THREE STAGE LINEAR SPLIT-STIRLING CRYOCOOLER WITH 1 TO 2 K MAGNETIC COLD STAGE

A CRYOCOOLER IS PROPOSED FOR SPACE-BORNE INFRARED ASTRONOMICAL TELESCOPES WHICH REQUIRE 50 MW OR LESS COOLING AT 1 TO 2 K. IT CONSISTS OF A LINEAR DRIVE THREE STAGE SPLIT-STIRLING CRYOCOOLER WHICH WILL PRODUCE REFRIGERATION AT 8 K TO COOL A NBSN AC SUPERCONDUCTING MAGNET AND A GGG MAGNETIC COLD STAGE. THE PHASE I EFFORT IS A DESIGN STUDY THAT WILL RESULT IN A PRELIMINARY DESIGN. NOVEL FEATURES INCLUDE A FLEXIBLE SUSPENSION SYSTEM FOR THE MULTISTAGE EXPANDER, A HIGH HEAT STORAGE COLD REGENERATOR, GAS THERMAL SWITCHES, AND A CONDUCTIVELY COOLED 10 K SUPERCONDUCTING MAGNET. LONG LIFE IS ACHIEVED BY HAVING NO WEARING PARTS, LUBRICANTS, OR OTHER ORGANIC MATERIALS IN CONTACT WITH THE GAS. THE CRYOCOOLER SHOULD ALSO BE REASONABLY LIGHT, EFFICIENT, AND FREE OF VIBRATION. THE BASIC LONG LIFE CRYOCOOLER TECHNOLOGY CAN READILY BE APPLIED TO HIGHER TEMPERATURE APPLICATIONS.