Скачать с ютуб Vortex-Induced Vibration of Soft Corals for Improved Food Capture - SICB talk в хорошем качестве

Vortex-Induced Vibration of Soft Corals for Improved Food Capture - SICB talk

Sea plume Antillogorgia bipinnata is a soft coral species endemic to the Caribbean Sea, which forms arborescent colonies. On the sea floor, a whole colony of A. bipinnata sways back and forth at the low frequency of surface wave action, while its branches exhibit a peculiar motion vibrating at high frequency transverse to the flow. In this presentation, we investigate the nature of these unreported high frequency vibrations and hypothesise on their biological implication with regards to food interception. We use computational fluid dynamics to simulate the particle interception of fixed cylinders and spring-mounted cylinders. We find that vibrating cylinders can capture up to 40% more particles than fixed ones when the frequency of the vortices shed in the wake of the cylinder matches with the natural frequency of the spring mounted cylinder. Whereas engineers have developed numerous inventions to prevent chimney stacks, risers, and other structures from vibrating due to vortex shedding; our results indicate that soft corals potentially benefit from this same phenomenon. Vortex-induced vibrations allow coral to sweep more water and possibly capture more food particles. Our theoretical results open the door for field and lab experiments for validation, and they provide another example of how natural structures differ from engineer-made ones. Presentation page at SICB: https://sicbannualmeeting.pathable.co... Learn more by reading Mouad's papers Boudina, M., Gosselin, F.P., Étienne, S. “Vortex-induced vibrations: a soft coral feeding strategy?” Journal of Fluid Mechanics, 2021, 916, A50. https://doi.org/10.1017/jfm.2021.252 https://arxiv.org/abs/2009.11764 Boudina, M., Gosselin, F.P., Étienne, S. “Direct interception or inertial impaction? A theoretical derivation of the efficiency power law for a simple and practical definition of capture modes” Physics of Fluids, 2020, 32, 123603 https://doi.org/10.1063/5.0030891 https://arxiv.org/abs/2011.06359v1