Classical flows

No Abstract

The locomotion of most fish and birds is realized by flapping wings or
fins transverse to the direction of travel. Here, we study experimentally
the dynamics of a wing that is flapped up and down but is free to move in
the horizontal direction. In this table-top prototype experiment, we show
that flapping flight occurs abruptly at a critical flapping frequency as a
symmetry-breaking bifurcation. We then investigate the separate effects of
the flapping frequency, the flapping amplitude, the wing geometry and the

The observed swimming behavior of a motile microorganism is the result
of a complex interplay between mechanisms of internal force generation,
the passive elastic properties of its structure, and a surrounding
viscous fluid. In this talk, we will focus on two very different types
of microorganisms: the spirochetes, which are a type of bacteria
characterized by an efficient mode of motility that allows them to
screw through viscous fluids and mucosal surfaces, and spermatozoa,