working substance

American  

noun

1. a substance, usually a fluid, that undergoes changes in pressure, temperature, volume, or form as part of a process for accomplishing work.

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working substance British  

noun

1. the fluid, esp water, steam, or compressed air, that operates an engine, refrigerator, etc

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Etymology

Origin of working substance

First recorded in 1895–1900

Example Sentences

Heat transfer Qh occurs into the working substance during the isothermal path AB, which takes place at constant temperature Th .

From Textbooks • Aug. 12, 2015

Heat transfer Qc occurs out of the working substance during the isothermal path CD, which takes place at constant temperature Tc .

From Textbooks • Aug. 12, 2015

They differ from it, however, in the fact that their working substance is not air, but a mixture of gases—a necessary consequence of internal combustion.

From The Project Gutenberg Encyclopedia Volume 1 of 28 by Project Gutenberg

The practical drawbacks to employing air as the working substance of a heat-engine are so great that its use has been very limited.

From The Project Gutenberg Encyclopedia Volume 1 of 28 by Project Gutenberg

Thus by a cyclical process, which leaves the working substance as it was, work is done at the expense of heat taken from the refrigerator, which Thomson's postulate affirms to be impossible.

From Lord Kelvin An account of his scientific life and work by Gray, Andrew