Adhémar Jean Claude Barré de Saint-Venant

Adhemar Jean Claude Barré de Saint- Venant ( born August 23, 1797 in Villiers -en- Bière, Seine- et- Marne, † 6 January 1886 in St Ouen, Loir -et -Cher ) was a French engineer, mathematician and physicist.

Saint- Venant studied at the École Polytechnique from 1813 to 1816. Afterwards he worked until 1845 as an engineer, first by the Office for explosives manufacture (Service de Poudre et salpêtre ), then as a civil engineer for the highway department. To 1839, he attended lectures at the College de France in addition, among others, Joseph Liouville. He taught as a successor of Gaspard Gustave de Coriolis mathematics at the École des Ponts et Chaussées in Paris.

He worked mainly in the field of mechanics, elasticity, plasticity theory, hydrostatics and hydrodynamics. In France he was in his time one of the leading authorities in mechanics. Saint -Venant in 1843 published a correct derivation of the Navier -Stokes equations, two years before George Gabriel Stokes did this. He also extended Navier's theory of beam deflection ( 1864), dealt with the twist elastic cylinder and examined non-stationary flows in open channels. He published a French translation of the elasticity theory of Alfred Clebsch.

He also led in France a calculus with vectors. Because he published this in 1845, a year after Hermann Grassmann, but claimed he used since the 1830s to have, it was a priority dispute.

According to him, the principle of St. Venant and the St -Venant element is named.

In 1868 he became a member of the Académie des sciences in the section mechanics as successor to Jean -Victor Poncelet.