[BITList] World's biggest wind tunnel

[John Feltham]

Begin forwarded message:





Rare glimpse into world's biggest wind tunnel that blows gusts twelve times the speed of sound

-sent by Prabs

By Richard Hartley-parkinson
Last updated at 1:43 AM on 7th February 2011

Shrouded in total secrecy, massive wind tunnels that test the resistance of European aircraft have been opened up and photographed.

Journalists were offered the rare glimpse of the 24 metre diametre steel tubes at the National Centre for Aeropsace Research (Onera), where propellers, weighing over a tonne each, power the huge gusts of wind.

Despite their size the fans can get up to speeds of 230 revolutions every minute - nearly four a second - at the world's largest wind tunnel that tests aircraft to their limit.


A model A380 is suspended inside gigantic wind tunnels where speeds similar to 12 times the speed of wind can be simulated

The simulations last for just a matter of seconds, but the four tunnels in Modane allow manufactures and defence ministries to test hypersonic flight, sometimes exceeding 12 times the speed of sound.

The huge site was built out of sight with extreme precision after it was discovered during World War Two.

Jean-Paul Becla, test director at the site in Modane, eastern France, said: 'A French mission in 1945 discovered a tunnel being built in Austria by the Germans. It chose to take it apart and put it in France, aware that it was a major issue.

'The site, chosen for its air quality, also has the advantage of being close to dams producing enough energy for the wind tunnels, which alone consume one thousandth of France's electric capacity.


The massive propellers, weighing a tonne each, are 24 metres in diameter and can get up to speeds of 230 rotations a minute

Patrick Wagner, site director of Modane who last opened the doors to journalists in 2003, said: 'Thanks to them, the tests, close to real conditions, improve the quality of the aeroplanes so that they consume less fuel and improve their sound.'

The air friction over the wings of aircraft is helpful to manufacturers who want to improve the performance and noise levels, according to Denis Maugars, chief executive of the National Research Centre.

As he spoke he was stood in front of a prototype of a spacecraft that it is forbidden to photograph.

'Our main asset for customers is our confidentiality. One mistake and it would be over for us,' he added.


The site, in Modane, close to France's border with Italy, was chosen for its air quality because it has the advantage of being close to dams that produce enough energy for the wind tunnels

The facility is regularly monitored by the army and remains a place of crucial importance to the future research.

Mr Wagner continued: 'We are facing a reality where computers will not suffice to make such calculations and where large scale tests like those conducted in Modane remain paramount.

Mr Maugars remained tight-lipped about projects that Onera is currently working on adding: 'The turnaround in the U.S. position on the importance of wind tunnel tests confirmed our choice,' referring to the stimulus package of 600 million voted by Congress.

'We are very vigilant about what happens abroad and hold firm against the Chinese, who regularly ask us to cooperate.'


,___

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.bcn.mythic-beasts.com/pipermail/bitlist/attachments/20110215/86a36c7b/attachment.shtml