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Suggested reading for preparation

Vorticity

• Brøns, M., Thompson, M.C., Leweke, T. & Hourigan, K., Vorticity generation and conservation for two-dimensional interfaces and boundaries, Journal of Fluid Mechanics, 758, 63-93, 2014.
• Lundgren, T. & Koumoutsakos, P., On the generation of vorticity at a free surface, Journal of Fluid Mechanics, 382, pp. 351-366, 1999.
• Morton, B. R., The generation and decay of vorticity, Geophysical & Astrophysical Fluid Dynamics, 28:3, 277 - 308, 1984.

Swirling Flows

• Brøns, M., Shen, W. Z., Sørensen, J. N. & Zhu, W. J., The influence of imperfections on the flow structure of steady vortex breakdown bubbles, Journal of Fluid Mechanics, 578, 453–466, 2007.
• Escudier, M., Vortex breakdown: Observations and explanations, Prog. Aerosp. Sci. 25, 189–229,1988.

Bluff Body Flows

• Johnson, T.A. & Patel, V.C., Flow past a sphere up to a Reynolds number of 300, Journal of Fluid Mechanics, 378, 19-70, 1999.
• Rao, A., Leontini, J., Thompson, M.C., Sheridan, J. & Hourigan, K., A review of rotating cylinder wake transitions, Journal of Fluid and Structures, 53, 2 - 14, 2015.

Flow-Induced Vibration of Bluff Bodies

• Bearman, P.W., Vortex shedding from oscillating bluff bodies, Annu. Rev. Fluid Mech., 16, 195-222, 1984.
• Williamson, C.H.K. & Govardhan, R., Vortex-induced vibrations, Annu. Rev. Fluid Mech., 36, 413-55, 2004.

Slides from Professor Hourigan's lectures

Lecture 1: Vorticity Generation I: Introduction and Key Concepts
Lecture 2: Vorticity Generation II: Free surfaces
Lecture 7: Swirling flow Instabilities: Pipes and Open Jets
Lecture 8: Bluff Body Wakes I: Introduction
Lecture 9: Bluff Body Wakes II: Transitions for Other Bluff Body Geometries
Lecture 10: Bluff Body Wakes III: Effects of Body Rotation
Lecture 11: Vehicle Aerodynamics
Lecture 12: Fluid-Structure Interactions I: Cyllinders
Lecture 13: Fluid-Structure Interactions II: Spheres and Cubes
Lecture 14: Fluid-Structure Interactions III: Controls
Lecture 17: Concluding Lecture

Slides from Professor Leweke's lectures

Lecture 3: Vortex Filaments

This lecture deals with flow configurations in which the vorticity distribution can be described as a system of one-dimensional lines, representing thin vortex filaments whose internal vortex core structure is neglected. The evolution of these filaments through self- and mutually induced velocities is discussed and illustrated for generic configurations, such as vortex rings and helical vortices.

Literature
Wu, J.-Z., Ma, H.-Y., Zhou, M.-D. 2006 Vorticity and vorticity dynamics. Springer. Chapters 3.2 and 8.2.

Lecture 4: Long- and Short-Wave Instabilities

Two instability mechanisms occurring in systems of concentrated vortices are presented. One involves displacement perturbations of the vortices, with wavelengths that are large compared to the size of their cores; it can be analysed using a filament approach. A second mechanism involves internal perturbations of the vortex cores, with wavelengths scaling on the core size, resulting from deformations of the cores due to curvature, torsion or the strain induced by neighbouring vortices. Examples involving vortex pairs and helical vortices are shown.

Literature
Leweke, T., Le Dizès, S., Williamson, C. H. K. 2016 Dynamics and instabilities of vortex pairs. Annual Review of Fluid Mechanics 48, 507-541

Slides from Professor Sørensen's lectures

Rotor-Aerodynamics-2019

Slides from Professor Brøns' lectures

Lecture 5: Vortex definitions and bifurcations of vortical structures Part 1 --- Streamlines and vortex breakdown

Full version with animations (28MB)
Small version without animations (8MB)

Lecture 6: Vortex definitions and bifurcations of vortical structures Part 2 --- Vorticity and the Q-criterion

Full version with animations (68MB)
Small version without animations (6MB)

BACKGROUND LITERATURE

Introduction to topological fluid dynamics

Vortex breakdown

Critical points of vorticity

The Q-criterion