Regenerative cooling is a method of cooling gases in which compressed gas is cooled by allowing it to expand and thereby take heat from the surroundings.
The cooled expanded gas then passes through a heat exchanger where it cools the incoming compressed gas.
[1] In 1857, Siemens introduced the regenerative cooling concept with the Siemens cycle.
[2] In 1895, William Hampson in England[3] and Carl von Linde in Germany[4] independently developed and patented the Hampson–Linde cycle to liquefy air using the Joule–Thomson expansion process and regenerative cooling.
[5] On 10 May 1898, James Dewar used regenerative cooling to become the first to statically liquefy hydrogen.