‘Scary’ experience twists research

Horia Hangan knows better than almost anyone that he shouldn’t have been there.

“It was scary,” Hangan said, recounting those moments in the driver’s seat of a small sedan on Feb. 20. “I saw this black rotational cloud and the funnel right in front of me, and I knew what it was. So, I stopped. But I couldn’t do anything,”

The principal investigator for WindEEE Dome, the world’s first hexagonal wind tunnel under construction at Western, was driving from Boulder, Col., to the University of Wyoming in Laramie, Wyo., where he was meeting colleagues at the Centre for Wind Energy. He was on a tight schedule, so Hangan chose to ignore the warnings about severe winds and highway closures.

When he left Boulder the weather was calm, which falsely built confidence in his ability to make it to his destination before the winds peaked. Signs posted along the route cautioned drivers of the danger, but Hangan persisted, not wanting to miss his evening appointment.

Once he crossed the state border into Wyoming, Hangan felt the air shift. The winds picked up and snow was drifting across the highway.

“The car starts wobbling and at a certain point, I see in front of me, essentially, a tornado cell,” he recalled. “There was basically no visibility, drifting snow. The highway was going straight through the storm system. It was a rotational tornado-like cell generated by shear winds, rather than by temperature differences.”

The area’s topography enhanced the wind system, a common occurrence at the base of the Rocky Mountains. It was the equivalent of an F1 tornado with 80 m.p.h. (129 km/h) winds, Hangan said.

“It is not tornado season, so they don’t call it a tornado,” he noted.

The one-way highway didn’t give him the option of turning back. “The moment I stopped,” he said, “I figured out the wind picks up the car even more.”

When Hangan got back on the road, he tracked the red lights of the vehicle in front of him through the storm. As he made his way toward Laramie, he saw several vehicles – much larger than his own – littering the side of the highway, cast aside by the windstorm.

“There was no escape. You either make it or ditch it,” he said.

Eventually Hangan arrived at his destination. The wind intensity continued for two days, keeping highways closed and residents stranded.

While this type of windstorm is common in the area during the change of seasons, he said, “the length of event was pretty unique. The winds were constant for three days in a row.”

Of course, Hangan has an advantage most people who experience such a weather event don’t – he has a lab dedicated to better understanding what happened.

In Wyoming, the winds were enhanced by topography. WindEEE Dome will allow researchers to reproduce topography at a larger scale to better understand how the two interact. WindEEE research collaborators at Western Engineering and the University of British Columbia are already examining the relationship between wind and trees, which will provide insight into the effectiveness of windbreaks along highways, among other applications.

“An event, like this, it opens your eyes,” he said. “It brings a human aspect to it – how humans react to those events.”

Hangan now has a flood of new research questions that go beyond structural and engineering design problems, such as the aerodynamics of vehicles and highway protection. He would also like to examine when a vehicle is most vulnerable in a windstorm – either driving in a lateral wind or remaining stationary.

Improving alerts to drivers in the area of such a weather event is another area for research consideration.

“There are a bunch of problems classical wind engineering doesn’t deal with … but they can have a huge impact in storms,” he says. “We will do things in WindEEE that appear very real, but we have to make sure we connect what we do in the lab with reality.”