Pulse Tube Cryocooler - Part 1

In this video i expand on the resonant linear motor from my previous video and use it to drive a linear compressor for a pulse-tube refrigerator. A pulse tube refrigerator is used to reach cryogenic temperatures, with some going into the sub-kelvin temperature range. These are typically used in labs for scientific experiments that require extreme low temperatures, or for sensors on sattelites/spacecraft, like the optics on the James Webb Space Telescope. From a thermodynamic standpoint, a pulse tube cryocooler is effectively the same as a Stirling or Gifford-McMahon (GM) cooling cycle, but it replaces the displacer (or expander piston in the case of an alpha-stirling) with a gas piston. With careful tuning of a needle valve, inertance tube (gas momentum tube), and buffer volume, the phase of the gas piston’s motion is shifted from the pressure oscillations of the compressor (by ~60-90 degrees), allowing heat pumping to occur out of the cold end. The major advantage of this device is that it elimin