The effect of downstream turbulent region on the spiral vortex structures of a rotating-disk flow

K. Lee, Y. Nishio, S. Izawa, Y. Fukunishi

Research output: Contribution to journalArticlepeer-review

3 Citations (Scopus)


Direct numerical simulations are carried out to investigate the role of the turbulent region in a self-sustaining system with a spiral vortex structure in the threedimensional boundary layer over a rotating disk by solving the full Navier-Stokes equations. Two computational domains with two different azimuthal sizes, 2π/68 and 2p=32, are used to deal with different initially dominant wavenumbers. An artificial disturbance is introduced by short-duration strong suction and blowing on the disk surface. After the flow field reaches a steady state, a turbulent region forms downstream of Re=640. The turbulent region is then removed using two methods: A sponge region, and application of a slip condition at the wall. In both cases, the turbulent region disappears, leaving the spiral vortex structure upstream unaffected. The results suggest that the downstream turbulent region is not related to the velocity fluctuations that grow by the global instability. In addition, when the area where the slip condition is applied is changed from Re > 630 to Re > 610, the velocity fluctuations decay. The results indicate that the vibration source of the velocity fluctuations which grow by the global instability is located between Re=611 and Re=630.

Original languageEnglish
Pages (from-to)274-296
Number of pages23
JournalJournal of Fluid Mechanics
Publication statusPublished - 2018 Jun 10


  • Boundary layer stability
  • rotating flows
  • transition to turbulence

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering


Dive into the research topics of 'The effect of downstream turbulent region on the spiral vortex structures of a rotating-disk flow'. Together they form a unique fingerprint.

Cite this