James Watt (19 January 1736 – 19 August 1819) was a Scottish mathematician and engineer. He did not invent the first steam engine, but he did modify it to work better. There were other patented steam engines (such as the Savery and Newcomen steam engines) in use by the time Watt started his work on them. His major contribution is in developing the modern form of the steam engine. The Watt steam engine is credited for driving the Industrial Revolution of the 18th and 19th centuries.James Watt was a brilliant engineer and he also transformed the Newcomen engine.
James Watt was born on 19 January 1736 in Greenock, Renfrewshire, a seaport on the Firth of Clyde. His father was a shipwright, ship owner and contractor, and served as the town's chief baillie, while his mother, Agnes Muirhead, came from a distinguished family and was well educated. Both were Presbyterians and strong Covenanters. Watt's grandfather, Thomas Watt, taught mathematics and was a baillie to the Baron of Cartsburn. Watt did not go to school every day. At first, he was mostly schooled at home by his mother but later he attended Greenock grammar school. He exhibited great manual dexterity and an aptitude for mathematics, although Latin and Greek failed to interest him, and he absorbed the legends and lore of the Scottish people.
The centrifugal governor [change]
One of Watt's many improvements was the invention of a "centrifugal governor" to regulate automatically the speed of the engine. This is most obvious on steam engines where it regulates the admission of steam into the cylinder(s). It is also found on internal combustion engines and variously fueled turbines, and in some modern striking clocks.
A centrifugal governor is a homeostatic device which controls the speed of an engine by regulating the amount of "intermediate substance" (steam) which drives the machine. This keeps a near constant speed whatever the load or fuel supply conditions. It uses the principle of proportional control: this means the cut-off of (in this case) steam varies according to the speed of the machine.
On Watt's fly-ball device, as the machine speeds up, the balls fly round faster. As they fly round faster, they move out from the central post. As they move out from the central post, they close the steam supply more firmly. As they do so, the machine slows down and the balls spin more slowly, and allow more steam into the cylinders. In addition, the system has a safety release valve to allow excess steam to escape without driving the wheels. 500 Boulton & Watt engines engines were built by the firm between 1775 and 1800.
Later, in 1872, Willard Gibbs showed that all regulating systems must balance two opposing forces.
Other websites [change]
Note: This link may not be simple.
- Tann, Jennifer (2004). "James Watt (1736–1819)". Oxford Dictionary of National Biography. Oxford, England: Oxford University Press.
- Hills, Richard Leslie 1993. Power from steam: a history of the stationary steam engine. Cambridge University Press. ISBN 0-521-45834-X, 9780521458344