Mass Transfer Performance of a Marine Zooplankton Olfactometer

By adopting different methods to the inlet of a zooplankton olfactometer, the current study investigates the effect of the energy of chemical flow on the Gnathiid isopod crustaceans predicted behavior. These are mobile external parasites of fishes that have a significant impact on the health of their hosts. They rely at least in part on olfactory cues to find the host fish. To better understand host-finding dynamics in these parasites, a study was conducted with the simulations as a blueprint for developing a 3-dimensional test apparatus similar to what has been used for studying olfactory orientation in insects. The simulated olfactometer has four legs, each leg forming an inlet where fluids are introduced into the flow domain. There is one outlet at the center of the device. A mixture of water and chemicals is presented by applying a multi-component system. The shear and chemical concentration distribution were conducted to see how fluid physics plays a role in creating a chemical landscape. Computational results show distinct regions separated by high chemical concentration gradients when introducing chemicals from one leg. Changing the fluid inflow from one common inlet to three inlets shows that the chemical distribution exhibits steeper gradients than the typical inlet case, depicting that the gradual chemical concentrations can drive the animal toward the target faster. The best behavior that gives higher chemical gradients is obtained through the study when using three sub-inlets and Schmidt number between 3 and 10.