parts of the tunnel are provided, and the forces on the model under test can be measured by a balance. A feature of speeds near that of sound is-that shock waves are set up around the model. These can be photographed with special devices, giving further information from the point of view of design. Provision of. sufficient compressed air is a major problem with such tunnels and this one exhausts its supply in about 1J minutes at each running. However, this is ample time to make measurements and observations.