5.20 External Combustion Engines
FIGURE 5.42
Q:What type of energy does the piston have when it moves back and forth inside the cylinder?
A:Like anything else that is moving, the moving piston has kinetic energy.
Summary
- A combustion engine is a complex machine that burns fuel to produce thermal energy and then uses the thermal
energy to do work. - An external combustion engine burns fuel externally, or outside the engine.
- An external combustion engine burns fuel to heat water and produce steam. The steam is under pressure and
is used to push a piston back and forth inside a cylinder. As the piston moves back and forth, it moves a piston
rod, which can do work.
Vocabulary
- combustion engine: Complex machine that burns fuel to produce thermal energy and uses the thermal energy
to do work. - external combustion engine: Engine that burns fuel externally, or outside the engine.
Explore More
Do a Web quest to learn more about steam engines, including when they were invented and how they changed
industry and transportation. Make a list of all the other uses of steam engines that you find. Start your Web quest
with the following URLs:
http://www.egr.msu.edu/~lira/supp/steam/
http://inventors.about.com/library/inventors/blsteamengine.htm
http://en.wikipedia.org/wiki/Steam_power_during_the_Industrial_Revolution