Title:
【発明の名称】混合ガスの冷却方法
Document Type and Number:
Japanese Patent JP2000516698
Kind Code:
A
Abstract:
A miniature mixed gas refrigeration system and method of operation are disclosed, having a coaxial catheter with an inner high pressure supply lumen and an outer low pressure return lumen. An optimum gas mixture is formulated from a group of component fluids, according to calculated thermodynamic properties of a group of candidate fluid mixtures. The gas mixture is pressurized by a compressor to a pressure less than 420 psia, for safety reasons. The distal portion of the outer lumen contains a micro-miniature heat exchanger constructed of laminated plates or sheets. The plates or sheets establish high pressure and low pressure passageways, with high surface area, having a tortuous path for the gas flow to maximize heat exchange. The high pressure outlet of the heat exchanger is connected to a Joule-Thomson expansion element where the high pressure gas is expanded isenthalpically to a lower temperature at least as low as 183K. This low temperature gas cools a heat transfer element mounted in the outer wall of the catheter, to cool an external object. Return gas flows back through the heat exchanger to pre-cool the incoming high pressure gas mixture.
Inventors:
Doback John Dee The Third
Radebeau Ray
Huber Marcia El
McCard Eric Dee
Radebeau Ray
Huber Marcia El
McCard Eric Dee
Application Number:
JP50984998A
Publication Date:
December 12, 2000
Filing Date:
August 06, 1997
Export Citation:
Assignee:
Cryogen Incorporated
THE UNITED STATES OF AMERICA
THE UNITED STATES OF AMERICA
International Classes:
F25D3/10; A61B18/02; C09K5/04; F25B9/00; F25B9/02; F28D7/12; F28F13/06; F28F21/08; F25B7/00; (IPC1-7): F25D3/10; A61B18/02
Attorney, Agent or Firm:
Minoru Nakamura (6 outside)