Investigating microscale patchiness of motile microbes under turbulence in a simulated convective mixed layer
Fig 2
Dimensionless stability (Ψ) and swimming (Φ) number values for microbes at different depths within our IBM. Expected patchiness is greater when Ψ ≈ 1 and for large Φ.
(a) The stability number Ψ of simulated microbes varied through the Deep (light blue), Mid (yellow) and Shallow (red) depth regions of the flow. To contextualise our simulations with respect to real world flows, grey boxes illustrate the range of the stability number Ψ at expected values of ϵ and ν within a convective oceanic mixed layer (see S2 Text). The stability number Ψ of our microbes is broadly similar to that expected in such real world conditions. (b) The swimming number Φ of simulated microbes also varied through the Deep (light blue), Mid (yellow) and Shallow (red) depth regions of the flow. Here again, grey boxes illustrate the range of the swimming number Φ at expected values of ϵ and ν within a convective oceanic mixed layer convective turbulence (see again S2 Text). The swimming number of microbes in our IBM overlaps with realistic values, but was generally lower (see Discussion).