Manchester Applied Mathematics and Numerical Analysis Seminars
Lecture Theatre OF/B9 Oddfellows Hall (Material Science)
The family of boundary-layer flows established by a differential rotation rate between a disk and a fluid at infinity in rigid-body rotation includes the Bödewadt, Ekman and von Karman boundary layers. Very few experimental studies have been performed on the Bödewadt boundary layer (i.e. a stationary disk with rigid-body rotation of the fluid sufficiently far above). This three-dimensional mean flow is unstable to disturbances at low Reynolds number. Moreover the net radial flow is inwards, i.e. in the direction of decreasing Reynolds number, and convectively unstable modes propagate inwards, which implies that obtaining a central region of laminar flow requires laminarization of the outer (in the higher Reynolds-number region) turbulent flow. For these reasons it is not a simple task to achieve a laminar region nor to make comparisons between theory and experiment for, say, values of the critical Reynolds number for linear instability. In this seminar I will describe experiments performed at the Mechanics Department of KTH, Stockholm.
For further info contact either Matthias Heil (email@example.com), Mark Muldoon (M.Muldoon@umist.ac.uk)or the seminar secretary (Tel. 0161 275 5800).