VERY EFFICIENT HEAT EXCHANGER FOR CRYOGEN FREE MRI MAGNET

摘要

A heat exchanger (5) includes a thermally conductive cylindrical container (40), at least one thermally conductive tube (30), a cooling column (90), and a cryogen coldhead (100). The cooling column and coldhead condense gaseous helium to liquid helium to maintain a reservoir of liquid helium in the thermally conductive cylindrical container (40). The at least one thermally conductive tube (30) coils circumferentially around the container (40), and extends to at least one superconducting magnet coil heat exchanger (20), and back. The tube forms a selected loop which holds gaseous helium at pressure up about 104 bar (1500 PSI) or room temperature to about 0.75 bar at cryogenic temperatures.

主权项

1. A heat exchanger comprising:
a thermally conductive cylindrical container containing helium; at least one thermally conductive tube coiled circumferentially around the container and connected in a closed loop to at least one superconducting coil heat exchanger and containing gaseous helium; a cooling column connected to the thermally conductive cylindrical container to receive helium gas therefrom and supply liquid helium thereto; a cryogenic coldhead mounted to the cooling column which condenses helium gas in the cooling column into cold liquid helium.