"Transition to authentic turbulence in pipe flows” --Dr. Rory Cerbus

Internal Seminar: Rory Cerbus, Postdoctoral Scholar, Fluid Mechanics Unit (Chakraborty Unit)
 

"Transition to authentic turbulence in pipe flows” --Dr. Rory Cerbus

Abstract: As everyone knows who has opened a kitchen faucet, pipe flow at low flow velocities looks smooth and regular, but at higher flow velocities it looks jagged and irregular. The regular flow is called laminar, and the irregular flow is turbulence. Most flows in nature will transition from the laminar to the turbulent state with increase in flow velocity. Pipe flows, as observed by Osborne Reynolds over 130 years ago, transitions spontaneously and violently. As he watched a transitioning pipe flow he noticed some regions remained laminar, while other regions became irregular in an intermittent pattern. He called these confined spots of irregular flow, “flashes”, and they have been the subject of intense study ever since. Although they are irregular, they have certain properties which are very strange and different from what many call “fully turbulent” (really intense turbulence at large flow speeds). For example, the “flashes” can spontaneously die. They can also grow or split. And yet, I will present our recent experimental results on “flashes” and show that they possess many of the same statistical properties as “fully turbulent” flows.

Refreshments will be served afterwards. We hope to see you there!
 

Sincerely,
 

Internal Seminar Organizing Committee:

Marylka Yoe Uusisaari
Bianca Sieveritz
Rob Campbell
Margaret Mars-Brisbin
Lauren Dembeck
Maeva Techer
Jigyasa Arora
Yuka Suzuki