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Joule-Thomson effect

American  
[jool-tom-suhn, joul-] / ˈdʒulˈtɒm sən, ˈdʒaʊl- /

noun

Thermodynamics.
  1. the change of temperature that a gas exhibits during a throttling process, shown by passing the gas through a small aperture or porous plug into a region of low pressure.


Joule-Thomson effect British  

noun

  1. Also called: Joule-Kelvin effect.  a change in temperature of a thermally insulated gas when it is forced through a small hole or a porous material. For each gas there is a temperature of inversion above which the change is positive and below which it is negative

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of Joule-Thomson effect

1895–1900; named after J. P. Joule and Sir W. Thomson