Rotating-disk boundary-layer flow

Authors: Imayama, S.I., Alfredsson, P.H., Lingwood, R. J.
Document Type: Conference
Pubstate: Published
Journal: Svenska Mekanikdagar, Lund, Sweden, June 12-14, 2013
Year: 2013


Rotating-disk flow has been investigated not only as a simple model of cross-flow instability to compare with swept-wing flow but also for industrial flow applications with rotating configurations. About 28–32 stationary (in the rotating frame) convectively unstable cross-flow vortices are typically observed in the flow visualization 1, see as well as figure 1. However, the onset of transition is highly reproducible in various experimental facilities 2. Lingwood 3 found local absolute instability for a certain travelling disturbance above R = 507 which may have main responsible for the transition process, where Reynolds number R is defined as R = r ∗√(Ω ), where r is a local radius, Ω is a rotational speed, ν is a kinematic viscosity and ∗ denotes dimensional value. A main objective of this experimental study is to investigate to what extent the absolute instability is involved into laminar-turbulent transition of rotating-disk flow.