HR: 16:45h
AN: OS54A-04    [Abstracts]
TI: Fluid Dynamic Constraints on Morphology and Propulsion of Medusae at Low Reynolds Numbers
AU: * Dabiri, J O
EM: jodabiri@caltech.edu
AF: California Institute of Technology, Graduate Aeronautical Laboratories and Bioengineering, Mail Code 138-78, 1200 E. California Blvd., Pasadena, CA 91125,
AU: Colin, S P
EM: scolin@rwu.edu
AF: Roger Williams University, Environmental Sciences, Bristol, RI 02809,
AU: Costello, J H
EM: costello@providence.edu
AF: Providence College, Biology, Providence, RI 02918,
AB: A recently developed mathematical model for physical constraints on the size and morphology of medusae was extended to include viscous effects that dominate at low Reynolds numbers. This fluid dynamic regime is experienced by all medusae during development and also by some adults. The lack of inertia in the flow field generated by medusae at low Reynolds numbers limits the vortex formation that is ubiquitous at higher Reynolds numbers. This consequently leads to the need for large oblate rowing medusae to use different propulsive solutions during their juvenile stages of development. Specifically, empirical observations of scyphomedusae (e.g., Aurelia sp.) and hydromedusae (e.g., Aequorea victoria and Obelia sp.) indicate distinct wake structures and swimming kinematics for each body type that exists during different stages of development. These differences can be explained by the extended mathematical model. In addition, ontogenetic changes can be visualized as trajectories within a plot of the new model.
DE: 4203 Analytical modeling and laboratory experiments
DE: 4800 OCEANOGRAPHY: BIOLOGICAL AND CHEMICAL (0460)
SC: Ocean Sciences [OS]
MN: 2007 Fall Meeting