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What is the WindEEE facility?

It鈥檚 a wind research centre that is very different to conventional wind tunnels. For a start, the . In the lower part of the chamber we have 60 fans on one wall and eight directional fans on each of the other five walls, and in the upper chamber are six huge fans. All are individually computer controlled.

What can you do with a set-up like that?

It鈥檚 very versatile. We can create straight flows, but also rotating ones, to simulate tornadoes and downbursts. To picture a downburst, imagine turning on a tap: the water falls fast and when it hits the sink it spreads out. A similar thing happens with air and it is very dangerous to aircraft.

Tell me about your 鈥渢ornado in a bottle鈥�.

We can create a . A tornado is a combination of rotation and suction. By angling the airflow from the fans around the lower chamber we control the rotation of a tornado vortex, and we create the suction by running the six huge fans in reverse. The beauty of our tornado is that we can move it along the ground at 2 metres per second.

Have you tried standing in that swirl?

Yes, but the whole flow is scaled down 鈥� the size, the velocity. So if I stand in the vortex it鈥檚 very, very gusty and hard to keep my balance, but it won鈥檛 pick me up. With the straight flow, wind speed gets up to about 40 m/s. In tornado mode, 30 m/s.

How can you tell where the wind is going?

The simplest way is using smoke. We can also put helium-filled soap bubbles in the flow, which are neutrally buoyant, and take pictures to see the flow鈥檚 behaviour. We have sensor arrays too.

What鈥檚 been done with WindEEE so far?

We became operational in October, and have so far tested wind loading on full-scale roof-mounted solar panels. We鈥檙e also looking at the effects of a tornado on buildings: we aim to find out if tornado wind loading should be included in building codes.

What other projects are you running?

We鈥檙e partnering with the European Union as part of a project called Horizon 2020. Turbines in a wind farm can interact with each other, affecting the airflow between them. We simulate that flow and then model different wind turbines, types of rotor control and so on. It鈥檚 about extracting as much power as you can from wind turbines.

What do you most enjoy working on?

I鈥檝e chased real tornadoes, so our tornado is my favourite. But the facility is versatile. For example, we鈥檝e looked at the effect of downwashes 鈥� akin to downbursts 鈥� on a remote-controlled airplane.

Have you flown the plane into the tornado?

[Laughs] No. The thing about tornadoes is that you can see them, so pilots don鈥檛 fly into them. Downbursts can be invisible. But we have the plane, so maybe one day we鈥檒l fly it into the tornado and let you know what happens.

This article appeared in print under the headline 鈥淭he tornado in a bottle鈥�