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Home / Science / Scientists restored a devastating "freak wave" in the lab and they are strangely familiar

Scientists restored a devastating "freak wave" in the lab and they are strangely familiar



On the Draupner oil platform off the coast of Norway, workers would expect big waves to shake things up from time to time. But on New Year's Day 1995 at 3 pm a monster struck. It has made history.

At nearly 26 meters, this was the kind of wave you would expect once in a century. The really confusing part was that it came out of nowhere. Now the researchers finally have solid evidence of the forces involved in the formation of the wave.

A team of engineers from Oxford and Edinburgh Universities sent waves in a circular pool to create a perfect storm.

"The measurement of the Draupner wave in 1995 was a groundbreaking observation that initiated many years of research into the physics of freaker waves and shifted their reputation from mere folklore to a credible real-world phenomenon," says engineer Mark McAllister of Oxford University.

"By restoring the Draupner wave in the laboratory, we have come one step closer to understanding the possible mechanisms of this phenomenon."

Rogue waves like the ones Draupner hit are literally legendary. As long as sailors have migrated into the sea, there are reports of isolated water mountains.

Buoys have measured waves up to 1

9 meters high in the lonely expanse of the deepest oceans, while they are on ships of waves that are nearly 30 meters high, are known.

But rogues are characterized by their spontaneity more than by their size. In contrast to the types of waves that are whirled up by storms and currents, these waves emerge from the chaos of interfering wave patterns and strike without warning.

The 1995 Draupner Wave was a milestone; The first of its kind was recorded with scientific instruments and has been under investigation for two decades.

There are two theories that describe the physics responsible for rogues, but which of the best representations for Draupner was unclear. So the researchers built a miniature version of the monster wave under laboratory conditions to test which types of waves create something really impressive.

 Great wave in the laboratory Still photographs show the most successful reconstruction of the Draupner wave. (McAllister et al., Journal of Fluid Mechanics, 2019)

The team conducted their experiment in a 25 meter (82 foot) round test tank at the FloWave Ocean Energy Research Facility in the United Kingdom by. They swung from different angles to find out which ones formed into outstanding waves.

They discovered wave banks that could intersect at 120 degrees, forcing an occasional giant to emerge. Without this crossover, the environmental conditions have limited the maximum wave height.

You can check the movement of the waves in the following clip:

"Not just this laboratory The observation shed light on how the famous Draupner wave could have occurred and it also shows that Nature and importance of breaking waves when crossing the sea, "says Ton van den Bremer, senior researcher of the study from the University of Oxford.

The mini Rogue Wave reflects the rogue wave actually photographed on the open sea, which convinces the team that they are on the right track.

But for the researchers, it also looked unpleasantly like a classic depiction of famous Japanese artworks.

Even if you do not know much about the Japanese artist Katsushika Hokusai, you've probably seen his work. The Woodcut of 1830 The Great Wave off Kanagawa is one of the most famous depictions of a breaking wave in the world. It has become an iconic image on t-shirts, mugs and wall hangings.

It is impossible to say that Hokusai actually experienced or heard such rogue waves that they were described and thus created the final work of art based on these impressions.

In fact, it has been suggested that the artist represents a moment in Japanese history. when the nation was on the verge of Western culture. Breaking an isolated wave in the open sea would be the perfect metaphor for a changing Japan.

Aside from the intentions, the artwork still does the perfect job of illustrating the frightening nature of rogue waves as unpredictable, destructive forces of nature. 19659003] The Draupner oil platform was lucky. It was built to withstand waves larger than the 1995 New Year's Day, and suffered little damage.

But many other structures and ships were not so happy that stray incidents caused death and destruction.

Studies like This is a long way to highlight the conditions that make rogue waves more likely, and hopefully make the sea voyages much safer.

This research was published in the Journal of Fluid Mechanics .


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