Text 1 Steam Power and the Industrial Revolution: 1760-1840
The Industrial Revolution began in England, then spread throughout Europe and then North America during the late 18th and early 19th centuries when the life of ordinary people was changed dramatically, forever, by a series of engineering inventions and industrial achievements allowing industry to develop so fast that society could barely keep up. The ultimate goal of the Industrial Revolution was to rely less on human labor in manufacturing processes, and to alter the industrial steps that used to be powered by Man into another form that is powered by machines, which was an idea that occupied the minds of engineers and industrialists for many years before. This dream came true with the discovery of steam power and the invention and development of the steam engine. The steam engine was used in many industrial settings, especially mining, where the first engines pumped water from deep workings. Early mills had run successfully with water power, but by using a steam engine a factory could be located anywhere, not just near water. Water power varied with the seasons, and was not available at times due to freezing, floods and dry spells.
In 1775, James Watt formed an engine-building and engineering partnership with the manufacturer Matthew Boulton. The partnership of Boulton and Watt became one of the most important businesses of the Industrial Revolution and served as a kind of creative technical center for much of the British economy. The partners solved technical problems and spread the solutions to other companies.
From mines, to mills, steam engines found many uses in a variety of other industries. The introduction of steam engines improved productivity and technology, and allowed the creation of smaller and better engines. After Richard Trevithick's development of the high-pressure engine, transport applications became possible, and steam engines found their way to boats, railways, farms and road vehicles. Steam engines are an example of how changes brought by industrialization led to even more changes in other areas.
From http://www.bibalex.org/psc/en/home/sciplanetdetails.aspx?id=71
Text 2 Modern Steam
The steam turbine continues to be a major factor in electric power generation throughout the world. Even nuclear power plants use the heat from a controlled nuclear chain reaction to produce needed steam. In the United States, more than 88 percent of all electricity is produced by steam turbines. As mentioned earlier, there are basically three stages of matter: Solid, liquid and gas. Each stage is held together by a different level of molecular force. With water, gaseous steam takes up space due to its molecules being furthest apart. However, when enough pressure is applied to steam, an amazing thing happens. The molecules are forced together to the point that the water becomes more like a liquid again, while retaining the properties of a gas. It is at this point that it becomes a supercritical fluid.
Many of today's power plants use supercritical steam, with pressure and temperature at the critical point. This means supercritical steam power plants operate at much higher temperatures and pressures than plants using subcritical steam. Water is actually heated to such a high pressure that boiling does not even occur.
The resulting high-pressure fluid of supercritical steam provides excellent energy efficiency. With the aid of high pressure, supercritical steam turbines can be driven to much higher speeds for the same amount of heat energy as traditional steam power. They also release less CO2 exhaust into the atmosphere. Additionally, new high-pressure boilers built with rocket technology are being developed to further control the levels of CO2 emitted. Some boilers will even cool the steam back into a liquid and channel it into the ground to capture emissions.
From http://science.howstuffworks.com/steam-technology8.htm
UNIT 4
Exercise 14, p. 58.
Student A
Student B
From http://en.wikipedia.org
Exercise 15, p. 59.