nominal linear flow, \(F\)

in chromatography
https://doi.org/10.1351/goldbook.N04177
The volumetric flowrate of the mobile phase divided by the area of the cross section of the column (cm min-1) i.e. the linear flowrate in a part of the column not containing packing.
Source:
Orange Book, 2nd ed., p. 102 (http://media.iupac.org/publications/analytical_compendium/)