The quickest route to turbulence
For decades, researchers in thermodynamics and fluid mechanics have debated exactly how fast waves and eddies, that is, turbulence can arise in different flows. KTH researchers have now come up with an answer.
A group of researchers at the Research Centre Linné Flow Centre at KTH with Luca Brandt in charge has designed the fastest route to turbulence in a so-called laminar flow. The findings are so important that it has resulted in a published article in the prestigious scientific journal Physical Review Letters.
"We have made calculations to find out the minimum interference necessary to create turbulence," says Luca Brandt, a senior lecturer and researcher in fluid mechanics at KTH.
Fluid mechanics is the study and influence of flows in water, air and other media. The newly attained knowledge is a first step towards avoiding turbulence for example in pipes. Turbulence leads to the flow of water moving slower, and that more force is required for water or air to pass through the pipes.
But there are also times when you want turbulence, and this is where Luca Brandt and his colleagues' research comes in handy.
"In a combustion chamber in an engine, you need the turbulence in order to obtain the best mix of air and fuel. "It is slightly ahead of itself, but the research findings may provide a basis for a better understanding of this phenomenon," says Luca Brandt.
The research team consists not only of Luca Brandt, but also of the student Antonios Monokrousos and Professor Dan Henningson. The research is a collaboration with Professor Alessandro Bottaro from Università di Genova.
For more information, contact Luca Brandt at 08 - 790 68 70 or luca@mech.kth.se.
Pete Larsson