Back Manningvergelyking Afrikaans صيغة مانينغ Arabic Manningova rovnice Czech Fließformel German Fórmula de Manning Spanish معادله مانینگ Persian Formule de Manning-Strickler French Fórmula de Manning Galician משוואת מנינג HE Formula di Gauckler-Strickler Italian
The Manning formula or Manning's equation is an empirical formula estimating the average velocity of a liquid in an open channel flow (flowing in a conduit that does not completely enclose the liquid). However, this equation is also used for calculation of flow variables in case of flow in partially full conduits, as they also possess a free surface like that of open channel flow. All flow in so-called open channels is driven by gravity.
It was first presented by the French engineer Philippe Gaspard Gauckler in 1867,[1] and later re-developed by the Irish engineer Robert Manning in 1890.[2] Thus, the formula is also known in Europe as the Gauckler–Manning formula or Gauckler–Manning–Strickler formula (after Albert Strickler).
The Gauckler–Manning formula is used to estimate the average velocity of water flowing in an open channel in locations where it is not practical to construct a weir or flume to measure flow with greater accuracy. Manning's equation is also commonly used as part of a numerical step method, such as the standard step method, for delineating the free surface profile of water flowing in an open channel.[3]
- ^ Gauckler, Ph. (1867), Etudes Théoriques et Pratiques sur l'Ecoulement et le Mouvement des Eaux, vol. Tome 64, Paris, France: Comptes Rendues de l'Académie des Sciences, pp. 818–822
- ^ Manning, R. (1891). "On the flow of water in open channels and pipes". Transactions of the Institution of Civil Engineers of Ireland. 20: 161–207.
- ^ Chow (1959) pp. 262-267