Photo credit: Wired.com
Article contributed by Steve Burns
Back on Wednesday we showed you the video of LMR’s 1,800rwhp Texas Mile C6 undergoing testing in the GM wind tunnel. In addition to watching some of the aero evaluations going on, the wind tunnel staff led us on a tour of their immense facility. We’ll take a detailed look at the GM wind tunnel after the break.
The GM wind tunnel is the largest automotive wind tunnel in the world. Work on the facility began in 1977 and it officially opened for business in 1980. In addition to testing cars, the GM aero team has evaluated racecars, skiers, cyclists and even boat keels. Currently the team is working 24 hours per day Monday through Friday.
Air in the tunnel travels in a rectangular path approximately 988ft long. The 43ft diameter fan with 6 Sitka Spruce Laminated blades is located on the opposite side of the actual testing area and moves the air. A 4,500hp DC electric motor powers the massive fan. The maximum air speed than can be generated is 138mph. That translates to 270rpm of the big wooden blades. At that speed, the tips of the blades are moving at 415mph! As part of our tour we were able to stand in the evaluation area as a 30mph wind was generated. One of neat features of the lab is an underground tunnel so design concepts and prototype cars can be moved without the need to go outside.
The volume of air in the lab is 57,000 cubic meters or about 75 tons of air being moved by the fan. The acoustically treated walls are constructed from 20,000 cubic yards of concrete. Temperature in the tunnel is regulated at a comfy 72 degrees F.
The actual scale of this test lab is hard to describe. You really can’t fully understand its immensity until you’re standing underneath the giant fan and you realize just how big that thing is. The lab staff has a sincere pride in their work that definitely showed during our visit. Click here to read more about the GM wind tunnel.
We weren’t permitted to take photos during the tour, but below are a few pictures showing the testing conducted with Late Model Racecraft’s 231 mph Texas Mile Corvette.