Osborne Reynolds - Definition and Overview

Osborne Reynolds (23 August, 1842 – 21 February, 1912) was an Irish engineer. He was born in Belfast, Ireland and died in Watchet in Somerset, England. He graduated from Cambridge University in 1867 after studying mathematics. In 1868 he became a professor of engineering in Manchester, and was only the second to hold this role in England. He retired in 1905.

Reynolds famously studied the conditions in which the flow of fluid in pipes transitioned from laminar to turbulent. From these experiments came the dimensionless Reynolds number for dynamic similarity - the ratio of inertial forces to viscous forces. In 1877 he was elected a fellow of the Royal Society, and in 1888 he won the Royal Medal.

Reynolds also proposed what is now known as 'Reynolds-averaging' of turbulent flows, where quantities such as velocity are expressed as the sum of mean and fluctuating components. Such averaging allows for 'bulk' description of turbulent flow, for example using the Reynolds-averaged_Navier-Stokes_equations.

A crater on Mars is named in his honor.

External link

• Short biography (http://www-gap.dcs.st-and.ac.uk/~history/Mathematicians/Reynolds.html)