Taylor dispersion

Summary

Taylor dispersion is the enhanced spreading of a solute along a pipe or channel. It comes from the combined action of a shear flow and diffusion across the flow. At long times the average concentration over a cross-section obeys an advection–diffusion equation. Its effective diffusivity can be far larger than the molecular one. The effect is named after G. I. Taylor, who analysed it for flow in a pipe. It matters in chromatography, in microfluidics and in the transport of substances in blood vessels and rivers.