Separated FlowsWakes and Cavities

Olivier Cadot, Equipe Dynamique des Fluides et Acoustique de l’Unité de Mécanique, ENSTA, Palaiseau.

OverviewShort serie of 4 lectures

Application fields : naval research, aerodynamics of salient bodies (cars, lorries… ), geophysical flows (island wakes)...

Streamlines that do not follow the solid body

attached flow

•Complex wake structure and dynamics

• Consequence on drag and lift

separated flow

Bluff body wakes at large Reynolds numbers

circular cylinder

Re=102.

Bluff body wakes at large Reynolds numbers

Square cylinder

Re=104.

Bluff body wakes at large Reynolds numbers

Car (real scale Re = 5 106)

Car, lorries, trains Re>106.

Car (scale 1/8)

Bluff body wakes at large Reynolds numbers

Island wakes

Re>108.

Bluff body wakes at large Reynolds numbers

airfoils

Re>106.

Vapor and gaz cavities in liquids at large Re

• Cavity size

• Local pressure, drag and lift

• Cavity dynamic

• Super-cavities, ventilated wake.

Cavitating blade

Cavitating plate wake

Super-cavitation

Lecture plan

• 12th december.

• 19th december.

• 9th january at ENSTA Palaiseau, fluid mechanics facilities

• 16th january at ENSTA Palaiseau, fluid mechanics facilities .

• Examination : to be defined.

absent from 4th feb to 13th may

• Generalities

• Separation in context of the B.L.T.

• 2D Bluff body flows

• Free streamline flow theory

• Cavitation

ENSTA Cavitation Tunnel

lecture room D105

meeting in front of the main entrance

The SOURCES /

Articles from <1970 + some recent reviews

Books :