Barriers to the Transport of Diffusive Scalars in Compressible Flows

@article{Haller2020BarriersTT,
  title={Barriers to the Transport of Diffusive Scalars in Compressible Flows},
  author={George Haller and Daniel Karrasch and Florian Kogelbauer},
  journal={SIAM J. Appl. Dyn. Syst.},
  year={2020},
  volume={19},
  pages={85-123}
}
Our recent work identifies material surfaces in incompressible flows that extremize the transport of an arbitrary, weakly diffusive scalar field relative to neighboring surfaces. Such barriers and enhancers of transport can be located directly from the deterministic component of the velocity field without diffusive or stochastic simulations. Here we extend these results to compressible flows and to diffusive concentration fields affected by sources or sinks, as well as by spontaneous decay. We… 

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