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Short presentations by participants
Short presentations by participants
Silas Alben (New York University)
Flow-body interactions in fish swimming
Lisa Fauci (Tulane University)
Spirochetes and spermatozoa: Fluid dynamic models of microorganism
motility
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, that undulate as a result of the action of thousands of molecular motors positioned along the flagellum. We will present mathematical and computational models that couple the internal force generating mechanisms of these microorganisms with external fluid mechanics. We will describe our methodology, which includes both the method of regularized Stokeslets and the immersed boundary method. We will discuss recent successes as well as challenges associated with these models.
Raymond Goldstein (University of Arizona)
Lecture
Raymond Goldstein (University of Arizona)
Lecture
Raymond Goldstein (University of Arizona)
Lecture
Raymond Goldstein (University of Arizona)
Lecture
Raymond Goldstein (University of Arizona)
Lecture
Raymond Goldstein (University of Arizona)
Lecture
Raymond Goldstein (University of Arizona)
Lecture: Overview
Raymond Goldstein (University of Arizona)
Lecture
Raymond Goldstein (University of Arizona)
Lecture
Anette (Peko) Hosoi (Massachusetts Institute of Technology)
Optimizing Locomotion
Thomas Powers (Brown University)
Mechanics of Flagella
Michael J. Shelley (New York University)
Lecture
Michael J. Shelley (New York University)
Lecture
Michael J. Shelley (New York University)
Lecture
Michael J. Shelley (New York University)
Lecture
Michael J. Shelley (New York University)
Lecture
Michael J. Shelley (New York University)
Lecture
Michael J. Shelley (New York University)
Lecture
Michael J. Shelley (New York University)
Introduction to Biophysical Fluid Dynamics
Michael J. Shelley (New York University)
Lecture
Michael J. Shelley (New York University)
Lecture
Idan Tuval (University of Arizona)
Right Hand-Left Hand: On the Origins of Asymmetry in Vertebrates
Jane Wang (Cornell University)
Falling Paper and Dragonfly Flight
Charles Wolgemuth (University of Connecticut Health Center)
Two-phase Fluids and the Mechanics of Crawling Cells
Jun Zhang (New York University)
Unidirectional Forward Flight of a Flapping Wing
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 influence from the solid boundaries nearby. Through dimensional analysis, we found that there are two dimensionless parameters well describe this intriguing problem that deals with this fluid-solid interaction. The first one is the dynamical aspect ratio that combines four length scales, including the wing geometry and the flapping amplitude. The second parameter, the Strouhal number, relates the vertical flapping speed and its resultant forward flight speed. Overall, we emphasize the robustness of the thrust-generating mechanisms determining the forward flight speed of a flapping wing, as observed in our experiments.
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