Title: interstitial velocity
Long Title: IUPAC Gold Book - interstitial velocity
DOI: 10.1351/goldbook.I03121
Status: current

Definition
The linear velocity of the mobile phase inside a packed column calculated as the average over the entire cross section. This quantity can, under idealized conditions, be calculated from the equation: \[u=\frac{F}{\varepsilon_{\rm{I}}}\] where \(F\) is the nominal linear flow and \(\varepsilon_{\rm{I}}\) the interstitial fraction

Related Terms
- interstitial fraction: https://goldbook.iupac.org//terms/view/I03120
- mobile phase: https://goldbook.iupac.org//terms/view/M03952
- nominal linear flow: https://goldbook.iupac.org//terms/view/N04177

Source
- Orange Book, 2nd ed., p. 102 (https://media.iupac.org/publications/analytical_compendium/)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/I03121/html
- json: https://goldbook.iupac.org/terms/view/I03121/json
- xml: https://goldbook.iupac.org/terms/view/I03121/xml

Citation: Citation: 'interstitial velocity' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.I03121
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Accessed: 2026-05-18T12:52:05+00:00