Robert Stirling - Biography

Clergyman and inventor, born in Perth, Perth and Kinross, E Scotland, UK. He studied for the ministry at the universities of Glasgow and Edinburgh, was ordained in the Church of Scotland (1816), and was minister of Galston, East Ayrshire (1837–78). In the same year he patented a hot-air engine operating on what became known as the Stirling cycle, in which the working fluid (air) is heated externally. His engines were built from 1818 to 1922, by which time they had been superseded by the internal-combustion engine. Interest in the engine has recently revived for its potential use in spacecraft and sensitive environments, because of its lack of exhaust fume emissions.

The Reverend Dr Robert Stirling (October 25, 1790 – June 6, 1878) was a Scottish clergyman, and coinventor of a highly efficient heat engine. All closed-cycle regenerative gas engines are now known as Stirling engines.

Biography

Stirling was born at Cloag Farm near Methven, Perthshire in Scotland, the third of eight children. He soon became concerned about the danger the workers in his parish faced from steam engines, which frequently exploded because of the poor quality of the iron boilerplate available at the time, and decided to improve the design of an existing air engine in the hope that it would provide a safer alternative. Stirling's engine could not explode, because it worked at a lower pressure, and could not cause steam burns. They had seven children, including the locomotive engineers Patrick Stirling and James Stirling (engineer).

Later, in Kilmarnock, he collaborated with another inventor, Thomas Morton, who provided workshop facilities for Stirling's research.

Robert's brother James, also an engineer, built a large air engine at his Dundee Foundry Company.

In a letter of 1876, Robert Stirling acknowledged the importance of Henry Bessemer's new invention - the Bessemer process for the manufacture of steel - which made steam engines safer and threatened to make the air engine obsolete.

The theoretical basis of Stirling's engine, the Stirling cycle, would not be fully understood until the work of Sadi Carnot (1796 - 1832). Carnot produced (and published in 1825) a general theory of heat engines, the Carnot cycle, of which the Stirling cycle is a similar case.