"In thermodynamics, the Joule\u2013Thomson effect (also known as the Joule\u2013Kelvin effect, Kelvin\u2013Joule effect, or Joule\u2013Thomson expansion) describes the temperature change of a gas or liquid when it is forced through a valve or porous plug while kept insulated so that no heat is exchanged with the environment. This procedure is called a throttling process or Joule\u2013Thomson process."@en . . .