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Zaxis Inc. LLC
801.264.1000
2442 South 2570 West
West Valley City, UT 84119
its surroundings or if the process takes place quickly enough to prevent any significant
heat transfer. This is essentially the case in a number of important devices, including
air compressors. An adiabatic expansion is usually accompanied by a decrease in the
gas temperature. This can be observed in a common aerosol can, which becomes cold
after some compressed gas is released. The reason for the temperature drop is that
the gas is released too quickly to absorb any significant heat energy from its surround
-
ings.
Work performed in expanding the released gas drains some internal energy of the gas
still in the can, making it colder. However, after the metal of the can becomes cold
the process is no longer adiabatic. In a similar fashion, adiabatic compression usually
increases the temperature of a gas, since work is done on the system by the surround-
ings. For example, when air is pumped into an automobile tire, the air temperature
rises as a result of adiabatic compression.
