Hydrodynamic Interactions Between Olfactory Appendages and Odor Plumes

摘要

The objective of this study was to elucidate ways in which the structure and the motions of olfactory antennae affect how they encounter the concentration distributions in odor plumes. First, detailed measurements, using a combination of laser-Doppler anemometry, laser-induced fluorescence, and planar laser-induced fluorescence were made to characterize the odor plumes for different flow conditions. A model lobster was then placed in the laboratory flume and we measured the odor concentration distribution around the olfactory appendage using high-speed video and laser-induced fluorescence techniques. We found that the plumes are characterized by long filamentous structures which produce concentration fluctuations of hundreds of Hertz. Analysis of the plume data shows that while the peak rms concentration occurs along the centerline of the plume (in the horizontal plane) the peak non-dimensionalized (by the local mean concentration) rms values lie at the edge of the plume. The presence of hairs (versus no hairs) on the lobster antennules greatly influences the duration of time that the odorant is in contact with the antennule during any flicking operation. Flicking has a substantial affect on the redistribution of the odorant on the antennule, and the flicking operation increases the concentration of odorant at the antennule.