With the right physics, it’s possible to blast a box of awesome circles across the solar system with pinpoint accuracy to penetrate a longitudinal corridor of distant worlds.
Fluids are indeed chaotic elements, but a new way of calculating their motion could make their flows more predictable.
Not only can scientists use it to improve our understanding of hydrodynamics, it could also make everything from weather forecasts to vehicle design more accurate.
Physicists from the Georgia Institute of Technology have shown that it is possible to identify moments when chaos reflects measurable patterns and to effectively find flashes of mathematically defined order.
“About a century ago, perturbation was defined statistically as a stochastic process,” says Georgia Tech physicist Roman Grigoriev. deterministic equation.
Turbulence is difficult to predict because of the way small eddies form in the fluid. When the object flows in a straight line in a smooth stream, its speed and trajectory can be easily predicted. If any path in the flow slows down, perhaps by being dragged along a less moving surface, the fluid will return to itself.
With each new current, a new surface is created that can generate new eddies. And just to make it more complicated, each vortex behaves at the whim of a range of factors, from pressure to viscosity, quickly adding up to a storm in a teacup that no computer can hope to track.
And up close, everything seems random. Go back a step and the statistics show that the overall process strictly follows the same old rules that govern all other moving matter in the universe.
“Turbulence can be thought of as a car following a series of paths,” says Grigoriev. follows.”
Like our common rails, turbulence can be described by numerical simulations or physical models. If you want reliable forecasts, like a train schedule that helps you run on time, sticking to a mathematical approach to chaos is the only way to go.
Unfortunately, all these numbers can add up quickly, making the calculations expensive.
To see if there was a way to simplify the estimates, the team created a tank with transparent walls and a liquid containing small fluorescent molecules. Directing the fluid between a pair of independently rotating cylinders and watching the glowing contents is like watching trains pass through the station in real time.
However, researchers really need to look up timelines first and see which ones are similar to what they found.
Doing so involves computational solutions to a set of equations that were developed nearly 200 years ago. By aligning the experiment with the mathematical results, the team can determine when certain perturbation patterns, called coherent structures, appear.
Although they appear regularly in moving fluids, the timing of coherent structures is unpredictable. In this particular setup, the coherent structures follow a quasi-periodic pattern of two frequencies, one rotating around the axis of flow symmetry and the other due to another set of shifts in the surrounding current.
While there is no simple set of equations that can describe chaos in all its forms, it does show the role that coherent structures can play in making it more predictable.
By extending this work, future research can make the “timelines” of perturbations more dynamic and explain them in more detail than statistical averages can provide.
“This could give us the ability to significantly improve the accuracy of weather forecasts, especially predicting extreme events like hurricanes,” Grigoriev said. For example, to reduce friction around cars to improve fuel efficiency, or to improve mass transit to help remove more carbon dioxide from the atmosphere in the emerging direct air capture industry.”
This research was published in PNAS.
Source: Science Alert
Source: Arabic RT
