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With a little bit of imagination - the gentle breeze, the sky-blue ceiling and sea-blue base - Auckland University's wind tunnel can become the Mediterranean.
On occasions it probably has for Emirates Team New Zealand's sail designers and trimmers who have spent endless hours in the facility trying to create perfect sails for the fickle conditions off the coast of Valencia.
Since sails and rigs are expected to be the main areas of development in this year's America's Cup, the university's wind tunnel - the first of its kind in the world - has been a crucial part of Team New Zealand's preparation.
The tunnel allows designers to test ideas and establish which sails make the boat go faster, the differences between designs, which sails perform best in which conditions and each sail's stability.
It operates by simulating the wind as experienced by a yacht moving through the water. Two giant fans blow through twisting vanes, which resemble vertical blinds, on to a scale-model yacht on a turntable.
Team New Zealand have spent a lot of time at the Auckland facility - on average they test 10 new sail designs every six weeks - but BMW Oracle, Alinghi and South Africa's Shosholoza have also used it, as have a number of round-the-world teams.
David Le Pelley is the manager of the wind tunnel and works for Oracle in research and development. He said the tunnel would remain a useful tool for cup syndicates for some time yet, with teams continuing to develop sails through the regatta.
"A lot of the challengers, if they have got any hidden weapons in their sail inventory, they are only going to bring them out fairly late in the game. We can very quickly imitate and build a sail if we need to, test it in the wind tunnel and we can have a full-scale one built in a couple of weeks."
Sail technology was the area with the biggest potential.
"With Valencia being so different to Auckland, it has been a long road for people to develop sails for there. They are still on a steep learning curve.
"From this far in, I'd say there is still a lot of mileage there and there could be some interesting sail designs."
Although some sail innovations are obvious - for example, the square top mainsail - developments in the spinnakers, asymmetrical and downwind sails are not as easy to spot. But Le Pelley said there were significant differences among the teams.
"The twist profiles [the view vertically up the sail's edge] tend to set up a bit differently because of the flow in Valencia being thermally driven. It is not a very sustained breeze. It occurs very rapidly. When you get that you end up with a very high twist in the flow or a high shear, that means you have to design the sail with more twist. The sail sizing is different as well. The air density is a lot different in Valencia to a lot of places where the challengers have been testing. It is very hot, it is very low density air."
The wind tunnel is part of the university's Yacht and Wind Research Unit, set up in 1987 by Professor Peter Jackson, a performance analyst for the New Zealand Challenge. The unit was initially funded by Sir Michael Fay.
This year 21 graduates are spread among eight syndicates - the highest representation of any one university.
The unit has led the way in many concepts, including being the first to apply Computational Fluid Dynamics (CFD) to the flow around spinnakers. CFD is a computer program which breaks down wind flow into tiny cells allowing more in-depth analysis.
In 1994, the unit, in conjunction with Team New Zealand, built the first wind tunnel with twisted flow, where the breeze changes angle with height so the correct apparent wind onto the sails can be simulated.
The unit's director, Professor David Flay, said there were three known copies of the twisted flow tunnel around the world - one in Milan, one in Germany and one in Valencia at Chris Dickson's Oracle Racing.
"It has been said that we won the cup in 1995 because of superior aerodynamics," Flay said. "I am really proud that we had something to do with that."
Despite the unit's leading-edge nature, Flay said finances had been a "bit of a struggle".
He said it was difficult to get government grants and convince the boating industry to fund research. With more funding Flay believes the university could become "the world's leading centre of yacht research".
